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Diagnosing arthritis in children
SYMPOSIUM: CONNECTIVE TISSUE AND BONE
Diagnosing arthritis in children
Classification of juvenile idiopathic arthritis
Charlotte Ratcliff Graeme Denman Sharmila Jandial
Characteristic
Clinical features
Age at onset Minimum duration Subtypes Systemic
<16 years 6 weeks
Helen Foster Oligoarthritis
Abstract Arthritis in children is common, and a major cause of potential morbidity, with significant long-term consequences, joint damage and disability if left untreated. Diagnosing Juvenile Idiopathic Arthritis (JIA) can be challenging, and relies heavily on clinical assessment; investigations are helpful to exclude other conditions, but are often normal in JIA at presentation. The history may be vague, and the child may be too young to verbalise symptoms; detailed probing for inflammatory symptoms and a comprehensive examination of the child’s joints are therefore essential. If JIA is suspected, early referral to specialist multidisciplinary teams facilitates prompt treatment relief of symptoms, and achieves disease control. The emergence of novel and biologic agents, as well as earlier and more aggressive approaches to treatment, has helped to significantly improve clinical outcomes.
Polyarthritis
Enthesitis-relateda arthritis
Psoriatic arthritis
Keywords joint swelling; juvenile idiopathic arthritis; limping child; pGALS
Juvenile Idiopathic Arthritis (JIA) is the most common chronic inflammatory arthritis of childhood, encompassing a heterogeneous group of conditions of unknown aetiology with the same prevalence as childhood epilepsy and diabetes (1 in 1000); see Table 1 for a description of the individual JIA subtypes. The emergence of novel biologic agents, as well as a move towards earlier and more aggressive treatment regimens, has dramatically improved the outcome for children and young people (CYP) with JIA. Furthermore, early diagnosis and access to specialist care
Undifferentiated
a
Enthesitis is the term for inflammation of the insertion of ligament, tendon, capsule or fascia to bone, particularly around the foot and knee.
Table 1
facilitates prevention of complications such as joint damage and visual loss due to uveitis, which cause disability and adverse quality of life. There is, however, a recognised delay in diagnosis and referral for CYP with JIA to paediatric rheumatology services; the explanation is multifactorial, including complex pathways of care for CYP presenting to health care professionals in primary care and hospital services rather than paediatric rheumatology directly, reduced awareness about arthritis, and many clinicians who first encounter these children report low selfconfidence in their musculoskeletal (MSK) clinical skills. This article aims to increase awareness and knowledge about how to identify CYP with possible JIA, with three illustrative clinical case scenarios.
Charlotte Ratcliff BSc (Hons) MBBS Dip Med Ed GP, registrar currently working in Paediatric Rheumatology, Great North Children’s Hospital, Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK. Competing interests: none declared. Graeme Denman MBBS GP, currently working in Paediatric Rheumatology as a Specialty Doctor, Great North Children’s Hospital, Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK. Competing interests: none declared. Sharmila Jandial MBChB MRCPCH Cert Med Ed, Consultant in Paediatric Rheumatology, Great North Children’s Hospital, Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK. Competing interests: none declared.
Case 1: Chloe’s story Chloe is a 3-year-old girl who presented to the emergency department (ED) with her Mum with a 2-week history of intermittent limp. Up until this point she had been walking confidently from around the age of 14 months, but now asked to be
Helen Foster MD FRCP FRCPCH DCH Cert Med Ed, Professor of Paediatric Rheumatology and Honorary Consultant, Newcastle University, UK and Great North Children’s Hospital, Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK. Competing interests: none declared.
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Arthritis Fever Rash 1e4 joints affected during the first 6months Persistent e affects no more than four joints throughout course Extended e affects more than four joints after first 6-months Rheumatoid factor þve e affects five or more joints in first 6 months Rheumatoid factor ve e affects five or more joints in first 6 months Arthritis and enthesitis, or arthritis or enthesitis with at least two of the following: Sacroiliac joint tenderness Inflammatory back pain HLA-B27þ Family history of HLA-B27þ related disease Arthritis and psoriasis or arthritis and at least two of: Dactylitis Nail changes Family history of psoriasis Arthritis of unknown cause or not fulfilling above categories
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Please cite this article as: Ratcliff C et al., Diagnosing arthritis in children, Paediatrics and Child Health, https://doi.org/10.1016/ j.paed.2019.09.007
SYMPOSIUM: CONNECTIVE TISSUE AND BONE
appetite was poor and her parents reported that she had become more withdrawn in recent weeks. In clinic, Lily looked pale but did not have any palpable lymph nodes or hepatosplenomegaly; cardiovascular, respiratory and abdominal examination was unremarkable. She did, however, have obvious swelling of her knees, ankles, elbows, wrists and the small joints of her hands with restricted passive movement (Figure 2).
carried downstairs in the morning. Mum also mentioned that she was ‘grumpy’ after car journeys and ‘just not right’. That said, Chloe was not complaining much in the way of pain, despite falling over a few days before the onset of her symptoms. A recent coryzal illness had settled in the last week. In the department, Chloe appeared well and was apyrexial; general assessment (cardiovascular, respiratory and abdominal examination) was normal. A paediatric Gait, Arms, Legs and Spine (pGALS) assessment confirmed a limp, with the left knee held in flexion, along with an effusion and thigh muscle wasting (Figure 1). She had normal movement in both hips; however, there was restriction and possible swelling in her right ankle. Investigations revealed normal Full Blood Count (FBC), Erythrocyte Sedimentation Rate (ESR), C-Reactive Protein (CRP) and sterile blood cultures; an X-ray of her knee and ankle did not show any bone pathology. She was discharged with a prescription for ibuprofen and referred to the local paediatric rheumatology team as an outpatient.
Case 3: Connor’s story Connor is a 3-year-old boy who presented to the ED with a 5-day history of temperatures and leg pain. This was on the background of coryzal illness, sticky eyes, sore throat, intermittent abdominal pain, reduced appetite and a reluctance to walk. His parents described an erythematous rash over his trunk, legs and arms. On examination, he was pyrexial, reluctant to weight bear and had a mildly inflamed pharynx but no visible exudate on his tonsils. No other focus of infection was found. Initial blood work showed a White Blood Count (WBC) of 32 (10*9/L; normal range 5.5e15.5), neutrophil count of 29 (10*9/ L; 1.5e8.5), platelet count of 884 (10*9/L; 150e450), haemoglobin of 95g/L (115e155), ESR of 104 mm/hour (1e10), CRP of 178 mg/L (0e5) and ferritin of over 15000 mg/L. His blood film was reported as showing reactive changes only. During his inpatient stay for further investigation, he was noted to have a rise in temperature at similar times each day; this was associated with a salmon-pink rash which improved as the temperature normalised (Figure 3).
Case 2: Lily’s story Lily is a 12-year-old girl referred urgently to paediatric rheumatology by her GP with a 2-month history of painful, swollen metacarpophalangeal (MCP) joints, bilateral knee and ankle pain, and associated lethargy. She described feeling stiff in the morning for around 90 minutes, and also after sitting for a prolonged period of time (e.g. after a double lesson of maths). Lily was a keen runner but had stopped this activity due to pain. Her
The limping child e thinking about Chloe and Connor’s story The differential diagnosis for the limping child e that is, a child presenting with an asymmetrical gait e is extensive, and comprises a spectrum of aetiologies from benign, self-limiting conditions through to life-threatening diseases such as septic arthritis and acute lymphoblastic leukaemia (ALL). Persistent limp and daytime symptoms are exclusion criteria for growing pains, a common label to describe children with aches and pains of unclear cause (see http://www.pmmonline.org/page.aspx? id¼808 for the ‘rules of growing pains’). Differentiating the potential diagnosis of limp can be facilitated by knowledge of the
Figure 1 Flexion contracture left knee.
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Figure 2 Polyarthritis affecting the small joints of the hands and wrists.
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SYMPOSIUM: CONNECTIVE TISSUE AND BONE
Common and significant causes of limp by age In all patients consider:
Age:
1e3
4e10
11e16
Osteomyelitis/septic arthritis Non-accidental injury Testicular torsion/inguinal hernia/appendicitis/ urine infection Juvenile idiopathic arthritis Metabolic conditions (e.g. rickets) Haematological disease (e.g. sickle cell anaemia) Toddler’s fracture Developmental dysplasia of the hip Neuroblastoma Transient synovitis Perthes’ disease Acute lymphocytic leukaemia Slipped upper femoral epiphysis Primary bone tumours OsgoodeSchlatter disease SindingeLarsen syndrome
Table 2
-
-
Figure 3 Connor’s rash.
common and significant causes according to age, as shown in Table 2. For the limping child presenting to primary care, indications for same day acute paediatric assessment include: - The very young (under 3 years of age) - The ill and febrile - The non-weight bearing - Children with painful, restricted joints - The child who is immunosuppressed
Clues from the history “How has their general health been?” e Asking about red flags The presence of systemic symptoms should raise concerns about multisystem illness (e.g. JSLE or inflammatory bowel syndromes and further serious pathology such as malignancy, bacterial infection or trauma (including non-accidental injury; NAI) must be excluded before diagnosing JIA. It is therefore essential to check for the presence of ‘red flags’, as listed in Table 3.
Multiple joint swelling e Lily’s story In Lily’s case of polyarthritis, the likely diagnosis is JIA although leukaemia should be considered. Other conditions to consider in a case of multiple joint swelling include: - Post viral arthritis (e.g. rubella, varicella, Epstein Barr virus infection) - Multi-system disease such as Juvenile Systemic Lupus Erythematosus (JSLE), Juvenile Dermatomyositis (JDM) or vasculitis - Rheumatic fever (a form of reactive arthritis that follows streptococcal infection). Although uncommon in the UK, this is very common in other parts of the world; the arthritis often flits between multiple joints, and diagnosis rests on clinical grounds in combination with evidence of streptococcal
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infection (i.e. elevated Anti-Streptolysin O Titre; ASOT) which may arise from throat (or skin) infection. There is an associated risk of carditis Inflammatory bowel disease: there is often an oligoarticular or asymmetrical pattern of joint involvement which may precede the onset of gastrointestinal symptoms Metabolic conditions (osteomalacia or rickets) Chromosomal conditions (e.g. Down’s syndrome associated arthritis) Inherited metabolic conditions (e.g. mucopolysaccharidoses)
Musculoskeletal red flags Night time wakening with pain Bone pain Fever Anorexia Weight loss Malaise Features suggestive of non-accidental injury Table 3
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“Did anything precede their symptoms?” e Distinguishing reactive and traumatic causes Typically, reactive arthritis occurs around 7e10 days after the acute illness and spontaneously remits within 2e3 weeks of onset; gastrointestinal infections may cause a reactive arthritis but in the older patient sexually acquired infection needs to be sensitively explored. Falls in children are common and may be a ‘red herring’ as children with arthritis are often more prone to falling. It is important to explore further for inconsistency or discrepancy between circumstance and degree of injury, which should raise suspicion about NAI.
difficulty of localising the site of joint pathology from history alone (as with Chloe). Here, special attention was given to her hip joints to exclude transient synovitis or Perthes’ disease, both of which often show restriction in internal rotation of the hip in the early stages. It is also important to look for any clues (e.g. facial expressions or limb withdrawal) that movements are painful, and check all joints looking for seemingly asymptomatic joint involvement e a lack of symmetry can be helpful. Referred pain should also not be overlooked e.g. hip joint disease may present with knee or thigh pain. Joint swelling is the most reliable physical sign of JIA and there may, or may not be, increased warmth over inflamed joints. Swelling is very difficult to assess at the hip or shoulder and can be missed even in peripheral joints if there is mild or symmetrical involvement. Ankle swelling is best observed from behind. Frequent practice of pGALS, especially on healthy children, is important to appreciate normal ranges of movement as joint ‘restriction’ e a common finding in JIA e can be easily missed especially with symmetrical joint disease. Reduced muscle bulk suggests chronicity due to disuse, and it is likely that Chloe’s swollen knee has been present for several weeks given her quadriceps wasting.
“What are they like in the morning?” e Mechanical versus inflammatory features Joint swelling is a prominent symptom of inflammatory conditions such as JIA, but can be subtle and often missed by parents (as well as health care professionals). To be diagnostic of JIA, joint swelling needs to persist for several weeks (by definition, more than 6 weeks) and other conditions excluded. Morning stiffness may manifest itself through functional change (i.e. difficulty dressing or managing the stairs: “my child walks like an old man”) or through a noticeable change in behaviour; parents often mention that their child is particularly miserable in the morning. Prolonged inactivity may precipitate stiffness known as ‘gelling’, and the child may describe difficulty getting up after sitting for a sustained length of time e.g. following long car journeys. Pain is not always a presenting complaint and may not be verbally expressed in the young child. As such, it is important to ask open, probing questions about any mood changes in the child, or avoidance of activities (e.g. no longer participating in play or sports). If pain is described, it may ease with activity and movement, and worsen with rest. Mechanical causes for MSK symptoms such as those arising from injury or hypermobility, often have pain exacerbated by activity and worse at the end of the day, and there may be locking or giving way; stiffness or swelling is largely absent or transitory.
Extra-articular examination In the presence of red flags, or suspicion of multisystem disease from the history, it is important to perform a comprehensive general examination and check especially for lymphadenopathy, hepatosplenomegaly, rashes, features of anaemia and check blood pressure, perform fundoscopy and undertake urinalysis (for evidence of vasculitis). Uveitis is an important complication of JIA (present in 30% of all JIA cases) and the highest risk is in the preschool age with oligoarticular presentation and positive antinuclear factor (ANA). Importantly, the most common form of uveitis in JIA is asymptomatic; the eye is not red or painful and visual symptoms do not occur until the eye involvement is advanced. A slit lamp examination is needed to detect uveitis and is performed by an experienced ophthalmologist. Acute uveitis with a painful red eye can occur in JIA, but is more associated with enthesitis-related arthritis (ERA) and children who carry the Human Leukocyte Antigen (HLA)-B27.
“What can they no longer do?” e Developmental milestones A history of regression of achieved motor milestones is often present with inflammatory joint disease and can manifest as the child becoming ’clumsy’ or withdrawing from activity (e.g. no longer walking independently). Regression of a previously attained motor milestone suggests an acquired condition whereas delay alone might suggest a congenital or inherited condition (such as development dysplasia of the hip (DDH) or muscular dystrophy).
Clues to the JIA subtype Nail pitting, psoriatic skin lesions and dactylitis (‘sausage’ digit appearance affecting fingers or toes) are features of psoriatic arthropathy, although joint involvement can predate skin changes and often involves small joints of the hand and foot asymmetrically. ERA typically presents with an oligoarthritis affecting the large joints of the lower limb, usually older boys who may be HLA-B27 positive. Enthesitis tends to cause severe localised pain, frequently occurring at the heel (at the Achilles tendon insertion point) or around the patella.
Clues from examination pGALS: the paediatric Gait, Arms, Legs and Spine examination Both Chloe and Lily were examined using pGALS, a validated and simple MSK basic examination (Figure 4). Free educational resources to demonstrate pGALS are available online (www. pmmonline.org), and via the pGALS app. pGALS has the benefit of quickly assessing all joints; this is important given the sometimes vague presentation of MSK problems and the
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Investigations (and their pitfalls) Raised acute phase reactants (ESR, CRP and serum ferritin concentration) can be present in active systemic-onset JIA (SoJIA), however, blood tests and radiographs are often initially normal in many other types of JIA and so there may be false reassurance from negative tests; prompt referral to paediatric rheumatology
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Figure 4 pGALS assessment. This figure is available on the pGALS app and is used with permission from Newcastle University, UK.
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for suspected JIA should be made irrespective of tests or awaiting the results. There is no specific test for JIA and the role of investigation is to help exclude alternative serious diagnoses. Chloe’s doctor followed the ED’s ‘limping child’ protocol, with investigations to exclude possible infection and malignancy; synovial fluid examination to rule out sepsis is mandatory in the assessment of a child with a single, swollen joint and mycobacterial infection may also need to be excluded. Table 4 lists the rationale for potential investigations in CYP presenting with MSK symptoms.
Imaging and special tests MRI is sensitive to early changes of inflammatory arthritis but availability may be limited and, in young children, invariably requires sedation or general anaesthetic. Ultrasonography is also sensitive to early changes, is well tolerated by young children, and is increasingly used to identify subclinical synovitis when clinical suspicion is high based on history but there is little in the way of joint swelling on examination. Arthroscopy, or biopsy, is rarely indicated and ideally only after consultation with paediatric rheumatology.
Autoantibodies Autoantibodies are rarely diagnostic (approximately 50% of patients with JIA are ANA negative) but in the presence of arthritis are useful to determine JIA subtype and prognosis e.g. ANA positivity indicates a high risk of chronic anterior uveitis. Positive ANA can occur in autoimmune rheumatic conditions (such as JSLE) but can also be present with transient illness and in healthy children. Rheumatoid factor (RF) is a poor diagnostic test, being present in only a minority of children with JIA. It is, however, associated with a more aggressive disease course and worse prognosis if positive in a child with polyarticular disease.
Principles of management in JIA Table 5 lists current therapeutic options in the management of JIA. Optimal management entails prompt referral to an experienced multidisciplinary team, and close liaison with school, social and primary healthcare providers. Chloe’s journey Chloe was seen as an outpatient 4 weeks after her discharge with little change in her symptoms. In the absence of trauma and infection and now with a 6-week history of persistent joint swelling affecting less than 5 joints, she was diagnosed with oligoarticular JIA. Chloe and her Mum were introduced to the
Possible investigations in the child presenting with MSK symptoms Test
Rationale
ESR CRP FBC Blood film
ESR of >40 mm/h is a risk factor for septic arthritis A CRP >10 mg/l is a risk factor for septic arthritis Neutrophilia is suggestive of septic arthritis. A WCC of >12109 is a risk factor for septic arthritis A normal blood film does not exclude leukaemia or other malignancy. A bone marrow aspirate may be required and specialist opinion is required where there is clinical concern Blood cultures are positive in 46%e80% of patients with osteomyelitis and 22%e50% of patients with septic arthritis Raised ASOT suggests current or recent streptococcal infection and is present in up to 80% of patients with acute rheumatic fever Raised levels can suggest malignancy (especially lymphoma) but sensitivity and specificity is low May be elevated in neuroblastoma May be normal even with significant pathology (e.g. sepsis, early Perthes’ disease, transient synovitis, malignancy, JIA). Repeat radiographs after a period of review may be useful (e.g. detecting periosteal reaction in toddler’s fracture or evolving Perthes’ disease). Anterioreposterior and ‘frog leg lateral’ hip x-rays should be undertaken if slipped upper femoral epiphysis (SUFE) suspected. Caution is required in conditions of the hip where bilateral changes may occur (e.g. SUFE, hip dysplasia) Very sensitive in detecting hip and joint effusions. Ultrasound findings will not differentiate among infection, blood or reactive fluid. Does not exclude osteomyelitis but may show periosteal reaction suggestive of osteomyelitis Very sensitive in identifying early sepsis, Perthes’ disease, inflammatory disease and tumours when the pathological area is localised on clinical examination. May not always be able to differentiate infection from inflammation. Gadolinium enhancement can be used to improve detection of infection, synovitis and tumours Very sensitive in identifying early osteomyelitis when an obvious focus of infection cannot be localised. May also detect early Perthes’ disease, tumours and stress fractures such as toddler fractures and particularly when the history is vague. Very sensitive in identifying early osteomyelitis when an obvious focus of infection cannot be localised. May also detect early Perthes’ disease, tumours and stress fractures such as toddler fractures and particularly when the history is vague.
Blood culture Anti-streptolysin O titre (ASOT) Lactate dehydrogenase Urine catecholamines Plain radiography
Ultrasonography
MRI
Bone scan
CT
Table 4
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Available medical treatment for JIA Medication
Comment
Non-steroidal anti-inflammatories Corticosteroids
May provide short term symptomatic relief but are not disease modifying
Methotrexate Cytokine modulators (biologics)
Intra-articular injections e first line management in oligoarticular JIA Pulsed IV Methylprednisolone - induces remission at disease onset, during flares of polyarthritis, or in those with features of systemic onset JIA Oral route e minimised with the early use of intra-articular injections and disease modifying anti-rheumatic drugs First line in polyarticular JIA, enthesitis-related arthritis, systemic JIA and in oligoarthritis that is extending or failing to respond to intra-articular corticosteroids Used in the child with severe disease and resistant to, or intolerant of methotrexate
Table 5
arthritis. Many patients require the use of biologic medication, often in combination with methotrexate, and the prognosis is variable.
paediatric rheumatology specialist nursing team for ongoing support and advice. She was reviewed that day by the ophthalmology team with no evidence of uveitis but kept on 3-monthly screening. Chloe returned a fortnight later for an intra-articular steroid injection of her knee and ankle under general anaesthetic. She was later seen by the physiotherapy team to instigate her physical rehabilitation with exercises to be done at home with the support of her family.
Connor’s journey Connor continued to have temperature rises of up to 40 degrees daily with increased frequency, and investigations were negative for infection and malignancy. In particular, the diagnosis of leukaemia was considered and a bone marrow examination under the haematology team was normal. He was referred to the paediatric rheumatology team who noted effusion of the right knee and ankle, and a rash typical of systemic-onset JIA over his trunk and legs. He was treated with a 3-day pulse of IV methylprednisolone followed by oral prednisolone; his temperature and rash settled, and he began to mobilise with improvement in his joint symptoms.
Oligoarticular JIA This is the most common of the JIA subtypes (70% of all cases), and carries the best prognosis. It often presents in pre-school girls with knee or ankle involvement. Methotrexate is recommended in patients with severe uveitis, arthritis of a critical joint (e.g. wrist, hip, temporomandibular joint) or in those children who develop extended oligoarticular JIA.
Systemic-onset JIA (SoJIA) This is the least common subtype of JIA (10% of cases) but carries the worst prognosis. One-third of children develop severe polyarthritis and the disease carries significant mortality as a result of complications such as carditis, macrophage activation and sepsis; infection risk is compounded by systemic immunosuppression. SoJIA is characterised by an acute illness with daily (quotidian) fever, maculopapular rash often worse with pyrexia, serositis, lymphadenopathy and hepatosplenomegaly. Systemic features can pre-date the arthritis by several weeks. Treatment includes aggressive use of corticosteroids (often given intravenously during the acute systemic illness), high dose parenteral methotrexate, and biologic therapy; currently interleukin 1 or 6 blockade are the preferred options.
Lily’s journey Lily was diagnosed on clinical grounds with polyarticular JIA based on the symmetrical involvement of small and large joints. Her FBC, blood film and inflammatory markers were normal. Ophthalmology review did not reveal pre-existing uveitis and a follow up appointment was arranged. Lily was admitted for a 3day pulse of intravenous (IV) methylprednisolone and during the admission, the family met the multidisciplinary team including the occupational therapist and physiotherapist. She and her family were able to discuss her diagnosis and treatment with the specialist nurse who specifically counselled her about methotrexate and supported her to have her first dose as an inpatient. Close communication with Lily’s GP was maintained on discharge, with advice on avoiding live vaccines, vigilance regarding infection especially shingles (Lily was known to have prior exposure to Varicella) and advice on when to seek medical attention with illness.
Avoiding delay in JIA diagnosis Improved medical management and experienced multidisciplinary team working has markedly changed the prospects for CYP with JIA. Many will achieve remission (either on or off treatment) and those transferring to adult care can expect to have good disease control, avoiding the considerable potential for morbidity associated with JIA. This is achieved through early referral to specialist paediatric services, and will be maintained
Polyarticular JIA In adolescent girls, polyarticular JIA can follow a course similar to that of adult rheumatoid arthritis, especially those with positive rheumatoid factor, and carry the same association with HLADR4. They may develop skin nodules and potentially an erosive
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Figure 5 Free CPD course from Newcastle University e Introduction to Paediatric Musculoskeletal Clinical Skills pGALS.
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Figure 6 Free CPD course from Newcastle University e Paediatric Musculoskeletal Medicine in Primary Care e A Guide for GPs.
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Paediatric Musculoskeletal Medicine in Primary Care e A Guide for GPs: https://cpd.ncl.ac.uk/courses - a short course targeted at primary care clinicians looking to improve their assessment of MSK presentations in CYP (free) (Figure 6). Paediatric Musculoskeletal Matters e a free online educational resource with links to pGALS video, information about clinical assessment, normal development, limping child and referral guidance with illustrative case histories and videos - www. pmmonline.org
through prompt recognition of suspected JIA by non-specialists, general practitioners and paediatricians in training, and avoidance of the common pitfalls. A FURTHER READING Cope S, Denman G, Foster H, Jandial S. Paediatric Gait, Arms, Legs and Spine examination (pGALS) e a case based discussion. Paediatrics Child Health 2018; 28: 73e83. Foster HE, Jandial S. pGALS e paediatric Gait Arms Legs and Spine: a simple examination of the musculoskeletal system. Paediatr Rheumatol 2013; 11: 44. Hughes M, Wyllie R, Foster HE. Chronic arthritis in children and young people. Medicine 2018; 46: 222e30. Mosley E. Practical guide to treating children with juvenile idiopathic arthritis. Paediatrics Child Health 2015; 25: 587e91. Petty RE, Southwood TR, Manners P, et al. International League of Associations for Rheumatology classification of juvenile idiopathic arthritis: second revision, Edmonton, 2001. J Rheumatol 2004; 31: 390e92. Ravelli A, Martini A. Juvenile idiopathic arthritis. Lancet 2007; 369: 767e78. Smith E, Anderson M, Foster HE. The child with a limp: a symptom and not a diagnosis. Arch Dis Child Educ Pract Ed 2012; 97: 185e93.
Practice points - Pain may not be apparent or verbalised in children with JIA; look for stiffness, swelling, limp or functional impairment - Minor trauma and prodromal viral illness may be red herrings in the history - Detection of joint swelling in clinical practice can be difficult, especially if symmetrical; look also for restriction of joint movement - Systematic examination of all joints can pick up affected joints not detected by history alone - Blood tests and radiographs are often normal in a diagnosis of JIA; referral is recommended as soon as arthritis is suspected - Rheumatoid factor is invariably negative in JIA, but in the presence of arthritis a positive test is associated with a worse prognosis - In the absence of trauma or sepsis, JIA is the most likely diagnosis of a single swollen joint in a child - Early referral with suspected JIA is always indicated. Eye screening for asymptomatic uveitis is important - Live vaccines are contraindicated with systemic immunosuppressive treatments. Varicella and measles status should be known and appropriate advice given
ONLINE RESOURCES
pGALS App e a study aid developed by Newcastle University, UK that takes you through the pGALS steps. Available to download for free in the Google Play and Apple store. Introduction to Paediatric Musculoskeletal Clinical Skills e pGALS: https://cpd.ncl.ac.uk/courses - an introductory short course from the authors of Paediatric Musculoskeletal Matters (PMM) providing knowledge to support MSK assessment of CYP in primary and secondary care (free) (Figure 5).
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Diagnosing arthritis in children
Classification of juvenile idiopathic arthritis
Charlotte Ratcliff Graeme Denman Sharmila Jandial
Characteristic
Clinical features
Age at onset Minimum duration Subtypes Systemic
<16 years 6 weeks
Helen Foster Oligoarthritis
Abstract Arthritis in children is common, and a major cause of potential morbidity, with significant long-term consequences, joint damage and disability if left untreated. Diagnosing Juvenile Idiopathic Arthritis (JIA) can be challenging, and relies heavily on clinical assessment; investigations are helpful to exclude other conditions, but are often normal in JIA at presentation. The history may be vague, and the child may be too young to verbalise symptoms; detailed probing for inflammatory symptoms and a comprehensive examination of the child’s joints are therefore essential. If JIA is suspected, early referral to specialist multidisciplinary teams facilitates prompt treatment relief of symptoms, and achieves disease control. The emergence of novel and biologic agents, as well as earlier and more aggressive approaches to treatment, has helped to significantly improve clinical outcomes.
Polyarthritis
Enthesitis-relateda arthritis
Psoriatic arthritis
Keywords joint swelling; juvenile idiopathic arthritis; limping child; pGALS
Juvenile Idiopathic Arthritis (JIA) is the most common chronic inflammatory arthritis of childhood, encompassing a heterogeneous group of conditions of unknown aetiology with the same prevalence as childhood epilepsy and diabetes (1 in 1000); see Table 1 for a description of the individual JIA subtypes. The emergence of novel biologic agents, as well as a move towards earlier and more aggressive treatment regimens, has dramatically improved the outcome for children and young people (CYP) with JIA. Furthermore, early diagnosis and access to specialist care
Undifferentiated
a
Enthesitis is the term for inflammation of the insertion of ligament, tendon, capsule or fascia to bone, particularly around the foot and knee.
Table 1
facilitates prevention of complications such as joint damage and visual loss due to uveitis, which cause disability and adverse quality of life. There is, however, a recognised delay in diagnosis and referral for CYP with JIA to paediatric rheumatology services; the explanation is multifactorial, including complex pathways of care for CYP presenting to health care professionals in primary care and hospital services rather than paediatric rheumatology directly, reduced awareness about arthritis, and many clinicians who first encounter these children report low selfconfidence in their musculoskeletal (MSK) clinical skills. This article aims to increase awareness and knowledge about how to identify CYP with possible JIA, with three illustrative clinical case scenarios.
Charlotte Ratcliff BSc (Hons) MBBS Dip Med Ed GP, registrar currently working in Paediatric Rheumatology, Great North Children’s Hospital, Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK. Competing interests: none declared. Graeme Denman MBBS GP, currently working in Paediatric Rheumatology as a Specialty Doctor, Great North Children’s Hospital, Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK. Competing interests: none declared. Sharmila Jandial MBChB MRCPCH Cert Med Ed, Consultant in Paediatric Rheumatology, Great North Children’s Hospital, Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK. Competing interests: none declared.
Case 1: Chloe’s story Chloe is a 3-year-old girl who presented to the emergency department (ED) with her Mum with a 2-week history of intermittent limp. Up until this point she had been walking confidently from around the age of 14 months, but now asked to be
Helen Foster MD FRCP FRCPCH DCH Cert Med Ed, Professor of Paediatric Rheumatology and Honorary Consultant, Newcastle University, UK and Great North Children’s Hospital, Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK. Competing interests: none declared.
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Arthritis Fever Rash 1e4 joints affected during the first 6months Persistent e affects no more than four joints throughout course Extended e affects more than four joints after first 6-months Rheumatoid factor þve e affects five or more joints in first 6 months Rheumatoid factor ve e affects five or more joints in first 6 months Arthritis and enthesitis, or arthritis or enthesitis with at least two of the following: Sacroiliac joint tenderness Inflammatory back pain HLA-B27þ Family history of HLA-B27þ related disease Arthritis and psoriasis or arthritis and at least two of: Dactylitis Nail changes Family history of psoriasis Arthritis of unknown cause or not fulfilling above categories
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appetite was poor and her parents reported that she had become more withdrawn in recent weeks. In clinic, Lily looked pale but did not have any palpable lymph nodes or hepatosplenomegaly; cardiovascular, respiratory and abdominal examination was unremarkable. She did, however, have obvious swelling of her knees, ankles, elbows, wrists and the small joints of her hands with restricted passive movement (Figure 2).
carried downstairs in the morning. Mum also mentioned that she was ‘grumpy’ after car journeys and ‘just not right’. That said, Chloe was not complaining much in the way of pain, despite falling over a few days before the onset of her symptoms. A recent coryzal illness had settled in the last week. In the department, Chloe appeared well and was apyrexial; general assessment (cardiovascular, respiratory and abdominal examination) was normal. A paediatric Gait, Arms, Legs and Spine (pGALS) assessment confirmed a limp, with the left knee held in flexion, along with an effusion and thigh muscle wasting (Figure 1). She had normal movement in both hips; however, there was restriction and possible swelling in her right ankle. Investigations revealed normal Full Blood Count (FBC), Erythrocyte Sedimentation Rate (ESR), C-Reactive Protein (CRP) and sterile blood cultures; an X-ray of her knee and ankle did not show any bone pathology. She was discharged with a prescription for ibuprofen and referred to the local paediatric rheumatology team as an outpatient.
Case 3: Connor’s story Connor is a 3-year-old boy who presented to the ED with a 5-day history of temperatures and leg pain. This was on the background of coryzal illness, sticky eyes, sore throat, intermittent abdominal pain, reduced appetite and a reluctance to walk. His parents described an erythematous rash over his trunk, legs and arms. On examination, he was pyrexial, reluctant to weight bear and had a mildly inflamed pharynx but no visible exudate on his tonsils. No other focus of infection was found. Initial blood work showed a White Blood Count (WBC) of 32 (10*9/L; normal range 5.5e15.5), neutrophil count of 29 (10*9/ L; 1.5e8.5), platelet count of 884 (10*9/L; 150e450), haemoglobin of 95g/L (115e155), ESR of 104 mm/hour (1e10), CRP of 178 mg/L (0e5) and ferritin of over 15000 mg/L. His blood film was reported as showing reactive changes only. During his inpatient stay for further investigation, he was noted to have a rise in temperature at similar times each day; this was associated with a salmon-pink rash which improved as the temperature normalised (Figure 3).
Case 2: Lily’s story Lily is a 12-year-old girl referred urgently to paediatric rheumatology by her GP with a 2-month history of painful, swollen metacarpophalangeal (MCP) joints, bilateral knee and ankle pain, and associated lethargy. She described feeling stiff in the morning for around 90 minutes, and also after sitting for a prolonged period of time (e.g. after a double lesson of maths). Lily was a keen runner but had stopped this activity due to pain. Her
The limping child e thinking about Chloe and Connor’s story The differential diagnosis for the limping child e that is, a child presenting with an asymmetrical gait e is extensive, and comprises a spectrum of aetiologies from benign, self-limiting conditions through to life-threatening diseases such as septic arthritis and acute lymphoblastic leukaemia (ALL). Persistent limp and daytime symptoms are exclusion criteria for growing pains, a common label to describe children with aches and pains of unclear cause (see http://www.pmmonline.org/page.aspx? id¼808 for the ‘rules of growing pains’). Differentiating the potential diagnosis of limp can be facilitated by knowledge of the
Figure 1 Flexion contracture left knee.
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Figure 2 Polyarthritis affecting the small joints of the hands and wrists.
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Common and significant causes of limp by age In all patients consider:
Age:
1e3
4e10
11e16
Osteomyelitis/septic arthritis Non-accidental injury Testicular torsion/inguinal hernia/appendicitis/ urine infection Juvenile idiopathic arthritis Metabolic conditions (e.g. rickets) Haematological disease (e.g. sickle cell anaemia) Toddler’s fracture Developmental dysplasia of the hip Neuroblastoma Transient synovitis Perthes’ disease Acute lymphocytic leukaemia Slipped upper femoral epiphysis Primary bone tumours OsgoodeSchlatter disease SindingeLarsen syndrome
Table 2
-
-
Figure 3 Connor’s rash.
common and significant causes according to age, as shown in Table 2. For the limping child presenting to primary care, indications for same day acute paediatric assessment include: - The very young (under 3 years of age) - The ill and febrile - The non-weight bearing - Children with painful, restricted joints - The child who is immunosuppressed
Clues from the history “How has their general health been?” e Asking about red flags The presence of systemic symptoms should raise concerns about multisystem illness (e.g. JSLE or inflammatory bowel syndromes and further serious pathology such as malignancy, bacterial infection or trauma (including non-accidental injury; NAI) must be excluded before diagnosing JIA. It is therefore essential to check for the presence of ‘red flags’, as listed in Table 3.
Multiple joint swelling e Lily’s story In Lily’s case of polyarthritis, the likely diagnosis is JIA although leukaemia should be considered. Other conditions to consider in a case of multiple joint swelling include: - Post viral arthritis (e.g. rubella, varicella, Epstein Barr virus infection) - Multi-system disease such as Juvenile Systemic Lupus Erythematosus (JSLE), Juvenile Dermatomyositis (JDM) or vasculitis - Rheumatic fever (a form of reactive arthritis that follows streptococcal infection). Although uncommon in the UK, this is very common in other parts of the world; the arthritis often flits between multiple joints, and diagnosis rests on clinical grounds in combination with evidence of streptococcal
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infection (i.e. elevated Anti-Streptolysin O Titre; ASOT) which may arise from throat (or skin) infection. There is an associated risk of carditis Inflammatory bowel disease: there is often an oligoarticular or asymmetrical pattern of joint involvement which may precede the onset of gastrointestinal symptoms Metabolic conditions (osteomalacia or rickets) Chromosomal conditions (e.g. Down’s syndrome associated arthritis) Inherited metabolic conditions (e.g. mucopolysaccharidoses)
Musculoskeletal red flags Night time wakening with pain Bone pain Fever Anorexia Weight loss Malaise Features suggestive of non-accidental injury Table 3
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“Did anything precede their symptoms?” e Distinguishing reactive and traumatic causes Typically, reactive arthritis occurs around 7e10 days after the acute illness and spontaneously remits within 2e3 weeks of onset; gastrointestinal infections may cause a reactive arthritis but in the older patient sexually acquired infection needs to be sensitively explored. Falls in children are common and may be a ‘red herring’ as children with arthritis are often more prone to falling. It is important to explore further for inconsistency or discrepancy between circumstance and degree of injury, which should raise suspicion about NAI.
difficulty of localising the site of joint pathology from history alone (as with Chloe). Here, special attention was given to her hip joints to exclude transient synovitis or Perthes’ disease, both of which often show restriction in internal rotation of the hip in the early stages. It is also important to look for any clues (e.g. facial expressions or limb withdrawal) that movements are painful, and check all joints looking for seemingly asymptomatic joint involvement e a lack of symmetry can be helpful. Referred pain should also not be overlooked e.g. hip joint disease may present with knee or thigh pain. Joint swelling is the most reliable physical sign of JIA and there may, or may not be, increased warmth over inflamed joints. Swelling is very difficult to assess at the hip or shoulder and can be missed even in peripheral joints if there is mild or symmetrical involvement. Ankle swelling is best observed from behind. Frequent practice of pGALS, especially on healthy children, is important to appreciate normal ranges of movement as joint ‘restriction’ e a common finding in JIA e can be easily missed especially with symmetrical joint disease. Reduced muscle bulk suggests chronicity due to disuse, and it is likely that Chloe’s swollen knee has been present for several weeks given her quadriceps wasting.
“What are they like in the morning?” e Mechanical versus inflammatory features Joint swelling is a prominent symptom of inflammatory conditions such as JIA, but can be subtle and often missed by parents (as well as health care professionals). To be diagnostic of JIA, joint swelling needs to persist for several weeks (by definition, more than 6 weeks) and other conditions excluded. Morning stiffness may manifest itself through functional change (i.e. difficulty dressing or managing the stairs: “my child walks like an old man”) or through a noticeable change in behaviour; parents often mention that their child is particularly miserable in the morning. Prolonged inactivity may precipitate stiffness known as ‘gelling’, and the child may describe difficulty getting up after sitting for a sustained length of time e.g. following long car journeys. Pain is not always a presenting complaint and may not be verbally expressed in the young child. As such, it is important to ask open, probing questions about any mood changes in the child, or avoidance of activities (e.g. no longer participating in play or sports). If pain is described, it may ease with activity and movement, and worsen with rest. Mechanical causes for MSK symptoms such as those arising from injury or hypermobility, often have pain exacerbated by activity and worse at the end of the day, and there may be locking or giving way; stiffness or swelling is largely absent or transitory.
Extra-articular examination In the presence of red flags, or suspicion of multisystem disease from the history, it is important to perform a comprehensive general examination and check especially for lymphadenopathy, hepatosplenomegaly, rashes, features of anaemia and check blood pressure, perform fundoscopy and undertake urinalysis (for evidence of vasculitis). Uveitis is an important complication of JIA (present in 30% of all JIA cases) and the highest risk is in the preschool age with oligoarticular presentation and positive antinuclear factor (ANA). Importantly, the most common form of uveitis in JIA is asymptomatic; the eye is not red or painful and visual symptoms do not occur until the eye involvement is advanced. A slit lamp examination is needed to detect uveitis and is performed by an experienced ophthalmologist. Acute uveitis with a painful red eye can occur in JIA, but is more associated with enthesitis-related arthritis (ERA) and children who carry the Human Leukocyte Antigen (HLA)-B27.
“What can they no longer do?” e Developmental milestones A history of regression of achieved motor milestones is often present with inflammatory joint disease and can manifest as the child becoming ’clumsy’ or withdrawing from activity (e.g. no longer walking independently). Regression of a previously attained motor milestone suggests an acquired condition whereas delay alone might suggest a congenital or inherited condition (such as development dysplasia of the hip (DDH) or muscular dystrophy).
Clues to the JIA subtype Nail pitting, psoriatic skin lesions and dactylitis (‘sausage’ digit appearance affecting fingers or toes) are features of psoriatic arthropathy, although joint involvement can predate skin changes and often involves small joints of the hand and foot asymmetrically. ERA typically presents with an oligoarthritis affecting the large joints of the lower limb, usually older boys who may be HLA-B27 positive. Enthesitis tends to cause severe localised pain, frequently occurring at the heel (at the Achilles tendon insertion point) or around the patella.
Clues from examination pGALS: the paediatric Gait, Arms, Legs and Spine examination Both Chloe and Lily were examined using pGALS, a validated and simple MSK basic examination (Figure 4). Free educational resources to demonstrate pGALS are available online (www. pmmonline.org), and via the pGALS app. pGALS has the benefit of quickly assessing all joints; this is important given the sometimes vague presentation of MSK problems and the
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Investigations (and their pitfalls) Raised acute phase reactants (ESR, CRP and serum ferritin concentration) can be present in active systemic-onset JIA (SoJIA), however, blood tests and radiographs are often initially normal in many other types of JIA and so there may be false reassurance from negative tests; prompt referral to paediatric rheumatology
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Figure 4 pGALS assessment. This figure is available on the pGALS app and is used with permission from Newcastle University, UK.
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for suspected JIA should be made irrespective of tests or awaiting the results. There is no specific test for JIA and the role of investigation is to help exclude alternative serious diagnoses. Chloe’s doctor followed the ED’s ‘limping child’ protocol, with investigations to exclude possible infection and malignancy; synovial fluid examination to rule out sepsis is mandatory in the assessment of a child with a single, swollen joint and mycobacterial infection may also need to be excluded. Table 4 lists the rationale for potential investigations in CYP presenting with MSK symptoms.
Imaging and special tests MRI is sensitive to early changes of inflammatory arthritis but availability may be limited and, in young children, invariably requires sedation or general anaesthetic. Ultrasonography is also sensitive to early changes, is well tolerated by young children, and is increasingly used to identify subclinical synovitis when clinical suspicion is high based on history but there is little in the way of joint swelling on examination. Arthroscopy, or biopsy, is rarely indicated and ideally only after consultation with paediatric rheumatology.
Autoantibodies Autoantibodies are rarely diagnostic (approximately 50% of patients with JIA are ANA negative) but in the presence of arthritis are useful to determine JIA subtype and prognosis e.g. ANA positivity indicates a high risk of chronic anterior uveitis. Positive ANA can occur in autoimmune rheumatic conditions (such as JSLE) but can also be present with transient illness and in healthy children. Rheumatoid factor (RF) is a poor diagnostic test, being present in only a minority of children with JIA. It is, however, associated with a more aggressive disease course and worse prognosis if positive in a child with polyarticular disease.
Principles of management in JIA Table 5 lists current therapeutic options in the management of JIA. Optimal management entails prompt referral to an experienced multidisciplinary team, and close liaison with school, social and primary healthcare providers. Chloe’s journey Chloe was seen as an outpatient 4 weeks after her discharge with little change in her symptoms. In the absence of trauma and infection and now with a 6-week history of persistent joint swelling affecting less than 5 joints, she was diagnosed with oligoarticular JIA. Chloe and her Mum were introduced to the
Possible investigations in the child presenting with MSK symptoms Test
Rationale
ESR CRP FBC Blood film
ESR of >40 mm/h is a risk factor for septic arthritis A CRP >10 mg/l is a risk factor for septic arthritis Neutrophilia is suggestive of septic arthritis. A WCC of >12109 is a risk factor for septic arthritis A normal blood film does not exclude leukaemia or other malignancy. A bone marrow aspirate may be required and specialist opinion is required where there is clinical concern Blood cultures are positive in 46%e80% of patients with osteomyelitis and 22%e50% of patients with septic arthritis Raised ASOT suggests current or recent streptococcal infection and is present in up to 80% of patients with acute rheumatic fever Raised levels can suggest malignancy (especially lymphoma) but sensitivity and specificity is low May be elevated in neuroblastoma May be normal even with significant pathology (e.g. sepsis, early Perthes’ disease, transient synovitis, malignancy, JIA). Repeat radiographs after a period of review may be useful (e.g. detecting periosteal reaction in toddler’s fracture or evolving Perthes’ disease). Anterioreposterior and ‘frog leg lateral’ hip x-rays should be undertaken if slipped upper femoral epiphysis (SUFE) suspected. Caution is required in conditions of the hip where bilateral changes may occur (e.g. SUFE, hip dysplasia) Very sensitive in detecting hip and joint effusions. Ultrasound findings will not differentiate among infection, blood or reactive fluid. Does not exclude osteomyelitis but may show periosteal reaction suggestive of osteomyelitis Very sensitive in identifying early sepsis, Perthes’ disease, inflammatory disease and tumours when the pathological area is localised on clinical examination. May not always be able to differentiate infection from inflammation. Gadolinium enhancement can be used to improve detection of infection, synovitis and tumours Very sensitive in identifying early osteomyelitis when an obvious focus of infection cannot be localised. May also detect early Perthes’ disease, tumours and stress fractures such as toddler fractures and particularly when the history is vague. Very sensitive in identifying early osteomyelitis when an obvious focus of infection cannot be localised. May also detect early Perthes’ disease, tumours and stress fractures such as toddler fractures and particularly when the history is vague.
Blood culture Anti-streptolysin O titre (ASOT) Lactate dehydrogenase Urine catecholamines Plain radiography
Ultrasonography
MRI
Bone scan
CT
Table 4
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Available medical treatment for JIA Medication
Comment
Non-steroidal anti-inflammatories Corticosteroids
May provide short term symptomatic relief but are not disease modifying
Methotrexate Cytokine modulators (biologics)
Intra-articular injections e first line management in oligoarticular JIA Pulsed IV Methylprednisolone - induces remission at disease onset, during flares of polyarthritis, or in those with features of systemic onset JIA Oral route e minimised with the early use of intra-articular injections and disease modifying anti-rheumatic drugs First line in polyarticular JIA, enthesitis-related arthritis, systemic JIA and in oligoarthritis that is extending or failing to respond to intra-articular corticosteroids Used in the child with severe disease and resistant to, or intolerant of methotrexate
Table 5
arthritis. Many patients require the use of biologic medication, often in combination with methotrexate, and the prognosis is variable.
paediatric rheumatology specialist nursing team for ongoing support and advice. She was reviewed that day by the ophthalmology team with no evidence of uveitis but kept on 3-monthly screening. Chloe returned a fortnight later for an intra-articular steroid injection of her knee and ankle under general anaesthetic. She was later seen by the physiotherapy team to instigate her physical rehabilitation with exercises to be done at home with the support of her family.
Connor’s journey Connor continued to have temperature rises of up to 40 degrees daily with increased frequency, and investigations were negative for infection and malignancy. In particular, the diagnosis of leukaemia was considered and a bone marrow examination under the haematology team was normal. He was referred to the paediatric rheumatology team who noted effusion of the right knee and ankle, and a rash typical of systemic-onset JIA over his trunk and legs. He was treated with a 3-day pulse of IV methylprednisolone followed by oral prednisolone; his temperature and rash settled, and he began to mobilise with improvement in his joint symptoms.
Oligoarticular JIA This is the most common of the JIA subtypes (70% of all cases), and carries the best prognosis. It often presents in pre-school girls with knee or ankle involvement. Methotrexate is recommended in patients with severe uveitis, arthritis of a critical joint (e.g. wrist, hip, temporomandibular joint) or in those children who develop extended oligoarticular JIA.
Systemic-onset JIA (SoJIA) This is the least common subtype of JIA (10% of cases) but carries the worst prognosis. One-third of children develop severe polyarthritis and the disease carries significant mortality as a result of complications such as carditis, macrophage activation and sepsis; infection risk is compounded by systemic immunosuppression. SoJIA is characterised by an acute illness with daily (quotidian) fever, maculopapular rash often worse with pyrexia, serositis, lymphadenopathy and hepatosplenomegaly. Systemic features can pre-date the arthritis by several weeks. Treatment includes aggressive use of corticosteroids (often given intravenously during the acute systemic illness), high dose parenteral methotrexate, and biologic therapy; currently interleukin 1 or 6 blockade are the preferred options.
Lily’s journey Lily was diagnosed on clinical grounds with polyarticular JIA based on the symmetrical involvement of small and large joints. Her FBC, blood film and inflammatory markers were normal. Ophthalmology review did not reveal pre-existing uveitis and a follow up appointment was arranged. Lily was admitted for a 3day pulse of intravenous (IV) methylprednisolone and during the admission, the family met the multidisciplinary team including the occupational therapist and physiotherapist. She and her family were able to discuss her diagnosis and treatment with the specialist nurse who specifically counselled her about methotrexate and supported her to have her first dose as an inpatient. Close communication with Lily’s GP was maintained on discharge, with advice on avoiding live vaccines, vigilance regarding infection especially shingles (Lily was known to have prior exposure to Varicella) and advice on when to seek medical attention with illness.
Avoiding delay in JIA diagnosis Improved medical management and experienced multidisciplinary team working has markedly changed the prospects for CYP with JIA. Many will achieve remission (either on or off treatment) and those transferring to adult care can expect to have good disease control, avoiding the considerable potential for morbidity associated with JIA. This is achieved through early referral to specialist paediatric services, and will be maintained
Polyarticular JIA In adolescent girls, polyarticular JIA can follow a course similar to that of adult rheumatoid arthritis, especially those with positive rheumatoid factor, and carry the same association with HLADR4. They may develop skin nodules and potentially an erosive
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Figure 5 Free CPD course from Newcastle University e Introduction to Paediatric Musculoskeletal Clinical Skills pGALS.
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Figure 6 Free CPD course from Newcastle University e Paediatric Musculoskeletal Medicine in Primary Care e A Guide for GPs.
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Paediatric Musculoskeletal Medicine in Primary Care e A Guide for GPs: https://cpd.ncl.ac.uk/courses - a short course targeted at primary care clinicians looking to improve their assessment of MSK presentations in CYP (free) (Figure 6). Paediatric Musculoskeletal Matters e a free online educational resource with links to pGALS video, information about clinical assessment, normal development, limping child and referral guidance with illustrative case histories and videos - www. pmmonline.org
through prompt recognition of suspected JIA by non-specialists, general practitioners and paediatricians in training, and avoidance of the common pitfalls. A FURTHER READING Cope S, Denman G, Foster H, Jandial S. Paediatric Gait, Arms, Legs and Spine examination (pGALS) e a case based discussion. Paediatrics Child Health 2018; 28: 73e83. Foster HE, Jandial S. pGALS e paediatric Gait Arms Legs and Spine: a simple examination of the musculoskeletal system. Paediatr Rheumatol 2013; 11: 44. Hughes M, Wyllie R, Foster HE. Chronic arthritis in children and young people. Medicine 2018; 46: 222e30. Mosley E. Practical guide to treating children with juvenile idiopathic arthritis. Paediatrics Child Health 2015; 25: 587e91. Petty RE, Southwood TR, Manners P, et al. International League of Associations for Rheumatology classification of juvenile idiopathic arthritis: second revision, Edmonton, 2001. J Rheumatol 2004; 31: 390e92. Ravelli A, Martini A. Juvenile idiopathic arthritis. Lancet 2007; 369: 767e78. Smith E, Anderson M, Foster HE. The child with a limp: a symptom and not a diagnosis. Arch Dis Child Educ Pract Ed 2012; 97: 185e93.
Practice points - Pain may not be apparent or verbalised in children with JIA; look for stiffness, swelling, limp or functional impairment - Minor trauma and prodromal viral illness may be red herrings in the history - Detection of joint swelling in clinical practice can be difficult, especially if symmetrical; look also for restriction of joint movement - Systematic examination of all joints can pick up affected joints not detected by history alone - Blood tests and radiographs are often normal in a diagnosis of JIA; referral is recommended as soon as arthritis is suspected - Rheumatoid factor is invariably negative in JIA, but in the presence of arthritis a positive test is associated with a worse prognosis - In the absence of trauma or sepsis, JIA is the most likely diagnosis of a single swollen joint in a child - Early referral with suspected JIA is always indicated. Eye screening for asymptomatic uveitis is important - Live vaccines are contraindicated with systemic immunosuppressive treatments. Varicella and measles status should be known and appropriate advice given
ONLINE RESOURCES
pGALS App e a study aid developed by Newcastle University, UK that takes you through the pGALS steps. Available to download for free in the Google Play and Apple store. Introduction to Paediatric Musculoskeletal Clinical Skills e pGALS: https://cpd.ncl.ac.uk/courses - an introductory short course from the authors of Paediatric Musculoskeletal Matters (PMM) providing knowledge to support MSK assessment of CYP in primary and secondary care (free) (Figure 5).
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