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Self-assessment
SELF-ASSESSMENT
Self-assessment Questions
fused and the thalami are adjoined to the third ventricle. Optic nerves appear normal. (a) Given the MRI report, what is the most likely diagnosis? i Hydranencephaly ii Porencephaly iii Aicardi syndrome iv Holoprosencephaly v DandyeWalker malformation (b) Which of the following are recognized associated clinical manifestations? i Incontinentia pigmenti ii Cleft palate iii Retinitis pigmentosa iv Peg-shaped teeth v Diabetes insipidus vi Chorioretinal lacunae
Case 1 A term male infant is born as a spontaneous delivery to a multiparous mother. Routine antenatal ultrasound at 20 weeks of gestation suggested borderline ventriculomegaly. Further scanning at 31 weeks reported mild bilateral ventriculomegaly. Mother has three healthy children, but previously suffered three miscarriages. Apart from prescribed citalopram in the first trimester, she is otherwise well. The baby weighs 3550 g and OFC 35 cm. There are no significant dysmorphic features on examination. Cranial ultrasound demonstrates distorted ventricular architecture and absence of midline structures. MRI of the brain (Figure 1) confirms the absence of the septum pellucidum and incomplete corpus callosum. There is a single midline ventricle. The frontal lobes are partially
Case 2 A 6-year-old girl presents to her GP with a slow growing lump on her head which was noted when brushing her hair. The lump had never caused any pain or exudation. She is otherwise well, with no recent history of weight loss or head injury. There is no other significant past medical history. Examination revealed a 3 3 cm smooth, firm, nonfluctuant mass over the occiput. The mass is non-tender and there is no local erythema or regional lymphadenopathy. General examination is unremarkable, with no evidence of organomegaly, skin pigmentation or other skeletal lesions. A CT scan of the head is requested (Figure 2). (a) How best would you describe the appearance evident on the CT image i Wormian bones ii Encephalocoele iii Lytic lesion iv Pepper pot skull v Depression fracture (b) She is referred to the Neurosurgeons for biopsy, but on assessment 4 weeks later, the mass had resolved without intervention. What is the likely diagnosis? i Epidermal cyst ii Langerhan’s histiocytosis iii Dermoid cyst iv Potts puffy tumour v Osteoid osteoma (c) What investigation is recommended as part of the baseline evaluation? i CT chest ii Pulmonary function tests iii Endoscopy iv Audiology assessment v Early morning urine osmolality
Figure 1 Coronal T2 weighted MRI of the brain.
Jeff Morgan MBBS BSc (Experimental Pathology) MRCPCH is an ST5 in Paediatrics at Royal Gwent Hospital, Newport, UK. Conflict of interest: none. Chetan S Ashtekar MBBS MRCPCH FRCPCH is a Consultant Paediatrician at the Royal Gwent Hospital, Newport, UK. Conflict of interest: none.
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Ó 2011 Elsevier Ltd. All rights reserved.
SELF-ASSESSMENT
Case 3 A 14-year-old boy presents to A&E for the third time in 10 days experiencing palpitations, dizziness and syncope either on minimal exertion or at rest. He was previously diagnosed with a cardiac condition aged 9 and had routine cardiology review every 2 years. He was not taking any prescribed medication as had remained asymptomatic until recently. There is a family history of sensorineural hearing deficit, but no history of sudden death in a young family member. A 12 lead ECG was performed (Figure 3). (a) What is the diagnosis? i First degree heart block ii Sinus arrhythmia iii Ventricular ectopics iv Jervell and Lange-Nielsen Syndrome v WolffeParkinsoneWhite Syndrome (b) The arrhythmia reverted spontaneously. After discussing the case with the cardiologist, what might he suggest as the next step? i Start flecainide ii Immediate radio-frequency ablation iii Give iv adenosine iv Do nothing and continue everyday life v Exercise and electrophysiology tests
Figure 2
Figure 3
PAEDIATRICS AND CHILD HEALTH 22:1
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Ó 2011 Elsevier Ltd. All rights reserved.
SELF-ASSESSMENT
Answers
Case 4 A male infant of unknown gestation was born to nonconsanguineous parents. Limited antenatal history was available because of concealed pregnancy. He responded to initial resuscitation measures and transferred to NICU for further management. Examination on admission revealed a number of striking dysmorphic anomalies e complete absence of the left upper limb, abnormal posture of a hypoplastic right forearm and absent right thumb. No obvious cutaneous lesions were noted. A nasogastric tube was successfully sited. A 2/6 ejection systolic murmur was auscultated at the left upper sternal edge. Saturations remained between 60e70% despite 100% oxygen, therefore prostaglandins were commenced. The visiting Cardiologist reported AVSD, double outlet right ventricle with hypoplastic left pulmonary artery on echocardiography. Blood test confirmed normal FBC parameters. His chest X-ray can be seen in Figure 4. (a) Given the history and chest X-ray findings, what is the most likely diagnosis? i HolteOram syndrome ii Fanconi anaemia iii VACTERL iv Maternal cocaine mis-use v Thrombocytopenia Absent Radii (TAR) syndrome (b) What genetic defect is commonly associated with the likely diagnosis? i None ii 22q11 microdeletion iii 1q21.1 microdeletion iv TBX5 gene mutation v Chromosomal fragility
Case 1 (a) iv (b) ii, v Explanation Holoprosencephaly (HPE) is a rare, complex congenital disorder of incomplete division of the prosencephalon which should normally occur between the 4th and 6th week of gestation. Incidence is estimated to be 1 in 10,000 live births. During the early stages of cortical development, interruption of midline division results in a spectrum of cerebral hemisphere, thalamic and corpus callosum dysgenesis. Aetiology is unknown, although associations with Trisomy 13 and maternal diabetes have been reported. There are four generally accepted subtypes of HPE, defined by the extent of hemispheric non-division: i Alobar e the most severe defect with complete, or nearly complete, lack of cerebral hemispheric separation and a single fused monoventricle. ii Semilobar e partial development of the interhemispheric fissure with some degree of separation of the posterior hemispheric portions. Anteriorly, the frontal cerebral hemispheres and thalami are fused. iii Lobar e near complete separation of the cerebral hemispheres with a formed interhemispheric fissure. The frontal horns of lateral ventricles are fused with wide communication with the third ventricle. iv Middle Interhemispheric Variant (MIH) e nonseparation is confined to the posterior frontal and parietal lobes. The genu and splenium of the corpus callosum are usually fully developed. HPE is usually diagnosed during routine antenatal USS, but MRI is the modality of choice. Clinical suspicion maybe aroused in the newborn period, however, the spectrum of characteristic clinical features deviates widely from the grossly severe to more subtle manifestations. Midline defects predominate and tend to equate to the degree of malformation, for example, cyclopia in alobar HPE. Milder features may exhibit as hypotelorism or a single central maxillary incisor. Retinitis pigmentosa is a condition of progressive retinal degeneration. Incontinentia Pigmenti (IP) is an inherited disorder of ectodermal pigmentation of four phases which may also feature ocular and neurodevelopmental abnormalities. Peg-shaped teeth are associated with both IP and ectodermal dysplasia. Invariably all HPE patients have an element of developmental delay and the majority will have abnormal muscle tone to some extent. Approximately 40% will require anti-epileptic treatment for seizures. Central Diabetes Insipidus is the most common endocrine disorder, whereas anterior pituitary dysfunction is observed less frequently. Recommendations are made to assess endocrine function. Mortality is high during the newborn period, but small numbers of HPE patients are surviving into adolescence and adulthood.
Figure 4
PAEDIATRICS AND CHILD HEALTH 22:1
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Ó 2011 Elsevier Ltd. All rights reserved.
SELF-ASSESSMENT
Aicardi Syndrome is a rare X-linked neurodevelopmental disorder characterized by agenesis of the corpus callosum, infantile spasms and pathognomonic chorioretinal lacuna e punched-out, white defects clustered around the optic discs. Porencephaly is demonstrated on MRI as a well defined focal intracranial cyst which may or may not communicate with the ventricles. Hydranencephaly describes the rare, but severe destruction of the cerebral cortices. A large CSF filled sac covered by leptomeninges replaces the hemispheres with almost complete absence of cortical tissue. There is perseveration of the thalami, cerebellum and brainstem. Both porencephaly and hydranencephaly can be secondary to vascular insult. DandyeWalker malformation classically describes the triad of cerebellar vermis hypoplasia, cystic dilatation of the fourth ventricle with enlargement of the posterior fossa.
bony lytic lesion. Cutaneous lesions vary from scaly papular rashes to flared vesicles. Biopsy will assist confirmation of the diagnosis. With reports of posterior pituitary dysfunction in up to 40% of cases, urine osmolality studies are recommended. Unless other symptoms are suggestive from the history, these investigations will suffice in single system disease. More extensive studies will be required for multisystem disease, including skeletal surveys and CT chest. Rarely, the GI tract may be involved. Reticuloendothelial disease carries a worse prognosis. The natural history of single bone lesions cannot be predicted. Some lesions resolve spontaneously, others regress after partial removal by biopsy and curettage. Occasionally, intra-lesional steroid injections are required. If all other therapies fail, 6m of low dose vincristine and oral steroids may be necessary. All patients should be followed up as recurrence is recognized. If this should occur, it usually involves the same system. In contrast, osteoid osteoma tends to provoke pain, more often at night. Osteoma is best demonstrated on CT with three distinct concentric zones e central nidus, fibrovascular rim and an outer reactive sclerosis. These are surgically resected or undergo radiofrequency ablation. Dermoid cysts generally occur along the midline and do not spontaneously resolve. Potts puffy tumour is an osteomyelitis of the frontal bone which may erode causing periosteal or intracranial abscess.
FURTHER READING Hahn JS, Plawner MD. Evaluation and management of children with holoprosencephaly. Pediatr Neurol 2004; 31: 79e88. Kauvar EF, Muenke M. Holoprosencephaly: recommendations for diagnosis and management. Curr Opin Pediatr 2010; 22: 687e95. Kurtz AB, Johnston PT. Case 7: hydranencephaly. Radiology 1999; 210: 419e22. www.radiopaedia.org.
Case 2 (a) iii (b) ii (c) v
FURTHER READING Windebank K, Nanduri V. Langerhans cell histiocytosis. Arch Dis Child 2009; 94: 904e908.
Explanation CT confirms a lytic lesion involving both the inner and outer skull tables with associated soft tissue mass. This appearance is consistent with Langerhans Cell Histiocytosis (LCH), whereas a pepper pot skull signifies multiple punched-out lesions associated with myeloma. Wormian bones are small extra intrasutural bones that maybe found around the lambdoid suture, associated with Osteogenesis Imperfecta. Epidermal cysts are common, well circumscribed cutaneous lesions that lie in or just beneath the skin. LCH is a rare condition with monoclonal proliferation of epidermal Langerhan cells characterized by the Birbeck granule. These act as antigen-presenting cells within the skin. The precipitating cause remains unknown. Manifestations of LCH are extremely diverse, and therefore categorized either as single system or multisystem disease, depending upon organ involvement. Annual incidence in the UK is estimated to be 4 per million children. Those diagnosed with single system disease tend to be older (more than 5), whereas, infants more frequently present with skin/pulmonary concerns. Skeletal disease is the most commonly affected system, the skull in particular. Typical presentation is of a painless, fluctuant swelling. Other sites can include orbital, vertebral and long bones. Imaging reveals the typical punched-out
PAEDIATRICS AND CHILD HEALTH 22:1
Case 3 (a) v (b) i Explanation WolffeParkinsoneWhite (WPW) is an AV re-entry tachycardia, caused by the presence of an accessory atrioventricular connection. Prevalence in children is estimated to be 0.1e0.2% more frequently seen in boys than girls. Approximately 0.5% of children with WPW have preexisting congenital cardiac disease. The typical ECG changes described in WPW consist of a shortened PR interval and widened QRS complex which shows a distinctive slurring of the initial portion of the r wave, known as the ‘delta’ wave. These morphological features are collectively referred to as ventricular preexcitation and normally seen when the patient is not in SVT. Atrial fibrillation is a recognized complication even in paediatric cases (5e10%). This increases the risk of sudden cardiac death, where rapid conduction over the accessory pathway can result in ventricular fibrillation. WPW can be differentiated from first degree heart block where the ECG would show a prolonged PR interval. Sinus arrhythmia is often seen as a variation of PeP interval
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SELF-ASSESSMENT
Case 4 (a) iii (b) i
V: Vertebral anomalies A: Anal anomalies C: Cardiac anomalies T-E: trachea-(o)esophageal abnormalities R: Renal/radius anomalies L: Limb anomalies Approximately 75% of patients will have congenital cardiac disease, most commonly VSD. Hypoplastic or hemi-vertebrae and trachea-oesophageal fistula may both feature in up to 70% of cases. Common limb defects include absent thumbs, polydactyly and forearm defects. Some reports suggest upper limb defects indicate a higher specificity for VACTERL. It is not uncommon to observe asymmetric abnormalities of the limbs. Anal atresia or imperforate anus is seen in approximately 55% of patients, single umbilical artery is not uncommon and 22% have cystic renal disease. No causative factor, genetic or environmental, has yet to be identified for VACTERL. HolteOram Syndrome is an AD inherited syndrome linked with TBX5 gene mutation resulting in heart-upper limb defects. TAR syndrome is distinguished by episodic periods of thrombocytopenia, particularly during infancy, and from varying degrees of hypoplasia, syndactyly or aplasia of the upper limb. TAR is associated with 1q21.1 microdeletions. Fanconi’s anaemia is a rare inherited syndrome of bone marrow failure associated with birth defects including thumb/radial malformation and skin hyperpigmentation. Chromosomal fragility testing assists this diagnosis. Case reports have described distal limb anomalies as a result of cocaine exposure in-utero, however, due to polysubstance mis-use, these are often difficult to attribute to cocaine alone.
Explanation The CXR demonstrates amelia of the left limb, absent right radius and vertebral anomalies. In conjunction with the cardiac defect, these features suggest VACTERL association. VACTERL refers to an association characterized of seemingly non-random pattern of malformations which together are not recognizable of a defined syndrome. Any combination of at least three of the following should prompt the paediatric team to consider the possibility of VACTERL:
FURTHER READING Castori M, Rinaldi R, Cappellacci S, Grammatico P. Tibial developmental field defect is the most common lower limb malformation pattern in VACTERL association. Am J Med Genet Part A 2010; 146A: p1259e66. http://www.vacterl-association.org.uk. Rittler M, Paz JE, Castilla EE. VACTERL association, epidemiological definition and delineation. Am J Med Genet 1996; 63: 529e36.
associated with respiration. Ventricular ectopics are early, broad QRS complexes produced by a premature ventricular ectopic discharge. Patients with Jervell and Lange-Nielsen Syndrome have markedly prolonged QT intervals and congenital deafness. Sudden death may be the first clinical manifestation of WPW. Up to 10% of asymptomatic WPW patients may experience potentially life-threatening arrhythmias, therefore, sitting back and continuing everyday life is not an option. It is recommended to treat symptomatic patients with antiarrhythmics until electrophysiology tests and RF-ablation can be performed. Iv Adenosine is used to attempt initial cardioversion in SVT. This may only achieve transient success but time enough to possibly capture the delta wave. Flecainide is a Class IC anti-arrhythmic (Naþ channel blocker) which reduces conduction through the accessory pathway. Side effects include a metallic taste and proarrhythmias. RF-ablation is reported to be successful in up to 95% of cases but the timing of procedure varies between centres.
FURTHER READING Dubin A. Cardiac arrhythmias. Section 4. In: Kliegman RM, Behrman RE, eds. Nelson textbook of paediatrics. 18th Edn. Philedelphia: Saunders WB, 2007; 1945-1946. Nunez F, Ruiz-Granell R, Martı´nez-Costa C, Morell S, Brines J. Safety and efficacy of flecainide in the treatment of symptomatic children with WolffeParkinsoneWhite syndrome. Pediatr Cardiol 2010; 31: 1162e65.
PAEDIATRICS AND CHILD HEALTH 22:1
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Ó 2011 Elsevier Ltd. All rights reserved.
Self-assessment Questions
fused and the thalami are adjoined to the third ventricle. Optic nerves appear normal. (a) Given the MRI report, what is the most likely diagnosis? i Hydranencephaly ii Porencephaly iii Aicardi syndrome iv Holoprosencephaly v DandyeWalker malformation (b) Which of the following are recognized associated clinical manifestations? i Incontinentia pigmenti ii Cleft palate iii Retinitis pigmentosa iv Peg-shaped teeth v Diabetes insipidus vi Chorioretinal lacunae
Case 1 A term male infant is born as a spontaneous delivery to a multiparous mother. Routine antenatal ultrasound at 20 weeks of gestation suggested borderline ventriculomegaly. Further scanning at 31 weeks reported mild bilateral ventriculomegaly. Mother has three healthy children, but previously suffered three miscarriages. Apart from prescribed citalopram in the first trimester, she is otherwise well. The baby weighs 3550 g and OFC 35 cm. There are no significant dysmorphic features on examination. Cranial ultrasound demonstrates distorted ventricular architecture and absence of midline structures. MRI of the brain (Figure 1) confirms the absence of the septum pellucidum and incomplete corpus callosum. There is a single midline ventricle. The frontal lobes are partially
Case 2 A 6-year-old girl presents to her GP with a slow growing lump on her head which was noted when brushing her hair. The lump had never caused any pain or exudation. She is otherwise well, with no recent history of weight loss or head injury. There is no other significant past medical history. Examination revealed a 3 3 cm smooth, firm, nonfluctuant mass over the occiput. The mass is non-tender and there is no local erythema or regional lymphadenopathy. General examination is unremarkable, with no evidence of organomegaly, skin pigmentation or other skeletal lesions. A CT scan of the head is requested (Figure 2). (a) How best would you describe the appearance evident on the CT image i Wormian bones ii Encephalocoele iii Lytic lesion iv Pepper pot skull v Depression fracture (b) She is referred to the Neurosurgeons for biopsy, but on assessment 4 weeks later, the mass had resolved without intervention. What is the likely diagnosis? i Epidermal cyst ii Langerhan’s histiocytosis iii Dermoid cyst iv Potts puffy tumour v Osteoid osteoma (c) What investigation is recommended as part of the baseline evaluation? i CT chest ii Pulmonary function tests iii Endoscopy iv Audiology assessment v Early morning urine osmolality
Figure 1 Coronal T2 weighted MRI of the brain.
Jeff Morgan MBBS BSc (Experimental Pathology) MRCPCH is an ST5 in Paediatrics at Royal Gwent Hospital, Newport, UK. Conflict of interest: none. Chetan S Ashtekar MBBS MRCPCH FRCPCH is a Consultant Paediatrician at the Royal Gwent Hospital, Newport, UK. Conflict of interest: none.
PAEDIATRICS AND CHILD HEALTH 22:1
42
Ó 2011 Elsevier Ltd. All rights reserved.
SELF-ASSESSMENT
Case 3 A 14-year-old boy presents to A&E for the third time in 10 days experiencing palpitations, dizziness and syncope either on minimal exertion or at rest. He was previously diagnosed with a cardiac condition aged 9 and had routine cardiology review every 2 years. He was not taking any prescribed medication as had remained asymptomatic until recently. There is a family history of sensorineural hearing deficit, but no history of sudden death in a young family member. A 12 lead ECG was performed (Figure 3). (a) What is the diagnosis? i First degree heart block ii Sinus arrhythmia iii Ventricular ectopics iv Jervell and Lange-Nielsen Syndrome v WolffeParkinsoneWhite Syndrome (b) The arrhythmia reverted spontaneously. After discussing the case with the cardiologist, what might he suggest as the next step? i Start flecainide ii Immediate radio-frequency ablation iii Give iv adenosine iv Do nothing and continue everyday life v Exercise and electrophysiology tests
Figure 2
Figure 3
PAEDIATRICS AND CHILD HEALTH 22:1
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Ó 2011 Elsevier Ltd. All rights reserved.
SELF-ASSESSMENT
Answers
Case 4 A male infant of unknown gestation was born to nonconsanguineous parents. Limited antenatal history was available because of concealed pregnancy. He responded to initial resuscitation measures and transferred to NICU for further management. Examination on admission revealed a number of striking dysmorphic anomalies e complete absence of the left upper limb, abnormal posture of a hypoplastic right forearm and absent right thumb. No obvious cutaneous lesions were noted. A nasogastric tube was successfully sited. A 2/6 ejection systolic murmur was auscultated at the left upper sternal edge. Saturations remained between 60e70% despite 100% oxygen, therefore prostaglandins were commenced. The visiting Cardiologist reported AVSD, double outlet right ventricle with hypoplastic left pulmonary artery on echocardiography. Blood test confirmed normal FBC parameters. His chest X-ray can be seen in Figure 4. (a) Given the history and chest X-ray findings, what is the most likely diagnosis? i HolteOram syndrome ii Fanconi anaemia iii VACTERL iv Maternal cocaine mis-use v Thrombocytopenia Absent Radii (TAR) syndrome (b) What genetic defect is commonly associated with the likely diagnosis? i None ii 22q11 microdeletion iii 1q21.1 microdeletion iv TBX5 gene mutation v Chromosomal fragility
Case 1 (a) iv (b) ii, v Explanation Holoprosencephaly (HPE) is a rare, complex congenital disorder of incomplete division of the prosencephalon which should normally occur between the 4th and 6th week of gestation. Incidence is estimated to be 1 in 10,000 live births. During the early stages of cortical development, interruption of midline division results in a spectrum of cerebral hemisphere, thalamic and corpus callosum dysgenesis. Aetiology is unknown, although associations with Trisomy 13 and maternal diabetes have been reported. There are four generally accepted subtypes of HPE, defined by the extent of hemispheric non-division: i Alobar e the most severe defect with complete, or nearly complete, lack of cerebral hemispheric separation and a single fused monoventricle. ii Semilobar e partial development of the interhemispheric fissure with some degree of separation of the posterior hemispheric portions. Anteriorly, the frontal cerebral hemispheres and thalami are fused. iii Lobar e near complete separation of the cerebral hemispheres with a formed interhemispheric fissure. The frontal horns of lateral ventricles are fused with wide communication with the third ventricle. iv Middle Interhemispheric Variant (MIH) e nonseparation is confined to the posterior frontal and parietal lobes. The genu and splenium of the corpus callosum are usually fully developed. HPE is usually diagnosed during routine antenatal USS, but MRI is the modality of choice. Clinical suspicion maybe aroused in the newborn period, however, the spectrum of characteristic clinical features deviates widely from the grossly severe to more subtle manifestations. Midline defects predominate and tend to equate to the degree of malformation, for example, cyclopia in alobar HPE. Milder features may exhibit as hypotelorism or a single central maxillary incisor. Retinitis pigmentosa is a condition of progressive retinal degeneration. Incontinentia Pigmenti (IP) is an inherited disorder of ectodermal pigmentation of four phases which may also feature ocular and neurodevelopmental abnormalities. Peg-shaped teeth are associated with both IP and ectodermal dysplasia. Invariably all HPE patients have an element of developmental delay and the majority will have abnormal muscle tone to some extent. Approximately 40% will require anti-epileptic treatment for seizures. Central Diabetes Insipidus is the most common endocrine disorder, whereas anterior pituitary dysfunction is observed less frequently. Recommendations are made to assess endocrine function. Mortality is high during the newborn period, but small numbers of HPE patients are surviving into adolescence and adulthood.
Figure 4
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Ó 2011 Elsevier Ltd. All rights reserved.
SELF-ASSESSMENT
Aicardi Syndrome is a rare X-linked neurodevelopmental disorder characterized by agenesis of the corpus callosum, infantile spasms and pathognomonic chorioretinal lacuna e punched-out, white defects clustered around the optic discs. Porencephaly is demonstrated on MRI as a well defined focal intracranial cyst which may or may not communicate with the ventricles. Hydranencephaly describes the rare, but severe destruction of the cerebral cortices. A large CSF filled sac covered by leptomeninges replaces the hemispheres with almost complete absence of cortical tissue. There is perseveration of the thalami, cerebellum and brainstem. Both porencephaly and hydranencephaly can be secondary to vascular insult. DandyeWalker malformation classically describes the triad of cerebellar vermis hypoplasia, cystic dilatation of the fourth ventricle with enlargement of the posterior fossa.
bony lytic lesion. Cutaneous lesions vary from scaly papular rashes to flared vesicles. Biopsy will assist confirmation of the diagnosis. With reports of posterior pituitary dysfunction in up to 40% of cases, urine osmolality studies are recommended. Unless other symptoms are suggestive from the history, these investigations will suffice in single system disease. More extensive studies will be required for multisystem disease, including skeletal surveys and CT chest. Rarely, the GI tract may be involved. Reticuloendothelial disease carries a worse prognosis. The natural history of single bone lesions cannot be predicted. Some lesions resolve spontaneously, others regress after partial removal by biopsy and curettage. Occasionally, intra-lesional steroid injections are required. If all other therapies fail, 6m of low dose vincristine and oral steroids may be necessary. All patients should be followed up as recurrence is recognized. If this should occur, it usually involves the same system. In contrast, osteoid osteoma tends to provoke pain, more often at night. Osteoma is best demonstrated on CT with three distinct concentric zones e central nidus, fibrovascular rim and an outer reactive sclerosis. These are surgically resected or undergo radiofrequency ablation. Dermoid cysts generally occur along the midline and do not spontaneously resolve. Potts puffy tumour is an osteomyelitis of the frontal bone which may erode causing periosteal or intracranial abscess.
FURTHER READING Hahn JS, Plawner MD. Evaluation and management of children with holoprosencephaly. Pediatr Neurol 2004; 31: 79e88. Kauvar EF, Muenke M. Holoprosencephaly: recommendations for diagnosis and management. Curr Opin Pediatr 2010; 22: 687e95. Kurtz AB, Johnston PT. Case 7: hydranencephaly. Radiology 1999; 210: 419e22. www.radiopaedia.org.
Case 2 (a) iii (b) ii (c) v
FURTHER READING Windebank K, Nanduri V. Langerhans cell histiocytosis. Arch Dis Child 2009; 94: 904e908.
Explanation CT confirms a lytic lesion involving both the inner and outer skull tables with associated soft tissue mass. This appearance is consistent with Langerhans Cell Histiocytosis (LCH), whereas a pepper pot skull signifies multiple punched-out lesions associated with myeloma. Wormian bones are small extra intrasutural bones that maybe found around the lambdoid suture, associated with Osteogenesis Imperfecta. Epidermal cysts are common, well circumscribed cutaneous lesions that lie in or just beneath the skin. LCH is a rare condition with monoclonal proliferation of epidermal Langerhan cells characterized by the Birbeck granule. These act as antigen-presenting cells within the skin. The precipitating cause remains unknown. Manifestations of LCH are extremely diverse, and therefore categorized either as single system or multisystem disease, depending upon organ involvement. Annual incidence in the UK is estimated to be 4 per million children. Those diagnosed with single system disease tend to be older (more than 5), whereas, infants more frequently present with skin/pulmonary concerns. Skeletal disease is the most commonly affected system, the skull in particular. Typical presentation is of a painless, fluctuant swelling. Other sites can include orbital, vertebral and long bones. Imaging reveals the typical punched-out
PAEDIATRICS AND CHILD HEALTH 22:1
Case 3 (a) v (b) i Explanation WolffeParkinsoneWhite (WPW) is an AV re-entry tachycardia, caused by the presence of an accessory atrioventricular connection. Prevalence in children is estimated to be 0.1e0.2% more frequently seen in boys than girls. Approximately 0.5% of children with WPW have preexisting congenital cardiac disease. The typical ECG changes described in WPW consist of a shortened PR interval and widened QRS complex which shows a distinctive slurring of the initial portion of the r wave, known as the ‘delta’ wave. These morphological features are collectively referred to as ventricular preexcitation and normally seen when the patient is not in SVT. Atrial fibrillation is a recognized complication even in paediatric cases (5e10%). This increases the risk of sudden cardiac death, where rapid conduction over the accessory pathway can result in ventricular fibrillation. WPW can be differentiated from first degree heart block where the ECG would show a prolonged PR interval. Sinus arrhythmia is often seen as a variation of PeP interval
45
Ó 2011 Elsevier Ltd. All rights reserved.
SELF-ASSESSMENT
Case 4 (a) iii (b) i
V: Vertebral anomalies A: Anal anomalies C: Cardiac anomalies T-E: trachea-(o)esophageal abnormalities R: Renal/radius anomalies L: Limb anomalies Approximately 75% of patients will have congenital cardiac disease, most commonly VSD. Hypoplastic or hemi-vertebrae and trachea-oesophageal fistula may both feature in up to 70% of cases. Common limb defects include absent thumbs, polydactyly and forearm defects. Some reports suggest upper limb defects indicate a higher specificity for VACTERL. It is not uncommon to observe asymmetric abnormalities of the limbs. Anal atresia or imperforate anus is seen in approximately 55% of patients, single umbilical artery is not uncommon and 22% have cystic renal disease. No causative factor, genetic or environmental, has yet to be identified for VACTERL. HolteOram Syndrome is an AD inherited syndrome linked with TBX5 gene mutation resulting in heart-upper limb defects. TAR syndrome is distinguished by episodic periods of thrombocytopenia, particularly during infancy, and from varying degrees of hypoplasia, syndactyly or aplasia of the upper limb. TAR is associated with 1q21.1 microdeletions. Fanconi’s anaemia is a rare inherited syndrome of bone marrow failure associated with birth defects including thumb/radial malformation and skin hyperpigmentation. Chromosomal fragility testing assists this diagnosis. Case reports have described distal limb anomalies as a result of cocaine exposure in-utero, however, due to polysubstance mis-use, these are often difficult to attribute to cocaine alone.
Explanation The CXR demonstrates amelia of the left limb, absent right radius and vertebral anomalies. In conjunction with the cardiac defect, these features suggest VACTERL association. VACTERL refers to an association characterized of seemingly non-random pattern of malformations which together are not recognizable of a defined syndrome. Any combination of at least three of the following should prompt the paediatric team to consider the possibility of VACTERL:
FURTHER READING Castori M, Rinaldi R, Cappellacci S, Grammatico P. Tibial developmental field defect is the most common lower limb malformation pattern in VACTERL association. Am J Med Genet Part A 2010; 146A: p1259e66. http://www.vacterl-association.org.uk. Rittler M, Paz JE, Castilla EE. VACTERL association, epidemiological definition and delineation. Am J Med Genet 1996; 63: 529e36.
associated with respiration. Ventricular ectopics are early, broad QRS complexes produced by a premature ventricular ectopic discharge. Patients with Jervell and Lange-Nielsen Syndrome have markedly prolonged QT intervals and congenital deafness. Sudden death may be the first clinical manifestation of WPW. Up to 10% of asymptomatic WPW patients may experience potentially life-threatening arrhythmias, therefore, sitting back and continuing everyday life is not an option. It is recommended to treat symptomatic patients with antiarrhythmics until electrophysiology tests and RF-ablation can be performed. Iv Adenosine is used to attempt initial cardioversion in SVT. This may only achieve transient success but time enough to possibly capture the delta wave. Flecainide is a Class IC anti-arrhythmic (Naþ channel blocker) which reduces conduction through the accessory pathway. Side effects include a metallic taste and proarrhythmias. RF-ablation is reported to be successful in up to 95% of cases but the timing of procedure varies between centres.
FURTHER READING Dubin A. Cardiac arrhythmias. Section 4. In: Kliegman RM, Behrman RE, eds. Nelson textbook of paediatrics. 18th Edn. Philedelphia: Saunders WB, 2007; 1945-1946. Nunez F, Ruiz-Granell R, Martı´nez-Costa C, Morell S, Brines J. Safety and efficacy of flecainide in the treatment of symptomatic children with WolffeParkinsoneWhite syndrome. Pediatr Cardiol 2010; 31: 1162e65.
PAEDIATRICS AND CHILD HEALTH 22:1
46
Ó 2011 Elsevier Ltd. All rights reserved.