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Parvimonas micra: A rare cause of native joint septic arthritis
Anaerobe 39 (2016) 26e27
Contents lists available at ScienceDirect
Anaerobe journal homepage: www.elsevier.com/locate/anaerobe
Case reports
Parvimonas micra: A rare cause of native joint septic arthritis Adam Baghban*, Shaili Gupta Yale University School of Medicine, United States
a r t i c l e i n f o
a b s t r a c t
Article history: Received 19 January 2016 Accepted 13 February 2016 Available online 18 February 2016
Parvimonas micra is a fastidious, anaerobic, gram positive coccus, which is found in normal human oral and gastrointestinal flora. It has also been known as Peptostreptococcus micros and Micromonas micros with its most recent re-classification in 2006. It has been described in association with hematogenous seeding of prosthetic joints [1,2]. Several cases of discitis and osteomyelitis have been described in association with dental procedures and periodontal disease often with a subacute presentation. However, cases of native joint septic arthritis are limited [3e5]. Per our literature review, there is one case of native knee septic arthritis described in 1999, with a prolonged time to diagnosis and treatment due to difficulty culturing P. micra. The previously reported patient experienced significant joint destruction and morbidity [6]. Advances in culture techniques and new methods of organism identification including MALDI-TOF and 16s rRNA sequencing have lead to increased identification of this organism, which may be a more frequent bone and joint pathogen than previously realized. Published by Elsevier Ltd.
Handling Editor: Elisabeth Nagy Keywords: Osteomyelitis Septic joint Knee Native Parvimonas Micromonas Peptostreptococcus
1. Case A 65-year-old man with well-controlled diabetes mellitus and bilateral knee osteoarthritis presented to the hospital with 3 weeks of gradually progressive left knee pain. He lived in the rural Northeastern United States, and frequently gardened outside, but denied trauma to the knee beyond kneeling in the garden. He had no recent procedures to the knee but he did report minor dental work 2 months prior to his presentation. He was evaluated by his primary care physician 2 weeks prior to presentation, was diagnosed with a muscle strain related to his gardening and given a trial of acetaminophen and rest. When symptoms progressed, he was referred to outpatient rheumatology and an arthrocentesis was performed. Fluid was described as hazy, with 19,154 nucleated cell count (93% neutrophils), 2000 RBCs, and rare negatively birefringent crystals. Initiation of steroids for pseudogout was deferred pending maturation of synovial fluid cultures. The patient began to experience subjective fevers over the next two days. Synovial fluid grew gram positive cocci after which patient was instructed to seek inpatient care. In the hospital, temperature was 38 C orally, and vitals were otherwise normal. His physical exam was notable for fair dentition,
* Corresponding author. E-mail address: [email protected] (A. Baghban). http://dx.doi.org/10.1016/j.anaerobe.2016.02.004 1075-9964/Published by Elsevier Ltd.
with some periodontal disease, and a left knee effusion, with the joint warm but not erythematous, and extremely painful with flexion and extension. Serum leukocyte count was 8,600, with 71.6% neutrophils. Synovial fluid cultures grew Parvimonas micra in the fluid aspirated prior to admission, and the patient was started on empiric clindamycin 600 mg intravenously every 8 h. A second arthrocentesis was pursued 3 days after the initial procedure, and revealed 23,255 nucleated cells (88% neutrophils) and 18,000 RBCs, a third on hospital day two revealed a nucleated cell count of 46,100 with 11,000 red blood cells. The second synovial fluid sample grew P. micra, five days after collection, and the third had gram positive cocci on gram stain but no growth. C-reactive protein was 295 mg/ L, ESR was 82 mm/h. MRI of the knee showed enhancement of suprapatellar bursal fluid and bone marrow enhancement in the medial femoral condyle and medial tibial plateau. Orthopaedic surgery was involved on admission; open irrigation and debridement was deferred initially due to relatively non-purulent synovial fluid. After his serial arthrocenteses demonstrated a rising cell count, patient underwent arthrotomy with irrigation and drainage. Turbid joint fluid and inflamed synovial tissue were noted. Multiple intraoperative tissue and fluid samples remained negative on cultures although many leukocytes were seen. Dental evaluation confirmed significant periodontal disease but no frank oral infection. Blood cultures were negative. Transthoracic echocardiogram was unremarkable and transesophageal echocardiogram was not pursued as the decision for prolonged treatment had already been
A. Baghban, S. Gupta / Anaerobe 39 (2016) 26e27
27
made based on MRI findings consistent with osteomyelitis contiguous to the joint space. Six weeks of intravenous therapy were completed, but he was changed halfway through his course to ampicillin/sulbactam due to a possible drug rash to clindamycin. Inflammatory markers normalized, with his most recent ESR 5 mm/ H and CRP 1.17 mg/L. Knee joint range of motion is intact, but he has continued to ambulate with a cane several months postpresentation. Of note, screening colonoscopy was performed after completion of rehabilitation, and was unremarkable.
arthrotomic drainage [7]. We ultimately found no source for this patient's septic knee other than periodontal disease and dental manipulation raising the point that obtaining this history may be enough to suggest a sub-acute anaerobic infection in the right clinical context. Identification of P. micra was aided by MALDI-TOF in this case. With increased availability of this modality a greater incidence of fastidious anaerobes like P. micra as bone and joint pathogens may be realized.
2. Discussion
References
This case highlights several important diagnostic and management issues in a patient with a fastidious anaerobic infection. The patient presented with a synovial fluid that was less cellular than that typically seen with more virulent organisms, which emphasizes that a low synovial fluid cell count cannot exclude an infected joint. Second, there was a significant delay to treatment, both prior to his hospitalization while he was developing progressive symptoms, and then subsequent to his admission after antibiotics were started but surgical debridement was deferred in lieu of serial aspirations due to low cell count. Data supporting this approach are limited to small retrospective reviews. While there is general consensus that intra-articular cartilage destruction from septic inflammation can be irreversible with resultant joint dysfunction, there are no prospective comparative outcome data on addressing this by serial needle aspiration compared to arthroscopic/
[1] H. Bartz, et al., Micromonas (Peptostreptococcus) micros: unusual case of prosthetic joint infection associated with dental procedures, Int. J. Med. Microbiol. 294 (7) (2005) 465e470. [2] T. Stoll, et al., Infection of a total knee joint prosthesis by peptostreptococcus micros and propionibacterium acnes in an elderly RA patient: implant salvage with longterm antibiotics and needle aspiration/irrigation, Clin. Rheumatol. 15 (4) (1996) 399e402. [3] I.A. George, A. Pande, S. Parsaei, Delayed infection with Parvimonas micra following spinal instrumentation, Anaerobe 35 (Pt B) (2015) 102e104. [4] B. Pilmis, et al., Spondylodiscitis due to anaerobic bacteria about a case of Parvimonas micra infection, Anaerobe 34 (2015) 156e157. [5] H. Uemura, et al., Parvimonas micra as a causative organism of spondylodiscitis: a report of two cases and a literature review, Int. J. Infect. Dis. 23 (2014) 53e55. [6] K. Riesbeck, L. Sanzen, Destructive knee joint infection caused by Peptostreptococcus micros: importance of early microbiological diagnosis, J. Clin. Microbiol. 37 (8) (1999) 2737e2739. [7] V. Ravindran, I. Logan, B.E. Bourke, Medical vs surgical treatment for the native joint in septic arthritis: a 6-year, single UK academic centre experience, Rheumatol. Oxf. 48 (10) (2009) 1320e1322.
Contents lists available at ScienceDirect
Anaerobe journal homepage: www.elsevier.com/locate/anaerobe
Case reports
Parvimonas micra: A rare cause of native joint septic arthritis Adam Baghban*, Shaili Gupta Yale University School of Medicine, United States
a r t i c l e i n f o
a b s t r a c t
Article history: Received 19 January 2016 Accepted 13 February 2016 Available online 18 February 2016
Parvimonas micra is a fastidious, anaerobic, gram positive coccus, which is found in normal human oral and gastrointestinal flora. It has also been known as Peptostreptococcus micros and Micromonas micros with its most recent re-classification in 2006. It has been described in association with hematogenous seeding of prosthetic joints [1,2]. Several cases of discitis and osteomyelitis have been described in association with dental procedures and periodontal disease often with a subacute presentation. However, cases of native joint septic arthritis are limited [3e5]. Per our literature review, there is one case of native knee septic arthritis described in 1999, with a prolonged time to diagnosis and treatment due to difficulty culturing P. micra. The previously reported patient experienced significant joint destruction and morbidity [6]. Advances in culture techniques and new methods of organism identification including MALDI-TOF and 16s rRNA sequencing have lead to increased identification of this organism, which may be a more frequent bone and joint pathogen than previously realized. Published by Elsevier Ltd.
Handling Editor: Elisabeth Nagy Keywords: Osteomyelitis Septic joint Knee Native Parvimonas Micromonas Peptostreptococcus
1. Case A 65-year-old man with well-controlled diabetes mellitus and bilateral knee osteoarthritis presented to the hospital with 3 weeks of gradually progressive left knee pain. He lived in the rural Northeastern United States, and frequently gardened outside, but denied trauma to the knee beyond kneeling in the garden. He had no recent procedures to the knee but he did report minor dental work 2 months prior to his presentation. He was evaluated by his primary care physician 2 weeks prior to presentation, was diagnosed with a muscle strain related to his gardening and given a trial of acetaminophen and rest. When symptoms progressed, he was referred to outpatient rheumatology and an arthrocentesis was performed. Fluid was described as hazy, with 19,154 nucleated cell count (93% neutrophils), 2000 RBCs, and rare negatively birefringent crystals. Initiation of steroids for pseudogout was deferred pending maturation of synovial fluid cultures. The patient began to experience subjective fevers over the next two days. Synovial fluid grew gram positive cocci after which patient was instructed to seek inpatient care. In the hospital, temperature was 38 C orally, and vitals were otherwise normal. His physical exam was notable for fair dentition,
* Corresponding author. E-mail address: [email protected] (A. Baghban). http://dx.doi.org/10.1016/j.anaerobe.2016.02.004 1075-9964/Published by Elsevier Ltd.
with some periodontal disease, and a left knee effusion, with the joint warm but not erythematous, and extremely painful with flexion and extension. Serum leukocyte count was 8,600, with 71.6% neutrophils. Synovial fluid cultures grew Parvimonas micra in the fluid aspirated prior to admission, and the patient was started on empiric clindamycin 600 mg intravenously every 8 h. A second arthrocentesis was pursued 3 days after the initial procedure, and revealed 23,255 nucleated cells (88% neutrophils) and 18,000 RBCs, a third on hospital day two revealed a nucleated cell count of 46,100 with 11,000 red blood cells. The second synovial fluid sample grew P. micra, five days after collection, and the third had gram positive cocci on gram stain but no growth. C-reactive protein was 295 mg/ L, ESR was 82 mm/h. MRI of the knee showed enhancement of suprapatellar bursal fluid and bone marrow enhancement in the medial femoral condyle and medial tibial plateau. Orthopaedic surgery was involved on admission; open irrigation and debridement was deferred initially due to relatively non-purulent synovial fluid. After his serial arthrocenteses demonstrated a rising cell count, patient underwent arthrotomy with irrigation and drainage. Turbid joint fluid and inflamed synovial tissue were noted. Multiple intraoperative tissue and fluid samples remained negative on cultures although many leukocytes were seen. Dental evaluation confirmed significant periodontal disease but no frank oral infection. Blood cultures were negative. Transthoracic echocardiogram was unremarkable and transesophageal echocardiogram was not pursued as the decision for prolonged treatment had already been
A. Baghban, S. Gupta / Anaerobe 39 (2016) 26e27
27
made based on MRI findings consistent with osteomyelitis contiguous to the joint space. Six weeks of intravenous therapy were completed, but he was changed halfway through his course to ampicillin/sulbactam due to a possible drug rash to clindamycin. Inflammatory markers normalized, with his most recent ESR 5 mm/ H and CRP 1.17 mg/L. Knee joint range of motion is intact, but he has continued to ambulate with a cane several months postpresentation. Of note, screening colonoscopy was performed after completion of rehabilitation, and was unremarkable.
arthrotomic drainage [7]. We ultimately found no source for this patient's septic knee other than periodontal disease and dental manipulation raising the point that obtaining this history may be enough to suggest a sub-acute anaerobic infection in the right clinical context. Identification of P. micra was aided by MALDI-TOF in this case. With increased availability of this modality a greater incidence of fastidious anaerobes like P. micra as bone and joint pathogens may be realized.
2. Discussion
References
This case highlights several important diagnostic and management issues in a patient with a fastidious anaerobic infection. The patient presented with a synovial fluid that was less cellular than that typically seen with more virulent organisms, which emphasizes that a low synovial fluid cell count cannot exclude an infected joint. Second, there was a significant delay to treatment, both prior to his hospitalization while he was developing progressive symptoms, and then subsequent to his admission after antibiotics were started but surgical debridement was deferred in lieu of serial aspirations due to low cell count. Data supporting this approach are limited to small retrospective reviews. While there is general consensus that intra-articular cartilage destruction from septic inflammation can be irreversible with resultant joint dysfunction, there are no prospective comparative outcome data on addressing this by serial needle aspiration compared to arthroscopic/
[1] H. Bartz, et al., Micromonas (Peptostreptococcus) micros: unusual case of prosthetic joint infection associated with dental procedures, Int. J. Med. Microbiol. 294 (7) (2005) 465e470. [2] T. Stoll, et al., Infection of a total knee joint prosthesis by peptostreptococcus micros and propionibacterium acnes in an elderly RA patient: implant salvage with longterm antibiotics and needle aspiration/irrigation, Clin. Rheumatol. 15 (4) (1996) 399e402. [3] I.A. George, A. Pande, S. Parsaei, Delayed infection with Parvimonas micra following spinal instrumentation, Anaerobe 35 (Pt B) (2015) 102e104. [4] B. Pilmis, et al., Spondylodiscitis due to anaerobic bacteria about a case of Parvimonas micra infection, Anaerobe 34 (2015) 156e157. [5] H. Uemura, et al., Parvimonas micra as a causative organism of spondylodiscitis: a report of two cases and a literature review, Int. J. Infect. Dis. 23 (2014) 53e55. [6] K. Riesbeck, L. Sanzen, Destructive knee joint infection caused by Peptostreptococcus micros: importance of early microbiological diagnosis, J. Clin. Microbiol. 37 (8) (1999) 2737e2739. [7] V. Ravindran, I. Logan, B.E. Bourke, Medical vs surgical treatment for the native joint in septic arthritis: a 6-year, single UK academic centre experience, Rheumatol. Oxf. 48 (10) (2009) 1320e1322.