Anaerobic Osteomyelitis in Children Rheumatic Fever and Poststrep Arthritis EDITORIAL BOARD Co-Editors: Margaret C

® CONCISE REVIEWS OF PEDIATRIC INFECTIOUS DISEASES

CONTENTS Anaerobic Osteomyelitis in Children Rheumatic Fever and Poststrep Arthritis EDITORIAL BOARD Co-Editors: Margaret C. Fisher, MD, and Gary D. Overturf, MD Editors for this Issue: Charles Woods, MD, and Jennifer Read, MD Board Members Michael Cappello, MD Barbara Jantausch, MD Jeffrey R. Starke, MD Ellen G. Chadwick, MD Charles T. Leach, MD Geoffrey A. Weinberg, MD Janet A. Englund, MD Kathleen McGann, MD Leonard Weiner, MD Leonard R. Krilov, MD Jennifer Read, MD Charles R. Woods, MD

Anaerobic Osteomyelitis in Children

Claudia M. Espinosa, MD,* Matthew M. Davis, MD, MAPP,† and Janet R. Gilsdorf, MD‡

Key Words: anaerobes, osteomyelitis hematogenous spread during bacteremia, an- with prosthetic and other orthopedic devices aerobic osteomyelitis usually results from may occur up to 24 months after surgery, or (Pediatr Infect Dis J 2011;30: 422–423) spread from a contiguous infection.1,2,8 Pro- even later.9,10 Foul odor of pus, once con- cesses that disrupt normal blood flow to the sidered a characteristic of anaerobic infec- 1,3,4,8 naerobic bacteria are a recognized cause bone, such as trauma, surgery, chronic or tions, is not always present. Complica- Aof osteomyelitis in children,1–7 and more acute ischemia, malignant growth, or met- tions of anaerobic osteomyelitis in children 3,4 abolic disorders, predispose to anaerobic are similar to those of aerobic osteomyelitis than 800 cases have been reported. Yet, 8 the prevalence of anaerobic osteomyelitis is bacterial replication. In children, conditions and include progression to chronic infection, unknown, in part because of the technical associated with anaerobic osteomyelitis in- deformity, and pathologic fracture. difficulties in isolating and identifying many clude mastoiditis, otitis media, sinusitis, periodontal abscess, human bites, decubitus of these organisms. The most common an- Diagnosis aerobic isolates reported in children with ulcers, ischemia (necrotic tissue), and, less 1,3–5 Isolation of anaerobic microorganisms osteomyelitis are Bacteroides spp. group, ac- frequently, trauma and diabetes mellitus. from bone tissue provides the definitive di- tinomycetes, Fusobacterium spp., anaerobic In general, causative agents of anaerobic agnosis of anaerobic osteomyelitis. Use of Gram positive organisms, Clostridium spp., osteomyelitis belong to mucous membrane anaerobic containers for collection and trans- Peptostreptococcus, Bacillus spp., Coryne- or skin flora contiguous to the infected site. port and fresh culture media, avoidance of bacterium spp., and, more recently, Pre- For example, skull and hand infections and votella spp., Porphyromonas spp., and Pro- those associated with human bites reflect oral contamination with normal flora, and rapid mucosa pathogens and perianal infections processing of the sample maximize recov- pionibacterium spp. (especially associated 3,4 1–4 with orthopedic devices).1–5,7–10 reflect gastrointestinal flora. ery. Because anaerobic organisms exhibit Polymicrobial infections and coin- variable sensitivity to oxygen tension, sub- fection with aerobic bacteria, common in culturing may be necessary for species PATHOGENESIS anaerobic osteomyelitis, are associated identification.3,4,8 Although osteomyelitis caused by aer- with increased severity and with treatment Identification and resistance testing of obic bacteria in children usually results from failure.1,3,8,11 A possible explanation is that anaerobes are not routine in all laboratories aerobic bacteria metabolize available oxy- due to cost and lack of standardization of the 13 From the *Division of General Pediatrics, University of gen, thus reducing the tissue oxidation po- methods. Antibiotic discs and spot tests Michigan Medical School, Ann Arbor, MI and tential to a level that allows anaerobic bac- may yield presumptive identification, but de- Child Health Evaluation And Research Unit, Divi- teria to grow.8 finitive identification may require biochemi- sion of General Pediatrics, University of Michigan, cal testing, low-molecular-weight fatty acid Ann Arbor, MI; †Child Health Evaluation And Re- search Unit, Division of General Pediatrics, Univer- Clinical Manifestations and profiling, or 16S rRNA sequencing. Identifi- sity of Michigan, Ann Arbor, MI and Division of Complications cation kits that require a shorter incubation General Medicine and Gerald R. Ford School of Anerobic osteomyelitis may be period in an aerobic environment (preformed Public Policy, University of Michigan, Ann Arbor, 1,7,8,12 enzymes) or longer incubation in an anaero- MI; and ‡Department of Epidemiology, University of asymptomatic. In a series of 26 pedi- Michigan School of Public Health, Ann Arbor, MI. atric patients, the duration of symptoms be- bic environment (inducible enzymes) have Supported by Eunice Kennedy Shriver National Insti- fore diagnosis varied widely from 7 to 37 good sensitivity (78%–79%).13 Matrix-as- tute of Child Health and Human Development days. Systemic symptoms, however, includ- sisted laser desorption/ionization time-of- (T32 HD007534) (to C.M.E.). flight mass spectrometry provides accurate Copyright © 2011 by Lippincott Williams & Wilkins ing low grade fever and localized pain, were ISSN: 0891-3668/11/3005-0422 found in 69% and 85% of cases, respec- and rapid identification for commonly iso- DOI: 10.1097/INF.0b013e318217ca0e tively, at admission.3 Infections associated lated anaerobic bacteria such as Bacteroides

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(identifies up to 97.5%), Fusobacterium, and acute or chronic. Most experts recommend 4 susceptibility patterns, and targeting the Prevotella.13 to 6 weeks for acute osteomyelitis. Treat- treatment to specific organisms when possi- When bone tissue is not available for ment of chronic osteomyelitis is more vari- ble will improve the outcome of anaerobic anaerobic culture, blood culture, and anaer- able, ranging from 4 weeks to more than 6 bone infection in children. obic culture of infected fluid contiguous to months10 after debridement of devitalized bone may yield the infecting organism. Sim- tissue. Empiric therapy should be directed to ilar to aerobic osteomyelitis, leukocytosis, major aerobic and anaerobic organisms, de- ACKNOWLEDGMENTS and elevated sedimentation rate and C-reac- pending on the site of the infection and the Claudia Espinosa, MD, thanks the tive protein values support the diagnosis, as local patterns of microbial resistance. Tran- Michigan Institute for Clinical and Health do radiographs showing periosteal new bone sition to oral therapy is acceptable after in- Research for a Clinical and Translational formation (imitating malignant bone tu- flammatory signs subside. Science Award. mors), but these changes occur after 2 Increasingly many anaerobic bacteria weeks.8 Radionuclide scanning with techne- produce beta-lactamase, limiting the thera- tium may be positive before standard radio- peutic value of penicillin. In such infections, REFERENCES graphic changes appear and may localize an beta-lactams with beta-lactamase inhibitors 1. Lewis RP, et al. Bone infections. Medicine (Bal- infection.14 Ultrasound has high sensitivity or antibiotics such as clindamycin, cefoxitin, timore). 1978;57:279–305. in detecting subperiosteal and soft-tissue a carbapenem, or metronidazole are indi- 2. Finegold SM, et al. Anaerobic infections. Part II. fluid collections. Computed tomography cated.4 Recently, resistance of anaerobes to Dis Mon. 1985;31:1–97. scanning is useful if bone sequestrum is amoxicillin/clavulanate and piperacillin/ta- 3. Brook I. Anaerobic osteomyelitis …. Pediatr In- present or if the anatomic site is difficult to zobactam (2%–11% of cases); cefoxitin fect Dis. 1986;5:550–556. assess with magnetic resonance imaging (ie, (3%–17%); and clindamycin (10%–40%), 4. Brook I. Joint and bone infections …. Pediatr Rehabil. 2002;5:11–19. evaluation of the pelvis or scapula). On the depending on the organism and geographic 13 5. Raff MJ, et al. Anaerobic osteomyelitis. Medicine other hand, magnetic resonance imaging has area, has been reported. Quinolones, (Baltimore). 1978;57:83–103. high sensitivity (82%–100%) and specificity widely used in adults, have not been well 6. Pichichero ME, et al. Polymicrobial osteomyelitis …. (75%–96%) if symptoms are localized, as- studied in the pediatric population. Thus, Rev Infect Dis. 1982;4:86–96. sesses the extent of soft-tissue compromise, they are not licensed for use in children, but 7. Nakata MM, et al. Anaerobic bacteria in bone …. and helps to differentiate acute from chronic have been shown in clinical practice to be Rev Infect Dis. 1984;6(suppl 1):S165–S170. 4,14 15 osteomyelitis. Evidence of bone necrosis safe. In general, clindamycin, vancomycin, 8. Ogden JA, et al. Pediatric osteomyelitis: III. Clin or abscess formation on imaging studies sug- and linezolid have excellent bone concen- Orthop Relat Res. 1979:230–236. gests possible anaerobic infection. trations, target some anaerobic bacteria 9. Templeton WC, et al. Anaerobic osteomyelitis …. and can be used as initial empiric therapy.4 Rev Infect Dis. 1983;5:692–712. Treatment Once culture and susceptibility test results 10. Ramos OM. Chronic osteomyelitis in children. Treatment of anaerobic osteomyelitis are available, antibiotic treatment should Pediatr Infect Dis J. 2002;21:431–432. includes management of pain, immobiliza- be tailored. 11. Hall BB, et al. Anaerobic osteomyelitis. J Bone tion, adequate drainage of purulent or ne- Joint Surg Am. 1983;65:30–35. crotic material (if present), and antibiotic CONCLUSION 12. Waldvogel FA, et al. Osteomyelitis: the past decade. N Engl J Med. 1980;303:360–370. therapy. Surgical debridement is required for Bone infections in children caused by 13. Nagy E. Anaerobic infections …. Drugs. 2010; patients with bony abscesses, necrotic bone, anaerobic bacteria have been diagnosed 70:841–858. decubitus ulcers, poor response to antimicro- more frequently in recent years due to im- 14. Karmazyn B. Imaging approach to acute hema- bial therapy, or an infected foreign body, or provements in bacterial isolation techniques togenous osteomyelitis. Semin Ultrasound CT 1–4 orthopedic device. The appropriate length and increased awareness. Attention to the MR. 2010;31:100–106. of antibiotic therapy remains controversial risk factors for anaerobic bacteria, use of 15. Schaad UB. Use of the new quinolones in pedi- and depends on whether the infection is standardized isolation methods, monitoring atrics. Isr J Med Sci. 1994;30:463–468.