Matthew R. Wanner MD, Presenter: Nothing to Disclose

Kelly Vanderhave MD, BS, Abstract Co-Author: Nothing to Disclose

John Lubicky MD, Abstract Co-Author: Nothing to Disclose

Boaz Karmazyn MD, Abstract Co-Author: Researcher, Siemens AG

To describe the clinical and imaging characteristics as well as complications of CA-MRSA musculoskeletal infections in children.

After obtaining IRB approval, we retrospectively reviewed the medical records of 27 children diagnosed with CA-MRSA musculoskeletal infections from 2 institutions from 2000-2008. Only children without any underlying disease were included. Data compiled from each patient included age, gender, presence of recent trauma, temperature at presentation, site(s) of involvement, imaging workup and findings, laboratory data, number of surgical interventions required, and other complications.

27 children (18 males, 9 females) with an average age of 9.3 years (range of 3 months to 17.7 years) were included. All of the patients were previously healthy. 9 children (33%) had minor trauma antecedent to the infection. 21 patients (78%) had a fever over 38 degrees at presentation. Laboratory Studies The WBC count was over 12,000 in 14 patients (52%) with a mean of 15,300. 16 of 23 patients (70%) had ESR over 40, with the mean ESR 72. Every patient had either a positive blood or wound culture (or both).  Blood cultures were positive in 16 children (59%) and wound cultures positive in 21 (78%). Imaging Initial x-rays at the symptomatic location(s) were negative in 21 patients (78%). 21 patients received additional imaging with MRI and 7 with bone scan. Osteomyelitis was found in 19 patients (70%), septic arthritis in 12 (44%), pyomyositis in 16 (59%), and abscess in 20 (74%). Infection was found to be multifocal (involving separate body parts) in 13 patients (48%). Deep venous thrombosis (DVT) was found in 7 patients (26%) and septic pulmonary emboli also seen in 7 patients (26%). 6 of the patients with septic PE were in the group with DVT. Surgical Intervention All patients required surgical intervention and 16 of 27 required multiple procedures. Patients received an average of 2.4 debridements.

Our experience demonstrates that CA-MRSA can affect healthy children, sometimes following minor trauma. Multifocal involvement is common, repeat I&D is frequently required, and roughly 25% in our cohort developed DVT and septic pulmonary emboli.

Knowing the associations of CA-MRSA musculoskeletal infections in children with multifocal involvement, DVT, and septic pulmonary emboli should help enable diagnosis and recognition of complications.

Wanner, M, Vanderhave, K, Lubicky, J, Karmazyn, B, Community Acquired Methacillin-Resistant Staphylococcus Aureus (CA-MRSA) Musculoskeletal Infection in 27 Children: Two Center Experience.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8005805.html