Chronic Multifocal Osteomyelitis - Is Mycobacterium avium Complex Really the Culprit? A Case Report in an Adult Female.

Introduction: There are reports which describe multiple lytic lesions seen on X-ray resulting from a non-tuberculous Mycobacterium skeletal infection in immunocompetent adults and children. AdditionallyIn addition, similar multifocal lesions have also been described in chronic recurrent multifocal osteomyelitis (CRMO) which is more common in children but has have rarely been reported in adults. We present a case of a 47-year-old female who presented with multiple osteolytic lesions and discuss how her diagnosis overlaps with CRMO and multifocal non-tuberculous osteomyelitis associated with Mycobacterium avium complex (MAC). Case Report: A 47-year-old female presented with a mass at her left sternoclavicular joint. Biopsy of the lesion showed acute and chronic inflammation suggesting osteomyelitis. The patient was on intravenousIV antibiotics with some improvement. After three 3 ½ and a half months, she was having knee pain and imaging showed another lesion and a bone scan found a third. Delayed cultures grew Mycobacterium avium complexMAC but ultimately the patient improved when she was taking naproxen for multifocal osteomyelitis. Conclusion: Multifocal lytic lesions on imaging in an adult can be multifocal osteomyelitis that, like in pediatric patients, may be treated best with nonsteroidal anti-inflammatory medications as with the patient in this case.