Hematogenous Osteomyelitis by Acinetobacter Baumannii: Case Report and Literature Review

Skeletal infection with Acinetobacter baumanii is a rare condition and found mainly among soldiers injured in war. Multidrug resistant (MDR) Acinetobacter baumanii (A. baumanii) osteomyelitis is difficult to treat and requires long course of intravenous antibiotics. Most of reported cases in the literature are the consequences of direct inoculation of the pathogen. Here in, we report the first case of A. Baumannii osteomyelitis disseminated through hematogenous route and the therapeutic approach for this rare infection. Clinical Presentation: A 46 year old African-American male patient with human immunodeficiency virus (HIV) and end- stage renal disease on hemodialysis, who developed persistent MDR A. baumanii bacteremia in the hospital, thought to be secondary to the hemodialysis catheter, necessitating replacement of the catheter. Three months after his discharge to a skilled nursing facility (SNF), he developed left leg swelling without noticeable pain or fever. MRI revealed findings consistent with chronic osteomyelitis of left tibia and intra operative bone culture grew MDR A. baumannii. The patient had good outcome after three surgical debridements and prolonged period (7 Months) of dual antimicrobial therapy. Discussion: While in most documented cases of A. baumannii osteomyelitis, entry appears to require direct inoculation; our case suggests that this pathogen can seed into bone hematogenously in the setting of immunosuppression, persistent bacteremia and possibly in the presence of underlying bone infarcts. Clinicians need to be aware of this rare possible consequence of A. baumannii bacteremia. In conclusion, combination of multiple surgical debridements and dual antimicrobial therapy for a long period may result in a good outcome.