A Rare Case of Disseminated Nocardia transvalensis in an Immunocompetent Host.

Background: Nocardia are a group of bacteria known to cause pulmonary, cutaneous, neurologic, or disseminated diseases, usually in immunocompromised hosts. Within the Nocardia family is Nocardia transvalensis, a rarely encountered and underreported organism in the clinical literature. Case: Here, we report the case of an immunocompetent patient presenting with lumbar pain diagnosed and treated for disseminated Nocardia transvalensis infection. Our patient underwent magnetic resonance imaging (MRI), demonstrating possible abscess and subtle osteomyelitis of the L3-L4 facet joint and transverse process; a subsequent biopsy and culture resulted in Nocardia transvalensis. Further imaging with a computed tomography (CT) scan of the head revealed a 9 mm enhancing supratentorial lesion. The patient was treated with empiric antibiotics, but this was narrowed to levofloxacin, linezolid, and trimethoprim-sulfamethoxazole after antibiotic sensitivities cropped up. Conclusions: Within this case, we extensively discuss the clinical pathogenesis of Nocardia transvalensis in an unusual host, the diagnostic approach to confirming active Nocardia infection, and the susceptibility patterns in a relatively unstudied organism.