Isolated CNS Nocardiosis in an Immunocompetent Patient

Introduction Nocardiosis is typically regarded as an opportunistic infection; risk factors For developing Nocardiosis include Diabetes, HIV infection (especially if CD4 count is <100), glucocorticoid therapy, transplantation, and malignancy (most often after recent hemotherapy). However; about one third of patients are immunocompetent; here, we present a case of Nocardiosis in an immunocompetent patient. Case presentation A 69 year old female with past medical history of COPD, Invasive ductal carcinoma of breast presented with progressive left sided weakness and headaches of one week duration. Initial evaluation was significant for left sided weakness in the upper and lower extremities along with left sided facial droop. CT brain without IV contrast revealed a ring enhancing mass measuring 2.4 mm * 2.8 mm in the right basal ganglia with significant adjacent edema, effacing the right lateral and third ventricles, and 2 mm leftward midline shift. Stereotactic biopsy of the brain mass identified it as an abscess and histology revealed acute and chronic inflammatory cells with no viable tissue. Gram stain and culture showed aerobic branching gram-positive organisms, which were later identified as Nocardia Farcinica. Discussion Although Nocardial brain abscess generally occurs in immunosupressed hosts, they were also reported in immunocompetent individuals. In immunosuppressed patients, involvement of the CNS should be ruled out even without neurologic symptoms.