Osamuyimen Igbinosa^1,, Owen Igbinosa², Krishna Dass¹, Glenn Wortmann¹

Patients with T-cell defects are at the highest risk for nocardiosis, a potentially life-threatening infection caused by several species of the genus, Nocardia. We report a case of disseminated Nocardia arthritidis in a patient who had no recognizable risk factors for immunodeficiency. A 43-year-old woman was noted to have a left upper lobe cavitary lesion on an outpatient computerized tomography (CT) scan that was performed for evaluation of pelvic congestion syndrome. She subsequently had an image-guided biopsy of the lesion, but the results were still pending when she presented at the emergency department with a transient episode of aphasia. A CT scan of the patient’s head revealed hypodensities in the right frontoparietal and left frontal lobes. A modified acid-fast stain on the lung biopsy specimen demonstrated variable, branching, filamentous bacteria with morphology consistent with Nocardia species. Matrix-Assisted Laser Desorption / Ionization – Time-of-Flight (MALDI-TOF) Mass Spectrometry at a reference laboratory later identified the bacteria as Nocardia arthritidis. This case highlights that disseminated nocardiosis can occur in an apparently healthy population. A more detailed immunologic evaluation that include screening for chronic granulomatous disease, anticytokine autoantibody deficiency and interleukin-12-gamma interferon pathway deficiency may further assist in the diagnosis of patients’ underlying diseases.

Norcadiosis, Norcadia arthritidis Immunocompromised