Clinical Microbiology The First Korean Case of Disseminated Mycetoma Caused by Nocardia pseudobrasiliensis in a Patient on Long-Term Corticosteroid Therapy for the Treatment of

Nocardia pseudobrasiliensis is predominantly associated with invasive infections in immu-nocompromised patients. We report a case of disseminated mycetoma caused by N. pseudobrasiliensis in a 57-yr-old woman with microscopic polyangiitis, who was treated for 3 months with corticosteroids. The same organism was isolated from mycetoma cultures on the patient’s scalp, right arm, and right leg. The phenotypic characteristics of the iso-late were consistent with both Nocardia brasiliensis and N. pseudobrasiliensis, i.e., cata-lase and urease positivity, hydrolysis of esculin, gelatin, casein, hypoxanthine, and tyro-sine, but no hydrolysis of xanthine. The isolate was identified as N. pseudobrasiliensis based on 16S rRNA and hsp65 gene sequencing. The patient was treated for 5 days with intravenous ampicillin/sulbactam, at which time both the mycetomas and fever had sub-sided and discharged on amoxicillin/clavulanate. This case highlights a very rare presen-tation of mainly cutaneous mycetoma caused by N. pseudobrasiliensis. This is the first re-ported case of N. pseudobrasiliensis infection in Korea