Mycobacterium pinnipedii in a captive Southern sea lion (Otaria flavescens): a case report

Mycobacterium pinnipedii causes tuberculosis in free-living and captive pinniped species throughout the world. We report on the isolation of this M. tuberculosis complex (MTC) member from an imported male Southern sea lion (Otaria flavescens) in a zoo in the Czech Republic. Nodular granulomatous lesions were found in the lungs, pleura and mesenteric lymph nodes of this animal and M. pinnipedii was isolated from lung, mesenteric and submandibular lymph nodes. Identification of the isolates was confirmed using two independent molecular methods. Direct IS6110 PCR amplification confirmed the presence of an MTC member in these samples. Faecal and oral swabs from three living female sea lions were examined using direct IS6110 PCR and were all found to be negative. Twelve environmental samples were examined using direct microscopy after Ziehl-Neelsen staining and culture methods along with direct IS6110 PCR examination, all yielding negative results. Seven people that came into close contact with the infected animal were examined using a skin tuberculin test and chest x-ray, revealing no evidence of infection by a MTC member.