Disseminated mycobacteriosis caused by Mycobacterium kansasii in a pot-bellied pig

Abstract

A 1.5-y-old spayed female Juliana pot-bellied pig was presented to the Purdue University Veterinary Teaching Hospital with a history of wasting and anorexia. Enlarged and partially mineralized lymph nodes were identified on radiographs and computed tomography scan. Generalized lymphadenomegaly and disseminated nodules in the lungs, liver, spleen, and kidneys were identified on postmortem examination. Histologic examination revealed caseonecrotic granulomas with numerous intracellular, acid-fast bacilli. Mycobacterium kansasii type II was identified as the etiologic agent by PCR amplification using universal Mycobacterium primers, direct sequencing of the PCR amplicon, and comparison to sequences in GenBank. We describe a case in a pot-bellied pig of mycobacteriosis caused by an atypical mycobacterial species and highlight the important role of laboratory testing in suspected cases of tuberculosis.