Coinfection by and in a captive adult diamondback water snake causing disseminated mycobacteriosis with acute cutaneous ulceration.

An adult male captive diamondback water snake () was found dead after a 1-d history of lethargy and cutaneous ulcers. The snake had eaten 2 sunfish ( spp.) 5 d before death. Gross examination revealed white-to-tan nodules in the lung and liver and segmental intestinal impactions with digested fish. Histopathology confirmed disseminated granulomas with numerous intrahistiocytic acid-fast bacteria in the skin, skeletal muscle, lung, liver, and intestines. and were identified by culture of the hepatic granuloma, followed by PCR and gene sequencing. To our knowledge, this is the first description of and coinfection in this species. Although has been isolated from reptiles, lesions associated with its presence in tissues have not been described previously. Interestingly, the mineralization within granulomas that we observed in our case is not reported in mycobacterial infection in reptiles, whereas this finding is common in mammals.