Pulmonary mycobacteriosis caused by Mycobacterium haemophilum and M. marinum in a royal python

An adult female royal python was referred with an 18-month history of chronic respiratory tract disease. Anemia and moderate leukocytosis with heterophilia and monocytosis were detected and interpreted as evidence of a chronic inflammatory condition. Evaluation of lateral and dorsoventral radiographic views revealed multiple soft-tissue opacities within the cranial lung fields. Endoscopic evaluation revealed that the normal reticulated pattern on the surface of the lung had been largely replaced by diffuse, granulomatous tissue. Histologic examination of biopsy specimens revealed classic pyogranulomas. Ziehl-Neelsen stains revealed numerous acid-fast bacilli consistent with Mycobacterium spp. Molecular methods including polymerase chain reaction restriction assays and DNA sequencing confirmed the identification of M. haemophilum and M. marinum. The snake was euthanatized. Mycobacteriosis is an uncommon and sporadic pyogranulomatous disease of reptiles. In most cases of reptile mycobacteriosis, treatment is not advised because of the chronic nature and often advanced stage of the disease, long-term and expensive nature of potential treatment regimens, and the risk of spread to other animals, including humans.