Nephrectomy in a Case of Infectious Nephritis in a Mexican Kingsnake (Lampropeltis getula nigrita)

A 10-year-old, intact, captive-born female Mexican black kingsnake (Lampropeltis getula nigrita) was presented with a 1-week history of caudal coelomic distention. On physical examination a 5 cm in length, soft nonmobile mass was identified in the caudal third of the coelomic cavity, 4 cm cranially to the cloaca. Survey radiographic images revealed an increased soft tissue opacity within the affected area with variable sized, irregular mineralized structures. An intracloacal contrast study showed contrast retention in the cloaca. The retention of contrast within the cloaca was compatible with the presence of a mass compressing the rectum. An ultrasound evaluation confirmed a 2 × 3 cm, oval, well-defined mass with an echogenic capsule. Computed tomographic imaging revealed a heterogeneous mass with some mineral areas with irregular shape and size. The mass was excised and the tissue submitted for histopathology and culture. The histopathological and microbiological diagnosis of the mass was purulent interstitial nephritis with presence of multiple histiocytic granulomas that contained intralesional bacteria (Morganella morganni). The animal responded well to the surgical removal of the mass and subsequent medical treatment.