Escherichia coli‐associated granulomatous colitis in a cat

Abstract

AbstractA six‐year‐old male castrated domestic shorthair cat was evaluated for a six‐month history of haematochezia, mucoid diarrhoea, tenesmus and rectal prolapse. Colonic histopathology revealed multifocal mucosal ulceration and lamina propria infiltration with large numbers of periodic acid‐Schiff‐positive macrophages. Large clusters of intracellular Escherichia coli were confirmed with fluorescence in situ hybridization testing, similar to that seen in dogs with granulomatous colitis. An eight‐week course of marbofloxacin resulted in resolution of clinical signs; however, recurrence occurred four weeks later. A 12‐week course of marbofloxacin resulted in disease remission for which the cat still remains free of clinical signs (15 months). Escherichia coli‐associated granulomatous colitis, although reported with rarity in this species, is an important infectious cause of chronic large intestinal disease in the cat.