Escherichia coli‐associated granulomatous colitis in a cat

Abstract

A 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.

Repeat histopathology and culture of colonic biopsy specimens after treatment for Escherichia coli-associated granulomatous colitis in a cat

“…Similarly, we report the first description of culture and sensitivity profiling from colonic biopsy specimens alongside the fifth reported case of GC in a cat. [10][11][12][13] CR of GC relies upon eradicating intracellular E coli from within PAS+ macrophages in dogs and cats. [2][3][4][10][11][12][13] Antimicrobial resistance is a reported cause for relapsing canine GC with persistent clinical signs, histological changes and culture results.…”

“…[10][11][12][13] CR of GC relies upon eradicating intracellular E coli from within PAS+ macrophages in dogs and cats. [2][3][4][10][11][12][13] Antimicrobial resistance is a reported cause for relapsing canine GC with persistent clinical signs, histological changes and culture results. 3,14 In our case, E coli cultured after repeat colonic biopsies demonstrated the same susceptibility pattern without resistance, alongside a histological resolution of the GC.…”

“…[2][3][4] GC is rare in cats. [10][11][12][13] Direct colonic tissue culture is often used to guide antibiosis in dogs, but this has never been reported in a case of feline GC. Similarly, repeat histopathology and FISH performed on colonic biopsy specimens after fluoroquinolone treatment have not been described in cats.…”

Adherent-invasive Escherichia coli associated with granulomatous colitis and extraintestinal dissemination in a Sphynx cat

“… 6 , 10 , 19 To date, only 3 cases of GC in cats presumed to be caused by E. coli based on biopsy findings and response to antibiotic therapy are reported. 12 , 15 , 17 The diagnosis of CD and GC is based on characteristic mucosal ulceration accompanied by periodic acid-Schiff (PAS)-positive macrophages/histiocytes extending into the submucosa. Inflammation is described only in the colon of cats, while in people and dogs, the ileum, cecum, and mesenteric lymph nodes are compromised in variable degrees.…”

“…Inflammation is described only in the colon of cats, while in people and dogs, the ileum, cecum, and mesenteric lymph nodes are compromised in variable degrees. 12 , 13 , 15 , 17 , 19 Extraintestinal involvement, referred to as metastatic CD, occurs in up to 36% of affected humans with cutaneous and mucocutaneous granulomas being among the most common manifestations. 9 , 20 The role of AIEC in metastatic CD has not been explored and a metastatic form is not reported in dogs with GC.…”