Ultrasonographic and histopathological features in 8 cats with fibrotic small intestinal stricture

Abstract

Benign stricture is an uncommon cause of chronic small intestinal obstruction in the cat. The purpose of this retrospective case series was to describe the ultrasonographic features, histopathological findings, and clinical presentation in a group of cats with benign small intestinal stricture. Inclusion criteria were cats presenting during the period 2010‐2017, and that had ultrasonography and small intestinal stricture confirmed at surgery. For each cat, clinical data and ultrasonographic findings were retrieved from the medical record, and histopathology, where available, was reviewed. Eight cats met the inclusion criteria. The location of strictures was duodenum (1/8), mid‐ to distal jejunum (4/8), and ileum (3/8). Ultrasonographic findings included gastric distension (8/8) and generalized (3/8) or segmental (5/8) intestinal dilation consistent with mechanical obstruction. Ingesta did not propagate beyond the strictured segment. Wall thickening was mild to moderate (3‐6 mm). Normal wall layering was disrupted in all cats. Strictures were predominantly hypoechoic (7/8) and associated with hyperechoic peri‐intestinal mesentery (6/8). Annular strictures (5/8) were less than 15 mm in length whereas long‐segment strictures (3/8) were greater than 15 mm in length. Histopathology showed transmural disease with fibrosis and inflammation (8/8), often (6/8) extending into the bordering mesentery. The mucosa was the most severely affected layer and epithelial injury accompanied the mucosal fibrosis/inflammation. Clinical presentation reflected delayed diagnosis of chronic bowel obstruction with debilitation (8/8), marked weight loss (8/8), and prerenal azotemia (5/8). Benign fibrostenotic stricture should be considered a differential diagnosis in debilitated young cats presenting with chronic bowel disease and ultrasonographic features of intestinal obstruction.

Feline abdominal ultrasonography: What’s normal? What’s abnormal? The diseased gastrointestinal tract

“…Ultrasonographically, strictures were characterised by a segment of bowel with a non-distensible lumen and were identified in the duodenum (1/8), mid- to distal jejunum (4/8) and proximal ileum (3/8). 70 In all cats, there was evidence of moderate to marked gastric and either generalised or segmental small intestinal distension oral to the stenosis indicative of mechanical bowel obstruction. The length of the stenosed segment varied from 2–50 mm.…”

“…Histopathology revealed transmural pathology, which was characterised by inflammation and marked fibrosis that affected the mucosal layer most severely. 70 Sections from three of the cats enabled the authors to demonstrate that fibrosis was indeed the main contributor to the narrowing of the intestinal lumen. Although the aetiology of the fibrosis in these cats is unknown, infectious agents and/or bowel ischaemia were suggested as potential underlying causes.…”

“…The ultrasonographic and histopathological features of benign fibrotic small intestinal strictures have recently been described in eight cats with chronic intestinal ob struction. 70 The ages of the cats ranged from 2-10 years. Clinical signs included intermittent vomiting, anorexia and severe lethargy.…”

Diagnostic utility of abdominal ultrasound for detecting non‐perforated gastroduodenal ulcers in dogs

“…29,30 In this study, thrombosis of the cranial mesenteric artery was observed during ultrasound in one dog. The CT features of arterial mesenteric thrombosis have been described in dogs with mucosal necrosis, 31 and ulcerative lesions associated with mesenteric thrombosis and intestinal ischaemia have been documented in cats using grey scale 32 and contrast-enhanced ultrasound. 33 However, in this patient, it is unlikely that thrombosis of the cranial mesenteric artery alone would be sufficient to cause duodenal ischaemia, as the duodenum receives mostly dual arterial supply from the cranial pancreaticoduodenal artery, a branch of the celiac artery and the caudal pancreaticoduodenal artery, a branch of the caudal mesenteric artery.…”