Inflammatory bowel disease: p-ANCA may help diagnose it.

Clinical bottom line (level 4)

  1. A positive p-ANCA made inflammatory bowel disease more likely, but a negative one could not exclude it.
Freeman et al: Canadian Journal of Gastroenterology 1997; 11 (3): 203-207
Expires May 2003

The study

Setting: university hospital, Canada

532 patients (aged ?, ?% male) 247 patients with ulcerative colitis. 253 patients with Crohn's disease. 32 patients with abdominal pain and diarrhoea found not to have inflammatory bowel disease (16 no disease, 15 infectious colitis, 1 ischaemic colitis)

Independent blinded reference standard, applied in all patients from a consecutive inappropriate spectrum.
Reference standard:
  • clinical features, radiology, endoscopy and histology positive for inflammatory bowel disease, and negative microbiological cultures
Diagnostic test: p-ANCA immunofluorescence assay confirmed on ELISA

The evidence


diagnostic test inflammatory bowel disease no inflammatory bowel disease LR+
(95% CI)		 LR-
(95% CI)
p-ANCA positive 194 0 inf
(4.3 to inf) 		0.61
(0.57 to 0.66)
total 500 32

Citation

  1. Freeman H, Roeck B, Devine D, et al: Prospective evaluation of neutrophil autoantibodies in 500 consecutive patients with inflammatory bowel disease. Canadian Journal of Gastroenterology 1997; 11 (3): 203-207
Contributor: Chris Ball and Clare Wotton, November 2000
Reviewer:

Clinical Question.
Patient ulcerative colitis, Crohn's disease, controls
Intervention or Exposure p-ANCA immunofluorescence
Outcome diagnosis of inflammatory bowel disease