INFLUENCE OF TOTAL COLECTOMY ON SERUM ANTINEUTROPHIL CYTOPLASMIC ANTIBODIES IN INFLAMMATORY BOWEL-DISEASE

Perinuclear antineutrophil cytoplasmic antibodies (pANCAs) have previo usly been demonstrated in patients with various forms of vasculitis an d more recently in those with inflammatory bowel disease (IBD) by an i ndirect immunofluorescence technique. Sera from 194 patients were test ed for pANCAs: 101 with ulcerative colitis (43 with varying grades of disease severity, 19 after subtotal colectomy, 39 following restorativ e proctocolectomy), 40 with Crohn's disease, five with indeterminate c olitis, 24 patients without IBD and 24 healthy volunteers (controls). The overall prevalence of pANCAs in patients with ulcerative colitis w as 70.3 per cent (71 of 101). These antibodies were still present in 2 9 of 39 patients after restorative proctocolectomy, in whom the median follow-up after surgery was 2 years. All five patients who had pouchi tis after restorative proctocolectomy were pANCA positive. By contrast , only ten of 40 patients with Crohn's disease had pANCAs, nine of who m had Crohn's colitis. No pANCAs were detected in controls. These resu lts show that pANCAs are more prevalent in colonic IBD, especially ulc erative colitis. The persistence of pANCAs in the sera for 2 years aft er restorative proctocolectomy suggests that the antigens are not full y eradicated and, therefore, that it is not just the colon that is tar geted immunologically in ulcerative colitis.