PERINUCLEAR ANTINEUTROPHIL CYTOPLASMIC ANTIBODY AND REFRACTORY POUCHITIS - A CASE-CONTROL STUDY

Refractory pouchitis (RP) is a debilitating complication of heal pouch reservoirs that affects approximately 2.5% of patients. Although the cause of RP is unknown, it is frequently hypothesized that it reflects underlying Crohn's disease. Since perinuclear anti-neutrophil cytopla smic antibody (pANCA) is found in approximately 70% of ulcerative coli tis patients but only rarely in Crohn's disease patients, it may help distinguish Crohn's disease from ulcerative colitis. Therefore, to tes t whether RP reflects ''missed'' Crohn's disease, we determined the AN CA status of 26 patients with RP. The pANCA was positive in 42% of cas es [50% of Kock pouch cases and 33% of ileoanal pull-through (IAPT) ca ses] and 57% of matched control subjects without pouchitis (N = 42, P = NS). Moreover, 3/6 (50%) of IAPT RP subjects whose signs and symptom s most suggested Crohn's disease tested positive for pANCA. When compa red to controls, IAPT cases exhibited significantly more preoperative extraintestinal manifestations (EIMs) of inflammatory bowel disease (P < 0.05). The presence of preoperative EIMs was 100% predictive of pos toperative EIMs (P < 0.05). Review of pouch biopsies from cases of RP revealed no pathognomonic histologic features of Crohn's disease. Thes e data confirm our previous suggestion that RP does not reflect underl ying Crohn's disease but may be associated with the EIMs of inflammato ry bowel disease.