The role of fecal calprotectin in the diagnosis of acute pouchitis following IPAA for ulcerative colitis: a systematic clinical review

Purpose Total proctocolectomy (TPC) with ileal pouch anal anastomosis (IPAA) is commonly performed for patients with refractory ulcerative colitis (UC). Pouchitis occurs in 20–50% of these patients. Fecal calprotectin is a biomarker that correlates well with the pouchitis disease activity index. However, its role in the diagnosis and management of acute pouchitis has not been thoroughly defined. The aim of this study is to review previously established cut-off values and contextualize the clinical utility of fecal calprotectin. Methods Search of Medline, EMBASE, CENTRAL, and PubMed was performed. Articles were eligible if they measured fecal calprotectin in the setting of pouchitis in patients who underwent TPC with IPAA for UC. Risk of bias of the included studies was evaluated with the QUADAS-2. Results From 117 relevant citations, seven studies with 256 patients (44.8% female, 39.88 years) met inclusion criteria. The pooled prevalence of pouchitis was 42%. The derived fecal calprotectin cut-off values ranged from 56 to 494 μg/g. The corresponding sensitivities and specificities ranged from 57 to 100% and 38 to 92%, respectively. The area under the curve was reported in three studies and ranged from 0.832 to 0.840. Conclusion Fecal calprotectin may be a reliable diagnostic tool for acute pouchitis in patients following TPC with IPAA for UC. The high sensitivity of fecal calprotectin for detection of pouchitis makes it a valuable test for ruling out pouchitis. When used in conjunction with other biomarkers, the high specificity offers value in ruling in pouchitis. However, given the complexity of this disease process, relying solely on biomarkers for diagnosis is currently unreasonable.