Diagnostic Performance of Faecal Calprotectin among People with Chronic Inflammatory Diseases of the Bowel in Cameroon: A Pilot Study in Sub-Saharan Africa

Background: Inflammatory bowel diseases (IBDs) are relatively common in African countries. The use of faecal markers, Calprotectin in particular, is presently of considerable interest to IBD patients. The high faecal calprotectin level has a good diagnostic accuracy in discriminating intestinal organic and functional diseases and enables the selection of patients in need of other invasive diagnosis such as endoscopy.

Aim: To evaluate the diagnostic performance of faecal calprotectin as a useful diagnostic tool for IBD patients in Cameroon.

Study design: This was a case control cross-sectional multicentre study conducted in major gastroenterology units of the towns of Yaoundé and Douala involving 64 participants grouped as 32 IBD positive subjects and 32 IBD negative subjects.

Methods: Stool sample collected from participants at various recruitment sites were collected, conditioned and transported to the CIAB laboratory for analysis using a direct ELISA method. The R software was used for data analysis.

Results: The calprotectin levels of IBD patients were significantly higher than those of the control subjects (P < .001.) The area under the curve (AUC) was 0.96 [95%CI: 0.92 – 1.00; P < .001]. A threshold value of 2.51µg/g was chosen to exclude the diagnosis of IBD with an 87.5% sensitivity and 100% specificity. The CRP levels correlated with those of calprotectin (r꞊0.579, P ꞊ .005). Calprotectin concentrations became abnormally elevated in all UC patients with an Endoscopy Score greater than or equal to 6 (P = .001). Correlation between the endoscopy score for Crohn's disease and calprotectin concentration did not retain significance (ρ꞊0.800; P > .05).

Conclusion: Calprotectin dosage is a sensitive test for IBD, excludes unnecessary investigations and accurately predicts disease recurrence and response to treatment.