Preliminary evaluation of the role of faecal calprotectin in the diagnosis of ulcerative colitis among Egyptian patients

ABSTRACT

Calprotectin, a member of the Ca2+-binding S100 family of proteins, makes up about 5% of the total protein content of the neutrophil. It is released upon activation and degranulation of neutrophils and correlates strongly with 111-indium-labeled leukocyte excretion. It was investigated as a promising tool in differentiating between Irritable Bowel syndrome [IBS] and active Inflammatory Bowel Disease [IBD]. Is to compare faecal Calprotectin in patients known to have ulcerative colitis with normal healthy controls and to investigate possible correlation of Calprotectin with disease activity on clinical, laboratory and pathological bases. Forty patients known to have UC were assessed. 19 were excluded 10 due to non-steroidal anti-inflammatory [NSAID] intake, 2 due to pregnancy and 7 due to disease quiescence. So, 21 patients with active disease were studied, 7 males [33.3%] and 14 females [66.7%], mean age 37.5 [ +/- 16.0] years. Ten healthy controls [8 females and 2 males], mean age 30.9 [ +/- 16.1] years were included. Patients underwent clinical evaluation, determination of blood Erythrocyte sedimentation rate [ESR], C-reactive protein [CRP] and faecal Calprotectin. Colonoscopy was done to confirm diagnosis, estimate disease extent and obtain colonoscopic biopsy specimens for histological grading of activity. An overall scoring of disease activity was done using the Mayo score. Faecal Calprotectin was significantly elevated among patients [mean 12.6 micro gm/gm stools [ +/- 3.2] in comparison to controls [9.4 micro gm/gm stools [ +/- 2.6], [p 0.01]. At a cut off of l0.3micro gm/gm stools it has a sensitivity of 86%.specificity of 70% p=0.004, positive predictive value of 86% and a negative predictive value of 70%. No correlation was found between faecal Calprotectin and ESR, histopathology and Mayo score. Calprotectin was significantly higher in cases with left sided colitis [l4.1 +/- 2.71gm/gm stools] than those with pnco1itis [11.8 +/- l.9 micro gm/gm stools], p 0.02.Faecal Calprotectin is a good test in differentiating Egyptian patients with ulcerative colitis from healthy controls. Thus, its use as a screening test may be helpful in the selection of cases for endoscopic examination. It lacks specific correlation with the severity of ulcerative colitis. This leaves endoscopy and histopathologic examinations as the main diagnostic tools. Larger scale studies on Egyptian patients are strongly recommended with special reference to the local mucosal permeability and immune milieu of the Egyptian population