Background: Coeliac disease is frequently underdiagnosed because of its protean presentations. Serological tests may be helpful in screening programmes for populations at risk, but they are costly.
Aim: To determine prospectively whether a commonly available haematological test such as the red cell distribution width (RDW) could be of help in detecting unrecognized coeliac disease.
Methods: Of 353 consecutive adult patients referred to our outpatient malabsorption clinic, 198 in whom clinical suspicion was strong were referred for further investigations and intestinal biopsy. Seventy-six inflammatory bowel disease outpatients and 90 subjects admitted for diseases other than malabsorption were enrolled as the control group.
Results: RDW was increased in 94 (47.4%) and normal in 104 (52.5%) of 198 patients. Duodenal biopsy confirmed coeliac disease in 80 (85.1%) of the former patients and 69 (66.3%) of the latter patients. No correlation between RDW values and histological scores was found. Overall RDW increase was found in 80/149 (53.7%) patients with a definite diagnosis of coeliac disease, and in 14/49 (28.6%) patients in whom biopsy excluded the disease. A 1-year gluten withdrawal led to a significant decrease in RDW value, even in patients with obdurate mucosal impairment.
Conclusions: In patients in whom there is a strong clinical suspicion of coeliac disease, an elevated RDW despite normal haemoglobin concentration may be a reliable predictor of the disease.