C-reactive protein/albumin ratio (CAR) as a marker for detecting acute severe ulcerative colitis in Egyptian patients

The C-reactive protein/albumin ratio (CAR) is an inflammatory marker that is considered to have prognostic value in many diseases. Our aim in the present study was to investigate the diagnostic performance of the CAR in determining the clinical severity of acute severe ulcerative colitis (ASUC).

A retrospective study on 200 UC patients that were admitted to the Gastroenterology unit of the Alexandria University, over an 8-year period from January 2012 to January 2020, was conducted. Patient demographic data, laboratory values, and clinical and endoscopic disease activity scores were evaluated. C-reactive protein (CRP) and albumin levels were recorded. The CAR was calculated to determine clinical severity.

Of the 200 patients, 135 (67.5%) were men and 65 (32.5%) were women. Mean age was 43.5 ± 9.8 years. Patients were divided into groups with mild, moderate, or severe disease activity and there were statistically significant differences in the CAR, the erythrocyte sedimentation rate (ESR), CRP levels, and albumin levels (p = 0.001; p < 0.05). With a cut-off value of 0.6, the CAR performed best in defining patients with severe disease, with an area under the curve (AUC) of 0.985, 98% sensitivity, 100% specificity, positive predictive value (PPV) of 100%, and negative predictive value (NPV) of 97%, p < 0.001. AUC values for the diagnosis of severe disease were 0.985, 0.88, 0.72, and 0.65 for the CAR, CRP, albumin, and the ESR, respectively.

There was a statistically significant association between the CAR and clinical disease activity in patients with UC. The CAR is a reliable and practical tool for detecting ASUC.