IL-6 and CRP are superior in early differentiation between mild and non-mild acute pancreatitis

The revised Atlanta classification on acute pancreatitis (AP) presents distinct criteria for severity categorization. Due to the lack of reliable prognostic markers, a majority of patients with AP are currently hospitalized and initially managed identically. As incidence and financial costs are rising the need for early severity differentiation will increase. This study aimed to investigate the capacity of biomarkers to stratify AP patients during the initial course of the disease.

Patients with AP were prospectively enrolled and dichotomized into mild or non-mild (moderately severe and severe AP) according to the revised Atlanta classification. Serum samples taken within 13-36 h after onset of disease were analyzed for 20 biomarkers. Through receiver operating curves cut-off levels were set for 5 biomarkers whose stratifying ability was further analyzed. Additionally, the patients were classified according to the harmless acute pancreatitis score (HAPS).

Among the 175 patients, 70.9% had mild and 29.1% non-mild AP. CRP and IL-6 combined, with cut-off levels 57.0 and 23.6 respectively, demonstrated superior discriminative capacity with an area under the curve of 0.803, sensitivity 98%, specificity 54% and a positive and negative likelihood ratio of 2.1 and 0.06 for the non-mild group. Regarding the mild group likelihood ratios were positive 26.5 and negative 0.48. The identification potential of the HAPS was generally inferior when compared to CRP plus IL-6.

In this study CRP and IL-6 demonstrate a clinically relevant capacity to differentiate mild from non-mild AP early in the course of AP.