Diagnostic accuracy of interleukin-6 and interleukin-8 in predicting severe acute pancreatitis: a meta-analysis

The early identification of patients at risk for severe acute pancreatitis (SAP) is crucial. Serum markers of disease severity have been assessed including interleukin (IL)-6 and IL-8; however, their predictive accuracy has varied significantly across studies. We conducted a meta-analysis to assess the accuracy of IL-6 and IL-8 at predicting SAP.

We identified relevant published articles and calculated pooled sensitivities, specificities and likelihood ratios using the random-effect model. We included values for days 1, 2 and 3 of presentation for IL-6 and for days 1 and 2 for IL-8. We also constructed summary receiver-operating curves and assessed the area under the curve (AUC) and the diagnostic odds ratios (DORs) as measures of diagnostic accuracy.

For IL-6, we included 7 reports for day 1 and 4 reports for days 2 and 3. For IL-8, we analyzed 5 studies for day 1 and 4 for day 2. The pooled IL-6 sensitivities ranged between 81.0 and 83.6% and specificities between 75.6 and 85.3% with positive likelihood ratios of 3.43, 4.90 and 4.40 for days 1, 2 and 3, respectively. The IL-8 pooled sensitivities were 65.8 and 70.9% with specificities of 66.5 and 91.3% for days 1 and 2 with positive likelihood ratios of 1.96 and 8.15. The IL-6 AUCs were 0.75, 0.88 and 0.85 for days 1, 2 and 3. The IL-8 AUCs were 0.73 and 0.91 for days 1 and 2. The DOR for IL-6 was higher than that of IL-8 on day 1.

IL-6 and IL-8 seem to perform at an acceptable level in predicting SAP. Larger confirmatory studies formally comparing this performance with that of more commonly used markers are needed.