The diagnosis of gangrenous acute cholecystitis represents a diagnostic challenge for the physician and is rarely identified preoperatively. We report a longitudinal prospective study in 180 patients who underwent cholecystectomy for acute cholecystitis. A ROC curve was obtained to determine the preoperative cut-off for various biomarkers (neutrophil to lymphocyte ratio [NLR], C-reactive protein [CRP], platelet to lymphocyte ratio [PLR], lactate and procalcitonin) and their association with both preoperative and postoperative findings. The area under the curve (AUC) for NLR, CRP, PLR, lactate and procalcitonin was 0.75, 0.8, 0.65 and 0.6, respectively. NLR > 5 and CRP > 100 are still independent factors for gangrene (adjusted odds ratio [OR], 2 and 2.1, respectively).