The clinical significance of hyperamylasemia in organophosphate poisoning

Objective: Hyperamylasemia with a presumptive diagnosis of acute pancreatit is has been reported following organophosphate poisoning but there are no l arge-scale studies incorporating more specific diagnostic criteria. Methods : Retrospective review of the medical records of 159 patients with a diagno sis of organophosphate poisoning over 3 years. Serum amylase, pancreatic am ylase, salivary amylase, lipase and cholinesterase levels, and the clinical manifestations were analyzed. Results: Serum amylase data was available fo r 121 of the 159 study patients. Hyperamylasemia (amylase greater than or e qual to 360 U/L) was found in 44 patients (36%). Lipase was measured in 28 patients with hyperamylasemia; 9 of 28 had hyperlipasemia (lipase greater t han or equal to 380 U/L). The finding of hyperamylasemia was closely relate d to clinical severity and presence of shock. A presumptive diagnosis of pa inless acute pancreatitis was diagnosed by hyperlipasemia associated with h yperamylasemia, clinical severity, serum LDH, and leukocyte counts. Two pat ients with presumptive pancreatitis died. Shock, coma, and hypoalbuminemia were the factors predicting fatality. Conclusions: Hyperamylasemia is frequ ent in severe organophosphate poisoning. However, hyperamylasemia is not sy nonymous with acute pancreatitis and pancreatic amylase is not a reliable p arameter in the diagnosis of organophosphate-induced pancreatitis due to it s low sensitivity and specificity. Lipase assay is indicated in patients wi th hyperamylasemia for early diagnosis of pancreatitis. Proper image studie s and even pathological examination are also needed to confirm the extent o f pancreatic injury. With prompt diagnosis and appropriate treatment, a com plete recovery can be anticipated unless the patient has otherwise unrelate d complications.