Usefulness of lipase / amylase ratio in acute pancreatitis in South Indian population.

This retrospective study was conducted to assess the serum lipase / amylase ratio in acute pancreatitis for South Indian population attending the clinics of Gastroenterology and Emergency medicine in the last five years. One thousand one hundred and thirty two patients (768 males and 364 females) with acute pancreatitis (AP) were selected for the study. The diagnosis of AP was based on clinical evaluation, Computed Tomography (CT) findings and biochemical parameters such as serum lipase and amylase. Based on the etiology, the groups were divided into alcoholic, biliary and miscellaneous AP. Based on CT findings, groups were divided into mild, moderate and severe AP. Serum lipase, amylase and lipase / amylase ratio were calculated and statistically analyzed. Serum lipase levels in alcoholic group (3226.3 ± 1384.7) were significantly lower in comparison to biliary (6064.5 ± 1640.8) group though the levels were not significantly different from miscellaneous group (2132.3 ± 1210). Serum amylase values were significantly lower in alcoholic group (923.4 ± 557.5) in comparison to biliary (1736.2 ± 390.7) and there was significant difference between alcoholic and miscellaneous group (535.8 ± 477.6). The serum lipase / amylase ratio > 4 occurred in alcoholic group than with biliary and miscellaneous group. The sensitivity and specificity to predict alcoholic AP with lipase / amylase ratio at >4.0 was 84 % and 59 % respectively. In conclusion the serum lipase to amylase ratio greater than 3.0 could be used to differentiate but keeping the cut off at 4.0 would be of higher sensitivity without much change in specificity. The serum lipase to amylase ratio with a cut off of 3.0 or greater is not useful to differentiate the severe AP from milder AP. Hence, serum amylase and lipase are important for evaluation of pancreatitis though it is not a gold standard for the diagnosis or assessment of severity of acute pancreatitis.