ALANINE AMINOTRANSFERASE/ASPARTATE AMINOTRANSFERASE RATIO REVERSAL AND PROLONGED PROTHROMBIN TIME: A SPECIFIC INDICATOR OF HEPATIC CIRRHOSIS
AbstractBackground: Both ALT/AST ratio reversal (AST/ALT>1) and prolonged prothrombin time areseparately related to hepatic cirrhosis. Ratio reversal means that in normal individuals ALT ismore than AST and thus ALT/AST> 1 but with development of cirrhosis AST becomes › ALT andso AST/ALT>1 or ALT/AST<1. This study was conducted with the idea that prolongedprothrombin time and reversed (AST/ALT >1) ratio together can prove a more specific indicatorwith a high positive predictive value for the detection of hepatic cirrhosis in patients of chronicliver disease than either of the two alone. Method: This is a comparative cross sectional study.The data of hepatitis B & C patients was collected from the general medical ward and medical outpatient department. Clinical and Ultrasonographic features, detected by a single ultrasonologist,were used to diagnose cirrhosis. Patients who were alcoholic were excluded from the study asalcohol itself causes ALT/AST ratio reversal. To avoid laboratory errors and variations thefacilities of only a single specific laboratory were used for this study. The sensitivity andspecificity of ALT/AST ratio reversal along with positive predictive value were calculated. Thenprolonged prothrombin time (PT) and reversed ratio together were used and the results of thesetwo groups were compared. Results: It was found that the reversal of ratio alone is 88% specificas an indicator of hepatic cirrhosis and almost 70% sensitive and have a positive predictive valueof 94.5%. The statistical significance test based on z -test for difference of proportion yields:z=6.96 with a p value=0.0000. On the other hand, the prolonged PT and ratio reversal are 98%specific and 53.9% sensitive with a positive predictive value of 98.2%. z -test for difference ofproportion yields here: z=6.23 with a p value=0.0000. Conclusion: ALT/AST ratio reversal alonehas a high sensitivity and the combined effect of these two parameters increases the specificity ascompared to either of the two alone. The high positive predictive value here shows that almost allthe patients with reversed ratio and prolonged PT will have cirrhosis.Key Words : ALT/AST ratio reversal, Prolonged PT, Hepatic Cirrhosis.
Sheth SG, Flamm SL, Gordon FD, Chopra S. AST/ALT ratio
predicts cirrhosis in patients with chronic hepatitis C virus
infection. Am J Gastroenterol 1998; 93(1): 44-8.
Pohl A, Behling C, Oliver D, Kilani M, Monson P, Hassanein
T. Serum aminotransferase levels and platelet counts as
predictors of degree of fibrosis in chronic hepatitis C virus
infection. Am J Gastroenterol 2001; 96(11): 3142-6.
Khokhar N. Serum aminotransferase levels and platelet count
as predictive factor of fibrosis and cirrhosis in patients with
chronic hepatitis C infection. J Pak Med Assoc 2003;
Imperiale TF, Said AT, Cummings OW, Born LJ. Need for
validation of clinical decision aids: use of the AST/ALT ratio
in predicting cirrhosis in chronic hepatitis C. Am J
Park GJ, Lin BP, Ngu MC, Jones DB, Katelaris PH.
Aspartate aminotransferase: alanine aminotransferase ratio in
chronic hepatitis C infection: is it a useful predictor of
cirrhosis? J Gastroenterol Hepatol 2000; 15(4):386-90.
Park JH, Park CK, Kim ES, Park SY, Jo CM, Tak WY et al.
The diagnostic value of serum hyaluronic acid, 7S domain of
type IV collagen and AST/ALT ratio as markers of hepatic
fibrosis in chronic hepatitis B and cirrhosis patients. Taehan
Kan Hakhoe Chi. 2003;9(2):79-88.