[Identification of the cutoff value for serum alanine aminotransferase in hepatitis C screening of patients with chronic renal failure on hemodialysis].

The patients with chronic renal failure in hemodialysis present low levels of serum alanine aminotransferases. In order to establish a better cutoff value for ALT in hepatitis C screening of hemodialysis patients, the ALT levels were measured monthly in 235 patients, being excluded those that presented average above the upper limit of normality. The cutoff value was identified by construction of a ROC curve (receiver operating characteristic). Among 202 patients, 15 (7.4%) presented antibodies to hepatitis C virus (anti-HCV) and 187 (92.6%) were anti-HCV negative, with an ALT average of 0.7 and of 0.5 from ULN (p <0.0001), respectively. The better cutoff value for ALT was at 0.6 from ULN, with sensitivity of 67% and specificity of 75% in anti-HCV screening. These results suggest that ULN of ALT could be reduced for 60% from conventional limit, when we are evaluating patients with CRF in hemodialysis.