Optimized cutoffs improve performance of the aspartate aminotransferase to platelet ratio index for predicting significant liver fibrosis in human immunodeficiency virus/hepatitis C virus co-infection

Division of Gastroenterology-Hepatitis Section, Federal University of Sao Paulo, Sao Paulo, Brazil.
Liver international: official journal of the International Association for the Study of the Liver (Impact Factor: 4.41). 04/2008; 28(4):486-93. DOI: 10.1111/j.1478-3231.2008.01675.x
Source: PubMed

ABSTRACT To assess the diagnostic value of modified cutoffs for aspartate aminotransferase to platelet ratio index (APRI) to predict significant liver fibrosis in human immunodeficiency virus (HIV)/hepatitis C virus (HCV) patients.
This retrospective cross-sectional study included consecutive patients with HIV/HCV co-infection who underwent percutaneous liver biopsy. The accuracy of APRI for the diagnosis of significant fibrosis (F2/F3/F4 METAVIR) was evaluated by estimating the positive and negative predictive values (PPV and NPV respectively) and by measuring the area under the receiver operating characteristics curve (AUROC).
One hundred and eleven patients were included (73% men, mean age 40.2+/-7.8 years). Significant fibrosis was observed in 45 patients (41%). To discriminate these subjects, the AUROC of APRI was 0.774+/-0.045. An APRI > or = 1.8 showed a PPV of 75% for the presence of significant fibrosis, and an index < 0.6 excluded significant fibrosis with an NPV of 87%. If biopsy indication was based only on APRI and restricted to scores in the intermediate range (> or = 0.6 and < 1.8), 46% of liver biopsies could have been avoided as compared with 40% using the classical cutoffs.
APRI with adjusted cutoffs can predict significant liver fibrosis in patients with HIV/HCV co-infection and might obviate the need to perform a biopsy in a considerable percentage of those subjects.

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