Medline ® Abstract for Reference 19

BACKGROUND: The AST to platelet ratio index (APRI), a non-invasive marker of liver fibrosis, has not been well studied in HCV/HIV (hepatitis C virus/human immunodeficiency virus) co-infected patients with advanced HIV.

AIM: To compare the accuracy of APRI in HCV/HIV co-infected patients to that in HCV mono-infected patients and to determine the impact of CD4+ T-cell counts on its performance.

METHODS: We identified 106 consecutive HCV/HIV co-infected patients and 105 matched HCV mono-infected patients who underwent liver biopsy at Harborview Medical Center over a 5-year period. Performance characteristics were calculated and receiver operating characteristic (ROC) analysis conducted.

RESULTS: The area under the ROC curve (AUROC) of APRI for predicting significant fibrosis was similar when comparing those with and without HIV co-infection (0.77 vs. 0.86, P = 0.18), but was lower in HIV co-infected patients with CD4 counts<250 cells/mm³(0.64 vs. 0.86, P = 0.05). In HIV co-infected patients with CD4 counts≥250, APRI had higher negative predictive value (93% vs. 88%, P = 0.57), positive predictive value (63% vs. 40%, P = 0.43) and specificity (95% vs. 88%, P = 0.05) than in those with lower CD4 counts.

CONCLUSIONS: The AST to platelet ratio index (APRI) performance characteristics appear to be suboptimal in HCV/HIV co-infected patients with CD4 counts<250 and they require further study in this population at increased risk for advanced liver disease.