INCIDENCE OF HEPATITIS-C VIRUS-INFECTION IN ITALIAN PATIENTS WITH IDIOPATHIC PULMONARY FIBROSIS

Background - A viral cause of idiopathic pulmonary fibrosis (IPF) was recently suggested by a Japanese study in which a high prevalence of a nti-hepatitis C virus (HCV) antibodies was detected. A subsequent Brit ish study failed to confirm these results. Methods - Antibodies to HCV were evaluated in 60 patients with IPF, 130 patients with non-interst itial lung disease, and in 4614 blood donors. HCV-RNA and HCV genotype s were evaluated in the anti-HCV positive patients with IPF. Anti-HCV antibodies were evaluated by ELISA and confirmed by recombinant immuno blotting assay (RIBA). HCV-RNA and genotypes were detected by reverse transcriptase polymerase chain reaction (PCR). Results - Eight patient s with IPF had anti-HCV antibodies detected by ELISA (13.3%). In the b lood donor control group the prevalence of HCV antibodies was lower (0 .3%). In patients with non-interstitial lung disease HCV antibody prev alence was 6.1%. In all eight patients with IPF found to be anti-HCV p ositive by ELISA, HCV antibodies were also detected by RIBA. Furthermo re, all were HCV-RNA positive by PCR assay. HCV genotypes were identif ied in four of these eight patients. In all four genotype II was prese nt and in two it was associated with genotype III and/or genotype IV. In the remaining four cases the genotype was not identified. Conclusio n - Italian patients with IPF show an increased prevalence (similar to 13%) of HCV infection and viral replication, but the prevalence of an ti-HCV antibodies does not differ from other lung diseases.