Epidemiology and natural history of hepatitis C virus infection

Table 3 Serum levels of hepatitis C virus RNA and liver-related diseases

Ref.	Study population	Study design	Serum RNA measurements	Findings	Comments
Naito et al[50]	22 HCV carriers with detectable RNA and persistently normal serum ALT levels in Japan	Cross-sectional	Competitive RT-PCR	Serum viral load were correlated with HAI score (r = 0.68, P < 0.01)	Limited number of study participants
					Temporality
					No control for confounders
De Moliner et al[45]	96 patients without antiviral treatments in Italy	Cross-sectional	First-generation bDNA assay (QuantiplexTM HCV RNA 1.0)	Serum viral load was not correlated with liver histological diagnosis (r = 0.58)	Temporality
					No control for confounders
Fanning et al[47]	77 women infected HCV genotype 1b through vaccination in Ireland	Cross-sectional	RT-PCR	Serum viral load was weakly (r = 0.26, P < 0.05) correlated with HAI score	Temporality
				Not correlated with the degree of fibrosis (r = 0.22, P > 0.05)	Homogeneous participants with defined source of infection and the same duration of infection
Lagging et al[48]	98 patients without antiviral treatments in Sweden	Cross-sectional	RT-PCR with Cobas Amplicor HCV monitor test	Serum viral load was not associated with the degree of inflammation or fibrosis	Temporality
Hisada et al[51]	385 drug users with detectable HCV RNA in United States	Case-cohort	Third-generation of bDNA assay (QuantiplexTM HCV RNA 3.0)	Elevated serum levels of HCV RNA increased the risk of ESLD death (relative hazard = 2.3 per log10 IU/mL, 95%CI: 1.5-5.9)	Coinfected with HIV or HTLV-II
					Large population with eight yr of follow-up

RT-PCR: Reverse-transcription polymerase chain reaction; HAI: Histological activity index; HCV: Hepatitis C virus; ESLD: End-stage liver disease; HTLV: Human T lymphotropic virus; HIV: Human immunodeficiency virus.