Diagnostic and prognostic value of virologic tests in vertical transmission of hepatitis C virus infection: results of a large prospective study in pregnant women.

Background/aims: This study aimed to evaluate the value of virologic tests for the diagnosis and prognosis of hepatitis C virus (HCV) vertical transmission in a large cohort of human immunodeficiency virus (HIV)-seronegative pregnant women.

Methodology: HCV RNA and viral load were tested at the first and third trimester of pregnancy as well as at time of delivery, and from their newborns at birth and after 6, 12, 24, and 36 months. Viral genotype was determined in both viremic mothers and newborns.

Results: Antibodies to HCV were detected in 119 mothers (0.57%), whereas serum HCV RNA tested positive in 67% of them. Interestingly, presence of serum HCV RNA was only observed in 2 babies born to 80 HCV RNA-positive mothers (transmission rate: 2.4%), appearing immediately after birth and remaining positive during the entire follow-up (36 months). These two babies raised serum transaminase levels and had the same HCV genotype (1b) as their respective mothers who had intermediate or low viral load.

Conclusions: Vertical HCV transmission is an infrequent event among HIV-negative HCV-infected mothers, and the presence of serum HCV RNA immediately after birth had a high diagnostic and prognostic value, as identified those newborns who developed chronic hepatitis C.