What are the appropriate laboratory tests for an infant whose mother has hepatitisC virus (HCV) infection?
What are the appropriate laboratory tests for an infant whose mother has hepatitis C virus (HCV) infection?-- Robert Blereau, MD
Morgantown, LaThe prevalence of antibodies to HCV in pregnant women is around1% (range, 0.1% to 2.4%).1 Of pregnant women in whom HCV antibodiesare detected, 60% to 70% are actively viremic. Vertical transmissionof HCV appears to occur only when serum HCV RNA is detectableand may be more common with higher levels of viremia (above106 copies/mL).1-3When a pregnant woman has detectable HCV RNA at the time of delivery,the risk of transmission is 4% to 7%. Maternal coinfection with HIV increasesthis risk to as high as 20%.4 Although there are no data to support the useof elective cesarean section for the prevention of vertical transmission of HCV,it is prudent to avoid fetal scalp monitoring and prolonged rupture of membranes;either may increase the risk of transmission. The use of interferon orribavirin is contraindicated during pregnancy. Breast-feeding does not appearto transmit HCV but should be avoided if the nipples are cracked or bleeding.5HCV antibodies are transferred through the placenta, and they may bedetected in the infant for as long as 15 months--and occasionally 18 months--after birth.1,6 If transmission of the virus occurs, HCV RNA can be detected afew days after delivery and may persist or be cleared spontaneously. The frequencyand rate of spontaneous clearance are unknown, but infants appear toclear the infection more often than adults.Screen an infant born to an HCV-infected mother for HCV RNA once betweenthe ages of 2 and 6 months and again between 18 and 24 months; at thesecond screening, also test for anti-HCV.1,6 Suspect chronic infection if theselatter tests are positive.
-- Andr N. Sofair, MD, MPH
Assistant Professor of Medicine
Yale University School of Medicine
New Haven, Conn
REFERENCES:
1.
Roberts EA, Yeung L. Maternal-infant transmission of hepatitis C virus infection.
Hepatology.
2002;36:S106-S113.
2.
Dienstag J. Sexual and perinatal transmission of hepatitis
C. Hepatology.
1997;26:S66-S70.
3.
Ohto H, Terasawa S, Sasaki N, et al. Transmission of hepatitis C virus from mothers to infants.
N EnglJ Med.
1994;330:744-750.
4.
National Institutes of Health Consensus Development Conference Statement: management of hepatitis C2002.
Gastroenterology.
2002;123:2082-2099.
5.
Centers for Disease Control and Prevention. Recommendations for prevention and control of hepatitis Cvirus (HCV) infection and HCV-related chronic disease.
MMWR.
1998;47(RR-19):1-39.
6.
Pawlotsky JM. Use and interpretation of virologic tests for hepatitis C.
Hepatology.
2002;36:S65-S73.