Spontaneous viral load decline and subsequent clearance of chronic hepatitis c virus in postpartum women correlates with favorable interleukin-28B gene allele

Abstract

Background. Postpartum hepatitis C viral (HCV) load decline followed by spontaneous clearance has been previously described. Herein we identify predictors for viral decline in a cohort of HCV-infected postpartum women. Methods. Pregnant women at Cairo University were screened for anti-HCV antibodies and HCV RNA, and viremic women were tested for quantitative HCV RNA at 3, 6, 9, and 12 months postpartum. Spontaneous clearance was defined as undetectable viremia twice at least 6-months apart. Associations between viral load and demographic, obstetrical, HCV risk factors, and interleukin- 28B gene (IL28B) polymorphism (rs12979860) were assessed. Results. Of 2514 women, 97 (3.9%) had anti-HCV antibodies, 54 (2.1%) were viremic and of those, 52 (2.1%) agreed to IL28B testing. From pregnancy until 12 months postpartum, IL28B-CC allele women had a significant viral decline (P = .009). After adjusting, the IL28B-CC allele had a near significant difference compared to the CT allele (odds ratio [OR], 0.75; 95% confidence interval [CI], 0.75,1.00; P = .05), but not the TT allele (OR, 0.91; 95% CI, 0.61,1.38; P = .64). All 14/52 (26.9%) women who subsequently cleared were among the 15 with undetectable viremia at 12 months, making that time point a strong predictor of subsequent clearance (sensitivity = 100%, specificity = 97.4%, positive predictive value = 93.3%, negative predictive value = 100%). Conclusions. In this HCV-infected cohort of postpartum women 26.9% spontaneously cleared. IL28B-CC genotype and 12-month postpartum undetectable viremia were the best predictors for viral decline and subsequent clearance. These 2 predictors should influence clinical decision making.