Low maternal vitamin D is associated with increased risk of congenital and peri/postnatal transmission of Cytomegalovirus in women with HIV

CMV infection of the fetus or neonate can lead to devastating disease, and there are no effective prevention strategies to date. Vitamin D is a potent immunomodulator, supports antiviral immune responses, and plays an important role in placental immunity. Retrospective cohort study to evaluate the impact of low maternal vitamin D on congenital and early postnatal transmission of CMV among HIV-infected, non-breastfeeding women and their HIV exposed but negative infants from an urban HIV clinic. Vitamin D panel was performed on stored maternal plasma obtained near time of delivery. Infant CMV testing at 0-6 months included urine and oral cultures, and/or serum polymerase chain reaction testing. Cohort included 340 mother-infant pairs (births 1991-2014). Among 38 infants (11%) with a CMV+ test between 0-6 months, 4.7% (14/300) had congenital CMV transmission (CMV+ test 0-3 weeks), and 7.6% (24/315) had peri/postnatal CMV (CMV+ test >3 weeks-6 months). Women with lower calcitriol (1,25-dihydroxyvitamin D), the active form of vitamin D, were more likely to have an infant with congenital (OR 12.2 [95% CI 1.61-92.2] P = 0.02) and peri/postnatal (OR 9.84 [95% CI 2.63-36.8] P = 0.0007) infections in multivariate analyses, independent of maternal HIV viral load and CD4 count. This study demonstrates an association between inadequate maternal calcitriol during pregnancy and increased congenital and early postnatal acquisition of CMV among non-breastfeeding women with HIV and their HIV negative infants.