Blood Viral Load in Symptomatic Congenital Cytomegalovirus Infection

Background. Viral loads (VLs) frequently are followed during treatment of symptomatic congenital cytomegalovirus disease, but their predictive value is unclear. Methods.Post hoc analysis of 2 antiviral studies was performed. Seventy-three subjects were treated for 6 weeks and 47 subjects were treated for 6 months. Whole blood VL was determined by real-time polymerase chain reaction before and during therapy.Results.Higher baseline VL was associated with central nervous system involvement (3.82 log, range 1–5.65 vs 3.32 log, range 1–5.36; P = .001), thrombocytopenia (3.68 log, range 1–5.65 vs 3.43 log, range 1–5.36; P = .03), and transaminitis at presentation (3.73 log, range 1–5.60 vs 3.39 log, range 1–5.65; P = .009), but with overlap in the amount of virus detected between groups. In subjects treated for 6 months, lower VL at presentation correlated with better hearing outcomes at 12 months, but VL breakpoints predictive of hearing loss were not identified. Sustained viral suppression during 6 months of therapy correlated with better hearing outcomes at 6, 12, and 24 months (P = .01, P = .0007, P = .04), but a majority without viral suppression still had improved hearing.Conclusions.In infants with symptomatic congenital cytomegalovirus disease, higher whole blood VL before initiation of anti-viral therapy has no clinically meaningful predictive value for long-term outcomes.Keywords. antiviral therapy; congenital CMV infection; hearing loss; viral load