Acute kidney injury after valacyclovir administration for prevention of congenital cytomegalovirus infection

The effect of valacyclovir on secondary prevention of congenital cytomegalovirus infection, following primary maternal infection acquired periconceptionally or in the first trimester of pregnancy. An individual patient data meta-analysis

OBJECTIVE

Recent studies have shown that a dosage of 8 g/d of oral valacyclovir reduces substantially the vertical transmission rate of cytomegalovirus in women with primary cytomegalovirus infection acquired periconceptionally or during the first trimester of pregnancy. This individual patient data meta-analysis aimed to assess the effectiveness and safety of valacyclovir treatment in the secondary prevention of congenital cytomegalovirus infection.

DATA SOURCES

MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, the US registry of clinical trials (www.

CLINICALTRIALS

gov), and gray literature sources were searched from inception to March 2023.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials and quasi-randomized studies administering 8 g/d of oral valacyclovir in pregnant women with primary cytomegalovirus infection acquired periconceptionally or during the first trimester of pregnancy were included.

METHODS

All corresponding authors of the eligible studies were contacted. Cochrane's Risk of Bias 2 and Risk Of Bias In Non-randomised Studies - of Interventions tools were used for the risk of bias assessment. The result of amniocentesis was the primary outcome of interest. A 1-stage individual patient data meta-analysis was performed, using a generalized linear mixed model, clustered by the different trials. A subgroup analysis was performed, assessing separately the effect of valacyclovir in the periconceptional period and first trimester of pregnancy.

RESULTS

Overall, 3 studies were included in the analysis (n=527 women). Valacyclovir reduced the vertical transmission rate of cytomegalovirus (adjusted odds ratio, 0.34; 95% confidence interval, 0.18-0.61). This reduction was apparent for both periconceptional period (adjusted odds ratio, 0.34; 95% confidence interval, 0.12-0.96) and first-trimester (adjusted odds ratio, 0.35; 95% confidence interval, 0.16-0.76) infections. Moreover, valacyclovir reduced the rate of neonatal infection (adjusted odds ratio, 0.30; 95% confidence interval, 0.19-0.47), in both periconceptional period (adjusted odds ratio, 0.30; 95% confidence interval, 0.14-0.61) and first-trimester (adjusted odds ratio, 0.30; 95% confidence interval, 0.17-0.54) infections. Furthermore, valacyclovir reduced the rate of termination of pregnancy because of cytomegalovirus-associated severe fetal findings (adjusted odds ratio, 0.23; 95% confidence interval, 0.22-0.24). The gestational age at the initiation of treatment has a positive correlation with all outcomes. The overall prevalence of severe side effects was 2.1%.

CONCLUSION

A dosage of 8 g/d of oral valacyclovir reduced the vertical transmission rates of cytomegalovirus following primary maternal infection acquired periconceptionally or in the first trimester of pregnancy, with a low incidence of side effects.

New data on efficacy of valacyclovir in secondary prevention of maternal-fetal transmission of cytomegalovirus

OBJECTIVE

Congenital cytomegalovirus (CMV) infection is the leading cause of non-genetic hearing and neurological deficits. The aim of our study was to evaluate the efficacy and safety of valacyclovir (VCV) treatment in preventing CMV transmission to the fetus after maternal primary infection.

METHODS

This was a retrospective, multicenter study evaluating the rate of maternal-fetal CMV transmission in pregnancies with maternal primary CMV infection treated with VCV at a dosage of 8 g per day (VCV group) compared with a control group of untreated women. Each case underwent virological testing to confirm maternal primary infection and to provide accurate dating of onset of infection. The primary outcome was the presence of congenital CMV infection at birth diagnosed based on polymerase chain reaction analysis of saliva, urine and/or blood samples. The efficacy of VCV treatment was assessed using logistic regression analysis adjusted for a propensity score.

RESULTS

In total, 143 patients were included in the final analysis, of whom 59 were in the VCV group and 84 were in the untreated control group. On propensity-score-adjusted analysis, VCV treatment was significantly associated with an overall reduction in the rate of maternal-fetal CMV transmission (odds ratio, 0.40 (95% CI, 0.18-0.90); P = 0.029). The rate of maternal-fetal CMV transmission, determined at birth, in the VCV vs control group was 7% (1/14) vs 10% (1/10) after periconceptional maternal primary infection (P = 1.00), 22% (8/36) vs 41% (19/46) after first-trimester maternal primary infection (P = 0.068) and 25% (2/8) vs 52% (14/27) after second-trimester maternal primary infection (P = 0.244). When analyzing the efficacy of VCV treatment according to maternal viremia at treatment initiation, there was a trend towards greater efficacy when patients were viremia-positive (21% vs 43%; P = 0.072) compared with when they were viremia-negative (22% vs 17%; P = 0.659). Maternal side effects associated with VCV were mild and non-specific in most cases.

CONCLUSION

Our findings indicate that VCV treatment of pregnant women with primary CMV infection reduces the risk of maternal-fetal transmission of CMV and may be effective in cases with primary infection in the first and second trimesters. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.