829. Identification of Congenital Cytomegalovirus Infection Using Real-World Healthcare Data

BACKGROUND: Infants with congenital cytomegalovirus infection (cCMVi) may present with symptoms such as sensorineural hearing loss (SNHL) during the neonatal period and/or develop permanent disability. This study aims to identify infants with cCMVi using information available in an electronic healthcare database in Israel. METHODS: We performed a retrospective study in Maccabi Healthcare Services (MHS, 2.4-million-member healthcare system) among infants with ≥30 days’ continuous enrolment since birth and linked maternal data of women aged 18-44 years in 2013-2017. Data were obtained on diagnosis codes (‘Dx’; ICD-9-CM) of CMV and SNHL and dispensed valgancivlovir treatment (‘Tx’) within 90 days after birth. To help inform the timing of the CMV infection (congenital vs. postnatal) data on maternal CMV testing history were also obtained among infants whose earliest CMV Dx was at age 22-90 days. RESULTS: The study included 171,952 infants linked to 128,264 mothers (167,879 pregnancies). A total of 461 infants (0.3%) had a CMV Dx within 90 days, 81.3% of which (n=375) were diagnosed within 21 days. Among all infants with a CMV Dx within 90 days, 105 also had dispensed Tx (n=101) and/or SNHL Dx (n=16). Among infants diagnosed at age 22-90 days without evidence of prior Tx or SNHL (n=69), 12 had a record of primary maternal CMV infection in pregnancy, 8 had mothers who were CMV seronegative at the start of pregnancy without follow-up test results, and 49 did not have any maternal laboratory data available. A medical record review is being conducted to validate each cCMV case definition in the MHS database. CONCLUSION: In large Israeli healthcare system, 0.3% of infants had a CMV Dx in their electronic health records suggestive of potential cCMVi. Case review is ongoing to validate these codes and help inform analyses on the clinical and economic burden of cCMVi in this population where awareness of CMV is high but newborn screening is not universal. DISCLOSURES: Morgan Marks, PhD, ScM, Merck and Co. Inc. (Employee, Shareholder) Wei Wang, PhD, Merck (Employee) Anushua Sinha, MD, MPH, Merck & Co. (Employee)Merck & Co. (Shareholder)Merck & Co. (Consultant)