Quantitative RT PCR in the Diagnosis of Congenital Cytomegalovirus Infection with Special Reference to Sensorineural Hearing Loss in a Tertiary Care Centre in North Kerala

Abstract

Background:Cytomegalovirus, a Herpes virus is the most common virus causing congenital viral infections. Sensorineueal hearing loss is the most common non hereditary manifestation. Majority of the babies are asymptomatic or have non specific symptoms at birth. An early diagnosis can help in starting antiviral treatment based on the clinical disease to prevent end organ damage and to intervene early in babies with hearing impairment which can reduce long term sequelae. Objectives :The aim of the study is to diagnose and quantitate neonatal CMV infection by qRTPCR (Quantitative Real Time Polymerase Chain Reaction) ,to evaluate the proportion and clinical profile of congenital CMV infections in a tertiary care hospital. Materials and Methods:This cross sectional diagnostic evaluation was done in the Dept. of Microbiology and Neonatal unit of Dept of Paediatrics, Govt Medical college .Kozhikode from August 2017 to December 2018. Details of demographic data, clinical profile, and CMV viral load in urine in various clinical infections were obtained and analyzed. Urine samples from 225 babies were received and processed in the Microbiology Department. DNA isolation and amplification was performed using commercial DNA extraction kit and CMV PCR kit for detection and quantification of CMV. Results:Of 225 babies with clinical features suggestive of CMV infection, CMV-DNA was detected and quantitated in urine of 27 babies (12%). The most common clinical presentation was hearing impairment, seen in 22 babies. Conclusion:RT-qPCR helps in diagnosing and quantitating CMV in congenital neonatal infection which helps in deciding on therapy and assessing response to treatment and can predict risk for long term sequelae. Diagnosis of congenital CMV in the newborn period is important for identifying those with neurologic abnormalities where appropriate treatment and management is essential.