Detection of Cytomegalovirus in Patients Attending a Tertiary Care Center: A Retrospective Analysis

TL;DR

This study found that 26.5% of patients at a hospital in India had active CMV infections, with higher rates in immunocompromised individuals and preterm births.

Contribution

The study provides new prevalence data and clinical insights on active CMV infections in a tertiary care setting using qPCR.

Findings

CMV DNA was detected in 26.5% of 162 patients tested.

Immunocompromised individuals showed a significant association with CMV positivity.

Gastrointestinal symptoms were the most common presenting feature in CMV-positive patients.

Abstract

Introduction

Human cytomegalovirus (CMV) is a DNA β-herpesvirus that establishes lifelong latency in bone marrow-derived CD34+ progenitors and CD14+ monocytes following primary infection. The virus restricts gene expression to prevent replication but reactivates when these cells differentiate into macrophages or dendritic cells, often triggered by inflammation or immunosuppression, and causes significant morbidity. Congenital CMV remains a major global health issue and the leading cause of non-genetic neurodevelopmental impairment worldwide. Compared to seroprevalence studies, fewer studies have evaluated active CMV infection using molecular methods. Quantitative real-time polymerase chain reaction (qPCR)-based detection of CMV DNA provides a reliable measurement of active infection and viral burden.

Objectives

This study was conducted to assess the prevalence, demographic characteristics, and viral load distribution of CMV and to evaluate its clinical spectrum and association with underlying diseases in patients with suspected infection.

Materials and methods

This retrospective analysis was conducted at a tertiary care hospital in Chennai, India, involving 162 patients who were tested from January 2024 to June 2024. Viral DNA was extracted using spin-column extraction kits (Qiagen Blood Mini-kits). CMV DNA detection and quantification were performed using a TaqMan-based real-time PCR assay (Thermo Fisher Scientific, Waltham, MA, USA), targeting the CMV ppUL83 gene on a Rotor-Gene-Q instrument (Qiagen, Hilden, Germany). The lower limit of detection was 50 copies/mL.

Results

In our study, CMV DNA was detected in 43 (26.5%) of the 162 patients. Among the CMV-positive patients, age and gender showed no significant association. Preterm birth was noted in 12 (27.9%) patients. Immunocompromised individuals showed a significant association with CMV positivity; among these, seven (16.3%) patients were transplant recipients, and five (11.6%) patients had hematological malignancies. Gastrointestinal manifestations were the most common presenting feature, seen in 22 (51.1%) patients. Of the 43 CMV-positive individuals, 23 (53.5%) had viral loads ranging from 50 to 10,000 viral DNA copies/mL.

Conclusion

CMV infection represents a significant health burden in tertiary care settings. This study highlights the role of qPCR in the early detection of active CMV infections. Early diagnosis allows timely initiation of antiviral therapy and thereby improves clinical outcomes, particularly in immunocompromised individuals.