The role of polymerase chain reaction in the laboratory diagnosis of infectious mononucleosis in children

Infectious mononucleosis (IM), caused by the Epstein-Barr virus (EBV), remains one of the most pressing problems in pediatric infectology. Despite a relatively favorable course in immunocompetent children, this infection requires accurate laboratory verification for differential diagnosis from acute leukemia, streptococcal sore throat, and other diseases. This review critically analyzes current methods for laboratory diagnostics of IM, with a particular emphasis on polymerase chain reaction (PCR) in its various modifications. The principles of molecular diagnostics, optimal assay matrices, interpretation of quantitative viral load indicators, and age-related characteristics of this method’s use in pediatric practice are discussed. Data on the comparative effectiveness of PCR, serological tests, and direct virus detection methods are presented. Promising approaches, including digital PCR and next-generation sequencing (NGS), in the diagnosis of EBV-associated diseases are discussed. The results of a retrospective analysis of 309 suspected IM cases in children are presented, demonstrating the high diagnostic value of the PCR method. The review is based on an analysis of current international guidelines and meta-analyses of recent years.

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