Clinical features and outcomes of herpes simplex viral infections with co-infection in 100 children.

Objective: To analyze the clinical features, laboratory findings, and treatment outcomes of febrile hospitalized children with herpes simplex virus (HSV) detected by serological and/or molecular biological tests, and to provide an evidence-based basis for the early clinical screening, differential diagnosis and targeted intervention of HSV in pediatric febrile cases. Methods: A retrospective analysis was performed on the clinical data of 100 febrile children with positive HSV test results who were admitted to Jinan Children's Hospital from January 2018 to October 2024. The collected data included demographic characteristics, clinical manifestations, confirmed clinical diagnoses, co-detected pathogen status(diagnosed by a combination of serology, PCR and microbial culture), laboratory examination indicators, treatment regimens(including individualized acyclovir course), and prognostic outcomes. HSV detection was conducted by serum HSV-IgM antibody assay and/or HSV-DNA detection in pharyngeal swab/blood samples, and the number of cases with single positive and double positive results of the two tests was statistically analyzed separately. All statistical analyses were performed using SPSS 26.0 software, with measurement data described as median [interquartile range (IQR)] and compared by Mann-Whitney U test. A two-sided Results: Among the 100 children, 62 were male and 38 were female, with a male-to-female ratio of 1.6:1. The age ranged from 1 month to 8 years, with a median age of 2.1 years, and the 1 to <3 years age group accounted for the highest proportion (56.0%, 56/100). Fever was the primary admission symptom in all cases, with 72.0% (72/100) presenting with high fever (≥39 °C). The most common local manifestation was oral mucosal lesions (19.0%, 19/100). Physical examination showed cervical lymphadenopathy in 85.0% (85/100) and pharyngeal mucosal congestion/redness in 92.0% (92/100) of the children. Of the 100 HSV-positive cases, 65 (65.0%) were double positive for HSV-IgM and HSV-DNA, 23 (23.0%) were single positive for HSV-IgM, and 12 (12.0%) were single positive for HSV-DNA. Other pathogens were co-detected in 52.0% (52/100) of the cases, with Epstein-Barr virus (EBV) being the most common (27.0%, 27/100). Abnormal liver function (elevated alanine aminotransferase [ALT] and/or aspartate aminotransferase [AST]) was found in 30.0% (30/100) of the children. Ninety-two children received intravenous acyclovir for antiviral treatment, with a median time to defervescence of 2.5 days (IQR: 2.0-3.0) and a median hospital stay of 7.0 days (IQR: 6.0-8.0). All children were cured and discharged. Statistical analysis showed that children who received early acyclovir treatment (within 24 h of admission) had significantly shorter time to defervescence and hospital stay compared with those in the delayed treatment group (>24 h) (Z = -3.874 and -4.125, respectively, both Conclusion: HSV is a frequently isolated pathogen in febrile infants and young children with herpetic gingivostomatitis as the core clinical diagnosis and diverse clinical manifestations dominated by non-specific systemic and oropharyngeal symptoms (cutaneous herpes with low incidence). HSV infection is often accompanied by co-detection of other pathogens such as EBV and Bordetella pertussis (diagnosed by standardized serological, PCR and microbial culture methods) and abnormal liver function in some cases. Early HSV-PCR detection combined with serological testing, timely and individualized acyclovir treatment (with clear course standards) based on comprehensive clinical judgment can significantly improve the clinical outcomes of febrile children with HSV detected. Comprehensive intervention targeting co-detected pathogens and complications is equally important for the clinical management of such cases.