Clinical Features and Predictors of Hospital Stay in Paediatric Epstein–Barr Virus Infectious Mononucleosis: A Multicentre Cohort Study
Lasse H. Nyhegn, Sara Yde Steffensen, Sabine Frølich Maarbjerg, Luise Borch, Marianne Kragh Thomsen, Mette HolmABSTRACT
Aim
To describe age‐specific clinical features and identify predictors of length of hospital stay in children and adolescents with primary Epstein–Barr virus (EBV) infectious mononucleosis (IM).
Methods
This multicentre retrospective cohort study included all children and adolescents aged 0–17 years with a verified primary EBV infection in the Central Denmark Region between March 2020 and March 2025.
Results
Among 1657 serologically verified primary EBV infections, 307 patients (18.5%) required EBV‐related hospitalisation. Hospitalisation incidence increased with age. Although adolescents accounted for most EBV‐related admissions (77.5%), EBV‐infected children below 7 years were hospitalised more often (one in four) than children aged 7 years or older (one in seven). The most common presenting symptoms were tonsillitis (77%), fever (75%) and lymphadenopathy (64%). Hepatic dysfunction was frequent, particularly among adolescents, whereas anaemia and hyperbilirubinemia occurred more often in younger children. Prolonged length‐of‐stay was independently associated with hyperbilirubinemia, elevated C‐reactive protein, organomegaly and secondary bacterial infection.
Conclusion
Disease severity in paediatric EBV infection was associated with inflammatory and hepatic complications rather than age. Early identification of these features may support risk stratification and optimise inpatient care.