biostudies-literatureWei Ythe Project Funding Joint Construction Project of Henan Medical Science and Technology Tackling Plan327https://www.ebi.ac.uk/biostudies/studies/S-EPMC12752153biostudies-literatureUnknown51(1)<h4>Background</h4>Infectious mononucleosis (IM) may lead to severe complications and present diagnostic challenges in certain clinical settings. This study aimed to preliminarily evaluate the clinical utility of novel CBC-derived graphical and numerical indicators as potential tools for rapid, accurate early diagnosis and monitoring of IM in children.<h4>Methods</h4>A total of 204 pediatric patients with IM, exhibiting a favorable prognosis, 109 pediatric patients diagnosed with other infectious diseases, and 86 healthy controls were enrolled from the Third Affiliated Hospital of Zhengzhou University. Multiple complete blood count (CBC)-derived indicators-including the machine learning-based "IM" flag, high-fluorescence lymphocyte percentage (HFLC%), and platelet-to-lymphocyte ratio (PLR)-were analyzed at initial diagnosis and on days 7, 14, and 21.<h4>Results</h4>The "IM" flag, HFLC%, and PLR were independent predictors of IM (all P < 0.01). The "IM" flag and PLR demonstrated high diagnostic efficacy across all pediatric age groups, while HFLC% showed significant diagnostic utility specifically in children over 72 months (all P < 0.001). Optimal diagnostic cutoff values were 1.95 for HFLC% and 46.35 for PLR. During follow-up, the "IM" flag gradually turned negative within 7 days (P < 0.017), HFLC% decreased significantly (all P < 0.01), whereas PLR levels showed a progressively increasing trend over 14 days (all P < 0.001).<h4>Conclusions</h4>The "IM" flag, HFLC%, and PLR demonstrate significant diagnostic and prognostic value in pediatric IM, supporting their potential for clinical application.Italian journal of pediatrics"Infectious mononucleosis" flag, high-fluorescence lymphocyte percentage, and platelet-to-lymphocyte ratio as diagnostic and prognostic biomarkers for infectious mononucleosis in Chinese children.PMC12752153LHGJ20200458Wang PYuan EZhang KWei Yfalse"Infectious mononucleosis" flag, high-fluorescence lymphocyte percentage, and platelet-to-lymphocyte ratio as diagnostic and prognostic biomarkers for infectious mononucleosis in Chinese children.<h4>Background</h4>Infectious mononucleosis (IM) may lead to severe complications and present diagnostic challenges in certain clinical settings. This study aimed to preliminarily evaluate the clinical utility of novel CBC-derived graphical and numerical indicators as potential tools for rapid, accurate early diagnosis and monitoring of IM in children.<h4>Methods</h4>A total of 204 pediatric patients with IM, exhibiting a favorable prognosis, 109 pediatric patients diagnosed with other infectious diseases, and 86 healthy controls were enrolled from the Third Affiliated Hospital of Zhengzhou University. Multiple complete blood count (CBC)-derived indicators-including the machine learning-based "IM" flag, high-fluorescence lymphocyte percentage (HFLC%), and platelet-to-lymphocyte ratio (PLR)-were analyzed at initial diagnosis and on days 7, 14, and 21.<h4>Results</h4>The "IM" flag, HFLC%, and PLR were independent predictors of IM (all P < 0.01). The "IM" flag and PLR demonstrated high diagnostic efficacy across all pediatric age groups, while HFLC% showed significant diagnostic utility specifically in children over 72 months (all P < 0.001). Optimal diagnostic cutoff values were 1.95 for HFLC% and 46.35 for PLR. During follow-up, the "IM" flag gradually turned negative within 7 days (P < 0.017), HFLC% decreased significantly (all P < 0.01), whereas PLR levels showed a progressively increasing trend over 14 days (all P < 0.001).<h4>Conclusions</h4>The "IM" flag, HFLC%, and PLR demonstrate significant diagnostic and prognostic value in pediatric IM, supporting their potential for clinical application.2025-01-01T00:00:00Z2025 Dec2026-06-06T08:30:56.291Z2026-05-27T03:12:32.92ZS-EPMC127521534143062210.1186/s13052-025-02182-6