Epidemiology and Characterization of Immunological Disorders in Children Diagnosed With Pneumococcal Invasive Disease.

Aim: A substantial proportion of children hospitalized with invasive pneumococcal infection are subjected to immune evaluations, to detect immunological disorders (ID). The literature lacks thorough analysis of the necessity and effectiveness of these evaluations for previously healthy children with such infections. We aimed to examine the occurrence and characteristics of ID in children hospitalized with invasive pneumococcal disease (IPD), and to assess when immune investigations are most effective. Methods: In a retrospective study, we examined the immunological assessments and outcomes of children with IPD admitted during 2010-2023 to Schneider Children's Medical Center. Results: Out of 219 children with IPD, 144 previously healthy patients were included, with a mean age of 2.2 years and an average hospital stay of 9 days. Immunological evaluations, defined as any immune-related assessment, were performed in 94 patients (65.3%) and were not uniform across the cohort. ID were identified in 15 of 144 children (10.4%), corresponding to 15 of 94 evaluated patients (15.9%). Functional hyposplenism was the most frequent finding. No clinical or laboratory features reliably distinguished those with ID. Conclusion: Immunological evaluation should be considered in previously healthy children diagnosed with IPD. Functional hyposplenism should be considered when routine immunological evaluation is unrevealing; however, the role of universal spleen scintigraphy requires further prospective evaluation.