Increased ICU Rates Among Children With Trisomy 21 in the Setting of Mycoplasma Infection

Introduction: Mycoplasma pneumoniae is a highly contagious pathogen that commonly causes community-acquired pneumonia. While this is generally a mild disease, a large-scale outbreak in the US in 2024 led to increased hospitalizations and intensive care unit (ICU) admissions among children. We observed that severe illness appeared to disproportionately affect our Trisomy 21 population. We analyzed all patients with a diagnosis of M. pneumoniae infection admitted to our tertiary care children's hospital. The aim of this study was to describe the illness course of children hospitalized with M. pneumoniae in our large urban academic medical center and better characterize Mycoplasma infections in hospitalized children with Trisomy 21.


Methods: A retrospective cohort study was performed to identify all patients with Mycoplasma-related disease admitted to our hospital between November 2023 and February 2025. Patient characteristics including the presence or absence of Trisomy 21, patient age at admission, past medical history, hospital and ICU length of stay, and maximal respiratory support required were analyzed.


Results: We identified 247 admitted children with Mycoplasma-related disease, of which 45 (18.2%) had Trisomy 21. Of the 247 patients, 81 patients required ICU admission, including an ICU admission rate of 55.5% (25/45) in patients with Trisomy 21 and 27.7% in those without Trisomy 21 (p=0.00062). Children with Trisomy 21 tended to have higher respiratory requirements, and longer length of stays (4d vs 2d, p=0.00029). The Trisomy 21 group did not have more pulmonary medical history, and there was no detectable difference in needs for advanced respiratory support.


Conclusions: While there is very little published on the effects of Mycoplasma in the Trisomy 21 population, our study demonstrated that children with Trisomy 21 are more likely to be admitted to the ICU and experience longer hospitalization. While the cause of this is unclear, there are several potential factors including under diagnosed respiratory disease and structural airway issues, as well as possible pulmonary vascular disease in the setting of increased frequency of congenital heart disease. Further research is needed to see if more aggressive management in this population may decrease ICU requirements and length of stay.