A NATIONAL French study has reported high intensive care unit (ICU) admission rates and atypical imaging findings in hospitalised adults during a recent Mycoplasma pneumoniae epidemic.
Following a surge in M. pneumoniae cases beginning in September 2023, the MYCADO study aimed to characterise severe outcomes and risk factors among adults hospitalised across 76 centres in France. This retrospective observational study analysed clinical and radiological features of 1,309 patients hospitalised for at least 24 hours between September 2023–February 2024. Researchers used multivariable logistic regression to identify predictors of ICU admission or in-hospital death, the study’s primary composite outcome.
The median patient age was 43 years; 22% had chronic respiratory failure, and 32.3% had cardiovascular comorbidities. Symptoms were typical for respiratory infections, but extra-respiratory manifestations such as autoimmune haemolytic anaemia (3.4%), myocarditis (1.3%), and meningoencephalitis (1.5%) were also observed. Median hospital stay was 8 days. Of the 1,309 patients, 424 (32.4%) had severe outcomes, mostly ICU admissions (31.7%) and 28 deaths (2.1%). Risk factors for severe disease included hypertension, obesity, chronic liver failure, extra-respiratory complications, and bilateral or alveolar consolidation on imaging. Importantly, patients who had not received antibiotics active against M. pneumoniae prior to admission were more likely to deteriorate.
The findings stress the importance of early antibiotic reassessment and considering macrolides as first-line treatment during epidemics. No radiographic pattern should be considered definitively diagnostic or reassuring.
Reference
Gavaud A et al. Mycoplasma pneumoniae infection in adult inpatients during the 2023–24 outbreak in France (MYCADO): a national, retrospective, observational study. Lancet Infect Dis. 2025; DOI: 10.1016/S1473-3099(24)00805-3
