Mediastinitis secondary to invasive infection by group A Streptococcus in Spain.

This study describes 5 mediastinitis cases secondary to invasive group A Streptococcus (iGAS) disease in a recent outbreak in Spain. Among 398 iGAS cases between January 2019-March 2023, 5 (1.3%) were mediastinitis, 4 occurring in December 2022, all secondary to pneumonia or deep neck infection. We outline the clinical outcome with a review of the scarce pediatric literature.  Conclusion: mediastinistis is a rare but severe complication of iGAS and a high level of suspicion is required to diagnose it. What is Known: • Group A Streptococcus can cause invasive and severe infections in children. • Mediastinitis is a severe complication from some bacterial infections, mainly secondary due to deep-neck abscesses. What is New: • Mediastinitis is an unrecognized complication due to an invasive group A Streptococcus (iGAS) infection. • In cases of a deep-neck abscess or complicated pneumonia a high clinical suspicion of iGAS mediastinitis is required, especially when the clinical course is not favorable.