Elena Chiappini, Marco Renni, Maia De Luca, Samantha Bosis, Silvia Garazzino, Laura Dotta, Raffaele Badolato, Federica Zallocco, Daniele Zama, Antonella Frassanitto, Ilaria Liguoro, Danilo Buonsenso, Claudia Colomba, Lorenza Romani, Giulia Lorenzetti, Federica Ceroni, Marco Denina, Nicolò Monti, Catiuscia Lisi, Luisa Galli, Giangiacomo Nicolini, Guido Castelli Gattinara, Andrea Lo Vecchio, Italian Society of Pediatric Infectious Diseases (SITIP)
BACKGROUND: Group A Streptococcus causes pediatric infections from mild to severe forms. Since late 2022, invasive cases have increased in Europe, possibly due to reduced post-COVID-19 immunity, more respiratory virus circulation, and emergence of virulent strains. METHODS: A retrospective, multicenter observational study was conducted in twelve Italian pediatric Hospitals, including patients under 18 years hospitalized with invasive or severe Group A Streptococcus infection. Data were anonymized and analyzed to identify factors associated with Pediatric Intensive Care Unit (PICU) admission and discharge with sequelae or death. RESULTS: Seventy-five children with invasive or severe Group A Streptococcus infection were included; the majority (69.3%) were aged 2-10 years. Invasive Group A Streptococcus (iGAS) infection accounted for 58.7% (n = 44) and severe GAS (sGAS) infection for 41.3% (n = 31) of cases. Pediatric Intensive Care Unit admission was required in 45.3% (n = 34) of the entire patient cohort, in this subgroup viral coinfection (OR 5.684, p = 0.003), sepsis/septic shock (OR 4.406, p = 0.003), iGAS diagnosis (OR 4.153, p = 0.005), and procalcitonin (PCT) > 0.5 ng/mL (OR 7.105, p = 0.019) were independently associated with admission; the use of corticosteroids (OR 4.641, p = 0.003) and intravenous immunoglobulin (IVIG) (OR 16.667, p = 0.003) was also significantly more frequent. All patients received empirical β-lactam antibiotics; anti-toxin therapy was administered in 47 patients (62.7%): clindamycin (49.3%), linezolid (16.0%), and rifampicin (1.3%). Mechanical ventilation was required in 24.0% (n = 18), and 49.3% (n = 37) underwent surgery. Post-infectious sequelae occurred in 20.0% (n = 15) and four children died, mostly due to streptococcal toxic shock syndrome. CONCLUSION: Pediatric invasive group A streptococcal infection continues to pose a significant clinical challenge, with notable rates of morbidity and mortality, underscoring the need for early recognition and close monitoring of high-risk patients. A widespread use of adjunctive therapies was documented. Continued surveillance and robust clinical research are essential to optimize management strategies and improve patient outcomes.