Pyomyositis in Children: A 15-Year Retrospective Study

Strategic Insights -

Researchers at the Hospital de Dona Estefania in Lisbon, Portugal, have conducted a comprehensive study on pyomyositis, a primary infection of the skeletal muscle, commonly occurring in tropical countries in children. The study, published in the Pediatric Infectious Disease Journal, aimed to investigate the clinical, laboratory, and radiological findings of pyomyositis in children, as well as the most common treatment options and outcomes.

Key Takeaways:

  • The study identified 29 patients with pyomyositis, with 75.9% being male and a median age of 8 years old.
  • The most common predisposing factors for pyomyositis were intense physical activity (37.9%) and trauma (31.0%).
  • Pain (100.0%), functional impairment (82.8%), and fever (65.5%) were the most frequent symptoms.
  • The most affected sites were the pelvis (51.6%) and the upper leg (22.6%).
  • Magnetic resonance imaging had 100% sensitivity, while ultrasounds were inconclusive in 40.7% of cases.
  • Methicillin-sensitive Staphylococcus aureus was the most common isolated organism (36.0%).
  • Most patients were treated with intravenous flucloxacillin plus clindamycin (55.2%) for a median of 14 days and a median total duration of 29 days.
  • Drainage was only performed in 20.7% of patients, with 6/15 patients in the suppurative phase.
  • All patients improved without functional impairment at 6-month follow-up.

Statistics:

  • 75.9% of patients with pyomyositis were male.
  • 51.6% of patients had the most affected sites as the pelvis.
  • Intense physical activity was the most common predisposing factor (37.9%).
  • 100.0% of patients had pain as a symptom.
  • 40.7% of ultrasounds were inconclusive.
  • 36.0% of patients had Methicillin-sensitive Staphylococcus aureus as the isolated organism.
  • 55.2% of patients were treated with intravenous flucloxacillin plus clindamycin.
  • 20.7% of patients required drainage, with 6/15 patients in the suppurative phase.

Sources:

  • Pyomyositis In Children: a 15-year Retrospective Study From a Tertiary Care Pediatric Hospital In Portugal. Pediatric Infectious Disease Journal, 2025;44(10).
  • Hospital de Dona Estefania, Ulss Jose, Dept. of Pediatrics, Rua Jacinta Marto 8A, Lisbon, Portugal.
  • Lippincott Williams & Wilkins, Two Commerce Sq, 2001 Market St, Philadelphia, PA 19103, USA.
  • Pediatrics Week. October 25, 2025; p 137.