A pediatric case of pyomyositis presenting with septic pulmonary emboli

Pyomyositis is a suppurative infection of skeletal muscle most commonly caused by Staphylococcus aureus. It is mainly encountered in children and immunocompromised. Eight year old previously healthy girl presented with confusion, fever and swelling of the right knee two days after a trauma. Abdominal ultrasonography and computerized tomography taken upon development of hematemesis revealed no pathology in the abdomen, but potential bleeding sites in lung sections. Thorax CT images were interpreted in favor of septic pulmonary emboli due to the presence of peripheral nodular consolidation areas with central cavitation, mostly pathchy in medial areas. S. aureus was isolated in the blood culture. At the end of third week of hospitalization, gadolinium enhanced contrast MRI of right extremity was taken to evaluate right extremity swelling and revealed abcess formation as expected in the clinical progress of pyomyositis. Pyomyositis and septic pulmonary emboli are a rare association. This case demonstrates that the high index of suspicion in pediatric cases with muscle findings and septic pulmonary findings and early institution of therapy may improve the prognosis.