1 – Pediatric Infecciology department, Hospital. Dona Estefânia, CHLC- EPE Lisbon, Portugal
2 – Pediatric Orthopedics department, Hospital Dona Estefânia, CHLC- EPE Lisbon, Portugal
- 7th Europaediatrics Congress of the European Paediatric Association (EPA), Florença, 13-16 de Maio de 2015 (poster).
Introduction: For the past three decades invasive group A streptococcal (iGAS) infections have been increasingly reported in industrialized nations. Amongst children varicella is recognized as a major risk factor for iGAS. We report a case of varicella complicated by Streptococcus pyogenes bacteremia and pyomyositis.
Case: A three year-old boy presented with high fever and bilateral knee and hip pain for 2 days. He had varicella for five days and was on aciclovir for two days. At admission, besides varicella lesions, gait impairment and extremely painful right thigh palpation, without edema or redness was noted.
Blood tests showed leucocitosis (19000 /uL; 74 % neutrophils), RCP 15.2 mg/dL, AST 86 UU/L but normal ALT, renal function and CK. A right hip arthritis and right lateralis vastus pyomyositis was evident on MRI.
The patient was started on flucloxacilin, which was adjusted to penicillin plus clindamicin after Streptococcus pyogenes isolation from blood cultures. Persistence of the abscess despite adequate antibiotics required drainage. There was progressive improvement and the patient was discharged after 14 days of intravenous treatment. Oral amoxicilin was prescribed for additional 7 days. Posterior reevaluation showed complete resolution of the clinical complaints.
Conclusion: Pyomyositis is a rare life-threatening infection often overlooked in the differential diagnosis of sudden musculoskeletal pain in children. In our case the absence of local inflammatory signs on presentation postponed diagnosis, later evidenced with MRI. Clinicians must be alert to this entity since prompt diagnosis and adequate antibiotic treatment is essential for successful treatment.
PalavrasChave: pyomyositis, invasive Group A streptococcal infections, iGAS.