Invasive Streptococcus pyogenes infection: a case report

The Group A Streptococcus (GAS), also known as Streptococcus pyogenes (S. pyogenes), is a human pathogen causing various infections, ranging from mild, such as tonsillitis and impetigo, to severe and invasive conditions like septicemia and necrotizing fasciitis. Despite a decline in incidence and severity during the twentieth century due to antibiotics, there has been a reported increase in severe cases since the 1980s in industrialized countries. S. pyogenes is a human pathogen with a natural reservoir in the pharynx and skin, exhibits asymptomatic carriage in various body sites. It is responsible for a spectrum of clinical manifestations, from asymptomatic carriage to severe invasive infections. Transmission occurs through respiratory droplets or direct contact with skin lesions. Bacteriologically, S. pyogenes is a Gram-positive β-hemolytic streptococcus. This summary highlights a case of invasive Group A Streptococcus infection in a 28-year-old diagnosed at the microbiology laboratory of the Mohammed V Military Training Hospital in Rabat, Morocco. A 28-year-old patient, without any specific medical history, presented with acute febrile oligoarthritis. Following a recent flu-like syndrome and febrile tonsillitis, the patient experienced asymmetric inflammatory oligoarthralgia affecting the left knee, left ankle, and right shoulder, accompanied by functional impairment of the left lower limb. Upon admission, clinical examination revealed swelling, positive patellar tap, and sternal involvement. Laboratory and imaging findings indicated an abscessed collection in the left knee and anterior mediastinitis. Emergency aspirations revealed Group A Streptococcus, specifically Streptococcus pyogenes, leading to a diagnosis of septic arthritis. Dual antibiotic therapy and knee joint drainage resulted in symptom resolution after 45 days. The rise in severe Group A Streptococcus infection underscores the need for early detection and treatment. Widely sharing the French High Council for Public Health's antibiotic prophylaxis recommendations is crucial for awareness. Collaborating between clinicians and microbiologists is essential for effective management.