P2.M243: Novel Presentation of Invasive Group A Streptococcus Infection in a Pediatric Patient

Introduction: Group A streptococcus (GAS) is a facultative anaerobic gram-positive coccus that commonly causes pharyngitis and cutaneous infections. Although less common, invasive GAS (iGAS) infection is a life-threatening condition defined as GAS isolation from a normally sterile site. We present a unique presentation of iGAS in a previously healthy pediatric patient.

Case Description: A previously healthy 19-month-old, full-term male presented with 6 days of fever, cough, rhinorrhea, progressive neck stiffness, and difficulty walking with a recent upper respiratory infection. He was initially evaluated at two separate urgent care visits and sent home for presumed viral etiology. Due to persistent fevers and inability to bear weight, the patient re-presented to the emergency room for further evaluation. Upon arrival, he was ill appearing, tachycardic, febrile, hypotensive, had diffuse rash, peripheral edema, and oral mucosal erythema. Blood cultures were obtained and intravenous ceftriaxone and vancomycin infusion were empirically started for septic shock. Lumbar puncture was deferred given the patient was at neurological baseline. He also received intravenous immunoglobulin and aspirin for concern for incomplete Kawasaki disease. However, on hospital day 2, blood culture grew Streptococcus pyogenes and parenteral antibiotics were transitioned to targeted GAS therapy with clindamycin and penicillin. Areas of cellulitis and myositis improved, however other foci, including his right neck, persisted. CT neck illustrated right trapezius abscess requiring surgical incision and drainage. Workup for underlying rheumatologic conditions and immune deficiencies was negative. After two weeks of parenteral antibiotics, he became afebrile and discharged on oral amoxicillin and clindamycin for a tentative 4-week course.

Discussion: In the last three decades, the frequency of invasive GAS has increased in both general and pediatric populations. iGAS infection has a high fatality rate due to the production of exotoxins which behave as superantigens in about 10% of cases. Our patient did not have a clear source of infection and likely developed GAS pharyngitis and subsequent invasive disease due to delay in identification of etiology and initiation of antimicrobial therapy. The patient’s concurrent viral illness may have also increased risk of iGAS. Lumbar puncture should have been performed given the patient’s extremity weakness and protracted fever, as cerebral abscess from GAS can present with motor deficits and lead to increased morbidity and mortality. With its increasing incidence and severity, novel strategies including GAS vaccine development would be instrumental in preventing severe iGAS infection.

Conclusion: To prevent delays in medical management, further investigation is needed to identify the various presentations of iGAS for early recognition and treatment. Additionally, its high mortality rate and increasing incidence prompt a need to further delineate its pathogenesis and risk factors as well as develop evidence-based solutions and management strategies.