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Aortic valve infective endocarditis due to Streptococcus pyogenes : A case report
Gabriella Primera1, Karen Hogan2, Hans Schlecht3
1Department of Internal Medicine, University of Massachusetts Chan Medical School, Baystate Medical Center, Springfield, MA, USA.
Abstract:
Group A Streptococcus is a common cause of pharyngitis, scarlet fever, glomerulonephritis, and various skin infections. However, there have only been a few reports of Group A Streptococcus (GAS) associated with infective endocarditis. We present a case of a 31-year-old male who presented to the hospital with a few days of weakness and myalgias after recently receiving treatment with azithromycin for GAS pharyngitis as an outpatient. The patient was admitted to the intensive care unit in septic shock from Group A beta-hemolytic Streptococcus bacteremia and acute hypoxic respiratory failure. He was found to have new severe aortic insufficiency from infective endocarditis. He underwent urgent partial aortic valve annuloplasty reconstruction and incision and drainage of root abscess with intraoperative cultures growing gram positive cocci consistent with GAS. The majority of cases of infective endocarditis are caused by Staphylococcus aureus, virdians group Streptococci and Streptococcus gallolyticus, while Streptococcus pneumoniae and Streptococcus pyogenes have the lowest prevalence of infective endocarditis. Penicillin remains the first line treatment for GAS pharyngitis. However, in cases of severe penicillin allergy, macrolides should be avoided given the increasing rate of macrolide resistance GAS strains. This case emphasizes the importance of using beta-lactams as first line therapy for GAS pharyngitis to avoid harmful complications and infection recurrence.
Insights
Group A Streptococcus (GAS) can cause severe infections like endocarditis. This case highlights the risk of using macrolides for GAS pharyngitis, recommending beta-lactams to prevent complications.
Area of Science:
- Infectious Diseases
- Cardiology
- Microbiology
Background:
- Group A Streptococcus (GAS) commonly causes pharyngitis and skin infections.
- Infective endocarditis is rarely associated with GAS, with Staphylococcus aureus and other Streptococci being more prevalent.
- Macrolide resistance in GAS is increasing, posing treatment challenges.
Observation:
- A 31-year-old male developed septic shock and acute hypoxic respiratory failure due to GAS bacteremia.
- The patient presented with new severe aortic insufficiency secondary to infective endocarditis after outpatient azithromycin treatment for GAS pharyngitis.
- Urgent aortic valve reconstruction and abscess drainage were performed, with cultures confirming GAS.
Findings:
- This case demonstrates a rare but severe complication of GAS infection.
- The patient's presentation suggests potential macrolide treatment failure or resistance in GAS pharyngitis, leading to invasive disease.
- GAS endocarditis, though uncommon, can lead to life-threatening conditions requiring prompt surgical and medical intervention.
Implications:
- Emphasizes the critical importance of beta-lactams as first-line therapy for GAS pharyngitis.
- Highlights the need to consider antibiotic resistance patterns when treating GAS infections, especially in patients with severe penicillin allergies.
- Underscores the potential for GAS to cause severe invasive infections like endocarditis, necessitating vigilant diagnosis and management.
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Endocarditis II: Clinical Features of Infective Endocarditis
Endocarditis III: Medical Management
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Aortic Regurgitation I: Introduction

