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Published on: April 7, 2015
Infective endocarditis with left to right intracardiac fistula due to Streptococcus anginosus - a rare complication
Robert Forster1, Fernando Peixoto Ferraz de Campos2, Silvana Maria Lovisolo3
1Department of Internal Medicine - Hospital das Clínicas - Faculdade de Medicina - Universidade de São Paulo, São Paulo/SP - Brazil.
Abstract:
Although infective endocarditis (IE) has been described in reports dating from the Renaissance, the diagnosis still challenges and the outcome often surprises. In the course of time, diagnostic criteria have been updated and validated to reduce misdiagnosis. Some risk factors and epidemiology have shown dynamic changes since degenerative valvular disease became more predominant in developed countries, and the mean age of the affected population increased. Despite streptococci have been being well known as etiologic agents, some groups, although rare, have been increasingly reported (e.g., Streptococcus milleri.) Intracardiac complications of IE are common and have a worse prognosis, frequently requiring surgical treatment. We report a case of a middle-aged diabetic man who presented with prolonged fever, weight loss, and ultimately severe dyspnea. IE was diagnosed based on a new valvular regurgitation murmur, a positive blood culture for Streptococcus anginosus, an echocardiographic finding of an aortic valve vegetation, fever, and pulmonary thromboembolism. Despite an appropriate antibiotic regimen, the patient died. Autopsy findings showed vegetation attached to a bicuspid aortic valve with an associated septal abscess and left ventricle and aortic root fistula connecting with the pulmonary artery. A large thrombus was adherent to the pulmonary artery trunk and a pulmonary septic thromboemboli were also identified.
Insights
Infective endocarditis (IE) diagnosis remains challenging. This case highlights severe complications of Streptococcus anginosus IE, emphasizing the need for vigilance in high-risk patients.
Area of Science:
- Cardiology
- Infectious Diseases
- Pathology
Background:
- Infective endocarditis (IE) diagnosis and outcomes present ongoing challenges.
- Epidemiology and risk factors for IE are evolving, with increasing prevalence in older populations and degenerative valve disease.
- While streptococci are common causes, rare groups like *Streptococcus milleri* are increasingly implicated.
Purpose of the Study:
- To report a complex case of infective endocarditis (IE).
- To illustrate the diagnostic challenges and severe complications associated with *Streptococcus anginosus* IE.
- To highlight the importance of prompt diagnosis and management in IE.
Main Methods:
- Case report of a middle-aged diabetic male with prolonged fever and dyspnea.
- Diagnosis of IE based on clinical presentation, positive blood cultures (*Streptococcus anginosus*), echocardiography, and pulmonary thromboembolism.
- Autopsy examination to confirm cardiac and vascular pathology.
Main Results:
- The patient presented with symptoms suggestive of IE, including fever and weight loss.
- Diagnosis confirmed IE with aortic valve vegetation, septal abscess, and a fistula between the left ventricle/aortic root and pulmonary artery.
- Despite antibiotic treatment, the patient experienced fatal pulmonary thromboembolism and septic emboli.
Conclusions:
- Infective endocarditis, particularly from *Streptococcus anginosus*, can lead to devastating intracardiac and vascular complications.
- Complex IE cases may require aggressive management, including surgical intervention, though outcomes can still be poor.
- This case underscores the critical need for early recognition and comprehensive evaluation of IE, even with atypical presentations.
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