Tricuspid valve infective endocarditis complicated with multiple lung abscesses and thoracic empyema as different pathogens: a case report

Septic Shock Secondary to Tricuspid Valve Vegetation Requiring Surgical Debulking

Tricuspid valve endocarditis is increasing in incidence owing to the prevalent use of intravenous substances. Although most patients respond well to intravenous antibiotics over the course of six weeks, some patients require surgical intervention. A multilayered approach to diagnosis with both transthoracic and transesophageal echocardiography (TEE) is recommended for optimal diagnosis and management. In this article, we report a case of septic shock resulting from tricuspid valve infective endocarditis in a young woman with a history of intravenous drug use who ultimately required cardiothoracic surgical intervention for tricuspid valve vegetation. The sensitivity and specificity of TEE for vegetation on the native valves are about 96% and 90%, respectively. Timely surgical intervention may increase the likelihood of tricuspid valve repair by preventing further destruction of leaflet tissue. Transthoracic echocardiogram (TTE) and TEE have complementary roles in the diagnosis and evaluation of endocarditis. With this case report, we emphasize the importance of multimodality imaging and early surgical intervention to prevent further embolism and destruction of tricuspid valve leaflet tissue.

A Rare Case of Blood Culture-Negative Isolated Pulmonic Valve Endocarditis Causing Empyema

Right-sided native valve infective endocarditis (IE) refers to IE involving the tricuspid or pulmonic valve. The most common factors causing right-sided IE include intravenous drug use, intracardiac device, and central venous catheters. Isolated pulmonic valve IE has only been reported in less than 2% of all IE cases. We present a unique case of a patient with a history of poor oral hygiene found to have isolated blood culture-negative pulmonic valve IE, who subsequently developed empyema positive for Streptococcus constellatus.

Drug use-related right-sided infective endocarditis complicated by empyema and bronchopleural fistula

Right-sided infective endocarditis is frequently accompanied by septic pulmonary emboli, which may result in a spectrum of respiratory complications. We present the case of a 25-year-old woman diagnosed with infective endocarditis secondary to intravenous drug use. During a long and arduous hospital course, the patient developed empyema with bronchopleural fistula, representing severe but uncommon sequelae that may arise from this disease process. She was treated with several weeks of antibiotics as well as surgical thorascopic decortication and parietal pleurectomy.

Pulmonary complications observed in patients with infective endocarditis with and without injection drug use: An analysis of the National Inpatient Sample

Background

The impact of cardiovascular and neurologic complications on infective endocarditis (IE) are well studied, yet the prevalence and significance of pulmonary complications in IE is not defined. To better characterize the multifaceted nature of IE management, we aimed to describe the occurrence and significance of pulmonary complications in IE, including among persons with IE related to drug use.

Methods

Hospitalizations of adult (≥18 years old) patients diagnosed with IE were identified in the 2016 National Inpatient Sample using ICD-10 codes. Multivariable logistic and linear regression were used to compare IE patient outcomes between those with and without pulmonary complications and to identify predictors of pulmonary complications. Interaction terms were used to assess the impact of drug-use IE (DU-IE) and pulmonary complications on inpatient outcomes.

Results

In 2016, there were an estimated 88,995 hospitalizations of patients diagnosed with IE. Of these hospitalizations,15,490 (17%) were drug-use related. Drug-use IE (DU-IE) had the highest odds of pulmonary complications (OR 2.97, 95% CI 2.50, 3.45). At least one pulmonary complication was identified in 6,580 (7%) of IE patients. DU-IE hospitalizations were more likely to have a diagnosis of pyothorax (3% vs. 1%, p<0.001), lung abscess (3% vs. <1%, p<0.001), and septic pulmonary embolism (27% vs. 2%, p<0.001). Pulmonary complications were associated with longer average lengths of stay (CIE 7.22 days 95% CI 6.11, 8.32), higher hospital charges (CIE 78.51 thousand dollars 95% CI 57.44, 99.57), more frequent post-discharge transfers (acute care: OR 1.37, 95% CI 1.09, 1.71; long-term care: OR 2.19, 95% CI 1.83, 2.61), and increased odds of inpatient mortality (OR 1.81 95% CI 1.39, 2.35).

Conclusion and relevance

IE with pulmonary complications is associated with worse outcomes. Patients with DU-IE have a particularly high prevalence of pulmonary complications that may require timely thoracic surgical intervention, likely owing to right-sided valve involvement. More research is needed to determine optimal management strategies for complications to improve patient outcomes.

Contribution of Severe Dental Caries Induced by Streptococcus mutans to the Pathogenicity of Infective Endocarditis

Streptococcus mutans, a major pathogen of dental caries, is regarded as a causative agent of infective endocarditis (IE), which mainly occurs in patients with underlying heart disease. However, it remains unknown whether severe dental caries that extend to pulp space represent a possible route of infection. In the present study, we evaluated the virulence of S. mutans for IE development using rats with concurrent severe dental caries and heart valve injury. Dental caries was induced in rats through the combination of a caries-inducing diet and the administration of S. mutans into the oral cavity. Then, the heart valves of a subset of rats were injured using a sterile catheter and wire under general anesthesia. The rats were euthanized at various times with various stages of dental caries. The number of teeth affected by dental caries with pulp exposure was increased in the rats in a time-dependent manner. S. mutans was recovered from injured heart tissue, which was mainly observed in rats with higher number of S. mutans bacteria in mandibular bone and a larger number of teeth in which caries extended to pulp. Dental caries was more severe in rats with heart injury than in rats without heart injury. Sequencing analysis targeting 16S rRNA revealed that specific oral bacteria appeared only in rats with heart injury, which may be related to the development of dental caries. Our findings suggest that dental caries caused by the combination of S. mutans infection and sucrose intake may contribute to S. mutans colonization in injured heart tissue.