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Be careful about MICs to amoxicillin for patients with Streptococci-related infective endocarditis
B Pilmis1, J Lourtet-Hascoët2, O Barraud3
1Equipe mobile de microbiologie Clinique, Groupe Hospitalier Paris Saint-Joseph, Paris, France.
Background:
A variety of microorganisms can cause infective endocarditis (IE), with Staphylococci and Streptococci accounting for the majority of cases. Streptococci are a common cause of community-acquired IE but few studies have focused on this subgroup of endocarditis.
Methods:
A retrospective multicentre study was conducted between 2012 and 2017 in 12 hospital centres in France. Data were extracted from the local diagnosis-related group database and matched with microbiological results. After identification, the records were retrospectively analysed.
Results:
A total of 414 patients with streptococcal endocarditis were included. The patients were predominantly male (72.8%) and the median age was 73.2 years (interquartile range [IQR] 61.3-80.9). The majority of patients (70.6%) had native valve endocarditis. Embolic complications were seen in 38.8% of patients. Viridans group Streptococci (VGS) and bovis-equinus group Streptococci (BGS) accounted for 52.4% and 34.5% of isolated strains, respectively. Minimum inhibitory concentrations (MICs) of amoxicillin were <0.125, 0.125-2 and >2 mg/L for 59.6%, 27% and 1% of isolates, respectively. In-hospital mortality for patients with Streptococci-related IE was 17.8%. In multivariate analysis, the only factor associated with in-hospital mortality was MIC for amoxicillin between 0.25 and 2 mg/L (P = 0.04; OR = 2.23 [95% confidence interval (CI) 1.03-4.88]) whereas performance of cardiac surgery for IE was a protective factor (P = 0.001, OR = 0.23 [95% CI 0.1-0.56]).
Conclusions:
IE remains a serious and deadly disease despite recent advances in diagnosis and treatment. Adaptation of antibiotic doses to MICs for amoxicillin and surgery may improve patient outcome.
Insights
Infective endocarditis (IE) caused by Streptococci is serious, with high mortality. Amoxicillin minimum inhibitory concentrations (MICs) and cardiac surgery significantly impact patient outcomes.
Area of Science:
- Infectious Diseases
- Cardiology
- Microbiology
Background:
- Infective endocarditis (IE) is a severe infection, often caused by Staphylococci and Streptococci.
- Streptococci are a frequent cause of community-acquired IE, yet specific research on this subgroup is limited.
Purpose of the Study:
- To investigate the clinical characteristics, microbiological features, and outcomes of patients with streptococcal infective endocarditis.
- To identify factors associated with in-hospital mortality in this patient population.
Main Methods:
- A retrospective multicenter study was conducted in 12 French hospitals from 2012 to 2017.
- Data were collected from diagnosis-related group databases and matched with microbiological results for analysis.
Main Results:
- The study included 414 patients with streptococcal IE, predominantly male (72.8%) with a median age of 73.2 years.
- Viridans group Streptococci (VGS) and bovis-equinus group Streptococci (BGS) were the most common isolates (52.4% and 34.5%).
- In-hospital mortality was 17.8%, associated with amoxicillin MICs between 0.25-2 mg/L (OR=2.23) and reduced by cardiac surgery (OR=0.23).
Conclusions:
- Streptococcal IE remains a critical condition with significant mortality.
- Tailoring antibiotic therapy based on amoxicillin MICs and considering cardiac surgery are crucial for improving patient outcomes.
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