[Endocarditis caused by group B streptococci in adults]

Area of Science:

• Cardiology
• Infectious Diseases
• Bacteriology

Background:

• Group B Streptococcus (GBS), or Streptococcus agalactiae, is a significant pathogen, particularly in neonates.
• Infectious endocarditis (IE) is a serious infection of the heart valves.
• The role of GBS as a cause of IE in nonpregnant adults is less understood.

Purpose of the Study:

• To investigate the clinical characteristics, treatment strategies, and outcomes of Streptococcus agalactiae endocarditis in nonpregnant adults.
• To determine the incidence and risk factors associated with GBS endocarditis in this population.

Main Methods:

• A retrospective review of all cases of Streptococcus agalactiae endocarditis diagnosed using Duke criteria between 1980 and 1994.
• Inclusion criteria involved patients admitted to a 1000-bed university hospital with a prospective bacteremia surveillance system.
• Data collected included patient demographics, underlying conditions, valve involvement, treatment, and mortality.

Main Results:

• Nine episodes of S. agalactiae endocarditis were identified, representing 2.6% of all native valve endocarditis cases.
• The affected patients had an average age of 60 years, with underlying conditions or valvulopathy noted in some.
• The aortic and mitral valves were most commonly involved, and all isolates were penicillin-susceptible. Overall mortality was 11%.

Conclusions:

• Streptococcus agalactiae is an uncommon cause of infectious endocarditis in nonpregnant adults.
• Combined surgical and antibiotic therapy may be associated with improved outcomes and reduced mortality rates for GBS endocarditis.