Infections due to group C streptococci in man

Area of Science:

• Medical Microbiology
• Infectious Diseases

Background:

• Group C streptococci are common animal pathogens but infrequent human pathogens.
• Infections in humans are rare, with only eight cases identified in 150,000 blood cultures at Mayo Clinic (1968-1977).

Observation:

• This study describes severe infections in an immunosuppressed host, including endocarditis, meningitis, pneumonia, cellulitis, and bacteremia caused by group C streptococci.
• Previously reported cases are also reviewed.

Findings:

• Group C streptococcal infections, though severe, may respond well to penicillin therapy.
• Manifestations of cellulitis and pneumonia resemble those caused by group A streptococci.
• Meningitis is acute and severe, with slow response to antimicrobial treatment.
• Endocarditis caused by group D streptococci is acute, destructive, and linked to early cardiac decompensation.

Implications:

• Highlights the potential pathogenicity of group C streptococci in immunosuppressed populations.
• Emphasizes the importance of considering group C streptococci in severe infections, particularly in immunocompromised patients.
• Suggests penicillin as a primary treatment modality, while noting variable responses for meningitis.