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Susceptibility to β-lactams in β-hemolytic streptococci
Laura Bonofiglio1, Paula Gagetti2, Gabriela García Gabarrot3
1Grupo STREP de la Sociedad Argentina de Bacteriología, Micología y Parasitología Clínicas (SADEBAC), División de la Asociación Argentina de Microbiología, Argentina; Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología y Biotecnología, Cátedra de Microbiología, Ciudad Autónoma de Buenos Aires, Argentina, CONICET, Argentina.
Abstract:
Group A (GAS), B (GBS), C (GCS) and G (GGS) β-hemolytic streptococci are important human pathogens. They cause infections of different severity and frequency. Nowadays, after 70 years of use, penicillin is still universally active against GAS, GCS and GGS. However, therapeutic failures have been recorded in 2-28% of pharyngitis cases (median: 12%) attributable to different causes. By contrast, some GBS with reduced susceptibility to penicillin have been described, especially in Japan. In this group of bacteria, it is important to highlight that confirmation by reference methods is mandatory when decreased susceptibility to penicillin is suspected as well as checked for the detection of the mechanisms involved.
Insights
Penicillin remains effective against most Group A, C, and G streptococci, but therapeutic failures in pharyngitis occur. Reduced penicillin susceptibility has been noted in some Group B streptococci, particularly in Japan.
Area of Science:
- Microbiology
- Infectious Diseases
- Antimicrobial Resistance
Background:
- Group A (GAS), B (GBS), C (GCS), and G (GGS) β-hemolytic streptococci are significant human pathogens causing varied infections.
- Penicillin, used for 70 years, shows universal activity against GAS, GCS, and GGS.
- Therapeutic failures in pharyngitis range from 2-28% (median 12%) due to diverse causes.
Purpose of the Study:
- To review the current status of penicillin susceptibility in β-hemolytic streptococci.
- To highlight the emergence of reduced penicillin susceptibility in GBS.
- To emphasize the need for confirmation and mechanism detection when reduced susceptibility is suspected.
Main Methods:
- Literature review on penicillin efficacy and resistance patterns in β-hemolytic streptococci.
- Analysis of reported therapeutic failures in streptococcal pharyngitis.
- Discussion of diagnostic approaches for reduced penicillin susceptibility.
Main Results:
- Penicillin remains a primary treatment for GAS, GCS, and GGS infections.
- A notable incidence of therapeutic failures in pharyngitis is attributed to various factors.
- Reduced penicillin susceptibility has been observed in some GBS strains, particularly in Japan.
Conclusions:
- Penicillin's efficacy is largely maintained against GAS, GCS, and GGS.
- The emergence of reduced penicillin susceptibility in GBS warrants attention.
- Confirmation of decreased susceptibility and investigation of underlying mechanisms are crucial for GBS infections.
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