Group A streptococcus and its antibiotic resistance.

Area of Science:

• Microbiology
• Infectious Diseases
• Pediatrics

Background:

• Acute pharyngo-tonsillitis in children is commonly caused by group A Streptococcus (GAS).
• GAS, traditionally viewed as extracellular, can internalize into host epithelial cells.
• Bacterial internalization is a key factor in GAS pathogenesis and infection persistence.

Purpose of the Study:

• To investigate the mechanisms of GAS internalization into human epithelial cells.
• To understand the role of bacterial internalization in antibiotic treatment failure and persistent carriage.
• To guide optimal antibiotic selection for GAS infections.

Main Methods:

• Review of recent studies on GAS adherence and internalization mechanisms.
• Analysis of the role of fibronectin-binding proteins (FnBPs) in bacterial entry.
• Evaluation of antibiotic treatment outcomes in relation to bacterial internalization.

Main Results:

• Fibronectin-binding proteins F1 and F2 facilitate GAS adherence and entry into epithelial cells.
• Strains expressing the F1 protein are linked to antibiotic treatment failure.
• Bacterial internalization contributes to persistent throat carriage and recurrent infections.

Conclusions:

• Internalization of GAS by epithelial cells is a significant factor in treatment failure and persistent carriage.
• Beta-lactam antibiotics may select for F1-positive GAS strains, exacerbating treatment issues.
• Macrolides and newer generation antibiotics are preferred for treating GAS infections due to their efficacy against internalized bacteria.