Streptococcal antibody: as an indicator of tonsillectomy

Area of Science:

• Immunology
• Pediatric Otolaryngology
• Infectious Diseases

Background:

• Antibodies to streptolysin-O (ASO) are markers for streptococcal infections.
• Tonsillectomy is a common surgical procedure for various throat conditions.

Purpose of the Study:

• To investigate the significance of ASO titers in relation to tonsillectomy decisions.
• To evaluate the correlation between ASO titers and recurrent tonsillitis or tonsillar hypertrophy.

Main Methods:

• Analysis of ASO titers in a large cohort of school children.
• Comparison of ASO titers measured by Todd units and ELISA (IgG and IgM subclasses).
• Correlation analysis between ASO titers, recurrent tonsillitis, and tonsillar hypertrophy.

Main Results:

• Normal ASO limits varied annually, with >333 U considered abnormal.
• A high ASO titer (>833 U) was found in only 12 of 143 cases with recurrent tonsillitis.
• No correlation was observed between tonsillar hypertrophy and streptococcal antibody levels.
• ELISA IgG-ASO correlated with Todd units (r=0.69), but ELISA IgM-ASO did not.
• Elevated IgM-ASO levels were associated with early streptococcal infections, focal infections, and carrier states.

Conclusions:

• High ASO titers (IgG and IgM) serve as an indicator for tonsillectomy.
• ASO titer alone may not be sufficient for diagnosing recurrent tonsillitis or determining the need for tonsillectomy.
• ELISA IgM-ASO may be useful for detecting early or subclinical streptococcal infections.