A simple broth-disk method to determine the minimum inhibitory concentration of ceftriaxone on Salmonella enterica...

Area of Science:

• Microbiology
• Infectious Diseases
• Antimicrobial Resistance

Background:

• Salmonella enterica serovar Typhi and Paratyphi pose significant challenges due to resistance to common antibiotics like fluoroquinolones and cephalosporins.
• Accurate determination of antibiotic susceptibility, specifically minimum inhibitory concentration (MIC), is crucial for effective treatment of typhoid and paratyphoid fevers.

Purpose of the Study:

• To introduce and evaluate a simple broth-disk method for determining the MIC of ceftriaxone.
• To assess the reliability and cost-effectiveness of this method compared to conventional techniques.

Main Methods:

• The study utilized sixteen strains of Salmonella Typhi and two strains each of Salmonella Paratyphi A and B.
• Minimum inhibitory concentration (MIC) of ceftriaxone was determined using both the novel broth-disk method and the established broth macrodilution method.
• Results from both methods were compared for accuracy and consistency.

Main Results:

• All Salmonella strains tested demonstrated susceptibility to ceftriaxone.
• The results obtained from the broth-disk method showed strong agreement with the conventional broth macrodilution method.
• The broth-disk method proved to be a reliable alternative for MIC determination.

Conclusions:

• The broth-disk method is a simple, reliable, and cost-effective technique for determining the MIC of ceftriaxone against Salmonella Typhi and Paratyphi A.
• This method offers a practical approach for clinical laboratories to assess antibiotic susceptibility in these important enteric pathogens.