Trimethoprim as an additional selective agent in media for the isolation of N. gonorrhoeae

Area of Science:

• Microbiology
• Clinical Diagnostics

Background:

• Routine isolation of Neisseria gonorrhoeae (gonococcus) is crucial for diagnosing gonorrhea.
• Existing selective media may face challenges with overgrowth by commensal organisms, impacting diagnostic accuracy.

Purpose of the Study:

• To evaluate the efficacy of incorporating trimethoprim into selective media for improved gonococcal isolation.
• To assess the benefits of trimethoprim-supplemented media over conventional methods.

Main Methods:

• Incorporation of trimethoprim into selective media bases: saponin-lysed blood agar and chocolate agar.
• Comparative analysis of trimethoprim-supplemented media against existing selective media for gonococcus recovery.

Main Results:

• Trimethoprim effectively inhibited Proteus mirabilis and other commensal organisms.
• Selective media with trimethoprim demonstrated increased recovery rates of gonococcus.
• Enabled plating of multiple swabs onto a single selective plate, irrespective of the source.

Conclusions:

• Trimethoprim-supplemented selective media offer a significant advantage for routine gonococcus isolation.
• This approach enhances diagnostic efficiency by improving pathogen recovery and reducing contamination.