Isolation of Neisseria gonorrhoeae is best enhanced by which condition?

• A. Cold enrichment
• B. Increased CO2 incubation
• C. From contaminated sites is easier on CIN agar
• D. Refrigeration of clinical specimen before culturing has no effect

Answer: (B)

Neisseria gonorrhoeae is capnophilic, meaning it grows best in a carbon dioxide–rich environment. This fastidious organism prefers enriched media such as chocolate or Thayer-Martin agar and is typically incubated at body-like temperatures (about 35–37°C) with elevated CO2 (roughly 5–10%). The higher CO2 level helps maintain the microaerophilic conditions the bacteria favor and promotes more robust colony formation, making isolation more reliable. Cold enrichment or refrigeration hampers its viability and isn’t helpful for recovery. CIN agar is not suitable for gonorrhoeae because it’s designed for other organisms and contains inhibitors that hinder its growth. So, providing increased CO2 during incubation best enhances isolation.