How to diagnose and test male gonococci

Male gonococcal infection is a common purulent infection of the male urogenital system. Many people do not know how to test for male gonococci. In addition to some basic tests, patients can also do a secretion smear test, which is also the most suitable gonococcal test for men.

1. Smear examination of secretions

Mainly suitable for men.

(1) Clean the urethral opening with sterile saline.

(2) After wearing sterile gloves, use your fingers to squeeze out the pus from the base of the penis toward the urethral opening. Use a vaccination ring or cotton swab to pick up the pus and gently apply it on a glass slide. After it dries naturally, heat it to fix it, perform Gram staining, and then examine it under a microscope.

(3) When Gram-negative nephroticococci are found in polymorphonuclear leukocytes, a clear diagnosis can be made.

2. Isolation and culture of gonococci

(1) Sampling: When sampling from the urethra of male patients, a small cotton swab can be inserted into the urethra 2 to 4 cm and gently rotated to remove the secretions (which should contain a little mucosa).

(2) After the specimen is taken out, it is immediately inoculated into the culture medium. Currently, blood agar or chocolate agar medium with polymyxin added is commonly used.

(3) For the initial separation, a 5% to 10% CO2 candle should be used, the culture temperature should be 36°C, the relative humidity should be above 80%, and the culture should be carried out for 24 to 48 hours to observe the results.

(4) After 24 to 48 hours of culture on polymyxin B blood agar, gonococci can form round, raised, moist, smooth, translucent or grayish white colonies with petal-shaped edges and a diameter of 0.5 to 1.0 cm. They are sticky when touched with an inoculation loop. If the culture continues, the colony volume increases, the surface becomes rough, and the edges become wrinkled.

3. Identification of Neisseria gonorrhoeae - Oxidase test

(1) Prepare oxidase reagent: 0.5% to 1% dimethyl p-phenylenediamine hydrochloride aqueous solution.

(2) Add the solution to the suspected bacterial colonies and observe the color change. Alternatively, drop the reagent on a small piece of filter paper, then pick up the suspected bacterial colonies and let them come into contact with it to observe the color change.

(3) The colonies turn red 15 to 20 seconds after contact with the oxidase test, remain red for more than 30 seconds, then gradually turn purple, and finally turn black. This is a positive oxidase test, confirming that it is gonococci.