The direct Gram stain of a urethral discharge from males with urethritis is a rapid and sensitive screening test for Neisseria gonorrhoeae infection. This image shows gram-negative diplococci within polymorphonuclear leukocytes. Cocci are 0.6 to 1.0 mm in diameter and can occur singly, but are more often found in pairs with adjacent sides flattened (diplococci). Bacterial culture and carbohydrate fermentation studies provide definitive identification of the organism. N. gonorrhoeae is the etiological agent of the sexually transmitted disease gonorrhea. Infections caused by this organism are localized to the mucosal surfaces in the area of initial exposure to the organism (e.g., cervix, conjunctiva, pharyngeal surface, anorectal area, or urethra of males). The organism may also be spread from infected mother to newborn during birth.
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