Gram-stained smear in the diagnosis of acute urethritis: is it coming to an end?

Abstract

Acute urethritis is the most common infection of the male genital tract. Approximately 89 million new cases of non-gonococcal urethritis (NGU) and 62 million new cases of gonococcal ure-thritis (GU) are reported globally every year, and these numbers continue to increase 1 . Acute urethritis is most commonly caused by sexually transmitted pathogens. The three cardinal symptoms are urethral discharge, dysuria, and itching. The traditional diagnostic method for acute urethritis is a Gram-stained smear (GSS) of urethral discharge. GSS is widely used because it is of low cost and is easy to perform. Not only does GSS diagnose acute urethritis but it also allows the dichotomization of cases as GU caused by Neisseria gonorrhoeae with the detection of gram-negative diplococci or NGU in their absence 2 . However, GSS is a test susceptible to inter-and intra-observer errors. In the classical approach, the treatment of acute urethritis is managed through GSS. GSS inevitably leads the clinician to empirical treatment, especially in cases of NGU, as the specific identification of NGU pathogens by conventional methods is a long process. However, treatment failure occurs in up to 20% of NGU patients who receive empirical treatment based on the results of GSS 3 . Moreover, empirical treatment practices also contribute to the development of resistant strains. Antibiotic resistance in N. gonorrhoeae and Mycoplasma genitalium is a serious public health problem 4 , and M. genitalium alone is responsible for 41% of recurrent urethritis cases 5 . The