title: Diagnosing non-gonococcal urethritis: the gram-stained urethral smear in perspective.
abstract: The value of microscopy of a Gram-stained urethral smear in the diagnosis of non-gonococcal urethritis and chlamydial urethral infection was assessed in 153 men attending a department of genitourinary medicine. A mean of more than 4 polymorphs in 5 fields (x1000) was considered to be abnormal. In the diagnosis of urethritis, the sensitivity (94%), specificity (91%), positive predictive value (93%) and negative predictive value (93%) were high. In the diagnosis of chlamydial infection, sensitivity (91%) and negative predictive value (96%) were high, but specificity (68%) and positive predictive value (46%) were low. In men with symptoms of genitourinary infection, the sensitivity (96.7%) and negative predictive value (97.4%) of the Gram-stained urethral smear in the diagnosis of chlamydial infection was comparable with modern chlamydial antigen detection tests.
authors.affiliation: Department of Genitourinary Medicine, Royal South Hants Hospital, Southampton, UK.
authors.forename: P M
authors.initials: PM
authors.lastname: Terry
authors.forename: S
authors.initials: S
authors.lastname: Holland
authors.forename: D
authors.initials: D
authors.lastname: Olden
authors.forename: S
authors.initials: S
authors.lastname: O'Connell
mesh_terms: D002690:Chlamydia Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology; D002692:Chlamydia trachomatis; D004739:England / Q000453:epidemiology; D005069:Evaluation Studies as Topic; D005840:Gentian Violet; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D009504:Neutrophils / Q000737:chemistry; D010619:Phenazines; D012680:Sensitivity and Specificity; D014526:Urethritis / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology
chemical_list: C035863:Gram's stain; D010619:Phenazines; D005840:Gentian Violet