Comparing First-Void Urine Specimens, Self-Collected Vaginal Swabs, and Endocervical Specimens To DetectChlamydia trachomatisandNeisseria gonorrhoeaeby a Nucleic Acid Amplification Test

Abstract

We set out to determine the prevalences of Chlamydia trachomatis and Neisseria gonorrhoeae by ligase chain reaction as well as to determine the prevalence of Trichomonas vaginalis by culture in a large and diverse national sample of non-health-care-seeking young women entering the military; we also sought to compare the abilities of three different techniques of collecting specimens (first-void urine, self-collected vaginal swab, and clinician-collected endocervical swab) to identify a positive specimen. A cross-sectional sample of young women was voluntarily recruited; as a part of their routine entry pelvic examination visit, they completed a selfadministered reproductive health questionnaire and provided first-void urine (used to detect C. trachomatis and N. gonorrhoeae) and self-collected vaginal swabs (used to detect C. trachomatis, N. gonorrhoeae, and T. vaginalis). The number of positive tests divided by the number of sexually active women screened by each sampling method determined the rates of prevalence. The rate of infection with any of the three sexually transmitted diseases (STDs) tested was 14.1%. The total positive rates for each STD (identified by >1 specimen) were the following: for C. trachomatis, 11.6%; N. gonorrhoeae, 2.4%; and T. vaginalis, 1.7%. The proportions of positives identified by specimen type were, for C. trachomatis and N. gonorrhoeae, respectively, endocervix, 65 and 40%; urine, 72 and 24%; and vagina, 81 and 72%. The proportions of positives when specimen results were combined were, for C. trachomatis and N. gonorrhoeae, respectively, cervix plus urine, 86 and 49%; cervix plus vagina, 91 and 93%; and vagina plus urine, 94 and 79%. We concluded that STDs were epidemic in this population. Self-collected vaginal swabs identified the highest number of positive test results among single specimens, with the combined cervix-vagina results identifying the highest number of positive results. Self-collected vaginal swab collections are a feasible alternative to cervical specimen collections in this population, and the use of multiple types of specimens increases the positive yield markedly.Chlamydia trachomatis remains epidemic among sexually active young women (5). Health policy organization guidelines recommend annual chlamydial screening of sexually active adolescent and young adult females (1, 2, 29). Nucleic acid amplification technique (NAAT) applied to endocervical samples has proven to be a sensitive nonculture method to screen young women for C. trachomatis, with sensitivities ranging from 75 to 100% and with many reporting sensitivities greater than 90% (6,7,21,22,27,30,31). A further advance has been the application of the NAAT to first-void urine (FVU) samples to detect C. trachomatis with reported sensitivities of 50 to 95% (6,7,15,22,25,27,30,31). This noninvasive form of specimen collection has been shown to be a cost-effective tool for chlamydial screening when compared to endocervical swabs because such collections do not require invasive pelvic examinations (24). Finally...

Genital Chlamydia trachomatis infections

“…La diagnosi di infezione da C.t., basata sull'utilizzo del tampone vaginale, si attesta su livelli di efficacia pari o superiori ai più tradizionali mezzi di indagine mediante coltura ed ai più moderni metodi di indagine mediante tecniche di amplificazione su campioni di urine o tamponi cervicali. Diversi studi (96,103) hanno confermato la validità dell'autoprelievo vaginale confrontato con prelievi endocervicali e vaginali eseguiti da personale specializzato dimostrando rispettivamente una sensibilità del 100% ed una specificità del 98.5%. L'alta sensibilità dei NAATs permette inoltre di utilizzare "pools" di campioni per ridurre i costi.…”

Self‐administered Vaginal Swabs Are a Feasible Alternative to Physician‐assisted Cervical Swabs for Sexually Transmitted Infection Screening in the Emergency Department

“…[2][3][4][5] However, evidence indicates that SAVS may perform better than urine samples. [6][7][8] Knox et al 8 used PCR for SAVS and first-void urines (FVU) and found that SAVS were more sensitive for C. trachomatis and N. gonorrhoeae. Shafer et al 7 compared FVU, SAVS, and PACS and found that SAVS detected the highest number of positive cases for C. trachomatis and N. gonorrhoeae from a single specimen.…”

“…[6][7][8] Knox et al 8 used PCR for SAVS and first-void urines (FVU) and found that SAVS were more sensitive for C. trachomatis and N. gonorrhoeae. Shafer et al 7 compared FVU, SAVS, and PACS and found that SAVS detected the highest number of positive cases for C. trachomatis and N. gonorrhoeae from a single specimen. Of note, a study investigating the feasibility of STI screening in the ED by urine testing found that 15% of eligible patients were not screened because they could not provide a urine sample.…”

“…[2][3][4] Other studies (non-ED based) have shown that vaginal swab specimens perform as well as, or better than, urine or cervical samples for STI detection. [5][6][7] To the best of our knowledge, self-administered vaginal swabs (SAVS) have only been evaluated in non-ED settings. Our objective was to examine the feasibility of SAVS in identifying C. trachomatis and N. gonorrhoeae in female ED patients.…”

Variability of Vaginal pH Determination by Patients and Clinicians

“…Self-collected vaginal samples may be as accurate as clinician-obtained specimens for diagnosing various sexually transmitted infections including Neis-seria gonorrhea, Chlamydia trachomatis, Trichomonas vaginalis, and human papillomavirus. [7][8][9][10][11][12][13] Moreover, self-sampling the vagina seems to be very acceptable to women of multiple ethnic groups. 8,9,[13][14][15][16][17] Women have also demonstrated a willingness to obtain a self-sample of vaginal secretions for Gram stain detection of bacterial vaginosis.…”