Browsing by Author "Mena, Leandro"

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    Clinical Evaluation of the BD ProbeTec™ Neisseria gonorrhoeae Qx Amplified DNA Assay on the BD Viper™ System With XTR™ Technology
    (Wolters Kluwer, 2012) Van Der Pol, Barbara; Taylor, Stephanie N.; LeBar, William; Davis, Thomas; Fuller, Deanna; Mena, Leandro; Fine, Paul; Gaydos, Charlotte A.; Martin, David H.; Hook, Edward W., III; Medicine, School of Medicine
    Background: The excellent sensitivity and specificity of commercially available nucleic acid amplification tests (NAATs) for the identification of Neisseria gonorrhoeae have been demonstrated. This study evaluated the performance of the BD ProbeTec™ N. gonorrhoeae Q (GCQ) Amplified DNA Assay on the BD Viper™ System with XTR™ Technology in a multicenter study. Methods: Specimens were collected at 7 geographically diverse clinical sites from 1846 women and men attending sexually transmitted disease, family planning, and obstetrics and gynecology clinics. There were 1768 evaluable participants, 994 women and 774 men. GCQ results from female endocervical, self-collected vaginal, male urethral swab specimens, and male and female neat (unpreserved) urine specimens, as well as those obtained using the urine preservative transport (UPT) tube for the GCQ assay were compared with patient infected status (PIS). For each participant, PIS was determined based on the combined results from the reference assays Aptima Combo 2® (AC2) and BD ProbeTec™ ET GC Amplified DNA Assay (PT). Results: The sensitivity versus PIS for endocervical, vaginal, and female UPT urine, and female neat urine samples was 98.5%, 100.0%, 98.5%, and 96.9%, respectively; the specificity was 99.7%, 99.1%, 99.7%, and 99.5%, respectively. The sensitivity versus PIS for male urethral swabs and both male UPT and neat urine was 100.0%, with specificities of 99.1% for the urethral swab and UPT urine and 98.9% for the neat urine. The overall GCQ assay performance was not statistically different from that of AC2 or PT. Conclusions: The GCQ assay demonstrated performance characteristics comparable with other commercially available nucleic acid-based tests such as AC2 and PT. Vaginal swabs, endocervical swabs, urethral swabs, and urine specimens may all be used for gonorrhea screening.
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    Evaluation of the Performance of a Point-of-Care Test for Chlamydia and Gonorrhea
    (JAMA Network, 2020-05) Van Der Pol, Barbara; Taylor, Stephanie N.; Mena, Leandro; Lebed, Joel; McNeil, Candice Joy; Crane, LaShonda; Ermel, Aaron; Sukhija-Cohen, Adam; Gaydos, Charlotte A.; Medicine, School of Medicine
    Importance: Rates of chlamydial and gonococcal infection continue to increase in the United States, as do the associated costs of untreated infections. Improved diagnostic technologies that support testing and treating in 1 clinical visit are critical to advancing efforts to control the rates of chlamydial and gonococcal infection. Objective: To evaluate the clinical performance of a point-of-care (POC) molecular diagnostic assay for the detection of chlamydia and gonorrhea. Design, setting, and participants: A noninterventional, cross-sectional clinical study was conducted from September 18, 2018, through March 13, 2019, at sexually transmitted infection (STI), HIV, family planning, and obstetrics and gynecology clinics where STI screening is routine, using a convenience sample and comparing commercially available assays with a new 30-minute POC assay. Patients included were those eligible for STI screening or diagnostic testing who had not taken antibiotics effective against chlamydia or gonorrhea within the previous 28 days. Four vaginal swab samples were collected from women and a first-catch urine sample was obtained from men. Main outcomes and measures: A composite infection status was used to classify participants as infected if 2 or more comparator results were positive, as not infected if 2 or more comparator samples were negative, and as unevaluable if 1 result was invalid and the other 2 results did not agree with each other. Results: Swab samples from 1523 women (median age, 27 years [interquartile range, 17-37 years]), 817 (53.6%) of whom presented with symptoms, and 922 men (median age, 29 years [interquartile range, 17-41 years]), 308 (33.4%) of whom were symptomatic, were tested. For chlamydia, sensitivity of the new POC assay was 96.1% (95% CI, 91.2%-98.3%) for women and 92.5% (95% CI, 86.4%-96.0%) for men. For gonorrhea, sensitivity estimates were 100.0% (95% CI, 92.1%-100.0%) for women and 97.3% (95% CI, 90.7%-99.3%) for men. For chlamydia, specificity of the new POC assay was 99.1% (95% CI, 98.4%-99.5%) for women and 99.3% (95% CI, 98.4%-99.7%) for men. For gonorrhea, specificity estimates were 99.9% (95% CI, 99.5%-100%) for women and 100% (95% CI, 95.5%-100%) for men. Non-laboratory-trained personnel performed 94.8% of all tests (2318 of 2445) during the study. Conclusions and relevance: This study suggests that self-obtained vaginal swab samples were associated with performance equivalent to laboratory-based molecular diagnostics, which can support use of this POC assay in many settings. The availability of an easy-to-use, rapid (30-minute) molecular test for accurate detection of chlamydia and gonorrhea has the power to facilitate testing and treatment in a single patient visit for these STIs.
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    Trichomonas vaginalis Detection in Urogenital Specimens from Symptomatic and Asymptomatic Men and Women by Use of the cobas TV/MG Test
    (American Society for Microbiology, 2021) Van Der Pol, Barbara; Rao, Arundhati; Nye, Melinda B.; Chavoustie, Steven; Ermel, Aaron; Kaplan, Clair; Eisenberg, David; Chan, Philip A.; Mena, Leandro; Pacheco, Sixto; Waites, Ken B.; Xiao, Li; Krishnamurthy, Smitha; Mohan, Ruchika; Bertuzis, Rasa; McGowin, Chris L.; Arcenas, Rodney; Marlowe, Elizabeth M.; Taylor, Stephanie N.; Medicine, School of Medicine
    Trichomonas vaginalis is a prevalent sexually transmitted infection (STI). Diagnosis has historically relied on either microscopic analysis or culture, the latter being the previous gold standard. However, these tests are not readily available for male diagnosis, generally only perform well for symptomatic women, and are not as sensitive as nucleic acid amplification tests (NAATs). Men are largely asymptomatic but carry the organism and transmit to their sexual partners. This multicenter, prospective study evaluated the performance of the cobas T. vaginalis/Mycoplasma genitalium (TV/MG) assay for detection of T. vaginalis DNA compared with patient infection status (PIS) defined by a combination of commercially available NAATs and culture using urogenital specimens. A total of 2,064 subjects (984 men and 1,080 women, 940 [45.5%] symptomatic, 1,124 [54.5%] asymptomatic) were evaluable. In women, sensitivity ranged from 99.4% (95% confidence interval [CI] 96.8 to 99.9%) using vaginal samples to 94.7% (95% CI 90.2 to 97.2%) in PreservCyt samples. Specificity ranged from 98.9 to 96.8% (95% CI 95.4 to 97.8%). In men, the cobas TV/MG assay was 100% sensitive for the detection of T. vaginalis in both male urine samples and meatal swabs, with specificity of 98.4% in urine samples and 92.5% in meatal swabs. The cobas TV/MG is a suitable diagnostic test for the detection of T. vaginalis, which could support public health efforts toward infection control and complement existing STI programs.