Factors associated with repeat rectal Neisseria gonorrhoeae and Chlamydia trachomatis screening following inconclusive nucleic acid amplification testing: A potential missed opportunity for screening

Autoři: Cheríe S. Blair aff001;  Omai B. Garner aff002;  Bettina Pedone aff003;  Sam Elias aff003;  W. Scott Comulada aff004;  Raphael J. Landovitz aff001
Působiště autorů: Department of Medicine, Division of Infectious Diseases, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America aff001;  Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America aff002;  Arthur Ashe Student Health and Wellness Center, University of California, Los Angeles, California, United States of America aff003;  Department of Psychiatry and Biobehavioral Services, University of California, Los Angeles, California, United States of America aff004
Vyšlo v časopise: PLoS ONE 14(12)
Kategorie: Research Article
doi: https://doi.org/10.1371/journal.pone.0226413



Given rising incidence of Neisseria gonorrhoeae and Chlamydia trachomatis (GC/CT), development of efficacious screening strategies is critical to interruption of the infection cycle. However, a small proportion of nucleic acid amplification testing (NAAT) results are inconclusive—resulting in delays in diagnosis and treatment. As such, this study seeks to evaluate factors associated with inconclusive rectal GC/CT NAAT.


This is a retrospective chart review of individuals who received an inconclusive rectal GC/CT NAAT result at a single institution from 3/2016-6/2018. Inconclusive GC/CT NAAT was defined as presence of PCR amplification inhibitors using Roche Cobas v2.0 CT/NG assay. Clinical charts were abstracted for age, gender, HIV status, GC/CT (urogenital, rectal, pharyngeal) and syphilis screening results during the study period, clinic type (HIV clinic, university student health center, other), and whether repeat testing occurred within 6 months following an inconclusive result. Logistic regression analysis was used to calculate adjusted and unadjusted odds ratios of factors associated with receipt of repeat testing following an inconclusive rectal GC/CT NAAT result.


During the study period, 6.1% (852/14,015) of rectal GC/CT NAAT were inconclusive for one or both of GC and CT. Among the 413 patients whose inconclusive rectal GC/CT NAAT results that were included in our analysis, 66.6% (275/413) received repeat testing within 6 months, of which 8.7% (24/275) were positive (compared to 5.4% positivity rate of all rectal samples). In multivariable analysis, individuals living with HIV had lower odds of receiving repeat testing following inconclusive rectal GC/CT NAAT compared to HIV uninfected individuals (adj OR 0.25; p = 0.001).


Despite being disproportionately affected by the STI epidemic, individuals living with HIV had 75% lower odds of receiving repeat testing following inconclusive rectal GC/CT NAAT compared to HIV-uninfected individuals, representing potentially missed opportunities for treatment and prevention of ongoing STI transmission.

Klíčová slova:

HIV epidemiology – Chlamydia infection – Nucleic acids – Rectum – Syphilis


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2019 Číslo 12
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