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

Cheríe S Blair,W Scott Comulada,Sam Elias,Omai B Garner,Raphael J Landovitz,Bettina Pedone

doi:10.1371/journal.pone.0226413

Abstract

ObjectiveGiven 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.MethodsThis 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.ResultsDuring 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).ConclusionsDespite 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.

Highlights

Incidence of sexually transmitted infections (STIs) have been steadily increasing in recent years, with the two most prevalent bacterial STIs being Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) [1]
Clinical charts were abstracted for age, gender, HIV status, GC and/or CT (GC/CT) 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
Individuals living with HIV had lower odds of receiving repeat testing following inconclusive rectal GC/CT Nucleic acid amplification tests (NAAT) compared to HIV uninfected individuals

Summary

Introduction

Incidence of sexually transmitted infections (STIs) have been steadily increasing in recent years, with the two most prevalent bacterial STIs being Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) [1]. Nucleic acid amplification tests (NAAT) are commonly used for extragenital screening, as they are more sensitive than culture for detection of both GC and CT [5]. Since inconclusive GC/CT screening can result in diagnosis and treatment delays, understanding factors associated with repeat testing is crucial to the development of effective screening programs and implementation of interventions to reduce incidence. This analysis aims to describe factors associated with repeat testing following inconclusive rectal GC/CT NAAT among individuals who underwent GC/CT screening at a large academic institution in Los Angeles

Methods

Results

Conclusion