Use of viability PCR for detection of live Chlamydia trachomatis in clinical specimens

BackgroundThe current testing approach to diagnose Chlamydia trachomatis (CT) infection relies on nucleic acid amplification tests (NAATs). These tests are highly sensitive, but do not distinguish between active infection and residual bacterial nucleic acid which may remain after resolution of infection, or via cross-contamination. Better methods to assess the viability of CT detected in clinical samples would be useful in determining the relevance of CT detection in a variety of clinical settings. The goal of this study was to test viability PCR (vPCR) as a method to distinguish viable bacteria from non-viable CT.MethodsThe vPCR relies on a propidium monoazide dye (PMAxx), which intercalates into accessible DNA from dead organisms and prevents their detection in a PCR assay for the CT ompA gene. We used digital PCR to quantify absolute genome copy numbers from samples. We validated the vPCR approach using laboratory stocks of CT with known viability. Then, we tested total DNA, viable CT DNA, and culture results from 18 clinical vaginal specimens and 25 rectal clinical specimens, all of which had tested positive by NAAT.ResultsIn laboratory stocks of CT, vPCR using defined ratios of heat-killed to live bacteria tracked closely with expected results. In vaginal clinical specimens, vPCR and total DNA results were correlated, though total DNA genomes outnumbered viable genomes by 2.2–52.6-fold more copies. As expected, vPCR detected more total genomes than culture results. Both vPCR and total DNA correlated with culture results (Spearman correlation R = 0.8425 for total DNA and 0.8056 for vPCR). Ten rectal NAAT positive specimens were negative by total DNA PCR, vPCR, and were negative or inconclusive by culture. Of the 6 rectal specimens that were culture positive, all were total DNA and vPCR positive. vPCR additionally detected viable bacterial DNA in 8 specimens which were NAAT + and culture negative, though levels were very low (mean 1,357 copies/ml)ConclusionsvPCR is a fast and easy method to assess viability in clinical specimens and is more correlated with culture results than total DNA PCR. Inconsistent ratios between total DNA and vPCR results suggest that the amount of dead bacteria varies considerably in clinical specimens. Results from rectal specimens suggest that many NAAT positive specimens do not in fact represent live replicating bacteria, and likely result in significant overuse of unnecessary antibiotics

Sexual behaviour change following HIV testing services: a systematic review and meta-analysis.

INTRODUCTION: Learning one's HIV status through HIV testing services (HTS) is an essential step toward accessing treatment and linking to preventive services for those at high HIV risk. HTS may impact subsequent sexual behaviour, but the degree to which this varies by population or is true in the setting of contemporary HIV prevention activities is largely unknown. As part of the 2019 World Health Organization Consolidated Guidelines on HTS, we undertook a systematic review and meta-analysis to determine the effect of HTS on sexual behaviour. METHODS: We searched nine electronic databases for studies published between July 2010 and December 2019. We included studies that reported on at least one outcome (condom use [defined as the frequency of condom use or condom-protected sex], number of sex partners, HIV incidence, STI incidence/prevalence). We included studies that prospectively assessed outcomes and that fit into one of three categories: (1) those evaluating more versus less-intensive HTS, (2) those of populations receiving HTS versus not and (3) those evaluating outcomes after versus before HTS. We conducted meta-analyses using random-effects models. RESULTS AND DISCUSSION: Of 29 980 studies screened, 76 studies were included. Thirty-eight studies were randomized controlled trials, 36 were cohort studies, one was quasi-experimental and one was a serial cross-sectional study. There was no significant difference in condom use among individuals receiving more-intensive HTS compared to less-intensive HTS (relative risk [RR]=1.03; 95% CI: 0.99 to 1.07). Condom use was significantly higher after receiving HTS compared to before HTS for individuals newly diagnosed with HIV (RR = 1.65; 95% CI: 1.36 to 1.99) and marginally significantly higher for individuals receiving an HIV-negative diagnosis (RR = 1.63; 95% CI: 1.01 to 2.62). Individuals receiving more-intensive HTS reported fewer sex partners at follow-up than those receiving less-intensive HTS, but the finding was not statistically significant (mean difference = -0.28; 95% CI: -3.66, 3.10). CONCLUSIONS: Our findings highlight the importance of using limited resources towards HTS strategies that focus on early HIV diagnosis, treatment and prevention services rather than resources dedicated to supplementing or enhancing HTS with additional counselling or other interventions

AIDS Drug Assistance Program disenrollment is associated with loss of viral suppression beyond differences in homelessness, mental health, and substance use disorders: An evaluation in Washington state 2017-2019.

AIDS Drug Assistance Programs (ADAPs) are state-administered programs that pay for medical care for people living with HIV in the US. Maintaining enrollment in the programs is challenging, and a large proportion of clients in Washington state (WA) fail to recertify and are disenrolled. In this study we sought to quantify the impact of disenrollment from ADAPs on viral suppression. We conducted a retrospective cohort study of the 5238 clients in WA ADAP from 2017 to 2019 and estimated the risk difference (RD) of viral suppression before and after disenrollment. We performed a quantitative bias analysis (QBA) to assess the effect of unmeasured confounders, as the factors that contribute to disenrollment and medication discontinuation may overlap. Of the 1336 ADAP clients who disenrolled ≥1 time, 83% were virally suppressed before disenrollment versus 69% after (RD 12%, 95%CI 9-15%). The RD was highest among clients with dual Medicaid-Medicare insurance (RD 22%, 95%CI 9-35%) and lowest among privately insured individuals (RD 8%, 95%CI 5-12%). The results of the QBA suggest that unmeasured confounders do not negate the overall RD. The ADAP recertification procedures negatively impact the care of clients who struggle to stay in the program; alternative procedures may reduce this impact

A Pharmacist-Led, Same-Day, HIV Pre-Exposure Prophylaxis Initiation Program to Increase PrEP Uptake and Decrease Time to PrEP Initiation

Mississippi has one of the highest rates of HIV in the United States, but has low pre-exposure prophylaxis (PrEP) uptake, particularly among black men who have sex with men (MSM) and women. From November 2018 to May 2019, patients at high risk of HIV who tested negative for HIV at a nonclinical testing center in Jackson, Mississippi, were referred to an on-site clinical pharmacist for same-day PrEP initiation. The pharmacist evaluated patients for medical contraindications to PrEP, but no baseline labs were obtained. The pharmacist provided a PrEP prescription and scheduled a clinical appointment for patients within 6 weeks, at which time they were evaluated by a clinician and completed baseline labs. The pharmacist evaluated 69 patients for PrEP; 57% were MSM, 77% were black, and 65% were uninsured. All patients received a PrEP prescription; 83% received the prescription the same day and 97% received it within 5 days. Fifty-three (77%) of 69 clients filled the prescription; 87% of whom filled it within 1 week. Only 23 (43%) of 53 clients who filled their prescription attended their initial clinical appointment within 6 weeks of obtaining PrEP. There were no differences in PrEP initiation or retention by patient sex/gender. This pilot program suggests that an on-site pharmacist working in a nonclinical testing center in the southern United States can successfully initiate PrEP among predominately low-income black MSM. Future efforts should seek to better integrate laboratory testing into this demedicalized model of PrEP and to improve retention in care

Suboptimal adherence to doxycycline and treatment outcomes among men with non-gonococcal urethritis: A prospective cohort study

OBJECTIVE: Doxycycline, one of two recommended therapies for non-gonococcal urethritis (NGU), consists of a seven-day course of therapy (100mg BID). Since suboptimal adherence may contribute to poor treatment outcomes, we examined the association between self-reported imperfect adherence to doxycycline and clinical and microbiologic failure among men with NGU. METHODS: Men aged ≥16 years with NGU attending a Seattle, WA sexually transmitted diseases clinic were enrolled in a double-blind, parallel-group superiority trial from January 2007 to July 2011. Men were randomized to active doxycycline/placebo azithromycin or placebo doxycycline/active azithromycin. Imperfect adherence was defined as missing ≥1 dose in 7 days. Urine was tested for Chlamydia trachomatis (CT), Mycoplasma genitalium (MG), and Ureaplasma urealyticum-biovar2 (UU-2) using nucleic acid amplification tests. Clinical failure (symptoms and ≥5 PMNs/HPF or discharge) and microbiologic failure (positive tests for CT, MG, and/or UU-2) were determined after 3-weeks. RESULTS: 184 men with NGU were randomized to active doxycycline and provided data on adherence. Baseline prevalence of CT, MG, and UU-2 was 26%, 13%, and 27%, respectively. 28% of men reported imperfect adherence and this was associated with microbiologic failure among men with CT (aRR=9.33; 95% CI=1.00–89.2) and UU-2 (aRR=3.08; 95% CI=1.31–7.26) but not MG. Imperfect adherence was not significantly associated with clinical failure overall or for any specific pathogens, but it was more common among imperfectly adherent men with CT (aRR=2.63; 0.93–7.41, p=0.07). CONCLUSIONS: Adherence may be important for microbiologic cure of select pathogens. Factors other than adherence should be considered for CT-negative men with persistent NGU

Efficacy of standard therapies against Ureaplasma species and persistence among men with non-gonococcal urethritis enrolled in a randomised controlled trial.

OBJECTIVE: U. urealyticum biovar 2 (UU-2) but not U. parvum (UP) has been associated with non-gonococcal urethritis (NGU), but little is known about species-specific responses to standard therapies. We examined species-specific treatment outcomes and followed men with treatment failure for 9 weeks. METHODS: From May 2007-July 2011, men aged ≥16 attending an STD clinic in Seattle, Washington with NGU (urethral discharge or urethral symptoms plus ≥5 PMNs/HPF) were enrolled in a double-blind, randomized trial. Participants received active azithromycin (1g) + placebo doxycycline or active doxycycline (100mg bid × 7d) + placebo azithromycin. Ureaplasmas were detected in culture followed by species-specific PCR. Outcomes were assessed at 3, 6, and 9 weeks. At 3 weeks, men with persistent Ureaplasmas received “reverse therapy” (e.g., active doxycycline if they first received active azithromycin). At 6 weeks, persistently-positive men received moxifloxacin (400mg × 7d). RESULTS: Of 490 men, 107 (22%) and 60 (12%) were infected with UU-2 and UP, respectively, and returned at 3 weeks. Persistent infection was similar for UU-2-infected men initially treated with azithromycin or doxycycline (25% vs. 31%, P=0.53), but differed somewhat for men with UP (45% vs. 24%; P=0.11). At 6 weeks, 57% of UU-2-infected and 63% of UP-infected men who received both drugs had persistent infection. Failure after moxifloxacin occurred in 30% and 36%, respectively. Persistent detection of UU-2 or UP was not associated with signs/symptoms of NGU. CONCLUSION: Persistent infection after treatment with doxycycline, azithromycin, and moxifloxacin was common for UU and UP, but not associated with persistent urethritis