Departments of Medicine and Epidemiology, Division of Infectious Diseases, University of Alabama at Birmingham

SUPPLEMENT ARTICLE Diagnosis and Management of Uncomplicated Chlamydia trachomatis Infections in Adolescents and Adults: of Evidence Reviewed for the 2015 Centers for Disease Control and Prevention Sexually Transmitted Diseases Treatment Guidelines William M. Geisler Departments of Medicine and Epidemiology, Division of Infectious Diseases, University of Alabama at Birmingham In preparation for the 2015 Centers for Disease Control and Prevention (CDC) Sexually Transmitted Diseases (STD) Treatment Guidelines, the CDC convened an advisory group in 2013 to examine recent abstracts and published literature addressing the epidemiology, diagnosis, and management of STDs. This article summarizes the key questions, evidence, and recommendations for the diagnosis and management of uncomplicated Chlamydia trachomatis (CT) infection in adolescents and adults that were considered in development of the 2015 CDC STD Treatment Guidelines. The evidence reviewed primarily focused on CT infection risk factors in women, clinical significance of oropharyngeal CT detection, acceptability and performance of CT testing on self-collected specimens in men, performance of CT point-of-care tests, efficacy of recommended and investigational CT infection treatments, and timing of test of cure following CT infection treatment in pregnant women. Keywords. chlamydia; diagnosis; management; CDC; guidelines. Chlamydia trachomatis (CT) infection is the most frequently reported bacterial sexually transmitted infection in the United States and remains highly prevalent, with >1.4 million cases reported to the Centers for Disease Control and Prevention (CDC) annually [1]. Young age is a strong predictor of CT infection, with the highest CT infection prevalence in persons <25 years of age [1]. Because the majority of CT infections are asymptomatic, detection of infection often relies on screening. The 2010 CDC Sexually Transmitted Diseases (STD) Treatment Guidelines recommends annual Correspondence: William M. Geisler, MD, MPH, University of Alabama at Birmingham, 703 19th St S, 242 Zeigler Research Bldg, Birmingham, AL 35294-0007 (wgeisler@uab.edu). Clinical Infectious Diseases 2015;61(S8):S774 84 The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com. DOI: 10.1093/cid/civ694 CT screening in all sexually active women 25 years of age or younger and also older women with risk factors (eg, those who have a new sex partner or multiple sex partners) [2]. Benefits of CT screening in women have been demonstrated in areas where screening programs have reduced rates of pelvic inflammatory disease (PID) [3, 4], a precursor of infertility, and recent literature suggests a continued decline in PID rates in the United States [5]. The approach to the diagnosis and management of uncomplicated CT infection in adolescents and adults includes (1) CT testing using nucleic acid amplification tests (NAATs); (2) treatment with CDC-recommended therapy to reduce complications and prevent transmission to others; (3) treatment of sexual partners to prevent reinfection of patients and complications in patients and partners; (4) risk-reduction counseling; (5) repeat CT testing a few months following treatment to identify repeat infection; and (6) a test of cure (TOC) S774 CID 2015:61 (Suppl 8) Geisler

in pregnant women at a minimum of 3 weeks following treatment to identify persisting or repeat infection so that repeat treatment can be provided promptly to reduce risk for maternal and neonatal morbidity. Following release of the 2010 CDC STD Treatment Guidelines [2], unanswered questions and topics requiring further study on the epidemiology, diagnosis, and management of uncomplicated CT infection remained. In preparation for the 2015 CDC STD Treatment Guidelines, the CDC convened an advisory group in 2013 to review evidence and make recommendations on the diagnosis and management of CT infections in adolescents and adults. This article summarizes the key questions and evidence related to diagnosis and management of uncomplicated CT infection considered in the development of the guidelines. The review and recommendations focused on key questions with new evidence or those covering topics of higher priority. SUBJECTS AND METHODS A search of the literature from 6 November 2008 through 14 February 2013 was conducted using the PubMed/Medline computerized database of the US National Library of Medicine and was limited to reports involving humans as subjects. The search included the Medical Subject Heading (MeSH) terms Chlamydia Infections and Chlamydia as well as the keywords chlamydia and chlamydial in titles and abstracts (tiab). The search yielded 2800 citations. A second search for the same time period was conducted to identify publications that had not yet been indexed in Medline. The search included the terms chlamydia and chlamydial and was limited to publications in English. To eliminate many of the duplicate citations from the initial search and to focus on the newest articles, the phrase NOT medline[sb] was added to the search statement. This omitted citations that were indexed in Medline that were retrieved with the first search and retrieved those that had not yet been indexed for Medline. This second search yielded 501 citations. Abstracts from national and international STD meetings were also reviewed. In addition, we reviewed selected articles that were previously identified in literature searches performed for the 2006 and 2010 CDC STD Treatment Guidelines [6, 7]. Articles solely discussing Chlamydia species other than CT, lymphogranuloma venereum, or trachoma and those whose study population did not include adolescents or adults were excluded. Citations were then selected and reviewed for key questions that could be addressed with new evidence or were deemed of high priority. Articles were summarized in a table of evidence with respect to study design, methodology, results, and conclusions. The quality of the evidence and discussions with expert consultants were then used to address key questions and to formulate recommendations for the 2015 CDC STD Treatment Guidelines. Below are the key questions addressed at the meeting, the summary of evidence, and recommendations for the guidelines. RESULTS Are There Any Clinical Studies of New Treatment Regimens for CT Infection? There were only 2 published studies since the literature review performed for the 2010 CDC STD Treatment Guidelines [7] that addressed new treatment regimens for CT infection, each evaluating an antibiotic not approved by the US Food and Drug Administration (FDA) at the time of the publication. Ito et al prospectively evaluated sitafloxacin 100 mg twice daily for 7 days for symptomatic nongonococcal urethritis (NGU) in heterosexual men [8]. Of 33 men with CT detected at baseline by polymerase chain reaction (PCR), clinical cure (symptom resolution) and microbiological cure (by urine CT PCR within 35 days of treatment) was reported in 89% and 100%, respectively. It is unclear how many subjects had repeat CT testing at 21 days, whose results could be confounded by a false-positive test result due to residual CT nucleic acids. Sitafloxacin is not currently available in the United States. Geisler et al performed a double-blinded, multicenter randomizedcontrolledtrial(rct)ofwc2031(doxycyclinehyclate delayed-release 200 mg tablet) orally once daily for 7 days vs vibramycin 100 mg (generic doxycycline) orally twice daily for 7 days for treatment of uncomplicated urogenital CT infection in men and nonpregnant women [9]. Of 323 CTinfected evaluable subjects, microbial cure rates at the study day 28 visit by CT transcription-mediated amplification (TMA) (on urine in men and a provider-collected vaginal swab in women) were 95.5% (95% confidence interval [CI], 92.3% 98.8%) for WC2031 vs 95.2% (95% CI, 92.0% 98.4%) for vibramycin, meeting noninferiority criteria. Nausea and vomiting occurred less frequently in subjects treated with WC2031 (13% vs 21% and 8% vs 12%, respectively). WC2031 received FDA approval on 12 April 2013 as Doryx delayed-release 200 mg tablet. Once-daily WC2013 (doxycycline 200 mg) for 7 days demonstrated comparable efficacy and safety to twice-daily generic doxycycline for 7 days for uncomplicated urogenital CT infection [9]. WC2031 could improve CT treatment adherence over twice-daily doxycycline and may be better tolerated. A quinolone, sitafloxacin, demonstrated good efficacy in a small number of CT-infected men with symptomatic NGU [8], but it is not FDA approved nor available in the United States. It was recommended that doxycycline hyclate delayed-release 200 mg tablet (Doryx) by mouth daily for 7 days be added as an alternative Chlamydia Management and CDC Guidelines CID 2015:61 (Suppl 8) S775

therapy for uncomplicated urogenital CT infection in the 2015 CDC STD Treatment Guidelines. What New Data Are Available on the Efficacy of Doxycycline and Azithromycin Regimens for Treatment of Uncomplicated Anogenital CT Infection? Several studies published since the previous literature review [7] have addressed efficacy of azithromycin and/or doxycycline for uncomplicated anogenital CT infection. A longitudinal study of repeated CT infection in a cohort of adolescent females by Batteiger et al used CT PCR on cervical and vaginal swabs, analysis of behavioral data, and CT OmpA genotyping to determine an estimated azithromycin efficacy of 92% in 318 evaluable genital CT infections [10]; the study did not evaluate doxycycline and was not a clinical trial. There were 4 publications addressing rectal CT infection treatment [11 14], none of which were RCTs. Three were retrospective studies of azithromycin or doxycycline for rectal CT infection in asymptomatic men who have sex with men (MSM) that reported estimated efficacy based on repeat rectal CT NAAT [11 13]. Drummond et al reported an estimated azithromycin efficacy of 94% in 85 MSM, although the study was limited by the long interval until repeat CT PCR (45% had repeat testing performed >12 weeks after azithromycin treatment) [11]. Steedman et al reported an estimated azithromycin efficacy of 87% in 68 MSM, but 8 of the 9 MSM with a repeat positive CT PCR postazithromycin reported sexual activity between treatment and repeat testing; in addition, 3 of 9 men with repeat positive CT had their repeat test performed 21 days posttherapy, introducing the possibility of a false-positive CT NAAT [12]. Elgalib et al reported an estimated doxycycline efficacy of 98.8% in 165 MSM, although the study was limited in that the majority of rectal CT infected patients initially evaluated were excluded from the efficacy analysis and there was a long interval until repeat CT NAAT was performed (median 45 days) [13]. The fourth study of rectal CT therapy was a prospective observational study in MSM and women by Hathorn et al in which 42 subjects receiving azithromycin and 40 receiving doxycycline during different study phases had an estimated efficacy, adjusting for possible reinfection, of 79% and 100%, respectively, at 6 weeks posttherapy [14]. The study was limited with a high loss-to-follow-up rate (about 50% of subjects), and almost as many subjects received azithromycin during the doxycycline treatment phase and were excluded from analysis. There were 3 publications addressing treatment of NGU due to CT infection [15 17]. Takahashi et al performed a prospective study of azithromycin for NGU and reported 89% microbiological efficacy by urine PCR in 27 CT-infected subjects (81% efficacy in symptomatic men and 100% in asymptomatic men), but was limited in that all men with a repeat positive CT test had testing performed 14 days after therapy, introducing the possibility of a false-positive NAAT; doxycycline was not studied [15]. There were 2 RCTs of azithromycin- vs doxycyclinecontaining regimens for symptomatic NGU in men that reported contradictory microbiological outcome results based on urine TMA testing [16, 17]. Schwebke et al reported that in a subanalysis of 111 CT-infected men, doxycycline had a significantly higher microbiological TOC than azithromycin (95% vs 77%, P =.01) [16]. In contrast, Manhart et al reported that in a subanalysis of 101 CT-infected men, the microbiological TOC did not significantly differ between doxycycline and azithromycin regimens (90% vs 86%, P =.56)[17]. A key methodological difference between the 2 studies was that the timing of TOC was earlier in the Schwebke et al study than the Manhart et al study (as early as 15 days vs 3 weeks), which could have increased the possibility of a false-positive NAAT. It is uncertain whether timing of CT nucleic acid clearance differs following azithromycin vs doxycycline therapy. The only RCT specifically for urogenital CT identified in this literature review was the Geisler et al RCT of WC2031 (doxycycline hyclate delayed-release 200 mg tablet) vs vibramycin discussed earlier in this review, which reported a microbiological CT TOC by TMA in men and women treated with these regimens of 95.5% vs 95.2%, respectively; azithromycin was not studied [9]. There was a previous double-blinded RCT of azithromycin vs doxycycline for urogenital CT in women by Hillis et al that used PCR (on urine and endocervical specimens) to evaluate microbiological TOC at 4 weeks after treatment initiation in 196 women, 98 in each treatment arm, and they reported that the microbiological TOC collected was not significantly different for azithromycin vs doxycycline (95% vs 96%, respectively) [18]. The only 2 RCTs directly comparing doxycycline vs azithromycin for CT infection since the last literature review [7] were in CT-infected subsets of men with symptomatic NGU and had contradictory results [16, 17]. A previous RCT of azithromycin vs doxycycline for uncomplicated urogenital CT infection in women that used PCR for TOC showed high microbiological cure rates for both azithromycin and doxycycline that were similar [18]. It was thought there was insufficient new evidence on the efficacy of azithromycin and doxycycline regimens for urogenital CT infection to suggest changes to the CDC CT treatment recommendations. Non-RCTs evaluating the efficacy of azithromycin or doxycycline for rectal CT infection had major limitations, but did raise some concern about the efficacy of azithromycin for rectal CT infection. It was recommended that text be added to the 2015 CDC STD Treatment Guidelines that raised the concern about the efficacy of azithromycin for rectal CT infection, but also acknowledged that these studies S776 CID 2015:61 (Suppl 8) Geisler

had limitations and that a RCT for rectal CT infection was needed. What New Data Are Available on the Clinical Manifestations, Natural History, Transmissibility, and Treatment of Oropharyngeal CT Infection? There had been insufficient previous data on whether oropharyngeal (OP) CT infection caused any clinically significant disease, the natural history and transmission risk of OP CT infection, and OP CT infection treatment outcomes with doxycycline or azithromycin. Since the previous literature review [7], there have been several studies in men and/or women screened for CT by OP NAAT, which have reported that persons with OP CT infection detected usually do not have OP symptoms [19 25], and select studies have reported that the OP CT prevalence in persons undergoing screening is low (usually <2%) [24, 25]. However, symptomatic OP CT infection may occur in some persons, as reported in 2 studies. Karlsson et al reported that 2 of 48 (4.2%) persons seen in primary care for evaluation of OP discomfort for >14 days had OP CT detected by NAAT without another identifiable bacterial cause, although OP testing for viruses was not performed [22]. Tipple et al reported that of 41 MSM and women with OP CT detected by TMA performed at a genitourinary medicine clinic, 2 (4.8%) had OP symptoms [25]. There was only 1 study identified in the current literature review that evaluated the natural history of OP CT infection in the interval between initial OP CT screening and returning for treatment (at which time OP CT testing was repeated). Apewokin et al found that 1 of 2 (50%) subjects with OP CT infection identified at previous screening had spontaneous resolution of infection (based on negative repeat OP CT NAAT and culture at the time of treatment) [19]. There was an earlier study by Hamasuna et al that reported 6 of 18 (33.3%) sex workers had spontaneous clearance of OP CT (based on negative repeat OP CT NAAT at the time of treatment) [26].These 2 studies suggest that OP CT infection can spontaneously resolve without treatment, as has been reported for genital CT infections [27], but sample sizes in the 2 studies were too small to more precisely estimate the spontaneous resolution frequency. New evidence from 2 publications supported the notion that OP CT can be transmitted to the genital tract, emphasizing the importance of treating OP CT if detected. Marcus et al reported that of 227 heterosexual men whose only urethral exposure was fellatio in the prior 3 months, 8 (3.5%) had urethral CT detected by urine TMA [28]. Similarly, Bernstein et al reported that of 397 MSM whose only urethral exposure was fellatio in the prior 3 months, 19 (4.8%) had urethral CT detected by urine TMA, and urethral CT positivity was higher in human immunodeficiency virus infected individuals (16% vs 3%) [29]. Both studies enrolled patients from a San Francisco STD clinic among whom condom use was very rare. Three studies were identified that evaluated OP CT infection treatment outcomes with a doxycycline or azithromycin regimen [20,22,30]. Wikström et al reported that all 8 women and 1 heterosexual man treated with a doxycycline regimen (200 mg day 1, then 100 mg daily for 8 days) for OP CT infection had a negative repeat OP CT strand displacement amplification (SDA); the timing of repeat testing was not provided [20]. Karlsson et al reported that 2 subjects (a man and woman) with OP CT infection were evaluated following doxycycline therapy, with 1 subject having a clinical cure and the other subject not having a clinical cure but having a negative repeat OP CT NAAT; the doxycycline regimen and timing of repeat testing were not provided [22]. Ota et al retrospectively evaluated OP treatment outcomes in 88 MSM with OP CT diagnosed at a men s clinic in Toronto who were treated with either azithromycin (n = 46) or doxycycline (n = 42) [30]. Of 70 who returned for TOC by NAAT, 3 (4.3%) had a positive TOC, 2 who had received azithromycin and 1 who had received doxycycline; denominator data for the proportion of these 70 MSM who received each regimen were not provided. The 2 subjects receiving azithromycin with a positive TOC initially had a negative TOC at 2 3weeksfollowed by a positive TOC at 3 4 weeks, suggesting reinfection rather than treatment failure. The single subject receiving doxycycline with a positive TOC had their positive TOC at both the first and second TOC time points, suggesting possible treatment failure. Available evidence suggests that most OP CT infections are asymptomatic and some may resolve spontaneously without treatment. Studies suggest that OP CT is transmissible to genital sites [28, 29], which justifies treating patients who have OP CT detected, irrespective of presence of symptoms. However, because studies have demonstrated that OP CT prevalence is very low with routine OP CT screening, routine OP CT screening is not justified in most clinical settings. Published data on use of azithromycin or doxycycline regimens for OP CT infections are insufficient to recommend one regimen over the other. It was recommended to update the text in the 2015 CDC STD Treatment Guidelines to stress that (1) OP CT infection is mostly asymptomatic and because the OP prevalence is usually low, routine OP CT screening is not recommended; (2) because it may be transmissible, OP CT should be treated if identified, which could limit transmission of OP CT infection to anogenital sites; and (3) because of the uncertainty in the efficacy of treatment regimens for OP CT infection, OP CT should be treated with either the azithromycin or doxycycline regimen recommended for urogenital CT. How Well Does CT NAAT Perform on Self-collected Oropharyngeal, Penile, and Rectal Specimens in Men, and What Is the Acceptability of Self-collecting From These Sites? Self-collection of specimens for CT NAAT can further facilitate CT screening, especially in settings where examinations are Chlamydia Management and CDC Guidelines CID 2015:61 (Suppl 8) S777

less feasible. In women, self-collected vaginal swabs are CDCrecommended specimens for CT screening [2]. Since the previous literature review [7], there have been several studies focusing on self-collected specimens for CT testing in men, including OP, penile, and rectal specimens. Three studies identified evaluated CT detection by TMA on patient-collected vs provider-collected OP swabs [31 33], and 2 studies addressed acceptability of self-collecting OP specimens [33, 34]. Sexton et al reported that 5 of 367 (1.4%) MSM had CT detected from a patient- or provider-collected OP swab, with all 5 MSM with CT-positive OP specimens having CT detected from patient-collected swabs vs only 3 of 5 detected from provider-collected OP swabs [31]. Alexander et al reported that 8 of 265 (3%) MSM had CT detected from a patient- or providercollected OP swab, with 3 OP CT-positive MSM having CT detected from both the patient- and provider-collected swabs whereas the remaining 5 OP CT-positive results were detected by just 1 of the swabs (3 by the provider-collected swabs and 2 by the patient-collected swabs) [32]. Freeman et al reported that in 480 MSM who underwent OP CT testing by TMA on self- vs clinician-collected OP swabs, there was 99.4% agreement in results of the 2 testing methods; OP CT was detected in only 1.3% [33]; from an acceptability survey, they also reported that 92% of subjects were willing to self-collect an OP swab at home, 54% had no preference between self- vs clinician-collected strategy, and the majority agreed or strongly agreed that instructions were easy and the specimen was easy to collect. Feasibility and acceptability of MSM self-sampling for OP and rectal STIs was evaluated by Wayal et al, in which 301 subjects seen at a genitourinary medicine clinic were offered OP and rectal self-sampling options and then were provided with a questionnaire [34]. For up to 274 subjects with complete questionnaire data, feasibility and acceptability of self-sampling with OP gargle and mouth pad was higher than for OP swabs (92% and 96% vs 76%, respectively), and self-sampling with rectal swabs was acceptable to 82%. Despite some discomfort, 76% were willing to use all 4 self-sampling methods, and 84% found home sampling acceptable. Two earlier studies evaluated CT detection by NAAT on self-collected OP rinse compared with a providercollected OP swab [26, 35]: Papp et al evaluated OP CT TMA on mouthwash, oral water rinse, and provider-collected OP swabs in 561 MSM and found that 8 (1.4%) had OP CT detected, with all 8 detected from all 3 specimen types; mouthwash and oral water rinse had a sensitivity of 100% and specificity of 99.7%, and self-collection of mouthwash and OP water rinse specimens were highly acceptable [35]. Hamasuna et al evaluated OP CT PCR on oral wash vs provider-collected OP swab in 18 female sex workers with a recent CT PCR positive OP swab and 48 heterosexual men with a recent CT PCR positive urine sample [26]. In sex workers, 11 of 18 (61%) had CT detected from oral wash vs 8 of 18 (44%) by OP swab. In males, 5 of 48 (10%) had CT detected by oral wash vs 3 of 48 (6%) by OP swab. None of the above 5 studies evaluating CT detection from self-collected OP specimens used a second CT NAAT for confirming the positive CT NAAT reported. Two studies were identified that evaluated CT detection from self-collected penile meatal swabs [36, 37]. Dize et al evaluated CT detection by TMA on a self-collected meatal flocked swab (tip of swab placed at meatal opening) vs urine specimen in 634 men, of which CT was detected from 81 (12.8%) by swab vs 66 (10.4%) by urine; 86 (13.6%) were classified as being CT infected based on both specimens being CT positive or 1 specimen CT positive and confirmed by NAAT with a different TMA target [36]. Cherneskey et al evaluated CT detection by TMA on a self-collected meatal swab(s) (tip of swab inserted into urethra and rotated) vs urine specimen in 511 men who were enrolled into 1 of 2 groups: Group A self-collected a meatal Aptima swab and urine, while group B self-collected a meatal Aptima swab, a meatal flocked swab, and urine [37]. Subjects were classified as being CT infected based on 2 specimens being CT positive or 1 specimen CT positive and confirmed by NAAT with a different TMA target. In group A, 20 of 293 (6.8%) were CT infected, and the Aptima swab detected more CT than urine (18 [90%] vs 17 [85%]) and had a higher sensitivity than urine (90% vs 85%). In group B, 20 of 218 (9.1%) were CT infected, and the Aptima and flocked swab both detected 17 (85%), which was more than urine (16 [80%]); swabs again had a higher sensitivity than urine (85% vs 80%). They also evaluated acceptability and reported that 63% of men preferred urine over meatal swab, but most had no difficulty collecting the swab. Results from these 2 studies were contradictory to results from 2 earlier studies [38, 39]. Moncada et al evaluated CT detection by TMA and SDA from a self-collected meatal Dacron swab collected by 1 of 2 methods (method 1: tip of swab rolled over meatus vs method 2: swab inserted into urethra) vs urine in 882 MSM providing these samples [38]. They found that the sensitivity of the meatal swab ranged from 56% to 61% by SDA and 59% 68% by TMA; CT prevalence by urine was 12.2% and classification of CT infection was based on a positive urine NAAT or 2 positive NAATs on the meatal specimen (1 could be an alternate TMA target). Raherison et al reported similar findings in a subset of 344 men who provided a self-collected glans swab (no details on technique) and urine for CT testing by PCR, with sensitivity on those specimens being 67% vs 89%, respectively [39]. Seven studies were identified that evaluated CT detection from self-collected rectal swabs [31, 32, 38, 40 43], and acceptability of self-collecting a rectal swab was evaluated in 5 studies [34, 40 43]. The Sexton et al study discussed above also evaluated patient- vs provider-collected rectal swabs and found that 35 (12.7%) subjects were classified as having rectal CT infection, with all 35 CT-positive subjects identified by patient-collected S778 CID 2015:61 (Suppl 8) Geisler

rectal swab vs only 32 identified by provider-collected rectal swab [31]. The Alexander et al study discussed above also evaluated patient- vs nurse-collected rectal swabs and found that using as gold standard the routine rectal swab tested by SDA, 35 of 258 (13.6%) had rectal CT infection [32]. Rectal swab CT test results for patient- vs nurse-collected rectal swabs were concordant in 246 of 258 (95.3%) patients; sensitivity for rectal CT was higher for self- vs nurse-collected swabs (91.4% vs 80%), and specificity was high (>98%) for both. Van der Helm et al evaluated CT NAATs (mostly PCR) on self- and provider-collected rectal swabs in 901 women and 1411 MSM [40]. CT detection in provider- vs self-collected swabs was comparable for women (9.4% vs 9.3%) and MSM (10.8% vs 10.5%). Self- and provider-collected swabs were concordant for CT in 98% of women and MSM, and sensitivity was slightly higher for provider- vs self-collected rectal swabs in MSM (92% vs 89%) and women (90% vs 89%). They also reported that the majority of MSM (57%) and women (62%) preferred self-collected rectal swabs, and 97% of subjects would visit the clinic again if self-collected swabs were routine. These 3 studies reported a slightly higher sensitivity for the self-collected rectal swab than the earlier study by Moncada et al that reported a sensitivity of 82% for self-collected rectal swabs tested by TMA [38], and all found comparable NAAT performance on self- vs provider-collected rectal swabs. Two small prospective studies by Dodge et al evaluated CT detection by PCR on self-collected rectal swabs from men offered the swab at a variety of clinic- and field/community-based venues [41, 42]. One study evaluated 75 MSM and found that of the 62 MSM who self-collected a rectal swab and agreed to have CT testing performed, 5 (8%) were CT positive [41]. Similarly, the other study evaluated 75 bisexual men and of 58 men who collected a rectal swab and agreed to testing, and 6 (10.3%) were CT positive [42]. Neither study evaluated a provider-collected swab. Both studies evaluated feasibility; 1 study reported that all subjects providing rectal swabs would agree to have rectal testing in the future and given the option, most would prefer self-collection at home [41], whereas the other study found that subjects collecting swabs reported acceptability and comfort with the process, yet reported privacy as the main concern [42].The Wayal et al study evaluated feasibility and acceptability of MSM self-collecting rectal swabs, and the results were discussed above [34]. Finally, Templeton et al retrospectively evaluated 239 asymptomatic MSM seen at a sexual health men s clinic in Sydney who were offered the option of self-collected rectal swabs for rectal CT testing by NAAT [43]. Of 177 (74%) subjects who self-collected a rectal swab, 6 (3.4%) were CT positive; data on subjects who may have had rectal CT testing on both self- and clinician-collected rectal swabs were not provided. Rectal swabs were self-collected more often in subjects seen for a return (vs first visit), seen by a nurse (vs doctor), and reporting any casual partners (vs none). There is limited evidence that self-collected OP specimens may be suitable alternatives to provider-collected OP swabs for OP CT testing and are acceptable to patients, but more studies are needed on NAAT performance on self-collected OP specimens. There is contradictory evidence on NAAT performance on self-collected meatal swabs, and more studies are needed on NAAT performance on self-collected meatal specimens and patient acceptability of self-collecting meatal specimens. Good evidence is shown that NAATs perform as well on self-collected rectal swabs as provider-collected swabs, and studies support self-collection of rectal swabs is acceptable to patients. It was recommended that consideration should be given to adding in the 2015 CDC STD Treatment Guidelines that a self-collected rectal swab is an alternative to provider-collected rectal swab for CT NAAT, especially when rectal exam is not feasible or not preferred by the patient. Are There New Data on Repeat Chlamydia Screening in Pregnant Women During the Third Trimester of Pregnancy? CT screening is recommended at the first prenatal visit for all pregnant women, and repeat screening during the third trimester is recommended for women aged <25 years or those at increased risk. Since the previous literature review [7], there have been 2 additional studies published that evaluated CT rescreening during the third trimester [44, 45] and another study that evaluated results of 1 or more repeat CT tests following the first prenatal visit CT test [46]. Aggarwal retrospectively evaluated CT prevalence pre- and postpartum in adolescent women with genital specimens tested for CT (test not noted) and found that CT was detected at the prenatal visit in 30 of 211 (14%), at a third trimester rescreening in 6 of 173 (3.5%), and postpartum (about 6 weeks) in 3 of 161 (1.9%) [44]. Of the 6 (20%) women with CT detected at the prenatal visit who returned for a 2-week TOC, all 6 (100%) had a positive CT test (suggesting most likely treatment failure or a false-positive test). Hood et al retrospectively evaluated CT detection by DNA probe on a cervical swab at a first prenatal visit vs retesting at 34 36 weeks of gestation in 181 women 25 years of age [45]. They reported that 6 of 181 (3.3%) were CT positive at the first prenatal visit, and CT detection at rescreening was as follows: Of the 175 CT-negative women at the first prenatal visit, 5 (2.9%) were CT positive at rescreening, while of the 6 CT positive at the first prenatal visit, 1 (16.7%) was CT positive at rescreening (P >.05). Overall, 6 of 181 (3.3%) were CT positive at rescreening; CT positivity was likely underestimated due to use of DNA probe. Blatt et al extracted data from a large US laboratory database to retrospectively evaluate the first prenatal visit CT prevalence and CT retesting results in >1 million pregnant women, most (80%) tested by NAAT (20% by DNA probe) [46]. CT screening occurred at any prenatal visit in 59% and at the first prenatal Chlamydia Management and CDC Guidelines CID 2015:61 (Suppl 8) S779

visit in 37%. CT screening rates were higher in younger women and African Americans. CT prevalence was 3.5% at any visit and 2.7% at the first prenatal visit. Most CT rescreening occurred in women with a positive CT test at their first prenatal visit vs those CT negative at that time (78% rescreened vs 13%). CT was detected at any subsequent repeat screening test in 18% (6% at the last repeat CT test) who were initially CT positive vs 2.2% at any subsequent repeat CT test (1.2% at the last repeat CT test) in those initially CT negative. A subanalysis of women 16 25 years of age with an initial CT negative test who underwent repeat screening during pregnancy revealed that 3.4% had a subsequent positive repeat CT test. CT microbiological TOC was performed in 33% of those CT positive at the first prenatal visit within 6 weeks, and 15% had CT detected at TOC. A major study limitation was that the gestational period at the time of the subsequent repeat CT testing visits was not provided or could not be determined. These 3 studies did not provide information on risk factors for CT detection at rescreening during the third trimester other than 2 of the studies evaluating the association with CT positivity at the first prenatal visit [45, 46]. Two recent publications reported CT positivity rates in the 3.3% 3.5% range on repeat CT screening in pregnant adolescent and young adult women during the third trimester [44, 45],and 2 studies reported higher positivity rates at repeat CT testing later in pregnancy in patients who were CT infected at the first prenatal visit CT screening test, although significance of difference was not reported in 1 study [46] and not significant in the other [45]. The studies did not otherwise provide new information on risks associated with CT positivity identified at repeat testing later in pregnancy. It was thought that there was insufficient new evidence to change the current recommendation for repeat CT screening during the third trimester in women aged <25 years or those at increased risk for CT infection. However, it was suggested to provide text and references in the 2015 CDC STD Treatment Guidelines acknowledging findings from newer studies supporting this retesting recommendation. Are There New Data on Timing of Repeat CT Testing After Treatment Using NAAT for Evaluating Test of Cure? TOC following CT treatment is only routinely recommended for CT-infected pregnant women, and the recommended timing for repeat TOC is 3 4 weeks after completing therapy [2]. However, timing of CT TOC by NAAT is also highly relevant to CT treatment trials. The concern of testing too early following treatment is a false-positive CT NAAT due to detection of residual CT nucleic acids from dead organisms, whereas the concern for delaying testing too long is the risk for repeat CT exposure from a CT-infected partner leading to a positive TOC that may represent reinfection rather than treatment failure. Since the previous literature review [7], 2 studies have been published that evaluated timing of CT nucleic acid clearance after treatment [47, 48]. Renault et al used TMA to evaluate CT ribosomal RNA (rrna) clearance from vaginal swabs selfcollected by up to 61 urogenital NAAT CT-positive adolescent women at 4 time points within 2 weeks of single-dose azithromycin 1 g treatment [47]. CT rrna was detected in 54 of 61 (88%) at day 3, 33 of 61 (54%) at day 7, 21 of 61 (34%) at day 10, and 13 of 61 (21%) at day 14. Multilinear regression analysis predicted full CT rrna clearance at day 17, but no testing was performed beyond 14 days. Dukers-Muijrers et al used PCR and TMA to evaluate CT DNA and rrna clearance, respectively, from cervicovaginal and anogenital specimens from 46 CT-infected women and anogenital specimens from 6 CT-infected MSM at 6 time points between 23 51 days after azithromycin [48]. They reported that CT rrna or DNA was detected at posttreatment day 23, 26, 30, 37, 44, and 51 in 14%, 20%, 16%, 17%, 22%, and 24%, respectively; overall, 25 of 59 (42%) baseline infections were detected again at least once between 23 and 51 days posttreatment. There was substantial inter- and intraindividual variation over time and by NAAT, with most CT nucleic acids being detected intermittently (ie, at different time points often with interval-negative CT NAAT results), which could represent repeat infections or repeat CT nucleic acid exposure and, less likely, persisting CT infection. Four earlier studies also evaluated CT nucleic acid clearance after CT treatment [49 52]. Morré et al used PCR andreal-timenucleicacidsequence based amplification to evaluate clearance of CT DNA and rrna, respectively, from cervical brushes (and urine in a subset) collected from 25 genital CT enzyme immunoassay positive women weekly starting from initiation of a 7-day course of doxycycline [49]. CT rrna was detected in 2 of 25 subjects and DNA in 21 of 25 at 1 week after doxycycline initiation; no subjects had rrna detected vs 6 of 21 being DNA positive at week 2; 5 of 20 DNA were positive at week 3, and 1 of 6 DNA positive at week 4. Workowski et al used PCR to evaluate clearance of CT DNA from anogenital swabs, collected from 20 women with anogenital CT infection, for 5 time points up to 20 weeks starting from the initiation of doxycycline [50]. They found that 10 of 20 subjects had CT DNA detected at 1 week (ie, end of doxycycline treatment), 3 of 20 DNA at 2 weeks, and no DNA detected starting from the next scheduled visit at 4 weeks. Gaydos et al used PCR and ligase chain reaction (LCR) to evaluate clearance of CT DNA from urine collected from 33 cervical CT-infected women for approximately every other day following completion of treatment with azithromycin 1 g (n = 26) or a doxycycline 7-day course (n = 7) [51]. CT DNA was detected as follows: (1) at 1 3 days posttreatment PCR positive 40%, LCR positive 73.3%; (2) 4 6 days posttreatment PCR positive 21%, LCR positive 37%; (3) 7 9 days posttreatment PCR positive 25%, LCRpositive13%;(4) 10 12daysposttreatment PCR positive 0%, S780 CID 2015:61 (Suppl 8) Geisler

LCR positive 10%; (5) 13 15 days posttreatment PCR positive 14%, LCR positive 0%; and (6) >16 days posttreatment no PCR- or LCR-positive specimens. Bianchi et al used PCR and TMA to evaluate clearance of CT DNA and rrna, respectively, from urine collected daily for 1 week after azithromycin treatment in 14 CT-infected females and 5 CT-infected males and also performed NAAT testing in a subset of 5 subjects who returned at day 14 [52]. They found that all females were CT DNA and rrna negative by day 6, whereas in men there were 1 of 5 DNA positive and none rrna positive by day 7; none of the 5 patients tested at day 14 had CT DNA detected. Abstinence was addressed in only 3 of the published studies on timing of repeat CT testing after treatment [47, 48, 51]. There is considerable heterogeneity in the limited number of studies evaluating CT nucleic acid clearance posttherapy, in terms of sex, antibiotic treatment, timing of repeat CT NAAT, evaluation of DNA or RNA, specimen type, and whether abstinence was addressed. Such differences make it challenging to determine a precise estimate of CT nucleic acid clearance that would be useful for CDC recommendations. Considering that some studies reported that DNA or RNA could be detected in a significant proportion of subjects at 2 3 weeks after treatment, it seemed reasonable to continue the recommendation for the upcoming 2015 CDC STD Treatment Guidelines that TOC be performed in CT-infected pregnant women 3 4 weeks after completing therapy. Are New Data Available on CT Risk Factors in Women >25 Years of Age That Could Help Guide CT Screening Recommendations in This Population? For women >25 years of age, the CDC recommends CT screening in those with CT risk factors (eg, those who have a new sexual partner or multiple partners) [2]. Since the previous literature review [7], 2 studies have been published that evaluated CT risk factors in older women [53, 54], both analyzing data from the National Health and Nutrition Examination Survey (NHANES), which included a nationally representative sample of persons who had CT NAAT (either LCR or SDA) performed on urine. Torrone et al retrospectively evaluated predictors of higher-weighted CT prevalence estimates in 3875 women 26 39 years of age who participated in NHANES cycles 1999 2010 [53]. They reported a CT prevalence of 1.2% in this age group, and it significantly varied by race (highest in African Americans at 2.5%), marital status (highest in women widowed/divorced/separated at 2.7% vs never married at 1.9% vs married/living with a partner at 0.8%), education (highest in those with less than a high school education or equivalent at 2%), sexual partner number (highest in those with 2 partners in the last 12 months at 2.9%), and hormone use (highest in women who never used oral contraceptives or Depo-Provera at 3.4%). Beydoun et al retrospectively evaluated predictors of higher weighted CT prevalence estimates in men and women 20 39 years of age who participated in NHANES cycles 1999 2006 [54]. They reported that the CT prevalence was 1.3% in 2311 women aged 25 39 years and significantly differed by race (highest in African Americans at 3.1%), marital status (highest in never married at 3% vs ever married at 1.1% vs cohabiting at 0.7%), and education (highest in those with less than a high school education at 3%). Because of the low CT prevalence in older women evaluated in both studies, there may have been insufficient power to detect some associations of patient characteristics with higher CT prevalence. Howard et al previously presented findings from a cross-sectional study of CT predictors in women 26 30 years of age at the 2008 National STD Prevention Conference [55]. Among 1243 sexually active women in this age group presenting to family planning clinics in California, urogenital CT was detected in 39 (3.1%). The following were reported as CT infection predictors: The patient indicated that their sexual partner(s) possibly had concurrent partners (ie, having sex with another partner[s] while still in the relationship with the patient) in the past 3 or 12 months; havingmorethan1or2sexualpartnersinthepast3or12 months; having a bacterial vaginosis diagnosis, and having a new sexual partner in the past 3 months. CT infection was negatively associated with being married and being in a stable relationship (married, engaged, or living with a partner). The association of bacterial vaginosis with CT infection has been previously reported [56, 57]. In summary, there remains limited literature published on predictors of CT infection in women >25 years. There were 2 new studies published that evaluated CT predictors in a nationally representative sample of older women [53, 54] and a study presented at a national meeting that evaluated CT predictors in older women seen in family planning clinics [55]. Because of the low CT prevalence in the populations studied, findings from these studies should be considered as preliminary and ideally should be verified in other cohorts before adding them as CT predictors in older women in the CDC STD Treatment Guidelines, although expert consultants did feel it was appropriate to add the CT predictor of patients indicating their partner may have a concurrent partner, based on plausibility that it was likely a CT infection risk factor. Are New Data Available on the Performance and Costeffectiveness of CT POC Tests Compared With CT NAAT? A CT POC test could provide the opportunity to treat CTinfected patients within minutes to an hour of undergoing CT testing and before leaving the testing site, thereby ensuring that Chlamydia Management and CDC Guidelines CID 2015:61 (Suppl 8) S781

CT-infected patients get treated. Such prompt treatment could limit CT complications and CT transmission to others. However, CT POC tests have been limited by lower sensitivity than NAAT. Since the previous literature review [7], there have been 6 studies published on performance of commercially available CT POC tests [58 63]. Bandea et al evaluated the performance of the Biostar Chlamydia OIA (optical immunoassay) POC test on cervical swabs compared with NAAT (TMA and LCR) and culture and found that with CT NAAT (concordant LCR and TMA) as the reference standard, OIA had a sensitivity of 59.4% and specificity of 98.4% [58]. Sabidó et al evaluated the performance of the Chlamydia test card POC test on cervical swabs compared with CT PCR and found that with PCR as the reference standard, the Chlamydia test card had a sensitivity of 62.9% and specificity of 99.6% [59]. Van Dommelen et al evaluated the performance of 3 CT POC tests on vaginal swabs compared with CT PCR and found that with CT PCR as the reference standard, the sensitivities of the Handilab-C test, Biorapid CHLA- MYDIA Ag test, and QuickVue Chlamydia test were 12%, 17%, and 27%, respectively, whereas the specificities were 92%, 93.5%, and 99.7%, respectively [60]. Van der Helm et al evaluated the performance of the Chlamydia Rapid Test on vaginal swabs compared with CT TMA and found that with TMA as the reference standard, the Chlamydia Rapid Test had a sensitivity of 41.2% and specificity of 96.4%; they further stratified sensitivity by CT load and found that the sensitivity of the Chlamydia Rapid Test was 12.5% with a low CT load and 73.5% with a high CT load [61]. Nadala et al evaluated the performance of the Chlamydia RapidTestonurineinmencomparedwithCTPCRand found that with PCR as the reference standard, the Chlamydia Rapid Test had a sensitivity of 82.6% and specificity of 98.3% [62]; however, women were not studied, and some authors were affiliated with the Chlamydia Rapid Test manufacturer. Hislop et al performed a systematic review through November 2008 of the performance and cost-effectiveness of the Chlamydia Rapid Test vs other CT POC tests using CT PCR as the reference standard [63]. Based on 13 studies reviewed, pooled performance estimates for the Chlamydia Rapid Test were sensitivity of 80% on vaginal swabs and 77% on urine, with a specificity of 99% for both specimen types. A comparator POC CT test, the Clearview Chlamydia test, had lower performance, with a sensitivity of 52% on genital swabs combined (64% cervical only) and specificity of 97% on genital swabs. Both the Chlamydia Rapid Test and the Clearview Chlamydia test were more costly than NAAT from a health service perspective. Since the previous literature review [7], 4 studies have been published on the performance of investigational CT POC tests [64 67]. Hesse et al evaluated the performance of 4 novel CT POC prototypes in succession, each modified based on communication with the manufacturer, on vaginal and cervical swabs compared with SDA [64]. The finalctpocprototypeimproved earlier problems but still had difficulties with readability of test results. Due to the small sample size, earlier prototypes were combined (A B), as were later prototypes (C D) for performance evaluation. With SDA as the reference standard, A B prototypes had a sensitivity of 38% for both samples and specificity of 77% for cervical and 64% for vaginal specimens, whereas C D prototypes had a sensitivity of 80% for both samples and specificity of 37% for cervical and 25% for vaginal specimens (due to a high percentage of indeterminate and falsepositive results). Huang et al evaluated the performance and modeled the cost-effectiveness of a novel CT POC test on cervical, vaginal, and urine specimens in women compared with TMA and found that the sensitivity and specificity of the novel POC CT test were 92.9% and 98.5%, respectively [65]. One-way sensitivity analyses indicated that the CT POC test would be favorable over NAAT if sensitivity were >87.1% and test cost <$41.52. The mean incremental cost-effectiveness ratio indicated that the POC strategy would save $28 in total and avert 14 PID cases. Dean et al evaluated the performance of a novel microfluidic multiplex PCR POC test on cervical swabs compared with the Roche Amplicor NAAT (PCR) and found that the sensitivity and specificity for the multiplex assay was 91.5% and 100% vs 62.4% and 95.9% for NAAT; discordant results between the multiplex assay and NAAT were evaluated using microfluidic Sanger sequencing [66]. Pearce et al evaluated the performance of a novel CT POC test using an electrochemical detection method on 306 samples previously pretyped as either CT positive (n = 107) or CT negative (n = 199) by TMA or PCR and found that the sensitivity and specificity for the novel POC test were 98.1% and 98.0%, respectively [67]. In summary, studies continue to report unacceptably low sensitivities of commercial CT POC tests in women, and they will not be recommended as CT screening tests in the upcoming 2015 CDC STD Treatment Guidelines. Recent studies reported good performance of novel investigational CT POC tests that appear promising [65 67]. Notes Financial support. The author receives grant support from the Alabama North Carolina STD/HIV Training Prevention Center (grant number 5U62PS003292-03) from the Centers for Disease Control and Prevention (CDC). Supplement sponsorship. This article appears as part of the supplement Evidence Papers for the CDC Sexually Transmitted Diseases Treatment Guidelines, sponsored by the Centers for Disease Control and Prevention. Potential conflicts of interest. Author certifies no potential conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed. S782 CID 2015:61 (Suppl 8) Geisler