Janet N. Arno

Does Linezolid Cause Lactic Acidosis by Inhibiting Mitochondrial Protein Synthesis

Linezolid, an oxazolidinone antibiotic, inhibits bacterial protein synthesis by binding to 23S ribosomal RNA (rRNA). We studied 3 patients who experienced lactic acidosis while receiving linezolid therapy. The toxicity may have been caused by linezolid binding to mitochondrial 16S rRNA. Genetic polymorphisms may have contributed to the toxicity in 2 patients.

Men with broken condoms: Who and why?

Objectives: To identify (1) the prevalence of condom breakage, and demographic and sexuality-related differences among young men who have sex with women reporting and not reporting this event; (2) condom-specific behaviours associated with breakage. Methods: Young men (n = 278) attending a clinic for treatment of sexually transmitted infections (STIs) responded to an anonymous questionnaire aided by a CD recording of the questions. The samples were screened to include only men who had used a condom during penile–vaginal sex at least three times in the past 3 months. Condom-specific behaviours (including breakage) were assessed using these last three acts of condom use as the recall period. Correlates achieving bivariate significance were subjected to multivariate analysis. Results: Nearly one third (31.3%) of the men reported recent breakage. The breakage rate was 15%. Three correlates significantly distinguished between men who did and did not report breakage. Men who had past STIs were more likely to report breakage (adjusted odds ratio (AOR) 2.08), as were men who also reported condom slippage (AOR 2.72). Less self-efficacy for correct condom use was also significantly associated with breakage (AOR 1.07). Further, three condom-specific behaviours were significantly associated with breakage: allowing condoms to contact sharp objects (AOR 2.6), experiencing problems with the “fit or feel” of condoms (AOR 2.3) and not squeezing air from the receptacle tip (AOR 2.0). Conclusions: Breakage may be common and may occur in a larger context of difficulties with condoms. STI clinics could potentially benefit some men by providing instructions on the correct use of condoms.

Age and clinical immunity to infections with Chlamydia trachomatis.

Background and Objecfives: The prevalence of chlamydial infection decreases with age possibly in part because of increasing immunity. Goal of this Sfudy:To determine whether increased age is an independent predictor of decreased chlamydial infection and whether chlamydia-specific antibody titer and blastogenesis increase with age. Sfudy Design: Data from all patients cultured for Chlamydia frachomafis between January 1984 and August 1989 were examined and multiple logistic regression models were used to identify the independent predictors of culture positivity. Antichlamydial antibody titer and chlamydia-specific blastogenesis were examined for a subset of patients for correlation with age. Results: Young age was found to be predictive of chlamydial infection independent of all factors examined in men and women. Antibody titers had no relation to age (n = 245) whereas the level of blastogenesis correlated only weakly with age (n = 155). Conclusions: Assays of systemic immunity do not reflect the protection from chlamydial infection associated with age.

Serologic responses of infertile women to the 60-kd chlamydial heat shock protein (hsp60)

OBJECTIVE To determine whether women with Chlamydia trachomatis-associated tubal infertility are more likely than other infertile women to have antibodies to a particular region of the 60-kd chlamydial heat shock protein, hsp60. DESIGN Serologic responses to the chlamydial hsp60 were examined in 43 infertile women seropositive for Chlamydia trachomatis, including 21 women with tubal infertility, 13 women with endometriosis, and 9 women with other causes of infertility. Antibody responses were localized to regions of hsp60 using five nonoverlapping recombinant polypeptides. RESULTS Sixteen women with tubal infertility had anti-hsp60 antibodies compared with seven women with endometriosis and two women with other causes of infertility. Antibodies of 11 women with tubal infertility reacted predominantly with a region of hsp60 containing amino acids (201 to 300) compared with 1 women without tubal infertility. In contrast, antibodies that localized to the carboxyl terminus, amino acids (401 to 544), were seen equally in all groups. CONCLUSIONS Among seropositive infertile women, antibodies that localized to amino acids (201 to 300) were immunodominant in those with tubal infertility but not in those with infertility due to other causes.

Changing Sexually Transmitted Infection Screening Protocol Will Result in Improved Case Finding for Trichomonas vaginalis Among High-Risk Female Populations

Background: Trichomonas vaginalis is a sexually transmitted infection, which is largely underestimated because of ineffective screening protocols and lack of public health attention. Methods: Two studies were conducted to assess the frequency of missed diagnosis of T. vaginalis when using current routine practices for T. vaginalis screening in high-risk female populations. The first study compares the rate of positivity detected using wet preparation microscopy to the number of cases found using polymerase chain reaction (PCR) using residual samples from women attending a public health sexually transmitted disease clinic. The second study compares universal to targeted screening of symptomatic women using PCR on vaginal samples from women screened for sexually transmitted disease at a correctional facility. Results: In the first study, a 5-fold increased incidence of T. vaginalis infection was detected when PCR was performed instead of wet mount microscopy in a sample of 222 women screened at a sexually transmitted disease clinic. The second study detected a 5-fold increase in cases among a sample of 471 incarcerated women when universal screening was implemented. Conclusions: Improving detection of T. vaginalis is critical, given that when left untreated, T. vaginalis increases susceptibility to coinfections including human immunodeficiency virus. Changing screening protocols to use improved diagnostic tools and applying universal screening resulted in increased case finding for T. vaginalis among high-risk women. The prevalence of T. vaginalis coupled with its negative impact on health necessitate greater public health attention is needed in order to reduce incidence rates, improve diagnosis, and to better understand this important, yet underestimated, pathogen.

Slips breaks and falls: Condom errors and problems reported by men attending an STD clinic.

Summary The objective was to comprehensively assess the prevalence of condom-use errors and problems among male clients attending a public sexually transmitted disease (STD) clinic. Men (n = 278) attending an STD clinic completed an anonymous questionnaire. Seven errors and six problems were assessed. Summative scores were tested for associations with three key variables. Of 834 condom-protected events: 19% were associated with ‘fit and feel’ problems, 15% involved breakage, 14% involved lost erection, 9% were associated with lost erection while applying condoms, 8% involved slippage during withdrawal and 7% involved slippage during sex. A mean of 6.4 errors/problems were observed. None of these summative variables (total errors, total problems or total of errors and problems) were significantly associated with age, minority status or whether men indicated they had ever been taught how to use condoms. Multiple types of condom-use errors and problems may be highly prevalent among high-risk men attending public STD clinics.

Identification of T Cells that Respond to Serovar-Specific Regions of the Chlamydia trachomatis Major Outer Membrane Protein in Persons with Serovar E Infection

Protection from Chlamydia trachomatis infection is serovar-specific and T cell-dependent; however, the T cell epitopes identified to date have not been serovar-specific. The chlamydial major outer membrane protein (MOMP) contains serovar-specific B cell epitopes in four regions of the molecule whose amino acid sequence varies among serovars, the variable segments (VS). Serovar-specific T cell epitopes were sought by examining proliferation of blood mononuclear cells (PBMC) from Chlamydia-infected patients in response to VS peptides of serovar E MOMP. Serovar E-specific peptides from VS1, VS2, and VS4 stimulated PBMC to a greater extent in serovar E-infected than in non-E-infected subjects. Peptides containing constant regions of MOMP were recognized equally by all infected persons. The observed responses were attributable to T cells. T cell recognition of serovar-specific regions of MOMP is common and may contribute to the serovar-specific protection previously observed.

Correlates of Putting Condoms On After Sex Has Begun and of Removing Them Before Sex Ends: A Study of Men Attending an Urban Public STD Clinic:

This study aimed to identify possible correlates of putting condoms on after sex has begun and taking them off before sex has ended among male patients of an urban, public sexually transmitted disease clinic. Participants responded to a questionnaire and were largely African American men, 18 to 35 years old, who had used a condom during penile-vaginal intercourse at least three times in the past 3 months. In controlled analyses, men who were not highly motivated to use condoms correctly were nearly twice as likely to put a condom on after sex had begun. Men who reported erection loss during sex were about twice as likely to remove condoms before sex ended. Men reporting difficulties with the fit and feel of condoms were 2.5 times more likely to remove condoms early. Identified correlates may be amenable to clinic-based education and counseling augmented by offering a variety of condom brands and sizes to patients.

Identifying likely syphilis transmitters: Implications for control and evaluation

Background/Objectives: Persistence of syphilis in communities may be maintained by relatively small groups of high-risk persons centrally placed among a larger group with low to moderately risky behavior. We sought to determine which control strategies identified particularly high-risk, early-stage syphilis cases considered to have high prevention value. Methods: In 2 cities with recent heterosexual outbreaks, data were abstracted for early syphilis cases from 1997 through 2002. Disease stage and number of sex partners were used to create an index to estimate the relative likelihood and magnitude of future transmission had the case not been treated. We estimated the relative transmission potential for each stage of syphilis (primary = 4.3, secondary = 2.5, and early-latent = 1.0) and multiplied by the number of reported partners to determine a prevention value score. Cases scoring >10 were considered high prevention value. Cases were stratified by the method used to detect the case. Results: Of 1700 female early syphilis cases, 174 (10%) were high value. Cases were identified by private physicians (28% of all female cases and 16% of high-value cases), jails (19% of all, 40% of high-value cases), partner notification (16% of all, 10% of high-value cases), sexually transmitted disease (STD) clinic (9% of all, 13% of high-value cases), and the emergency room (8% of all, 4% of high-value cases). Of 1851 male cases, 228 (12%) were high value. Cases were identified by jails (27% of all male cases and 14% of high-value cases), STD clinic (21% of all, 47% of high-value), private physicians (17% of all, 17% of high-value), partner notification (14% of all, 11% of high-value), and the emergency room (6% of all, 14% of high-value). Conclusions: Private physicians identified the most female cases; however, jail screening identified the most high-prevention-value female cases. Jail screening identified the most male cases; however, the STD clinic (self-referred) identified the most high-prevention-value cases. Partner notification identified relatively few high-value cases.

Neisseria meningitidis ST11 complex isolates associated with nongonococcal urethritis, Indiana, USA, 2015–2016

At a clinic in Indianapolis, Indiana, USA, we observed an increase in Neisseria gonorrhoeae–negative men with suspected gonococcal urethritis who had urethral cultures positive for N. meningitidis. We describe genomes of 2 of these N. meningitidis sequence type 11 complex urethritis isolates. Clinical evidence suggests these isolates may represent an emerging urethrotropic clade.