PubMed Health⌕ Search

Biomedical subjects

T C Quinn

Publications and source records attributed to T C Quinn.

At least 19 recordsLinked to original sources

Features of Chlamydia trachomatis and Neisseria gonorrhoeae infection in male Army recruits.

Non-health care-seeking male United States Army recruits were tested for Chlamydia trachomatis (n=2245) and Neisseria gonorrhoeae (n=884), using a urine ligase chain reaction test to determine prevalence and potential risk factors for infection. The prevalence of chlamydial infection was 5.3%. Black race, a new sex partner, a history of trichomonas, and the presence of symptoms were associated with chlamydial infection. The prevalence of N. gonorrhoeae infection was 0.6%. Only a reported history of or positive test for C. trachomatis was associated with gonorrheal infection. Of those testing positive for chlamydia, 14% reported symptoms versus 40% of those with gonorrhea. Younger age was not a predictor of either infection, as has been shown for women. A substantial number of male army recruits are infected with C. trachomatis, but few are infected with N. gonorrhoeae. Screening on the basis of symptoms alone would miss the majority of both infections.

Adult↗

Evaluation of use of a single intravaginal swab to detect multiple sexually transmitted infections in active-duty military women.

The accuracy and suitability of use of a single intravaginal swab (SIS) for polymerase chain reaction detection of Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis, and human papillomavirus infection was assessed in a cross-sectional study of 841 active-duty military women. The SIS, compared with standard diagnostic tests, allowed detection of more gonorrhea, more chlamydial infection, and more trichomoniasis. Sensitivity and specificity of SIS detection compared with adjudicated true-positive diagnoses were 95.8% and 97.8%, respectively, for gonorrhea, 94.6% and 99.3% for chlamydial infection, and 92.2% and 98.2% for trichomonal infection. Results with SISs were comparable to those with cervical swabs tested for human papillomavirus. Assay of clinician-collected and self-collected SISs yielded prevalences similar to those of standard diagnostic tests for all sexually transmitted infections. Therefore, the use of SISs is acceptable for the simultaneous diagnosis of multiple sexually transmitted infections and has potential for use as a self-administered diagnostic tool with widespread applicability among women.

Administration, Intravaginal↗

Chronic inflammation with increased human immunodeficiency virus (HIV) RNA expression in the vaginal epithelium of HIV-infected Thai women.

Thai residents have a greater risk of heterosexual transmission of human immunodeficiency virus (HIV) than do US residents. To analyze host factors associated with heterosexual transmission, vaginal epithelial biopsies from HIV-seropositive Thai and US women were evaluated for tissue virus load and histologic makeup. In all, 84% of Thai and 14% of US women exhibited a chronic inflammatory T cell infiltrate in the vaginal epithelium. In Thai tissue, the infiltrate was associated with elevated levels of HIV RNA in the epidermis. Uninfected Thai women also had vaginal epithelial inflammation. Inflammation did not correlate with sexually transmitted diseases or HIV disease stage. The higher rates and increased risk of heterosexual transmission in Thailand may be due to chronic inflammation at the site where the virus is transmitted, which leads to the accumulation of activated T cells. Such cells might act as targets for initial viral infection and subsequently as reservoirs that support efficient transmission.

Adult↗

HIV-1 drug resistance profiles in children and adults with viral load of <50 copies/ml receiving combination therapy.

CONTEXT: The continued release of human immunodeficiency virus type 1 (HIV-1) into plasma at very low levels during highly active antiretroviral therapy (HAART) can be detected using specialized techniques, but the nature and significance of this low-level viremia, especially as related to acquisition of drug resistance mutations, are unclear. OBJECTIVE: To determine genetic resistance profiles of low-level plasma HIV-1 in patients with prolonged viral suppression (<50 copies/mL of plasma HIV-1 RNA) while receiving HAART. DESIGN AND SETTING: Cross-sectional study conducted at a US academic hospital from November 1999 to February 2001 using a novel method for amplification of low levels of viral genomes in plasma. PATIENTS: Eighteen HIV-1-infected patients (7 children and 11 adults), enrolled in a longitudinal study of HIV-1 reservoirs, who had suppression of viral replication while receiving protease inhibitor-containing combination therapy. Two patients (1 adult and 1 child) with less optimal suppression of viral replication were included to assess virus predominating when plasma HIV-1 RNA levels are low but detectable (<1000 copies/mL). Follow-up analyses were conducted in 3 patients. MAIN OUTCOME MEASURE: Detection of drug resistance mutations in clones amplified from low-level plasma virus. RESULTS: Viral sequences were amplified from 8 of the 18 patients with simultaneous plasma HIV-1 measurements of less than 50 copies/mL and from 2 patients with 231 and 50 copies/mL. Clones from 3 treatment-naive patients with less than 50 copies/mL of plasma HIV-1 RNA showed continued release, for as long as 42 months, of wild-type drug-sensitive virus. The 7 patients with prior nonsuppressive therapy, with viral loads below 50 copies/mL and during "blips" to 231 and 64 copies/mL, had only resistance mutations consistent with pre-HAART therapy (although reverse transcriptase inhibitor mutations may have continued to occur). New HAART-related mutations were seen in a control patient with prior viral load levels of about 400 to 1000 copies/mL. For phylogenetic analysis, sequences were available for both resting CD4(+) T cells and plasma HIV for 7 of 10 patients and showed patient-specific clustering of sequences and a close relationship between virus in the plasma and the latent reservoir. CONCLUSIONS: Based on the samples that could be amplified, low-level viremia in children and adults receiving HAART with prolonged suppression of viremia to less than 50 copies/mL of HIV-1 RNA may result primarily from archival, pre-HAART virus, reflecting earlier treatment conditions, and does not appear to require development of new, HAART-selected mutations reflecting partial resistance to therapy. Low-level viremia below 50 copies/mL may represent less of a concern regarding impending drug failure of current HAART regimens. However, the archival drug-resistant virus may be relevant regarding future treatment strategies.

Adult↗

Probability of HIV-1 transmission per coital act in monogamous, heterosexual, HIV-1-discordant couples in Rakai, Uganda.

BACKGROUND: The probability of HIV-1 transmission per coital act in representative African populations is unknown. We aimed to calculate this probability overall, and to estimate how it is affected by various factors thought to influence infectivity. METHODS: 174 monogamous couples, in which one partner was HIV-1 positive, were retrospectively identified from a population cohort in Rakai, Uganda. Frequency of intercourse and reliability of reporting within couples was assessed prospectively. HIV-1 seroconversion was determined in the uninfected partners, and HIV-1 viral load was measured in the infected partners. Adjusted rate ratios of transmission per coital act were estimated by Poisson regression. Probabilities of transmission per act were estimated by log-log binomial regression for quartiles of age and HIV-1 viral load, and for symptoms or diagnoses of sexually transmitted diseases (STDs) in the HIV-1-infected partners. RESULTS: The mean frequency of intercourse was 8.9 per month, which declined with age and HIV-1 viral load. Members of couples reported similar frequencies of intercourse. The overall unadjusted probability of HIV-1 transmission per coital act was 0.0011 (95% CI 0.0008-0.0015). Transmission probabilities increased from 0.0001 per act at viral loads of less than 1700 copies/mL to 0.0023 per act at 38 500 copies/mL or more (p=0.002), and were 0.0041 with genital ulceration versus 0.0011 without (p=0.02). Transmission probabilities per act did not differ significantly by HIV-1 subtypes A and D, sex, STDs, or symptoms of discharge or dysuria in the HIV-1-positive partner. INTERPRETATION: Higher viral load and genital ulceration are the main determinants of HIV-1 transmission per coital act in this Ugandan population.

Adolescent↗

Initial plasma HIV-1 RNA levels and progression to AIDS in women and men.

BACKGROUND: It is unclear whether there are differences between men and women with human immunodeficiency virus type 1 (HIV-1) infection in the plasma level of viral RNA (the viral load). In men, the initial viral load after seroconversion predicts the likelihood of progression to the acquired immunodeficiency syndrome (AIDS), but the relation between the two has not been assessed in women. Currently, the guidelines for initiating antiretroviral therapy are applied uniformly to women and men. METHODS: From 1988 through 1998, the viral load and the CD4+ lymphocyte count were measured approximately every six months in 156 male and 46 female injection-drug users who were followed prospectively after HIV-1 seroconversion. RESULTS: The median initial viral load was 50,766 copies of HIV-1 RNA per milliliter in the men but only 15,103 copies per milliliter in the women (P<0.001). The median initial CD4+ count did not differ significantly according to sex (659 and 672 cells per cubic millimeter, respectively). HIV-1 infection progressed to AIDS in 29 men and 15 women, and the risk of progression did not differ significantly according to sex. For each increase of 1 log in the viral load (on a base 10 scale), the hazard ratio for progression to AIDS was 1.55 (95 percent confidence interval, 0.97 to 2.47) among the men and 1.43 (95 percent confidence interval, 0.76 to 2.69) among the women. The median initial viral load was 77,822 HIV-1 RNA copies per milliliter in the men in whom AIDS developed and 40,634 copies per milliliter in the men in whom it did not; the corresponding values in the women were 17,149 and 12,043 copies per milliliter. Given the recommendation that treatment should be initiated when the viral load reaches 20,000 copies per milliliter, 74 percent of the men but only 37 percent of the women in our study would have been eligible for therapy at the first visit after seroconversion (P<0.001). CONCLUSIONS: Although the initial level of HIV-1 RNA was lower in women than in men, the rates of progression to AIDS were similar. Treatment guidelines that are based on the viral load, rather than the CD4+ lymphocyte count, will lead to differences in eligibility for antiretroviral treatment according to sex.

Acquired Immunodeficiency Syndrome↗

Predominance of HIV type 1 subtype G among commercial sex workers from Kinshasa, Democratic Republic of Congo.

We have investigated the genetic diversity and potential mosaic genomes of HIV-1 during the early part of the HIV-1 epidemic among commercial sex workers (CSWs) in Kinshasa, Democratic Republic of Congo (formerly Zaire). Serologic analysis revealed that 27 (28.7%) of the 94 specimens were seropositive by both peptide and whole-virus lysate EIAs and that 24 were positive by molecular screening assays, using generic primers that can detect all known groups of HIV-1. Phylogenetic analyses of the gag(p24), C2V3, and gp41 regions of these 24 specimens showed that all were group M; none of them had any evidence of group O, N, or SIVcpz-like sequences. On the basis of env sequence analysis, the 24 group M specimens were classified as subtypes G (37.5%), A (21%), F1 (12.5%), CRF01_AE (8%), D (4%), and H (4%); 3 (12.5%) were unclassifiable (U). Similar analysis of the gag(p24) region revealed that the majority of infections were subtype A; however, one-third of the specimens were subtype G. Parallel analysis of gag(p24) and env regions revealed discordant subtypes in many specimens that may reflect possible dual and/or recombinant viruses. These data suggest a predominance of subtype G (both pure G and recombinant CRF02_AG) during the early part of the epidemic in Kinshasa. Infections with group N or SIVcpz-like viruses were not present among these CSWs in Kinshasa.

Democratic Republic of the Congo↗

Prolonged measles virus shedding in human immunodeficiency virus-infected children, detected by reverse transcriptase-polymerase chain reaction.

A reverse transcriptase-polymerase chain reaction assay was used to detect measles virus RNA in peripheral blood mononuclear cells, urine, and nasopharyngeal specimens from Zambian children during hospitalization and approximately 1-2 months after discharge. Of 47 children, 29 (61.7%) had prolonged measles virus shedding, as defined by detection of measles virus RNA in > or =1 specimen obtained 30-61 days after rash onset. Ten (90.9%) of 11 human immunodeficiency virus (HIV)-infected children had prolonged measles virus shedding, compared with 19 (52.8%) of 36 HIV-uninfected children (P=.02). Prolonged measles virus shedding did not correlate with levels of measles virus-specific antibody. HIV-infected children with measles may have a prolonged infectious period that potentially enhances measles virus transmission and hinders measles control.

Adolescent↗

Determinants of trachoma endemicity using Chlamydia trachomatis ompA DNA sequencing.

A six-year prospective study of Chlamydia trachomatis infection and ocular disease in Tanzanian village children was conducted to identify the determinants of trachoma endemicity using sequencing of ompA. Overall, 749 conjunctival samples were obtained, with 176 children sampled in both 1989 and 1995. 31.1% (233/749) were positive by PCR-enzyme immunoassay, and 76% (176/233) of the positives were sequenced in variable domains (VD) 1 to 4 (22 children in both 1989 and 1995). Twenty-six ompA genotypes of serovar A, and 19 of B/Ba were identified, and only 20% of genotypes identified in 1995 matched those found in 1989. In particular, B/Ba genotypes exhibited a 15-base region in VD 2 with increased nucleotide substitution, and these types were associated with age and water availability. Homotypic infection and infection with multiple genotypes and high chlamydial load did predict subsequent severe trachoma (odds ratio (OR) = 10.14, 95% confidence interval (CI): 1.71, 60.23; OR = 6.40, 95% CI: 0.75, 54.41; OR = 6.74, 95% CI: 0.82, 55.38, respectively). And, multitypic infection was clustered with residence of village and associated with familial cattle ownership. In conclusion, high ompA polymorphism and the inability of some hosts to clear infection with the same ompA genotype suggest two distinct but converging mechanisms of endemic severe trachoma.

Amino Acid Sequence↗

Unsuspected gonorrhea and chlamydia in patients of an urban adult emergency department: a critical population for STD control intervention.

BACKGROUND: Urban emergency departments (EDs) providing services to patients at high risk for sexually transmitted infection may be logical sites for intervention. GOAL: To determine the prevalence of gonorrhea (GC) and chlamydia (CT) in an adult ED patient population, and to assess risk factors for infection. STUDY DESIGN: Cross-sectional study of patients aged 18 to 44 in an urban ED, seeking care of any medical nature. Main outcome was positive for GC or CT by urine ligase chain reaction assay. RESULTS: Test results for GC and/or CT were positive in 13.6% of 434 18 to 31 year-olds and in 1.8% of 221 32 to 44 year-olds. Of 63 infected individuals identified by the study, 15 (23.8%) were treated at the ED visit. Age < or =31 detected 88% of infections. Among 18- to 31-year-old patients, predictive risk factors by multivariate analysis included age <25, >1 sex partner in the past 90 days, and a history of sexually transmitted disease. CONCLUSION: This study identified a high prevalence of GC and CT in patients seeking ED services. Many of these infections were clinically unsuspected. These data demonstrate that the ED is a high-risk setting and may be an appropriate site for routine GC and CT screening in 18- to 31-year-old patients.

Adolescent↗

Chlamydia, gonorrhea, and HIV-1 prevalence among five populations of women in the Czech and Slovak Republics.

BACKGROUND: Five populations at risk for sexually transmitted diseases (STDs) in the Czech and Slovak Republics were sampled. GOAL: To estimate prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, and HIV-1 infections. STUDY DESIGN: Urine specimens were collected serially from women at a Prague prenatal clinic (n = 134), a Prague dermatovenerealogy clinic (n = 91), sex workers from northern and central Bohemia (n = 35), students from a northern Bohemian school (n = 217), and Gypsies from Jarovnice, Slovakia (n = 128). These specimens were tested for chlamydia and gonorrhea using a ligase chain reaction pooling algorithm, and for HIV using an enzyme immunoassay confirmed by Western blot. RESULTS: The prevalence of chlamydia was 2.2% (95% CI, 0.4-6.4) in the prenatal clinic, 5.5% (95% CI, 1.8-12.4) in the STD clinic, 22.9% (95% CI, 10.4-40.1) among street sex workers, 8.2% (95% CI, 3.6-15.6) among sexually active female high school students, and 3.9% (95% CI, 1.3-8.9) among Gypsy women. Gonorrhea was found in only two populations: 2.2% (95% CI, 0.3-7.7) in the STD clinic, and 2.9% (95% CI, 0.1-14.9) among sex workers. No HIV-1 infection was detected. CONCLUSIONS: Urine screening was an efficient and accurate method for identifying groups at risk for STDs in the Czech Republic and Slovakia because sample collection was fast and noninvasive, and potential participation bias was reduced by high acceptability.

Adolescent↗

Modification of syphilitic genital ulcer manifestations by coexistent HIV infection.

BACKGROUND: Conflicting data exist regarding whether HIV infection leads to changes in the clinical manifestations and severity of genital ulcer disease (GUD). GOAL: To determine the impact of HIV on the etiology and clinical severity of GUD. STUDY DESIGN: From July 1990 to July 1992, consecutive patients presenting to the two Baltimore City Health Department (BCHD) Sexually Transmitted Diseases clinics were approached as candidates for enrollment in a prospective study to determine factors associated with the transmission and acquisition of sexually transmitted diseases (STDs). RESULTS: Of the 1368 patients who presented to the BCHD, 214 (16%) had genital ulcerations: 160 (21%) of 757 men and 54 (9%) of 611 women. Among the patients with GUD who had undergone HIV testing, 28 (14%) of 204 were infected with HIV: 25 (17%) of 151 men and 3 (6%) of 53 women. Although both groups-those infected with HIV and those not infected with HIV--presented with GUD of similar duration (10 versus 11 days; P = 0.17), multiple lesions were found more frequently in men with HIV infection than in uninfected men: 87% versus 62% (P = 0.02). Although not statistically significant, GUD in men with HIV infection more often were deep (64% versus 44%, respectively) rather than superficial (36% versus 57%, respectively; P = 0.08), and larger (505 mm(2) versus 109 mm 2; P = 0.06). Primary syphilis caused more GUD among men with HIV infection than among uninfected men: 9 (36%) of 25 versus 24 (19%) of 126, respectively (P < 0.01). Secondary syphilis was diagnosed with concomitant GUD more frequently among men with HIV infection than among uninfected men: 3 (13%) of 25 versus 3 (2%) of 123, respectively (P < 0.01). CONCLUSIONS: In this study, patients who presented with GUD were more likely to be infected with HIV. A higher proportion of men with HIV infection had multiple lesions, and the lesions were more likely to be caused by syphilis.

Adolescent↗

Adolescent chlamydia testing practices and diagnosed infections in a large managed care organization.

GOAL: To determine chlamydia screening practices and the resulting positive test results for adolescents enrolled in a large nonprofit managed care organization. STUDY DESIGN: The electronic medical records of all 12- to 19-year-olds enrolled in a large nonprofit managed care organization serving a demographically diverse patient population from January 1998 through December 1999 were reviewed retrospectively. RESULTS: Among the 43,205 female and 44,133 male managed care organization members, ages 12 to 19 years in 1998-1999, 7575 adolescents (8.7%) (6914 females [16%] and 661 males [1.5%]) were tested for chlamydia. Among the members tested, chlamydia was diagnosed in 1109 adolescents (14.6%) (983 females [14.2] and 126 males [19.1%]); 761 (68.6%) adolescents were retested for chlamydia; and 182 (16.4%) had repeat positive test results. The median time to diagnosis of a repeat infection was 6 months. CONCLUSIONS: Chlamydia imposes a large disease burden in the private, organized healthcare sector. Managed care organizations can use operational data to enhance chlamydia prevention services by defining testing practices and local disease prevalence.

Adolescent↗

Enhancing the specificity of the COBAS AMPLICOR CT/NG test for Neisseria gonorrhoeae by retesting specimens with equivocal results.

The COBAS AMPLICOR CT/NG test for Neisseria gonorrhoeae cross-reacts with certain strains of nonpathogenic Neisseria species. In some strains, the target sequence is identical to that of N. gonorrhoeae, whereas other strains have a small number of mismatches within the regions recognized by the primers or probe used in the COBAS AMPLICOR NG test. These cross-reactive strains are occasionally present in urogenital specimens, causing false-positive results in the COBAS AMPLICOR NG test. Analysis of the data generated in a large multicenter clinical trial showed that 2.9% of the specimens gave signals between A(660)s of 0.2 and 3.5 but that one-half of these equivocal specimens did not contain N. gonorrhoeae. Most of these equivocal specimens were correctly classified as true positive or true negative by retesting in duplicate and defining a PCR-positive result as two of three results with an A(660) of > or =2.0. If specimens had been classified as positive or negative based on a single test result using a cutoff of an A(660) of 0.2, specificity would have ranged from 96.2 to 98.9% depending on specimen type, sex, and presence of symptoms. By employing the equivocal zone-retesting algorithm, specificity increased to 98.6 to 99.9% with little effect (0.1 to 4.9% decrease) on sensitivity in most specimen types, enabling the test to achieve a positive predictive value of at least 90% in populations with a prevalence of 4% or higher. In lower-prevalence populations, the test could be used to screen for presumptive infections that would have to be confirmed by an independent test.

Adult↗