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HIV Seropositivity: HELP
Articles by David A. Lewis
Based on 8 articles published since 2008

Between 2008 and 2019, D. A. Lewis wrote the following 8 articles about HIV Seropositivity.
+ Citations + Abstracts
1 Clinical Trial Acute HIV infections among men with genital ulcer disease in South Africa. 2010

Paz Bailey, G / Sternberg, M / Lewis, D A / Puren, A. ·Del Valle University of Guatemala and Centers for Disease Control and Prevention Collaboration, Guatemala City, Guatemala. gpaz@gt.cdc.gov ·J Infect Dis · Pubmed #20443734.

ABSTRACT: We investigated acute human immunodeficiency virus (HIV) infection among men enrolled in a genital ulcer treatment trial in South Africa. HIV-negative participants were tested at baseline by HIV RNA polymerase chain reaction and followed up after 1 month to measure HIV seroconversion. There were 228 HIV-negative men at baseline; 10 were positive for HIV RNA, and 8 seroconverted to HIV at day 28. The prevalence of acute HIV among HIV-negative men at baseline was 18 (7.9%) of 228 men (95% confidence interval [CI], 4.4-11.4) and 18 (2.9%) of 615 men (95% CI, 1.6-4.3) in the overall study population. These data highlight the importance of genital ulcer patients in HIV transmission. Trial Registration. ClinicalTrials.gov identifier: NCT00164424 .

2 Article Validation of cervical cancer screening methods in HIV positive women from Johannesburg South Africa. 2013

Firnhaber, Cynthia / Mayisela, Nomtha / Mao, Lu / Williams, Sophie / Swarts, Avril / Faesen, Mark / Levin, Simon / Michelow, Pam / Omar, Tanvier / Hudgens, Michael G / Williamson, Anna-Lise / Allan, Bruce / Lewis, David A / Smith, Jennifer S. ·Faculty of Health Science Centre, Department of Medicine, University of Witwatersrand, Johannesburg, South Africa. cindy.firnhaber@righttocare.org ·PLoS One · Pubmed #23326441.

ABSTRACT: BACKGROUND: HIV-infected women are at increased risk for developing cervical cancer. Women living in resource-limited countries are especially at risk due to poor access to cervical cancer screening and treatment. We evaluated three cervical cancer screening methods to detect cervical intraepithelial neoplasia grade 2 and above (CIN 2+) in HIV-infected women in South Africa; Pap smear, visual inspection with 5% acetic acid (VIA) and human papillomavirus detection (HPV). METHODS: HIV-infected women aged 18-65 were recruited in Johannesburg. A cross-sectional study evaluating three screening methods for the detection of the histologically-defined gold standard CIN-2 + was performed. Women were screened for cervical abnormalities with the Digene HC2 assay (HPV), Pap smear and VIA. VIA was performed by clinic nurses, digital photographs taken and then later reviewed by specialist physicians. The sensitivity, specificity and predictive valves for CIN-2 + were calculated using maximum likelihood estimators. RESULTS: 1,202 HIV-infected women participated, with a median age of 38 years and CD4 counts of 394 cells/mm(3). One third of women had a high grade lesion on cytology. VIA and HPV were positive in 45% and 61% of women respectively. Estimated sensitivity/specificity for HPV, Pap smear and VIA for CIN 2+ was 92%/51.4%, 75.8%/83.4% and 65.4/68.5% (nurse reading), respectively. Sensitivities were similar, and specificities appeared significantly lower for the HPV test, cytology and VIA among women with CD4 counts ≤200 cells/mm(3) as compared to CD4 counts >350 cells/mm(3). CONCLUSIONS: Although HPV was the most sensitive screening method for detecting CIN 2+, it was less specific than conventional cytology and VIA with digital imaging review. Screening programs may need to be individualized in context of the resources and capacity in each area.

3 Article Prevalence and associations of genital ulcer and urethral pathogens in men presenting with genital ulcer syndrome to primary health care clinics in South Africa. 2012

Lewis, David A / Müller, Etienne / Steele, Lisa / Sternberg, Maya / Radebe, Frans / Lyall, Michael / Ballard, Ronald C / Paz-Bailey, Gabriela. ·Centre for HIV and Sexually Transmitted Infections, National Institute for Communicable Diseases, National Health Laboratory Service, Sandringham, South Africa. davidl@nicd.ac.za ·Sex Transm Dis · Pubmed #23064538.

ABSTRACT: BACKGROUND: This study aimed to determine the prevalence of genital ulcer and urethral pathogens, as well as their association with clinical features, in men with genital ulcer disease (GUD) enrolled in a clinical trial. METHODS: Clinical data were collected by questionnaire. Ulcer swabs were tested for herpes simplex viruses (HSV-1/2), Treponema pallidum, Haemophilus ducreyi, and Chlamydia trachomatis L1-L3. First-pass urine was tested for urethral pathogens, namely Neisseria gonorrhoeae, C. trachomatis, Trichomonas vaginalis, and Mycoplasma genitalium. Pathogens were detected by real-time molecular assays. Blood was tested for HIV, HSV-2, and syphilis-associated antibodies. Pathogens and clinical associations were investigated using the χ test. RESULTS: A total of 615 men with GUD were recruited. Herpes simplex virus (HSV-1, 4.2%; HSV-2, 98.2%) and bacterial pathogens were detected in 451 (73.6%) and 48 (7.8%) of genital ulcers, respectively. Human immunodeficiency virus, HSV-2, and treponemal antibodies were detected in 387 (62.9%), 434 (70.6%), and 141 (23.0%) men, respectively, whereas 54 men (8.8%) were rapid plasmin reagin (RPR) seropositive. A total of 223 urethral infections were diagnosed in 188 men (30.6%), including 69 (11.2%) M. genitalium, 64 (10.4%) T. vaginalis, 60 (9.8%) C. trachomatis, and 30 (4.9%) N. gonorrhoeae infections. Dysuria was reported by 170 men (27.6%), and 69 men (11.5%) had urethral discharge on examination. Urethral pathogens were detected in 102/409 (24.9%) men without these clinical features. CONCLUSIONS: Herpes accounted for most GUD cases and urethral pathogen coinfections were common. Erythromycin, dispensed to treat infrequent chancroid and lymphogranuloma venereum cases, provided additional treatment of some asymptomatic urethral pathogens. Additional antibiotics would be required to treat asymptomatic trichomoniasis and gonorrhea.

4 Article Urethritis/cervicitis pathogen prevalence and associated risk factors among asymptomatic HIV-infected patients in South Africa. 2012

Lewis, David A / Chirwa, Tobias F / Msimang, Veerle M Y / Radebe, Frans M / Kamb, Mary L / Firnhaber, Cynthia S. ·Centre for HIV and STIs, National Institute for Communicable Diseases, National Health Laboratory Service, Johannesburg, South Africa. davidl@nicd.ac.za ·Sex Transm Dis · Pubmed #22706215.

ABSTRACT: BACKGROUND: To determine sexually transmitted infection (STI) prevalence, and patient characteristics associated with detection of urethritis/cervicitis pathogens, among HIV-infected individuals offered voluntary STI screening at a South African HIV treatment center. METHODS: Individuals, asymptomatic for genital discharge, were screened for Neisseria gonorrhoeae (NG), Chlamydia trachomatis, Trichomonas vaginalis (TV), Mycoplasma genitalium (MG) infections (real-time polymerase chain reaction assay), for syphilis and herpes simplex type 2 (serologically), and for bacterial vaginosis and Candida (microscopy, women only). Patients' most recent CD4 and viral load results were recorded. Demographic, clinical, and behavioral data were collected by nurse-administered questionnaire. RESULTS: Compared with men (n = 551), women (n = 558) were younger (mean age, 35.0 vs. 37.9 years; P < 0.001), reported more STIs in the past year (65.5% vs. 56.5%; P = 0.002), had more urethritis/cervicitis pathogens detected (21.3% vs.16.4%, P = 0.035), and were less aware of their partner's HIV status (53.1% vs. 62.3%; P = 0.007). The overall prevalence of individual urethritis/cervicitis pathogens was TV (7.6%), MG (6.1%), NG (5.4%), and C. trachomatis (2.1%). Multivariate analysis highlighted 4 significant factors associated with the detection of specific urethritis/cervicitis pathogens, namely female gender (TV, adjusted odds ratio [aOR] 2.53, 95% confidence interval [CI]: 1.47-4.37), having a regular sexual partner in the past 3 months (NG, aOR 2.26, 95% CI: 1.01-5.08), suboptimal condom use with regular partners (TV, aOR 2.07, 95% CI: 1.25-3.42), and a history of genital warts in the past year (NG, 2.25, 95% CI: 1.26-4.03). CONCLUSIONS: Asymptomatic urethritis/cervicitis pathogens were highly prevalent in this population. Few urethritis/cervicitis pathogen-associated patient characteristics were identified, emphasizing the need for affordable STI diagnostics to screen HIV-infected patients.

5 Article Episodic therapy for genital herpes in sub-saharan Africa: a pooled analysis from three randomized controlled trials. 2011

Weiss, Helen A / Paz Bailey, Gabriela / Phiri, Sam / Gresenguet, Gerard / LeGoff, Jerome / Pepin, Jacques / Lewis, David A / Belec, Laurent / Hoffman, Irving F / Miller, William C / Mayaud, Philippe. ·London School of Hygiene and Tropical Medicine, London, United Kingdom. helen.weiss@lshtm.ac.uk ·PLoS One · Pubmed #21799914.

ABSTRACT: BACKGROUND: A randomized controlled trial in South Africa found a beneficial effect of acyclovir on genital ulcer healing, but no effect was seen in trials in Ghana, Central African Republic and Malawi. The aim of this paper is to assess whether the variation in impact of acyclovir on ulcer healing in these trials can be explained by differences in the characteristics of the study populations. METHODOLOGY/PRINCIPAL FINDINGS: Pooled data were analysed to estimate the impact of acyclovir on the proportion of ulcers healed seven days after randomisation by HIV/CD4 status, ulcer aetiology, size and duration before presentation; and impact on lesional HIV-1. Risk ratios (RR) were estimated using Poisson regression with robust standard errors. Of 1478 patients with genital ulcer, most (63%) had herpetic ulcers (16% first episode HSV-2 ulcers), and a further 3% chancroid, 2% syphilis, 0.7% lymphogranuloma venereum and 31% undetermined aetiology. Over half (58%) of patients were HIV-1 seropositive. The median duration of symptoms before presentation was 6 days. Patients on acyclovir were more likely to have a healed ulcer on day 7 (63% vs 57%, RR = 1.08, 95% CI 0.98-1.18), shorter time to healing (p = 0.04) and less lesional HIV-1 RNA (p = 0.03). Small ulcers (<50 mm(2)), HSV-2 ulcers, first episode HSV-2 ulcers, and ulcers in HIV-1 seropositive individuals responded best but the better effectiveness in South Africa was not explained by differences in these factors. CONCLUSIONS/SIGNIFICANCE: There may be slight benefit in adding acyclovir to syndromic management in settings where most ulcers are genital herpes. The stronger effect among HIV-1 infected individuals suggests that acyclovir may be beneficial for GUD/HIV-1 co-infected patients. The high prevalence in this population highlights that genital ulceration in patients with unknown HIV status provides a potential entry point for provider-initiated HIV testing.

6 Article Association between cervical dysplasia and human papillomavirus in HIV seropositive women from Johannesburg South Africa. 2010

Firnhaber, Cynthia / Van Le, Hoa / Pettifor, Audrey / Schulze, Doreen / Michelow, Pam / Sanne, Ian M / Lewis, David A / Williamson, Anna-Lise / Allan, Bruce / Williams, Sophia / Rinas, Allen / Levin, Simon / Smith, Jennifer S. ·Department of Medicine, University of Witwatersrand, Johannesburg, South Africa. cfirnhaber@witshealth.co.za ·Cancer Causes Control · Pubmed #19949850.

ABSTRACT: OBJECTIVE: To examine the association between CD4 counts, HPV infection and the risk of cervical neoplasia among HIV-seropositive women. METHODS: A cross-sectional observational study was conducted among 1,010 HIV-seropositive women using cytology-based Pap smears. HPV DNA testing using Linear Array genotyping assay (Roche) was carried out in a subset of 191 patients. Multivariable-adjusted prevalence ratios (mPR) and 95% confidence intervals (CIs) were estimated with log-binomial regression. RESULTS: Among 1,010 HIV-seropositive women, the prevalence of AGC/ASCUS, LSIL and HSIL or greater was 8.3, 23.5 and 18.0%, respectively. The risk of cervical lesions was higher with CD4 < 200 cells/mm(3) vs. CD4 levels > 500/mm(3). HPV types 16 (41.7%) and HPV 56 (22.2%) were the most common types in HSIL cases. Women with CD4 levels < 200/mm(3) had a higher prevalence of HPV types 16 (p < 0.01) and 66 (p = 0.04). No statistical relationship between cervical lesions and HAART use was found. CONCLUSION: The burden of HPV infection and HSIL was high and correlated with HIV-induced immunosuppression. HPV 16 was the most common type in HSIL and increased in prevalence with greater immune suppression. Prophylactic HPV 16 vaccination could prevent approximately 40% of HSIL cases. Strengthening screening programs is imperative in this population.

7 Article Human papillomavirus (HPV) infection in heterosexual South African men attending sexual health services: associations between HPV and HIV serostatus. 2010

Müller, Etienne E / Chirwa, Tobias F / Lewis, David A. ·Sexually Transmitted Infections Reference Centre, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham, Johannesburg, South Africa. etiennem@nicd.ac.za ·Sex Transm Infect · Pubmed #19880970.

ABSTRACT: OBJECTIVES: To investigate the distribution of human papillomavirus (HPV) genotypes and determine the associations between HPV infection and HIV coinfection in sexually active heterosexual men with anogenital warts (GW), male urethral discharge or asymptomatic men. METHODS: Valid specimens for HPV genotyping were obtained from three patient groups consisting of 108 men with GW, 56 men with urethral discharge syndrome and 50 asymptomatic men attending for HIV voluntary counselling and testing. The Linear Array HPV Genotyping Test was used to determine the HPV genotype distribution among study participants. Sera were tested for HIV antibodies using two commercial rapid tests. RESULTS: The prevalence of anogenital HPV among study participants was 78% (166). HPV DNA was detected in 100% (108) of GW, 48% (27) of men with urethral discharge syndrome and 62% (31) of voluntary counselling and testing participants. HPV types 6, 11, 16 and 18 were prevalent as either single or combined infections in 81% (134) of all HPV-positive study participants. HPV types 6 and/or 11 were significantly higher among GW patients (p<0.001). After adjusting for patient groups, HIV seropositivity was significantly associated with multiple HPV infections (OR=3.98, 95% CI 1.58 to 10.03) but not with the presence of a foreskin (OR=0.67, 95% CI 0.32 to 1.40). CONCLUSIONS: Infections with HPV were prevalent among sexually active heterosexual men attending the men's sexual health clinic. Associations were observed between HIV coinfection and multiple HPV infections. Further population-based studies on the prevalence of HPV genotypes are required to determine if men should be included in any future national HPV vaccination programme in South Africa.

8 Article Escalation in the relative prevalence of ciprofloxacin-resistant gonorrhoea among men with urethral discharge in two South African cities: association with HIV seropositivity. 2008

Lewis, D A / Scott, L / Slabbert, M / Mhlongo, S / van Zijl, A / Sello, M / du Plessis, N / Radebe, F / Wasserman, E. ·STI Reference Centre, National Institute for Communicable Diseases, Private Bag X4, Sandringham 2131, South Africa. davidl@nicd.ac.za ·Sex Transm Infect · Pubmed #18596070.

ABSTRACT: OBJECTIVES: The objectives of this study were to assess the prevalence of ciprofloxacin-resistant gonorrhoea in two South African cities and to investigate the association between the isolation of ciprofloxacin-resistant Neisseria gonorrhoeae and the HIV serostatus of patients. METHODS: Gonococci were cultured from endourethral swabs taken from consecutive men with urethritis attending clinics in Johannesburg and Cape Town. Minimum inhibitory concentrations (MIC) for ciprofloxacin and ceftriaxone were determined with E-tests. Isolates with a ciprofloxacin MIC of 1 mg/l or greater were defined as resistant and isolates with a ceftriaxone MIC of 0.25 mg/l or less were defined as susceptible. Rapid tests were used to screen and confirm the presence of HIV antibodies. Survey data from 2004 were used as a baseline to assess trends in gonococcal resistance to ciprofloxacin. RESULTS: In 2004, the prevalence of ciprofloxacin resistance was 7% in Cape Town and 11% in Johannesburg. In 2007, 37/139 (27%) Cape Town isolates and 47/149 (32%) Johannesburg isolates were resistant to ciprofloxacin; in comparison with 2004 data, this represents 2.9-fold and 1.9-fold increases, respectively. All isolates were fully susceptible to ceftriaxone. There was a significant association between HIV seropositivity and the presence of ciprofloxacin-resistant gonorrhoea among patients (p = 0.034). CONCLUSIONS: Johannesburg and Cape Town have witnessed significant rises in the prevalence of ciprofloxacin-resistant gonorrhoea among men with urethritis. The resistant phenotype is linked to HIV seropositivity. There is now an urgent need to change national first-line therapy for presumptive gonococcal infections within South Africa.