Paul D. Swenson

Targeted screening for primary HIV infection through pooled HIV-RNA testing in men who have sex with men

HIV-RNA testing may identify individuals with primary HIV infection. Men who have sex with men (MSM) having HIV testing through Public Health, Seattle and King County were screened for primary infection through pooled RNA testing. Eighty-one out of 3525 specimens (2.3%) had detectable antibody and RNA, and seven out of 3439 antibody-negative specimens (0.2%) had HIV RNA. Targeted screening for primary infection through pooled RNA testing in MSM is a useful addition to HIV case finding.

Herpes simplex virus type 2 (HSV-2) Western blot confirmatory testing among men testing positive for HSV-2 using the focus enzyme-linked immunosorbent assay in a sexually transmitted disease clinic.

Objective: The objective of this study was to define the positive predictive value (PPV) of the Focus herpes simplex virus type 2 (HSV-2) enzyme-linked immunosorbent assay (ELISA) in a low HSV-2 prevalence population and to develop a new test interpretation algorithm. Methods: HSV-2 Western blots were performed on sera from male sexually transmitted disease clinic patients testing HSV-2 ELISA-positive and used to define a new class of indeterminate HSV-2 ELISA result. HSV-2 Western blots were then prospectively performed on sequential sera with indeterminate HSV-2 ELISAs. Results: Ninety-one (84%) of 108 HSV-2 ELISA-positive sera tested HSV-2 Western blot-positive. Western blot positivity was more common in men without herpes simplex virus type 1 (HSV-1) antibody than in those with HSV-1 antibody (93% vs 76%, P = 0.02) and in men with a history or clinical evidence of genital lesions (88% vs 80%, P = 0.30). Selectively raising the ELISA index value defining HSV-2 positivity from >1.1 to ≥3.0 either among HSV-1-positive men or among those without a history or clinical evidence of genital lesions increased the PPV to ≥93%. Prospective evaluation of an algorithm incorporating HSV-1 serostatus found that 11 of 70 persons with indeterminate HSV-2 ELISAs were Western blot-positive. Conclusions: Clinicians should consider selectively using a higher index value to define Focus ELISA HSV-2 positivity based on either HSV-1 serostatus or clinical circumstances.

Epidemic lymphogranuloma venereum during epidemics of crack cocaine use and HIV infection in the Bahamas.

Background Since the early 1980s, the Bahamas has experienced sequential epidemics of freebase/crack cocaine use, genital ulcer–inguinal adenopathy disease (GUD), and heterosexual HIV infection. Goal To prospectively define the etiology of GUD in patients at the Princess Margaret Hospital during outbreaks of crack cocaine use, GUD, and HIV infection in the Bahamas. Study Design In Nassau, 47 consecutive patients with GUD underwent serologic testing for syphilis and for infections with HIV, herpes simplex virus type 2 (HSV-2), and Chlamydia trachomatis. Genital ulcer specimens were tested by culture and/or polymerase chain reaction (PCR) assay for Haemophilus ducreyi; by PCR and/or antigen assay for HSV; and by PCR for C trachomatis. Lymph node aspirates were tested by PCR for C trachomatis and H ducreyi. Results Twenty patients (43%) had HIV infection; eight had lymphogranuloma venereum (LGV), confirmed by PCR detection of C trachomatis sequences consistent with the L2 serovar; and nine others had possible LGV, on the basis of serum microimmunofluorescent C trachomatis antibody titers ≥256. Inguinal lymphadenopathy or bubo was present in 15 of 17 patients, who thus met the laboratory criteria for definite or possible LGV, and in 7 of 30 who did not meet such laboratory criteria (P < 0.001). Thirteen patients had confirmed genital herpes, seven had confirmed chancroid, and four had probable or possible primary syphilis. Conclusions The epidemics in the Bahamas of crack use, heterosexual HIV infection, and GUD apparently included epidemic transmission of LGV.

Sexual behaviors and risk factors for HIV infection among men who have sex with men in the Dominican Republic.

Objective:To describe self-reported types of sexual identity of men who have sex with men (MSM) in the Dominican Republic, assess sociodemographics and behavioral characteristics, and measure the prevalence of HIV-1 and syphilis. Design:Cross-sectional study of MSM recruited from a variety of community settings. Methods:A total of 354 men agreed to participate after giving verbal informed consent. Information was obtained using a standardized questionnaire assessing demographics and AIDS-relevant information. Blood was obtained for HIV and syphilis testing. Results:Five main sexual identity groups emerged: cross dressers, homosexuals, gigolos, bisexuals and heterosexuals. Receptive anal and oral intercourse were commonly reported by men self-identifying as cross dressers or homosexuals, whereas nearly all of the remaining three groups practiced only insertive intercourse. Sexual contact with women was also commonly reported; overall, consistent condom use was infrequent. HIV antibodies were detected in 11.0% and serologic evidence of syphilis was found in 7.3%. Factors independently associated with HIV infection included serologic evidence of syphilis, having visited at least one of four local brothels in 1975–1985, and having had receptive anal intercourse with four or more partners in the last 12 months. Conclusions:Syphilis, sexual practices and social context of sex (commercial sex), rather than sexual identity per se, were associated with HIV infection. The complex social networks of MSM in this setting, the tendency to practice either insertive or receptive sex, but not both, infrequent condom use, high rates of syphilis and the frequency of sex with women need to be taken into account for targeted HIV prevention programs to be successful.

Sexually transmitted infections in female sex workers: reduced by condom use but not by a limited periodic examination program.

Background and Objectives: The sexually transmitted diseases (STD) control program for female sex workers (FSW) in Lima, Peru, provided periodic serological tests for syphilis and cervical smears for gonococci, but not medication for STD or condoms. Goal of this Study: To assess program effectiveness. Study Design: We assessed prevalence of current STD and serum antibody to STD pathogens in FSW in relation to program participation and to condom use. Results: Program participation was not associated with significantly reduced rates of current gonococcal or chlamydial infections or Venereal Disease Research Laboratory (VDRL) titers ≥4 with reactive fluorescent treponemal antibody absorption (FTA‐ABS). However, regardless of control program participation, consistent condom use was associated with reduced prevalence of gonorrhea, and with significantly reduced seroreactivity for FTA‐ABS, C. trachomatis, anti‐hepatitis B core (HBc), and anti‐human T‐lymphotropic virus type I. Anti‐HBc was associated with years of receiving penicillin injections for syphilis prophylaxis. Conclusion: The scope, quality, and efficacy of STD control programs must be technically appropriate, well managed, and adequately financed. The safety of marginal programs warrants scrutiny.

Determination of HBsAg subtypes in different high risk populations using monoclonal antibodies

Monoclonal antibodies with restricted specificity were used in a modified commercial enzyme immunoassay for detection of HBsAg to subtype HBsAg in sera from 122 Southeast Asian refugees entering the United States, 62 inmates of a correctional facility, and 19 homosexual men. This method was able to classify HBsAg as aywl-2, ayw3, ayw4, ayr, adw2, adw4, or adr. The HBsAg subtype was identified in 183 (90.1%) of the serum samples, but the serum HBsAg concentration was too low to determine the subtype for the 20 (9.9%) remaining samples. Among the Southeast Asian refugees, aywl-2 was demonstrated in 35 (33.0%) of the subtyped serum samples, the adw2 subtype was identified in 33 (31.1%) sera, adr was detected in 37 (34.9%) sera, and the adw 4 subtype as found in 1 (0.9%). The most common subtypes in Vietnam, Laos, and Cambodia were aywl-2, adw2, and adr, respectively. In prison inmates, the ayw3 subtype accounted for 31 (52.5%) of the subtyped serum samples, an ayw2 variant and the adw2 subtype were each found in 13 (22.0%) sera, and the aywl-2 subtype was detected in 2 (3.4%) sera. Many of these inmates admitted intravenous drug use. Among homosexual men, the adw2 subtype was identified in 16 (88.9%) of the subtyped serum samples and the ayw3 subtype was detected in 2 (11.1%) sera. This subtyping method can distinguish between most of the nine major HBsAg subtypes and can be easily performed with these monoclonal antibodies and commercially available reagents.

Performance of an alternative HIV diagnostic algorithm using the ARCHITECT HIV Ag/Ab Combo assay and potential utility of sample-to-cutoff ratio to discriminate primary from established infection.

BACKGROUND The ARCHITECT HIV Ag/Ab Combo assay has a wide dynamic range for determining the sample-to-cutoff ratio (S/CO) values compared to other diagnostic HIV antibody assays. OBJECTIVES Determine the performance of an HIV testing algorithm that uses the ARCHITECT combo assay in the clinical setting and explore the utility of the signal-to-cutoff (S/CO) ratio to predict acute HIV-1 infection status. STUDY DESIGN A retrospective analysis of clinical samples from a hospital and referral population screened for HIV-1 infection between May 2011 and March 2013. Repeatedly reactive samples were tested using the Multispot HIV-1/HIV-2 rapid test and depending on that result, confirmatory orthogonal testing used the Western blot (WB) for HIV-1, Immunoblot for HIV-2 and nucleic acid amplification testing (NAAT) for HIV RNA. RESULTS A total of 21,317 test results were evaluated of which 509 were ARCHITECT repeatedly reactive; of these, 422 were Multispot-reactive only for HIV-1 (413 WB-positive; 9 indeterminate), 4 were Multispot-reactive for both HIV-1 and HIV-2 (one HIV-2 immunoblot-positive with 17 HIV-2 RNA copies/mL) and 83 were Multispot-non-reactive of which 15 were HIV-1 RNA positive and represented acute HIV-1 infection. There was an association among the ARCHITECT S/CO (median; IQR) values for antibody-negative (0.14; 0.11-0.16), acute infection (33; 2.1-76) and established HIV-1 infection (794; 494-1,029) (Kruskal-Wallis, p<0.0001). CONCLUSIONS The ARCHITECT combo assay with Multispot confirmation and reserved use of HIV-1 WB, HIV-2 Immunoblot and HIV NAAT for Multispot dual HIV-1/2 infection, and NAAT alone for Multispot-negative specimens, had a suitable test performance for detecting acute and established HIV infection.