Discordant rapid HIV tests: lessons from a low-resource community.

OBJECTIVES: HIV rapid antibody tests are widely used in Africa, but dual testing sometimes produces discordant results. It is not clear if discordant rapid HIV tests should always heighten suspicion by frontline health workers that early HIV infection is present. Some studies have reported that discordant rapid tests have value for identifying early HIV infection in high HIV prevalence populations. It is not known if rapid test performance influenced this conclusion, or if this observation will hold true for low HIV prevalence populations. We therefore explored the occurrence of discordant rapid HIV tests in a low-resource community. METHODS: A cross-sectional sample of HIV status-unaware adults with recent exposure to unsafe sex was assessed using a validated risk-based tool (University of North Carolina (UNC)-Malawi Risk Screening Score) for acute HIV infection. Participants received rapid testing with Determine™ HIV 1/2 and Uni-Gold™ HIV assays, plus plasma HIV-1 antigen testing with the COBAS® Ampliprep/COBAS® Taqman® HIV-1 assay, followed by western blot in those with detected HIV-1 antigen. RESULTS: Of 408 participants, 1.0% were confirmed to have established HIV infection. The discordance between rapid tests at initial screening was 2.45 and 2.94% when the two assays were used sequentially and simultaneously, respectively. Discordant rapid tests were strongly associated with risk scores > 2 [odds ratio (OR) 10.88; 95% confidence interval (CI) 2.35-50.43], and with detected HIV-1 RNA (OR 26.06; 95% CI 3.91-173.60). CONCLUSIONS: When the sample occurrence of discordance between the first and second tests is below 5%, discordant rapid tests in an adult with sexual risk behaviour should trigger strong suspicion of early HIV infection in low HIV prevalence populations.

Higher risk of AIDS or death in patients with lower CD4 cell counts after virally suppressive HAART.

BACKGROUND: The clinical implications of a failure to achieve high CD4 cell counts while receiving virally suppressive highly active antiretroviral therapy (HAART) are uncertain. METHODS: We analysed data from HIV-infected men participating in the Multicenter AIDS Cohort Study (MACS) to elucidate associations between CD4 cell counts achieved during virally suppressive HAART and risks of AIDS or death. Inclusion criteria were: CD4 cell count <200 cells/microL before HAART initiation; >or=2 viral load (VL) determinations after HAART initiation; and sustained viral suppression, defined as all VL <50 HIV-1 RNA copies/mL, but allowing a single VL of 50-1000 copies/mL. RESULTS: One hundred and twenty-one men were included; median age was 42 years. After first VL <50 copies/mL, six participants had a new AIDS diagnosis and seven died. The median CD4 cell count change/year (cells/microL) after first VL <50 copies/mL was zero among patients who either developed AIDS or died vs. 39 among those who did not meet either endpoint (P=0.119). After controlling for time from HAART initiation to first VL <50 copies/mL, age at first VL <50 copies/mL, history of AIDS and antiretroviral therapy (ART) experience before HAART, the hazard ratio for AIDS or death at CD4 cell count of 350 cells/microL was 10.7 (P=0.013), and at CD4 cell count of 201-350 vs. >350 cells/microL was 8.54 (P=0.014). CONCLUSION: In this cohort, lower CD4 cell count at the time of viral suppression was associated with increased risk of AIDS or death.

Mycobacterium tuberculosis and Mycobacterium africanum in stools from children attending an immunization clinic in Ibadan, Nigeria.

BACKGROUND: Tuberculosis is a major cause of childhood morbidity and mortality in Nigeria. Diagnosis of childhood tuberculosis is a global challenge making early treatment a mirage. In this study we investigated the stools of children for the presence of mycobacteria. METHODS: Stool samples from children aged 3 days to 3 years who presented for postnatal immunization at a large university-based clinic in Nigeria, were subjected to Ziehl-Neelsen staining. Samples with acid-fast bacilli were further processed using mycobacterial culture, spoligotyping, and deletion typing. RESULTS: One hundred and ninety-two stool samples from different children were collected and processed. Thirty (15.6%) had acid-fast bacilli. Of these, eight had Mycobacterium tuberculosis and one had Mycobacterium africanum. CONCLUSIONS: Approximately 5% (9/192) of apparently well children had evidence of potentially serious tuberculosis infection. The usefulness of stool specimens for diagnosing pediatric tuberculosis warrants further investigation.

Nevirapine toxicity.

The number of HIV-infected patients who are newly exposed to nevirapine is increasing worldwide. To minimize toxicity, clinicians must adhere to dosing guidelines, avoid prescribing the drug in patients with known increased risk of toxicity, and promptly recognize toxicities, which are mainly cutaneous and hepatic. These toxicities are more common with nevirapine than with efavirenz. Women with CD4 counts>250 cells/mm3 have particularly increased susceptibility to nevirapine toxicity. Improved understanding of the pathogenesis of nevirapine toxicity, and its relationship with pharmacokinetic parameters, genetic factors and cellular immune kinetics will enhance our ability to reduce the risk to the HIV-infected individual.

Antiretroviral treatment: current approach and future prospects.

Pharmacologic treatment of HIV infection involves the combination of drugs that exert their antiretroviral effects at different stages in the life-cycle of the virus. Strongpublic-health programs are necessary for HIV control. To be successful in treating HIV, the clinician must establish a treatment alliance with the patient to forge optimal adherence to the treatment regimen. Potential adverse reactions,toxicities and drug-drug interactions must be understood and detected early. Disparity exists in the treatment of HIV between most African and western countries and can be bridged through improved access to drugs and treatment infrastructure. The search for a cure is led by ongoing research in novel concepts such as structured treatment intervention and immune-based therapy.

Use of thalidomide in HIV infection.

Despite its disastrous past, thalidomide has reentered the medical community. This article reviews available evidence for its potential application to the treatment of some complications of HIV infection. HIV-related conditions in which thalidomide may be useful include aphthous ulcers, wasting, diarrhea, and nodular prurigo. Vigilance must be maintained to minimize adverse effects and prevent fetal exposure.

HIV-associated wasting: brief review and discussion of the impact of oxandrolone.

This is a brief review of human immunodeficiency virus (HIV)-associated wasting with expanded discussion of one treatment agent, oxandrolone. HIV-associated wasting is the involuntary loss of more than 10% of baseline body weight in the presence of chronic diarrhea, weakness, or fever lasting longer than 30 days. For patients, this clinical syndrome has special importance because it affects not only their survival but also their physical appearance and social interactions. Pharmacologic treatment is only one of the many approaches that need to be explored in every patient who presents with this condition. In 1964, oxandrolone became the first drug approved for the treatment of wasting. Since then its role has expanded to HIV-associated wasting. As an anabolic agent oxandrolone reverses many of the metabolic abnormalities characteristic of HIV-associated wasting leading to dose dependent increase in nitrogen retention. Similar to many other HIV treatments, gaps exist in our knowledge of the role of oxandrolone in HIV-associated wasting. These gaps will be filled only by years of field exposure and further clinical research.

AIDS-related primary CNS lymphoma: a brief review.

Primary CNS lymphoma, which has a strong association with Epstein-Barr virus, was increasing in incidence in patients with AIDS before the introduction and widespread use of combination antiretroviral therapy. The diagnostic strategies for primary CNS lymphoma, including contrast-enhanced CT or MRI and brain biopsy, are well established. The use of a combination of diagnostic tools to reduce the need for brain biopsy is currently being evaluated. The clinical outcome with current treatments for primary CNS lymphoma in HIV-infected persons remains relatively discouraging.