Operational challenges in delivering CD4 diagnostics in sub-Saharan Africa.

Access to reliable and low cost CD4 T-cell enumeration to stage illness and monitor anti-retroviral therapy remains elusive in resource-limited settings. We report challenges in delivering CD4 testing using the microcapillary Fluorescence-Activated Cell Sorter (FACS) methodology (Guava EasyCD4 instrument Guava Technologies, Hayward) in Burkina Faso and Zimbabwe. Resources, instruments, reagents, and training were provided to local laboratories within the existing infrastructure and data on CD4 were collected from routine laboratory testing. Challenges encountered included frequent instrument breakdown; poor manufacturer maintenance; difficulties in managing reagent stocks; high technician turnover; reliance on antiquated data management systems; redundant service provision; and lack of repeat testing in male HIV+ patients and in patients with higher CD4 counts after initial staging. While adopting newer, less expensive technologies such as fluorescent platforms and point of care tests can facilitate access to lower cost CD4 testing, our experience suggests that supply chain, corporate commitment to implementation, and community factors also require consideration.

Alanine aminotransferase levels are not significantly elevated in patients with HIV/HBV co-infection and lamivudine resistance.

In hepatitis B virus (HBV) monoinfection, alanine aminotransferase (ALT) levels are linearly correlated with HBV DNA levels and lamivudine resistance. In human immunodeficiency virus (HIV)/HBV co-infection, little is known about the association between ALT, HBV DNA, and lamivudine resistance. We assessed HBV DNA, lamivudine resistance and ALT levels in 45 time points in 11 patients with HIV/HBV co-infection during lamivudine-containing antiretroviral therapy. High HBV DNA levels (>10(6) copies/mL) and lamivudine resistance developed in 45% and 91% of patients, respectively. However, ALT levels were not elevated in the setting of high HBV DNA levels (mean ALT, 48 IU/mL) or lamivudine resistance (mean ALT, 44 IU/mL). HBV viraemia and lamivudine resistance during extended lamivudine-containing antiretroviral therapy are common in HIV/HBV co-infection, occurring in the absence of significant ALT elevations. In HIV/HBV co-infection, measurement of HBV DNA and HBV resistance mutations may identify HBV virological failure before biochemical changes and should be routinely used in the management of HIV/HBV co-infection.

Psychiatric co-morbidity in vulnerable populations receiving primary care for HIV/AIDS.

Considerable evidence suggests that people with HIV disease are significantly more distressed than the general population, yet psychiatric disorders are commonly under-detected in HIV care settings. This study examines the prevalence of three stress-related psychiatric diagnoses--depression, posttraumatic stress disorder (PTSD), and acute stress disorder (ASD), among a vulnerable population of HIV-infected patients. Among approximately 350 patients attending two county-based HIV primary care clinics, 210 participants were screened for diagnostic symptom criteria for depression, PTSD, and ASD. Standardized screening measures used to assess for these disorders included the Beck Depression Inventory, the Posttraumatic Stress Checklist, and the Stanford Acute Stress Questionnaire. High percentages of HIV-infected patients met screening criteria for depression (38 per cent), PTSD (34 per cent), and ASD (43 per cent). Thirty eight percent screened positively for two or more disorders. Women were more likely to meet symptom criteria for ASD than men (55 per cent vs. 38 per cent, OR=1.94, CI95 per cent=1.1-3.5). ASD was detected more commonly among African-American and white participants (51 per cent and 50 per cent respectively), compared with other ethnic groups. Latinos were least likely to express symptoms of ASD (OR=0.52, CI95 per cent=0.29-0.96). Of the 118 patients with at least one of these disorders, 51 (43 per cent) reported receiving no concurrent mental health treatment. Patients with HIV/AIDS who receive public healthcare are likely to have high rates of acute and posttraumatic stress disorders and depression. These data suggest that current clinical practices could be improved with the use of appropriate tools and procedures to screen and diagnose mental health disorders in populations with HIV/AIDS.

Characterization of the HIV-1 specific humoral immune response during highly active antiretroviral therapy (HAART).

Plasma samples from 19 patients were analyzed for HIV-1 directed humoral immune responses prior to and 1 year after initiation of HAART. Eight of the subjects were classified as virologic successes, defined by a >100-fold decrease in viral load (VL) over the 1-year study period and a final VL <500 copies/ml. The eleven HAART failures were defined as subjects with <10-fold decrease in VL. At study entry (before HAART), VL and CD4 counts were similar between the two groups. Humoral immune responses before therapy and after 1 year of therapy were measured by V3 peptide antibody binding titers and neutralization of HIV-1 MN and four subtype B clinical isolates. Before HAART, neutralizing antibody titers to the clinical isolates and HIV(MN), as well as HIV V3 envelope binding titers to several V3 peptides, were significantly higher among treatment successes compared with treatment failures. After 1 year on HAART, neutralization declined in titer and narrowed in specificity among the HAART successes. In contrast, a significant increase in both neutralizing titer and breadth was seen among HAART failures.

Sociodemographic characteristics associated with medical appointment adherence among HIV-seropositive patients seeking treatment in a county outpatient facility.

BACKGROUND: Adherence is a major problem facing HIV-seropositive patients. Low adherence has been associated with faster disease progression as well as development of drug-resistant strains of HIV. Thus it is critical to understand factors associated with treatment compliance. This study examined the independent contributions of disease severity, age, gender, household income, homelessness, ethnicity, and sexual orientation on appointment adherence. METHODS: Participants (n = 671) scheduled for appointments in an outpatient county treatment facility for HIV-related medical care completed demographic questionnaires and clinic staff collected appointment attendance data. RESULTS: Multiple regression analyses indicated that patients diagnosed with AIDS, older in age, and receiving a higher income were more likely to keep medical appointments. Additionally, African American ethnicity and identifying as heterosexual were associated with missing scheduled medical appointments. CONCLUSIONS: These data suggest that cultural and sociodemographic characteristics influence patients' adherence to outpatient services. Implications for interventions aimed at increasing medical adherence are discussed.

Phenotypic hypersusceptibility to non-nucleoside reverse transcriptase inhibitors in treatment-experienced HIV-infected patients: impact on virological response to efavirenz-based therapy.

BACKGROUND: Enhanced susceptibility to non-nucleoside reverse transcriptase inhibitors (NNRTI) was recently described in association with increased resistance to nucleoside analogs (nucleoside reverse transcriptase inhibitors; NRTI). OBJECTIVES: To determine the prevalence of NNRTI hypersusceptibility, the genotypic correlates, and its impact on virologic response to efavirenz-based salvage therapy. METHODS: Genotype and phenotype testing was performed retrospectively on baseline isolates from 30 patients who received salvage therapy containing efavirenz. NNRTI hypersusceptibility was defined as a 50% inhibitory concentration (IC(50)) of < 0.5 that of the wild-type control. RESULTS: Eight isolates had major NNRTI mutations. Among the 22 isolates with no major NNRTI mutations, 11 (50%) were hypersusceptible to efavirenz, 10 (45%) to delavirdine, and eight (36%) to nevirapine. Among eight isolates with NNRTI mutations, NNRTI resistance was present, but at lower than expected levels. The number of NRTI mutations was correlated inversely with the fold decrease in susceptibility to efavirenz (Spearman's rho, -0.57; P = 0.005), delavirdine (rho, -0.43; P = 0.04), and nevirapine (rho, -0.69; P < 0.001). Excluding subjects with NNRTI mutations, subjects with efavirenz hypersusceptibility at baseline had significantly better virologic suppression over 24 weeks than those without efavirenz hypersusceptibility (P < 0.001). CONCLUSION: NNRTI hypersusceptibility is common in heavily treated but NNRTI naive patients and is related directly to NRTI resistance mutations. Among patients receiving efavirenz-containing regimens, NNRTI hypersusceptibility was associated with an improved virologic outcome after 24 weeks of therapy. A reversal of phenotypic resistance was seen in patients with NNRTI mutations in the presence of multiple NRTI mutations, but no obvious virologic benefit of this phenomenon was seen in this study.

Efavirenz- and adefovir dipivoxil-based salvage therapy in highly treatment-experienced patients: clinical and genotypic predictors of virologic response.

OBJECTIVE: To determine the impact of prior nonnucleoside reverse transcriptase inhibitor (NNRTI) therapy, genotypic resistance, and other variables on response to efavirenz (EFV)- and adefovir dipivoxil (ADV)-based salvage therapy. DESIGN: Retrospective clinical cohort study. SETTING: One university and one community-based HIV clinic. STUDY SUBJECTS: All 33 patients who were coenrolled in both the EFV and ADV expanded access programs. INTERVENTIONS: Patients received EFV 600 mg/day and ADV 120 mg/day in addition to other antiretroviral agents. OUTCOME MEASURE: HIV viral load (<500 copies/ml) at 12 and 24 weeks. RESULTS: 10 of 33 (30%) patients at 12 weeks and 8 of 33 (24%) patients at 24 weeks had viral loads <500 copies/ml. Prior NNRTI use and a history of any NNRTI-associated mutations predicted failure. Patients with Y181C or G190A single mutations had an initial greater magnitude of viral load suppression than those with K103N, but this advantage was short lived. No one with any NNRTI mutations responded with a viral load <500 copies/ml at 12 or 24 weeks. CONCLUSIONS: EFV/ADV-based salvage yielded viral load suppression at 24 weeks in 42% (8 of 19) of patients who were highly NRTI and protease inhibitor experienced but NNRTI naive. NNRTI-experienced study subjects had a poor response regardless of the specific NNRTI resistance mutation they harbored.

Relationships of perceived stress to coping, attachment and social support among HIV-positive persons.

The purpose of this study was to examine the relationships of coping, attachment style and perceived social support to perceived stress within a sample of HIV-positive persons. Participants were 147 HIV-positive persons (80 men and 67 women). Multiple regression analysis was used to examine the relationships of the demographic variables, AIDS status, three coping styles, three attachment styles and perceived quality of general social support with total score on the Perceived Stress Scale (PSS). PSS score was significantly associated with less income, greater use of behavioural and emotional disengagement in coping with HIV/AIDS, and less secure and more anxious attachment styles. These results indicate that HIV-positive persons who experience the greatest stress in their daily lives are those with lower incomes, those who disengage behaviourally/emotionally in coping with their illness, and those who approach their interpersonal relationships in a less secure or more anxious style.

Quantitation of human immunodeficiency virus by culture and polymerase chain reaction in response to didanosine after long-term therapy with zidovudine.

Measurements of human immunodeficiency virus by quantitative RNA and DNA polymerase chain reaction (PCR), cell and plasma infectivity dilution cultures, and immune complex-disassociated p24 antigen-capture ELISA were made repeatedly in 10 subjects receiving long-term zidovudine treatment before and after therapy was changed to didanosine. Comparison of baseline assays showed that quantitative cell cultures, plasma RNA, and proviral DNA were measurable in all subjects and that cell culture results were significantly correlated with measures of nucleic acids. Plasma viremia (as indicated by culture) and p24 antigen were detected in three measurements in 3 of 8 and 6 of 10 subjects, respectively. Significant decreases in plasma RNA and cell dilution cultures from baseline were maintained for up to 6 months after initiation of didanosine therapy. These findings demonstrate a decrease in virus burden with the use of didanosine; however, continued detection of plasma RNA suggests that additional antiviral therapy will be required to suppress viral replication.

Toxoplasmosis in patients with cancer.

The unusual occurrence, protein manifestations, and often devastating consequences of toxoplasmosis in patients with cancer emphasize the need for clinical acumen in the diagnosis and management of this disorder. Toxoplasmosis in patients with cancer has most commonly been described in association with Hodgkin's disease. It has also been reported, usually in the setting of treatment with antineoplastic agents, in patients with other lymphoproliferative disorders, hematologic malignancies, and solid tumors. In this review, among patients for whom the diagnosis was made early enough to begin specific treatment, conditions of 68% improved; this finding was in marked contrast to the severe morbidity and mortality observed for untreated individuals. The high mortality in the untreated group reflects the general debilitation and severe immunocompromise of these patients. Therefore, although toxoplasmosis contributed to a poor prognosis, it was not necessarily always the proximate cause of death.

Prevalence of Toxoplasma infection in a cohort of homosexual men at risk of AIDS and toxoplasmic encephalitis.

The purpose of this study was to characterize the epidemiologic, clinical, and laboratory parameters of a cohort of men at risk of AIDS-associated toxoplasmic encephalitis. One hundred seventeen (11%) of the 1,073 participants at the time of enrollment into the Chicago Multicenter AIDS Cohort Study (MACS) were seropositive for Toxoplasma antibodies. Significant differences in prevalence of antibodies between African-American, Hispanic, or white men were not observed (p = 0.49). One hundred one (86%) of the 117 antibody-positive participants had at least one follow-up serology performed and 6 (6%) of the 101 had a significant rise in IgG antibody titer on subsequent visits. Five of six participants with a significant rise in titer were also seropositive for HIV-1 at entry or seroconverted during the study. A trend toward higher IgG Toxoplasma titers and prevalence of IgM antibodies in participants seropositive for HIV-1 was observed, but the differences did not reach statistical significance. There was no evidence that the presence of Toxoplasma infection predisposed to development of CD4+ depletion or AIDS. None of the 183 individuals in the cohort who developed AIDS and who were seronegative for Toxoplasma antibodies developed toxoplasmic encephalitis. In contrast, of the 13 persons who developed AIDS and who were positive for Toxoplasma antibodies, 5 (38%) developed toxoplasmic encephalitis. Prevalence of Toxoplasma antibodies in the MACS population was independent of HIV-1 serostatus. Toxoplasma infection does not appear to predispose to progression of HIV-1 infection. The risk of development of toxoplasmic encephalitis in persons with AIDS and chronic Toxoplasma infection may have been underestimated by previous retrospective studies.

Pharmacokinetics of zidovudine alone and in combination with oxazepam in the HIV infected patient.

This three-phase study was designed to determine if a pharmacokinetic drug-drug interaction exists between zidovudine and oxazepam. Six individuals infected with human immunodeficiency virus (HIV) and receiving zidovudine at 500 mg daily, with normal renal and hepatic function, were enrolled. During phase I, zidovudine pharmacokinetics were studied after steady-state oral administration (100 mg every 4 h) and after a single dose (70 mg) of intravenous zidovudine. Phase II consisted of a single oral dose (30 mg) of oxazepam followed by a 48-h blood sampling period. Phase III began with 48 h of concomitant zidovudine, 100 mg orally every 4 h, and oxazepam, 15 mg orally every 8 h, followed by concomitant dosing of intravenous zidovudine and oral oxazepam. Zidovudine concentrations were determined by radioimmunoassay. Oxazepam concentrations were determined with use of a fluorescence polarization immunoassay. The calculated bioavailability was 0.61 for zidovudine alone and 0.75 when administered in combination with oxazepam (p = 0.16). Plasma half-life for oral zidovudine alone and in combination with oxazepam was 1.17 h versus 0.99 h, respectively (p = 0.25), and 1.38 h versus 1.15 h (p = 0.38) for intravenous zidovudine during single and combination therapy, respectively. Total body clearance of zidovudine was not significantly altered by oxazepam (93 L/h vs. 109 L/h, p = 0.16). The mean pharmacokinetic parameters determined for a single 30-mg dose of oxazepam for oral clearance, apparent volume of distribution, and plasma half-life were 9.8 L/h, 65.7 L, and 5.1 h, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Intracellular glutathione levels in T cell subsets decrease in HIV-infected individuals.

The authors have shown previously that intracellular glutathione (GSH) plays an important role in the regulation of human immunodeficiency virus (HIV) transcription and replication in vitro, through modulation of signal transduction by inflammatory cytokines. Moreover, intracellular GSH levels are known to regulate T-lymphocyte function. In multiparameter FACS studies presented here, we show that relative GSH levels in CD4+ and CD8+ T cells from HIV+ individuals are significantly lower than in corresponding subsets from uninfected controls. These studies define the relative intracellular glutathione (GSH) levels in CD4+ T cells, CD8+ T cells, B cells, and monocytes from 134 HIV-infected individuals and 31 uninfected controls. The greatest decreases in intracellular GSH occur in subsets of T cells in individuals in the later stages of the HIV infection. In AIDS patients, GSH levels are 63% of normal in CD4+ T cells (p less than 0.0001) and are 62% of normal in CD8+ T cells (p less than 0.0001). Similarly, in AIDS-related complex (ARC) patients, GSH levels are 66% of normal in CD4+ T cells (p less than 0.003) and are 69% of normal in CD8+ T cells (p less than 0.003). These findings suggest that low intracellular GSH levels may be an important factor in HIV infection and in the resulting immunodeficiency.

CD20 expression is increased on B lymphocytes from HIV-infected individuals.

In studies presented here, we show that expression of the pan B cell marker CD20 is markedly increased on B lymphocytes from HIV-infected individuals and that this increase tends to be greater in individuals with more advanced disease. By using multiparameter FACS analyses to quantitate surface density of CD20 and intracellular glutathione (GSH) levels simultaneously, we further show that the distribution of intracellular glutathione (GSH) levels in B cells of HIV-infected individuals is more heterogeneous than in uninfected controls. Finally, we show that the intracellular GSH levels correlate with CD20 expression on a per-cell basis in all infected individuals. These findings suggest that CD20 expression, which can be precisely measured, may prove to be a useful surrogate marker for monitoring HIV infection.

Plasma viremia in human immunodeficiency virus infection: relationship to stage of disease and antiviral treatment.

Quantitative culture of human immunodeficiency virus (HIV) was performed on 121 plasma samples from 76 HIV-infected individuals to determine the sensitivity of the assay at different stages of disease and to measure the effect of antiviral therapy on plasma viremia. Plasma virus was detected in 49 of 76 (64%) of patients, primarily those with AIDS and AIDS-related complex (36 of 38) versus asymptomatic subjects (13 of 38) (p less than 0.001, chi 2). Similarly, plasma cultures were more often positive in patients with less than 250 CD4+ T cells per microliter (38 of 40) than in those with greater than 250 CD4+ T cells per microliter (11 of 36) (p less than 0.001, chi 2). Plasma virus cultures were also more likely to be positive in patients with detectable serum p24 antigen (24 of 26) than in those without detectable p24 antigen (25 of 50) (p = 0.0023, chi 2). An effect of zidovudine (ZDV) treatment on plasma viremia was seen in a comparison of treated and untreated patients with less than 250 CD4+ T cells per microliter. Geometric mean titers of plasma viremia from 16 patients treated with ZDV for more than 3 months were significantly lower than titers from 24 untreated patients (10(1.3) versus 10(2.1), p less than 0.05, Student's t test. A comparison of pre- and posttherapy titers in 33 patients receiving antiviral treatment showed that plasma virus was not detectable at either time in 17 patients; there was a fall in plasma virus titer in 12; and titers were unchanged or increased in 4. In patients with advanced disease, plasma viremia is a potential marker of antiviral drug activity.

Treatment of toxoplasmic encephalitis in patients with AIDS. A randomized trial comparing pyrimethamine plus clindamycin to pyrimethamine plus sulfadiazine. The California Collaborative Treatment Group.

OBJECTIVE: To compare pyrimethamine plus clindamycin (PC) to pyrimethamine plus sulfadiazine (PS) as a treatment for toxoplasmic encephalitis (TE) in patients with the acquired immunodeficiency syndrome (AIDS). DESIGN: Randomized, unblinded phase II, multicenter trial with provision for crossover for failure or intolerance of the assigned regimen. SETTING: University hospitals. PATIENTS: Eighty-four patients with presumptive TE were entered. Thirteen were excluded when they were found to have another diagnosis, and 12 were excluded because they did not meet entry criteria. The baseline characteristics in the remaining 26 patients randomized to PC and 33 randomized to PS were comparable. INTERVENTIONS: Patients were treated for 6 weeks with pyrimethamine and folinic acid plus either sulfadiazine or clindamycin. Clindamycin was given intravenously during the first 3 weeks. MEASUREMENTS AND MAIN RESULTS: There was a trend toward greater survival in patients randomized to PS (hazard ratio, 3.25; 95% CI, 0.63 to 16.8; P = 0.13), but most study deaths were not directly related to TE. In contrast, patients randomized to PC appeared more likely to achieve complete clinical (odds ratio, 0.67; CI, 0.2 to 1.97; P greater than 0.2) and radiologic responses (odds ratio, 0.28; CI, 0.08 to 0.96; P = 0.02). Multivariate analysis revealed drug effects to be largely independent of other variables. Similar efficacy of the treatments was also suggested by a hazard analysis of resolution of abnormal mental status, fever, and headache. Skin rash was the most common adverse event in both treatment arms. Because of toxicity, six patients randomized to PC and 11 patients randomized to PS had to switch to the alternate treatment, but only three were unable to complete therapy after crossover. CONCLUSIONS: The results of several end points of efficacy, taken together, suggest that the relative efficacy of PC approximately equals that of PS. PC appears to be an acceptable alternative in patients unable to tolerate PS.

Toxoplasma serology, parasitemia and antigenemia in patients at risk for toxoplasmic encephalitis.

In order to further characterize the pathogenesis of Toxoplasma gondii infection in patients with AIDS and AIDS-related complex (ARC), a cohort of HIV- and Toxoplasma-infected individuals were identified and prospectively followed. Four hundred and 10 HIV-infected individuals followed in the San Francisco General Hospital AIDS Clinic were screened for antibodies to Toxoplasma between November 1986 and November 1988. Of the 67 (16%) individuals seropositive for Toxoplasma antibodies, 33 (49%) were followed monthly for a mean duration of 7.5 months. One hundred and 11 follow-up blood samples were obtained in order to determine Toxoplasma serology and the incidence of parasitemia. In general, Toxoplasma immunoglobulin (Ig) G antibodies remained stable over time. Detection of Toxoplasma antigenemia and parasitemia was uniformly negative, including those specimens obtained from two individuals within 45 days of their developing toxoplasmic encephalitis.

Reduction in plasma human immunodeficiency virus ribonucleic acid after dideoxynucleoside therapy as determined by the polymerase chain reaction.

Cell-free HIV RNA in plasma was detected and quantitated after antiviral therapy by the polymerase chain reaction. RNA was extracted from plasma, reverse transcribed to cDNA, amplified by polymerase chain reaction, and quantitated by absorbance based on an enzyme-linked affinity assay. 72 HIV antibody-positive subjects had one plasma sample taken. 39 who were not receiving antiretroviral therapy at the time had a mean plasma HIV RNA copy number of 690 +/- 360 (mean +/- SEM) per 200 microliters of plasma, while 33 subjects who had been receiving zidovudine therapy for a minimum of 3 mo had a mean copy number of 134 +/- 219 (P less than 0.05). 27 additional HIV antibody-positive patients had two plasma samples taken before and 1 mo after initiating dideoxynucleoside therapy. Plasma HIV RNA copy number fell from 540 +/- 175 to 77 +/- 35 (P less than 0.05). Finally, nine of these subjects had two baseline samples obtained before initiating therapy and two posttreatment samples 1 and 2 mo after therapy was begun. Mean plasma RNA copy number declined from 794 +/- 274 to less than 40 (below the lower limit of sensitivity) after 1 mo of therapy, with suppression maintained after 2 mo of therapy. These results suggest that gene amplification can be used to detect and quantitate changes in plasma HIV RNA after dideoxynucleoside therapy. Plasma HIV polymerase chain reaction may be a more sensitive marker to monitor antiviral therapy, particularly in asymptomatic patients where measurement of p24 antigen or quantitative plasma cultures are negative.

Treatment of acute toxoplasmosis with intravenous clindamycin. The California Collaborative Treatment Group.

The interim results are presented of an ongoing large-scale, prospective, randomized study to determine the potential role of clindamycin in the treatment of toxoplasmic encephalitis. Patients were seropositive for Toxoplasma gondii antibodies and had clinical signs compatible with toxoplasmic encephalitis. Data was available on 33 patients, 15 of whom received pyrimethamine p.o./clindamycin i.v. and then p.o., and 18 of whom received pyrimethamine p.o./sulfadiazine p.o. The interim evaluation did not reveal a remarkable difference between the two regimens in the clinical or radiologic response. Adverse reactions to both regimens were common and frequently multiple, there being more adverse gastrointestinal reactions in patients on pyrimethamine/clindamycin and more adverse hematological reactions in those on pyrimethamine/sulfadiazine.