Factors associated with CD4 lymphocyte counts in HIV-negative Senegalese individuals

Per-pathogen virulence of HIV-1 subtypes A, C and D

HIV-1 subtypes differ in their clinical manifestations and the speed in which they spread. In particular, the frequency of subtype C is increasing relative to subtypes A and D. We investigate whether HIV-1 subtypes A, C and D differ in their per-pathogen virulence and to what extend this explains the difference in spread between these subtypes. We use data from the hormonal contraception and HIV-1 genital shedding and disease progression among women with primary HIV infection study. For each study participant, we determine the set-point viral load value, CD4⁺ T cell level after primary infection and CD4⁺ T cell decline. Based on both the CD4⁺ T cell count after primary infection and CD4⁺ T cell decline, we estimate the time until AIDS. We then obtain our newly introduced measure of virulence as the inverse of the estimated time until AIDS. After fitting a model to the measured virulence and set-point viral load values, we tested if this relation varies per subtype. We found that subtype C has a significantly higher per-pathogen virulence than subtype A. Based on an evolutionary model, we then hypothesize that differences in the primary length of infection period cause the observed variation in the speed of spread of the subtypes.

A Systematic Review and Meta-Analysis of Randomized Controlled Trials of the Effects of Vitamin D Supplementation on Children and Young Adults with HIV Infection

BACKGROUND

Children and young adults with HIV infection may exhibit vitamin D deficiency, which is harmful to bone health as well as the endocrine and immune systems.

OBJECTIVES

This study sought to investigate the effect of vitamin D supplementation on children and young adults with HIV infection.

METHODS

The PubMed, Embase, and Cochrane databases were searched. Randomized controlled trials that have evaluated the effects of vitamin D supplementation (ergocalciferol or cholecalciferol) at any dose or for any duration in children and young adults with HIV infection, aged 0-25 y, were included. A random-effects model was used, and the standardized mean difference (SMD) and 95% CI were calculated.

RESULTS

Ten trials, with 21 publications and 966 participants (mean age: 17.9 y), were included in the meta-analysis. The supplementation dose and the duration of the studies included ranged from 400 to 7000 IU/d and from 6 to 24 mo, respectively. Vitamin D supplementation was associated with a significantly higher serum 25(OH)D concentration at 12 mo (SMD: 1.14; 95% CI: 0.64, 1.65; P < 0.00001) compared with a placebo. No significant difference was observed in spine BMD (SMD: -0.09; 95% CI: -0.47, 0.3; P = 0.65) at 12 mo between these 2 groups. However, participants who received higher doses (1600-4000 IU/d) had significantly higher total BMD (SMD: 0.23; 95% CI: 0.02, 0.44; P = 0.03) and nonsignificantly higher spine BMD (SMD: 0.3; 95% CI: -0.02, 0.61; P = 0.07) at 12 mo compared with those who received standard doses (400-800 IU/d).

CONCLUSIONS

Vitamin D supplementation in children and young adults with HIV infection increases the serum 25(OH)D concentration. A relatively high daily dose of vitamin D (1600-4000 IU) improves total BMD at 12 mo and results in sufficient 25(OH)D concentrations.

Why does age at HIV infection correlate with set point viral load? An evolutionary hypothesis

BACKGROUND

Set-point viral load (SPVL) correlates with the age at which people acquire HIV. Although immunosenescence may seem like a parsimonious explanation for this, it does not easily explain the observation that the relationship between age and SPVL attenuates when accounting for source partner SPVL. Here we propose an alternative explanation that encompasses this latter finding: that decreasing risk of acquisition with older age generates a selection bottleneck that selects for more virulent strains with age.

METHODS

We adapted a previously published model of HIV transmission and evolution (EvoNetHIV), parameterized here for men who have sex with men (MSM). We conducted a series of simulation experiments that vary seven behavioral or clinical parameters that affect exposure risk as people age. We conducted regressions to determine the mean increase in SPVL per 10-year increase in seroconversion age, with and without source SPVL in the model.

RESULTS

All runs generated significant relationships between seroconversion age and SPVL when not including source SPVL. All saw attenuated relationships, most to near 0, with source SPVL included. Four of our behavioral measures (relational duration, age-related homophily, coital frequency, and mean age at relationship formation) had clear effects on this relationship, all in the hypothesized direction. Combining multiple forms of behavioral heterogeneity yielded an increase of 0.056 log10 copies/mL SPVL per 10-year increase in seroconversion age, nearly as large as that seen in two empirical studies of age-SPVL correlations in MSM.

CONCLUSION

The higher virulence of HIV among those infected later in life may be partly explained by a combination of selective bottlenecks and behavioral heterogeneity by age. Variation in the strength of this effect across populations may be in part due to different behavioral, epidemiological and clinical conditions, and not require assumptions about differences in patterns of immunosenescence among populations.

Hematologic reference intervals for healthy adult Saudis in Riyadh

BACKGROUND

Laboratory hematological tests are widely used in clinical practice to assess health and disease conditions. Reference ranges provided by laboratory reports are considered the most authoritative medical tools to assist in the decision-making phase. International standards institutes recommend that reference ranges be established for each region.

OBJECTIVES

Provide reference values of routine hematological parameters in Saudi adults according to age and gender.

DESIGN

Cross-sectional SETTING: Central province of Saudi Arabia.

PATIENTS AND METHODS

Apparently healthy Saudi adults were subjected to laboratory testing of routine hematological parameters (full blood count, hemostatic profile, and serum hematinics), after completing a detailed health medical questionnaire.

MAIN OUTCOME MEASURES

Hematological reference values based on the local population.

SAMPLE SIZE AND CHARACTERISTICS

637 after screening 827 potentially healthy Saudi adults with ages ranging from 15 to 65 years.

RESULTS

The reference values of routine hematological parameters for the full population and by gender are presented with 90% CI as the lower and upper limits. Reference ranges mostly differed from universal established ranges shown in textbooks.

CONCLUSION

The reference ranges of routine hematologic parameters for accurate assessment and appropriate management will help improve the routine clinical care of the adult Saudi population.

LIMITATIONS

Difficulty in assessing health status of participants, who could have subclinical illnesses not reflected in the evaluated blood measurement. Lack of ability to eliminate individuals who might be carriers for haemoglobinopathies. Studies with larger sample sizes from different areas of the country are required to achieve a more accurate representation of the whole Saudi population.

CONFLICT OF INTEREST

None.

Socio-Demographic, Economic and Clinical Predictors for HAART Adherence Competence in HIV-Positive Adults at Felege Hiwot Teaching and Specialized Hospital, North West Ethiopia

Background

Currently, around 36.7 million people in the world are living with HIV. Among these, 52% are living in sub-Saharan Africa. The main objective of this study was to identify socio-demographic economic and clinical factors associated with HAART adherence competence in successive visits among adult HIV patients after commencement of their treatment.

Methods

A retrospective cohort study design was conducted on a random sample of 792 treatment attendants. The samples were selected using stratified random samples technique considering their residence area as strata. Secondary data were used in this study. Structural equation modeling (SEM) was applied to identify predictors of HAART adherence competence over time.

Results

In this longitudinal study, factors affecting long-term HAART adherence competence in successive visits were identified. Among the predictors, marital status (mean = 3.97, variance = 0.6, p = 0.021), level of disclosure of the disease (mean = 6.24, variance = 0.29, p = 0.012), residence area (mean = 3.97, variance = 0.6, p = 0.021), level of education (mean = 2.04, variance= 0.81, p = 0.012), ownership of cell phone (mean = 2.99, variance = 0.68, p = 0.034), household income (mean = 6.37, variance = 0.53, p = 0.002), age of patients (mean = –2.78, variance = 56.64, p = 0.023), sex of patients (mean = –1.25, variance = 0.88, p = 0.036), weight (mean = –2.89, 42.36, p = 0.001), initial CD4 cell count (mean = 2.57, variance = 158.48, p = 0.015) and WHO stages (mean = 2.37, variance = 0.78, p = 0.026) were directly associated with retention of medication care. On the other hand, medication care was significantly and independently associated with longitudinal adherence competence.

Conclusion

The outcome variable in successive visits increased with the number of follow-up visits, but the rate of increase was different for different groups, such as urban and rural, and for those patients disclosing and not disclosing the disease to family members. An integrated health-related education should be given for non-adherent patients like rural residents, patients living without partners, patients with no cell phone and aged patients.

Factors related to baseline CD4 cell counts in HIV/AIDS patients: comparison of poisson, generalized poisson and negative binomial regression models

Objective

CD4 Lymphocyte Count (CD4) is a major predictor of HIV progression to AIDS. Exploring the factors affecting CD4 levels may assist healthcare staff and patients in management and monitoring of health cares. This retrospective cohort study aimed to explore factors associated with CD4 cell counts at the time of diagnosis in HIV patients using Poisson, Generalized Poisson, and Negative Binomial regression models.

Results

Out of 4402 HIV patients diagnosis in Iran from 1987 to 2016, 3030 (68.8%) were males, and the mean age was 34.8 ± 10.4 years. The results indicate that the Negative Binomial model outperformed the other models in terms of AIC, log-likelihood and RMSE criteria. In this model, factors include sex, age, clinical stage and Tuberculosis (TB) co-infection were significantly associated with CD4 count (P < 0.05).

Conclusion

Given the effect of age, sex, clinical stage and stage of HIV on CD4 count of the patients, adopting policies and strategies to increase awareness and encourage people to seek early HIV testing and care is advantageous.

A Rapid, Simple, and Low-Cost CD4 Cell Count Sensor Based on Blocking Immunochromatographic Strip System

The counting of CD4⁺ T lymphocytes (CD4 cells) is a critical test for evaluating the immune function of HIV-infected peoples and tumor patients. A rapid, simple, accurate, and low-cost CD4 cell counting method as a diagnostic tool is increasingly required in the clinic. We designed and developed a novel fluorescent immunochromatographic strips (ICS) system based on the blocking principle for counting CD4 cells. The strategy of this system is to count CD4 cells indirectly, by measuring the free CD4 antibodies that were not bound by CD4 cells. The fluorescent antibodies bound to CD4 cells were blocked at the filter pads, resulting in a decrease in fluorescence of free CD4 antibodies measured. The number of CD4 cells was inversely related to the fluorescence intensity. The CD4 count-ICSs exhibited a quasilinear response ( R² = 0.96) to logarithmic CD4 cell concentrations in PBMC samples in the range of 50-1000 cells/μL. In addition, the CD4 count-ICSs reliably quantified CD4 cells in whole blood samples, where the assay exhibited a linear correlation ( R² = 0.976) readout for CD4 cell concentrations ranging from 100 to 800 cells/μL. To validate the clinical applicability of this method, 54 blood samples were measured: the detection results showed a high correlation ( R² > 0.97) with the flow cytometry (FCM) analysis. The fluorescent ICSs can be used to count CD4 cells in blood samples, which have a high coincidence rate with FCM analysis; therefore, the CD4 count ICS system is an excellent candidate method for CD4 cell counting in resource-limited settings.

Association between CD4 T cell counts and the immune status among adult critically ill HIV-negative patients in intensive care units in Uganda

Background: Cluster of differentiation 4 (CD4) T cells play a central role in regulation of adaptive T cell-mediated immune responses. Low CD4 T cell counts are not routinely reported as a marker of immune deficiency among HIV-negative individuals, as is the norm among their HIV positive counterparts. Despite evidence of mortality rates as high as 40% among Ugandan critically ill HIV-negative patients, the use of CD4 T cell counts as a measure of the immune status has never been explored among this population. This study assessed the immune status of adult critically ill HIV-negative patients admitted to Ugandan intensive care units (ICUs) using CD4 T cell count as a surrogate marker. Methods: A multicentre prospective cohort was conducted between 1st August 2017 and 1st March 2018 at four Ugandan ICUs. A total of 130 critically ill HIV negative patients were consecutively enrolled into the study. Data on sociodemographics, clinical characteristics, critical illness scores, CD4 T cell counts were obtained at baseline and mortality at day 28. Results: The mean age of patients was 45± 18 years (mean±SD) and majority (60.8%) were male. After a 28-day follow up, 71 [54.6%, 95% CI (45.9-63.3)] were found to have CD4 counts less than 500 cells/mm³, which were not found to be significantly associated with mortality at day 28, OR (95%) 1 (0.4-2.4), p = 0.093. CD4 cell count receiver operator characteristic curve (ROC) area was 0.5195, comparable to APACHE II ROC area 0.5426 for predicting 24-hour mortality. Conclusions: CD4 T cell counts were generally low among HIV-negative critically ill patients. Low CD4 T cells did not predict ICU mortality at day 28. CD4 T cell counts were not found to be inferior to APACHE II score in predicting 24 hour ICU mortality.

A portable optical reader and wall projector towards enumeration of bio-conjugated beads or cells

Measurement of the height of a packed column of cells or beads, which can be direclty related to the number of cells or beads present in a chamber, is an important step in a number of diagnostic assays. For example, haematocrit measurements may rapidly identify anemia or polycthemia. Recently, user-friendly and cost-efficient Lab-on-a-Chip devices have been developed towards isolating and counting cell sub-populations for diagnostic purposes. In this work, we present a low-cost optical module for estimating the filling level of packed magnetic beads within a Lab-on-a-Chip device. The module is compatible with a previously introduced, disposable microfluidic chip for rapid determination of CD4+ cell counts. The device is a simple optical microscope module is manufactured by 3D printing. An objective lens directly interrogates the height of packed beads which are efficiently isolated on the finger-actuated chip. Optionally, an inexpensive, battery-powered Light Emitting Diode may project a shadow of the microfluidic chip at approximately 50-fold magnification onto a nearby surface. The reader is calibrated with the filling levels of known concentrations of paramagnetic beads within the finger actuated chip. Results in direct and projector mode are compared to measurements from a conventional, inverted white-light microscope. All three read-out methods indicate a maximum variation of 6.5% between methods.

T cell subset profile in healthy Zambian adults at the University Teaching Hospital

Introduction

Symptom-free human immunodeficiency virus antibody-negative Zambian adults (51 subjects, aged 20 to 62 years, 33.3% women and 66.7% men) were studied to establish T cell subset reference ranges.

Methods

We carried out across sectional study at the University Teaching Hospital, Lusaka. Blood samples were collected from healthy donor volunteers from hospital health care staff, between February and March 2015. Immunopheno typing was undertaken to characterize Tcell subsets using the markers CD3, CD4, CD8, α4β7, Ki67, CD25, CCR7, CD54RA, CD57, CD28, CD27 and HLA-DR.

Results

Among 51 volunteers, Women had significantly higher absolute CD4 count (median 1042; IQR 864, 1270) than in men (671; 545, 899) (p=0.003). Women also had more CD4 cells expressing homing, naïve, effector and effector memory T cell subsets compared to men. However, in the CD8 population, only the effector cells were significantly different with women expressing more than the males.

Conclusion

We provide early reference range for T cell subsets in Zambian adults and conclude that among the African women some T cell subsets are higher than men.

Emotional, physical and financial burdens of stigma against people living with HIV/AIDS in China

Numerous researches have shown pernicious effects of stigma against people living with HIV/AIDS (PLWHA). However, no available studies have reported these negative effects including emotional, physical to financial burdens to PLWHA. In the current study, we aim to explore different types of stigma (e.g., perceived, internalized and enacted) and the relevant consequences among PLWHA in China. A cross-sectional study was conducted from 2012 to 2013 in the Guangxi Autonomous Region in China. The validated Berger HIV Stigma Scale was used to measure various types of stigma. We employed a series of linear, logistic and polytomous regression models to assess the association between stigma and different consequences while accounting for potential confounders for each specific model. Of the total sample, 2987 PLWHA provided valid responses with 63% being male and having an average age of 42.9 years. Perceived, internalized and enacted HIV stigma were prevalent among participants, and resulted in various burdens with different magnitudes in their life contexts. Specially, PLWHA who reported higher perceived and internalized stigma were more likely to be imposed on emotional and physical burdens (p < .05). People who reported higher enacted stigma had heavier financial burden compared to their peers (p < .05). Our findings revealed that devastating consequences of HIV-related stigma in China. The prevalent stigmatizing attitudes have pushed PLWHA to the fringes of society and affected them at multiple aspects in their life context. We call for tailored efforts to overcome stigma and discrimination against PLWHA.

CD4 Cell Count: Declining Value for Antiretroviral Therapy Eligibility

Antiretroviral therapy (ART) policy for people living with human immunodeficiency virus (HIV) has historically been based on clinical indications, such as opportunistic infections and CD4 cell counts. Studies suggest that CD4 counts early in HIV infection do not predict relevant public health outcomes such as disease progression, mortality, and HIV transmission in people living with HIV. CD4 counts also vary widely within individuals and among populations, leading to imprecise measurements and arbitrary ART initiation. To capture the clinical and preventive benefits of treatment, the global HIV response now focuses on increasing HIV diagnosis and ART coverage. CD4 counts for ART initiation were necessary when medications were expensive and had severe side effects, and when the impact of early ART initiation was unclear. However, current evidence suggests that although CD4 counts may still play a role in guiding clinical care to start prophylaxis for opportunistic infections, CD4 counts should cease to be required for ART initiation.

Applying Novel Methods for Assessing Individual- and Neighborhood-Level Social and Psychosocial Environment Interactions with Genetic Factors in the Prediction of Depressive Symptoms in the Multi-Ethnic Study of Atherosclerosis

Complex illnesses, like depression, are thought to arise from the interplay between psychosocial stressors and genetic predispositions. Approaches that take into account both personal and neighborhood factors and that consider gene regions as well as individual SNPs may be necessary to capture these interactions across race and ethnic groups. We used novel gene-region based analysis methods [Sequence Kernel Association Test (SKAT) and meta-analysis (MetaSKAT), gene-environment set association test (GESAT)], as well as traditional linear models to identify gene region and SNP × psychosocial factor interactions at the individual- and neighborhood-level, across multiple race/ethnicities. Multiple regions identified in SKAT analyses showed evidence of a significant gene-region association with averaged depressive symptom scores across race/ethnicity (MetaSKAT p values <0.001). One region × neighborhood-environment interaction was significantly associated with averaged depressive symptom score across race/ethnicity after multiple testing correction (chr 18:21454070-21494070, Fisher's combined p value = 0.001). The examination of gene regions jointly with environmental factors measured at multiple levels (individuals and their contexts) may shed light on the etiology of depressive illness across race/ethnicities.

Establishment of Normal Reference Intervals for CD3(+), CD4(+), CD8(+), and CD4(+) to CD8(+) Ratio of T Lymphocytes in HIV Negative Adults from University of Gondar Hospital, North West Ethiopia

Background. Reference values for the CD3⁺, CD4⁺, CD8⁺, and CD4⁺ to CD8⁺ ratio T lymphocyte subsets are adopted from textbooks. But for appropriate diagnosis, treatment, and follow-up of patients, correct interpretations of the laboratory results from normal reference interval are mandatory. This study was, therefore, planned to establish normal reference interval for T lymphocytes subset count and CD4⁺ to CD8⁺ ratio. Methods. A cross-sectional study was conducted on apparently healthy adult individuals who visited voluntary counseling and HIV testing clinic Gondar University Hospital from April to May, 2013. Whole blood was analyzed using fluorescence-activated cell sorting (BD FACS, San Jose, CA) machine to enumerate the T-cell subpopulations. Results. Out of the total 320 study participants, 161 (50.3%) were men and 159 (49.7%) were women. The normal reference intervals were (655–2,823 cells/μL), (321–1,389 cells/μL), and (220–1,664 cells/μL) for CD3⁺, CD4⁺, and CD8⁺ T lymphocyte subsets, respectively, and CD4⁺ to CD8⁺ ratio was 0.5–2.5. Conclusion. The overall CD3⁺ T lymphocytes reference interval in the current study was wide; low CD4⁺ T lymphocytes, CD4 to CD8 ratio, and high CD8⁺ T lymphocytes values were observed.

Rapid, low-cost and instrument-free CD4+ cell counting for HIV diagnostics in resource-poor settings

We present a novel, user-friendly and widely autonomous point-of-care diagnostic to enable HIV monitoring in resource-poor regions where the current pandemic is most prevalent. To specifically isolate magnetically tagged CD4+ cells directly from patient blood, the low-cost and disposable microfluidic chip operates by dual-force CD4+ cell magnetophoresis; whereby the interplay of flow and magnetic fields governs the trajectory of target cells depending on whether the cell binds to a magnetic microbead. Instrument-free pumping is implemented by a finger-actuated elastic membrane; tagged beads are laterally deflected by a small and re-useable permanent magnet. The single-depth and monolithic microfluidic structure can easily be fabricated in a single casting step. After their magnetophoretic isolation from whole blood, estimation of CD4+ cell concentrations is then measured by bright-field inspection of the capture chamber. In addition, an optional fluorescence measurement can be used for confirmation of the bright-field result if required. On-chip CD4+ estimation produces a linear response over the full range of medically relevant CD4+ cell concentrations. Our technology combines high-efficiency capture (93.0 ± 3.3%) and cell enumeration.

Antiretroviral treatment outcomes amongst older adults in a large multicentre cohort in South Africa

INTRODUCTION

Increasing numbers of patients are starting antiretroviral treatment (ART) at advanced age or reaching advanced age while on ART. We compared baseline characteristics and ART outcomes of older adults (aged ≥55 years) vs. younger adults (aged 25-54 years) in routine care settings in South Africa.

METHODS

A multicentre cohort study of ART-naïve adults starting ART at 89 public sector facilities was conducted. Mortality, loss to follow-up (LTFU), immunological and virological outcomes until five years of ART were compared using competing-risks regression, generalised estimating equations and mixed-effects models.

RESULTS

4065 older adults and 86,006 younger adults were included. There were more men amongst older adults; 44.7% vs. 33.4%; RR = 1.34 (95% CI: 1.29-1.39). Mortality after starting ART was substantially higher amongst older adults, adjusted sub-hazard ratio (asHR) = 1.44 over 5 years (95% CI: 1.26-1.64), particularly for the period 7-60 months of treatment, asHR = 1.73 (95% CI: 1.44-2.10). LTFU was lower in older adults, asHR = 0.87 (95% CI: 0.78-0.97). Achievement of virological suppression was greater in older adults, adjusted odds ratio = 1.42 (95% CI: 1.23-1.64). The probabilities of viral rebound and confirmed virological failure were both lower in older adults, adjusted hazard ratios = 0.69 (95% CI: 0.56-0.85) and 0.64 (95% CI: 0.47-0.89), respectively. The rate of CD4 cell recovery (amongst patients with continuous viral suppression) was 25 cells/6 months of ART (95% CI: 17.3-33.2) lower in older adults.

CONCLUSIONS

Although older adults had better virological outcomes and reduced LTFU, their higher mortality and slower immunological recovery warrant consideration of age-specific ART initiation criteria and management strategies.

Population specific reference ranges of CD3, CD4 and CD8 lymphocyte subsets among healthy Kenyans

Background

The enumeration of absolute CD4 counts is of primary importance for many medical conditions especially HIV infection where therapeutic initiation depends on the count. These ranges tend to vary across populations. However, these ranges have not been comprehensively established in the Kenyan population. Therefore, this study aimed at establishing the reference ranges for the CD4 and CD8 T-lymphocytes in normal healthy individuals in Kenya.

Methods

A total of 315 individuals of the ages between 16 and 60 years old, in 5 different regions of the country, were recruited into the study. They were screened for diseases that potentially cause lymphocyte homeostasis perturbation. CD4/CD8 Counts were performed by use of a FACSCalibur flow cytometer (Becton-Dickinson, NJ) equipped with automated acquisition and analysis software. Results were analysed according to age, sex and region.

Results

Results were presented as means and ranges (in parenthesis) generated non parametrically as 2.5 and 97.5 percentiles as follows; In general population; CD3 1655 (614-2685 cells/μL ), CD4 920 (343-1493 cells/μL), and CD8 646 (187-1139 cells/μL), while according to sex, females; CD3 1787 (697-2841 cells/μL), CD4 1010 (422-1572 cells/μL), CD8 659 (187-1180 cells/μL); males; CD3 1610 (581-2641 cells/μL), CD4 889(320-1459 cells/μL) and CD8 644 (185-1140 cells/μL). The general reference ranges for CD4/CD8 ratios were as follows; general population 1.57(0.50-2.74), males 1.51(0.49-2.64) and females 1.69(0.55-2.95).

Conclusion

The lymphocyte reference ranges for the Kenyan population are fairly comparable to those established in other African populations. The ranges also differ appreciably from those established in Germany, Italy and Switzerland. Furthermore, the study reported significant differences in the ranges of different population clusters within Kenya, as well us between males and females.

Population-based CD4 counts in a rural area in South Africa with high HIV prevalence and high antiretroviral treatment coverage

Background

Little is known about the variability of CD4 counts in the general population of sub-Saharan Africa countries affected by the HIV epidemic. We investigated factors associated with CD4 counts in a rural area in South Africa with high HIV prevalence and high antiretroviral treatment (ART) coverage.

Methods

CD4 counts, health status, body mass index (BMI), demographic characteristics and HIV status were assessed in 4990 adult resident participants of a demographic surveillance in rural KwaZulu-Natal in South Africa; antiretroviral treatment duration was obtained from a linked clinical database. Multivariable regression analysis, overall and stratified by HIV status, was performed with CD4 count levels as outcome.

Results

Median CD4 counts were significantly higher in women than in men overall (714 vs. 630 cells/µl, p<0.0001), both in HIV-uninfected (833 vs. 683 cells/µl, p<0.0001) and HIV-infected adults (384.5 vs. 333 cells/µl, p<0.0001). In multivariable regression analysis, women had 19.4% (95% confidence interval (CI) 16.1–22.9) higher CD4 counts than men, controlling for age, HIV status, urban/rural residence, household wealth, education, BMI, self-reported tuberculosis, high blood pressure, other chronic illnesses and sample processing delay. At ART initiation, HIV-infected adults had 21.7% (95% CI 14.6–28.2) lower CD4 counts than treatment-naive individuals; CD4 counts were estimated to increase by 9.2% (95% CI 6.2–12.4) per year of treatment.

Conclusions

CD4 counts are primarily determined by sex in HIV-uninfected adults, and by sex, age and duration of antiretroviral treatment in HIV-infected adults. Lower CD4 counts at ART initiation in men could be a consequence of lower CD4 cell counts before HIV acquisition.

Women experience a better long-term immune recovery and a better survival on HAART in Lao People's Democratic Republic

Background

In April 2003, Médecins Sans Frontières launched an HIV/AIDS programme to provide free HAART to HIV-infected patients in Laos. Although HIV prevalence is estimated as low in this country, it has been increasing in the last years. This work reports the first results of an observational cohort study and it aims to identify the principal determinants of the CD4 cells evolution and to assess mortality among patients on HAART.

Methods

We performed a retrospective database analysis on patients initiated on HAART between 2003 and 2009 (CD4<200cells/μL or WHO stage 4). We excluded from the analysis patients who were less than 16 years old and pregnant women. To explore the determinants of the CD4 reconstitution, a linear mixed model was adjusted. To identify typical trajectories of the CD4 cells, a latent trajectory analysis was carried out. Finally, a Cox proportional-hazards model was used to reveal predictors of mortality on HAART including appointment delay greater than 1 day.

Results

A total of 1365 patients entered the programme and 913 (66.9%) received an HAART with a median CD4 of 49 cells/μL [IQR 15–148]. High baseline CD4 cell count and female gender were associated with a higher CD4 level over time. In addition, this gender difference increased over time. Two typical latent CD4 trajectories were revealed showing that 31% of women against 22% of men followed a high CD4 trajectory. In the long-term, women were more likely to attend appointments without delay. Mortality reached 6.2% (95% CI 4.8-8.0%) at 4 months and 9.1% (95% CI 7.3-11.3%) at 1 year. Female gender (HR=0.17, 95% CI 0.07-0.44) and high CD4 trajectory (HR=0.19, 95% CI 0.08-0.47) were independently associated with a lower death rate.

Conclusions

Patients who initiated HAART were severely immunocompromised yielding to a high early mortality. In the long-term on HAART, women achieved a better CD4 cells reconstitution than men and were less likely to die. This study highlights important differences between men and women regarding response to HAART and medical care, and questions men’s compliance to treatment.

Gender differences in notification rates, clinical forms and treatment outcome of tuberculosis patients under the RNTCP

Introduction:

An increased notification rate of tuberculosis (TB) in men is seen in the SAARC region. In India, the Revised National Tuberculosis Control Programme (RNTCP) detects nearly three times more male than female TB patients. Gender differences have also been reported in the clinical forms of tuberculous disease and in treatment adherence and cure rates in patients undergoing treatment for tuberculosis. The present study was undertaken to find out the sex differences in the notification rates and treatment outcomes of TB patients registered under the RNTCP in a rural tuberculosis unit (TU) in West Bengal.

Materials and Methods:

A retrospective record-based study was carried out among a total of 3605 cases registered under the RNTCP between January 1999 and June 2005. Notification rates of TB, clinical forms of TB and disease treatment outcomes recorded in the registers were analyzed based on genders. Outcomes were defined in accordance with the standard RNTCP definitions. The Z-test for proportion (for comparing differences in proportions), Student t-test (for comparing mean), and χ² test (to see association) were performed for statistical analysis.

Results:

Among the total of 3605 patients, 2498 (69.3%) were male and 1107 (30.7%) were female with a male female ratio of 2.25:1. In patients less than 20 years of age, the notification rates among males and females were similar. In the other age groups, males were more likely to be notified compared to females and the difference was statistically significant. While new smear positive and retreatment cases were significantly more than in males, among females, new smear negative and new extrapulmonary cases were significantly higher. Among the new smear positive patients 89.4% of females were cured compared to 85.8% of males which was again significant statistically (Z=1.70, P<0.05). Male patients outnumbered females in all the unfavorable outcomes like death, failure, and default although none of the differences were statistically significant (P>0.05).

Conclusion:

The present study demonstrates a gender difference in the notification rates, clinical presentations and treatment outcomes of patients with tuberculosis. Integrated research is necessary to find the reasons for these differences. Such studies will be helpful in improving the efficacy of the RNTCP.

Immune interference in the setting of same-day administration of two similar inactivated alphavirus vaccines: eastern equine and western equine encephalitis

We compared the effect on primary vaccination plaque-reduction neutralization 80% titers (PRNT80) responses of same-day administration (at different injection sites) of two similar investigational inactivated alphavirus vaccines, eastern equine encephalitis (EEE) vaccine (TSI-GSD 104) and western equine encephalitis (WEE) vaccine (TSI-GSD 210) to separate administration. Overall, primary response rate for EEE vaccine was 524/796 (66%) and overall primary response rate for WEE vaccine was 291/695 (42%). EEE vaccine same-day administration yielded a 59% response rate and a responder geometric mean titer (GMT)=89 while separate administration yielded a response rate of 69% and a responder GMT=119. WEE vaccine same-day administration yielded a 30% response rate and a responder GMT=53 while separate administration yielded a response rate of 54% and a responder GMT=79. EEE response rates for same-day administration (group A) vs. non-same-day administration (group B) were significantly affected by gender. A logistic regression model predicting response to EEE comparing group B to group A for females yielded an OR=4.10 (95% CL 1.97-8.55; p=.0002) and for males yielded an OR=1.25 (95% CL 0.76-2.07; p=.3768). WEE response rates for same-day administration vs. non-same-day administration were independent of gender. A logistic regression model predicting response to WEE comparing group B to group A yielded an OR=2.14 (95% CL 1.22-3.73; p=.0077). We report immune interference occurring with same-day administration of two completely separate formalin inactivated viral vaccines in humans. These findings combined with the findings of others regarding immune interference would argue for a renewed emphasis on studying the immunological mechanisms of induction of inactivated viral vaccine protection.

CD4- and CD3-T lymphocyte reference values of immunocompetent urban and rural subjects in an African nation

Studies on the reference values of CD4 and CD3 T cells in healthy individuals have continued to gain significance because of the importance of these immunological markers in the initiation of combination antiretroviral therapy (cART). The aim of the present study was to determine and compare the reference values of CD4 and CD3 T cells in urban and rural Nigerians who were human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) negative. After ethical clearance and informed consent, 1123 subjects who met the inclusion criteria [mean age = 24.4 (± 11.2) years] were recruited in this study. Blood samples were analysed using the BD FACScount cytometer according to the manufacturer's instructions. Of the overall 1123 subjects, reference means of CD4, CD3 and CD4/CD3 ratio were 1030 ± 367, 1757 ± 609 cells/μl and 0.59 ± 0.08, respectively. Five hundred and fifty-one (49.1%) were an urban population with the mean CD4, CD3 and CD4/CD3 T cell ratio of 1032 ± 369, 1761 ± 612 cells/μl and 0.59 (±0.08), respectively. The remaining 572 (50.9%) were of a rural population with the mean CD4, CD3 and CD4/CD3 T cell ratio of 1028 ± 459, 1753 ± 958 cells/μl and 0.59 ± 0.13, respectively. Subjects with higher CD4 and CD3 T cells were more likely to be female than male (P < 0.05). There was no significant difference between the T cell values of the two populations (P > 0.05). Our findings provide new insight in the CD4 and CD3 T cell reference values of Nigerians.

CD4+ T lymphocyte reference values of immunocompetent subjects in an African university

CD4(+) T cells play critical roles in the immune system and, being primary targets of HIV infection, they are used to measure disease progression and response to combination antiretroviral therapy (cART), alongside other parameters, in HIV/AIDS patients. The aim of this study was to determine the reference values of CD4(+) T cells in a student population that was HIV, hepatitis B virus (HBV) and hepatitis C virus (HCV) negative. After ethical clearance and informed consent, 500 subjects (mean age = 26 years) were recruited, of whom 56 (11.2%) had HIV, HBV or HCV and were excluded. Blood samples were collected from the remaining 444 subjects into vacutainer tubes and analysed using the BD FACScount cytometer according to the manufacturer's instructions. Of the 444 subjects, 266 (59.9%) were male and 178 (40.1%) were female. The mean (± standard deviation) CD4(+) T cell count was 987 cells/µL (± 336). The mean counts among males and females were 957 cells/µL (± 306) and 991 cells/µL (± 340), respectively. Values of CD4(+) T cells ranged from 651 cells/µL to 1705 cells/µL. Subjects with higher CD4(+) T Cells were more likely to be female than male. There was no direct correlation between CD4(+) T cell values and age of the participants. Our findings offer the first insight into the CD4(+) T cell reference values of a Nigerian student population and provide useful data that will guide future cART decisions and other immune-based therapies.

Nevirapine-associated hepatotoxicity was not predicted by CD4 count ≥250 cells/μL among women in Zambia, Thailand and Kenya

OBJECTIVE

The aim of the study was to determine risk factors for developing severe hepatotoxicity (grade 3 or 4 hepatotoxicity) and rash-associated hepatotoxicity (rash with ≥ grade 2 hepatotoxicity) among women initiating nevirapine-based antiretroviral therapy (ART).

METHODS

The Non-Nucleoside Reverse Transcriptase Inhibitor Response Study was a prospective cohort study carried out in Zambia, Thailand and Kenya. Between May 2005 and January 2007, we enrolled antiretroviral-naïve HIV-infected women initiating nevirapine-based ART. At enrollment and at weeks 2, 4, 8, 16 and 24, participants had serum alanine transferase (ALT) and aspartate transaminase (AST) measured and were evaluated clinically for hepatitis and rash.

RESULTS

Nevirapine-based ART was initiated in 820 women and baseline ALT or AST results were abnormal (≥ grade 1) in 113 (14%) women. After initiating nevirapine-based ART, severe hepatotoxicity occurred in 41 (5%) women and rash-associated hepatotoxicity occurred in 27 (3%) women. In a multivariate logistic regression model, severe hepatotoxicity and rash-associated hepatotoxicity were both associated with baseline abnormal (≥ grade 1) ALT or AST results, but not with a baseline CD4 cell count ≥250 cells/μL. Three participants (0.4%) died with symptoms suggestive of fatal hepatotoxicity; all three women had baseline CD4 count <100 cells/μL and were receiving anti-tuberculosis therapy.

CONCLUSION

Among women taking nevirapine-based ART, severe hepatotoxicity and rash-associated hepatotoxicity were predicted by abnormal baseline ALT or AST results, but not by a CD4 count ≥250 cells/μL. In resource-limited settings where transaminase testing is available, testing should focus on early time-points and on women with abnormal baseline ALT or AST results.

Difference in absolute CD4+ count according to CD4 percentage between Asian and Caucasian HIV-infected patients

We compared the absolute CD4+ count, at different CD4+ percentages (CD4%), between Asian (n=442) and Caucasian (n=674) untreated HIV-infected individuals, using linear regression methods. At any given CD4%, Asians had lower CD4+ count than Caucasians (p=0.001). The difference varied from 38.9 cells/mm(3) (95% CI: 3.3-74.5 cells/mm(3)) at CD4% of 15% to 108.7 cells/mm(3) (95% CI: 42.5-174.9 cells/mm(3)) at CD4% of 40%. The impact of these differences on prognosis is uncertain, but it may be that the prognostic thresholds for CD4+ count used in Caucasian populations are inappropriate in Asian populations.

Reference ranges for the clinical laboratory derived from a rural population in Kericho, Kenya

The conduct of Phase I/II HIV vaccine trials internationally necessitates the development of region-specific clinical reference ranges for trial enrollment and participant monitoring. A population based cohort of adults in Kericho, Kenya, a potential vaccine trial site, allowed development of clinical laboratory reference ranges. Lymphocyte immunophenotyping was performed on 1293 HIV seronegative study participants. Hematology and clinical chemistry were performed on up to 1541 cohort enrollees. The ratio of males to females was 1.9:1. Means, medians and 95% reference ranges were calculated and compared with those from other nations. The median CD4+ T cell count for the group was 810 cells/microl. There were significant gender differences for both red and white blood cell parameters. Kenyan subjects had lower median hemoglobin concentrations (9.5 g/dL; range 6.7-11.1) and neutrophil counts (1850 cells/microl; range 914-4715) compared to North Americans. Kenyan clinical chemistry reference ranges were comparable to those from the USA, with the exception of the upper limits for bilirubin and blood urea nitrogen, which were 2.3-fold higher and 1.5-fold lower, respectively. This study is the first to assess clinical reference ranges for a highland community in Kenya and highlights the need to define clinical laboratory ranges from the national community not only for clinical research but also care and treatment.

Reference ranges for the clinical laboratory derived from a rural population in Kericho, Kenya

The conduct of Phase I/II HIV vaccine trials internationally necessitates the development of region-specific clinical reference ranges for trial enrolment and participant monitoring. A population based cohort of adults in Kericho, Kenya, a potential vaccine trial site, allowed development of clinical laboratory reference ranges. Lymphocyte immunophenotyping was performed on 1293 HIV seronegative study participants. Hematology and clinical chemistry were performed on up to 1541 cohort enrollees. The ratio of males to females was 1.9∶1. Means, medians and 95% reference ranges were calculated and compared with those from other nations. The median CD4+ T cell count for the group was 810 cells/µl. There were significant gender differences for both red and white blood cell parameters. Kenyan subjects had lower median hemoglobin concentrations (9.5 g/dL; range 6.7–11.1) and neutrophil counts (1850 cells/µl; range 914–4715) compared to North Americans. Kenyan clinical chemistry reference ranges were comparable to those from the USA, with the exception of the upper limits for bilirubin and blood urea nitrogen, which were 2.3-fold higher and 1.5-fold lower, respectively. This study is the first to assess clinical reference ranges for a highland community in Kenya and highlights the need to define clinical laboratory ranges from the national community not only for clinical research but also care and treatment.