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Changes in D-dimer after initiation of antiretroviral therapy in adults living with HIV in Kenya
Background
Increased coagulation biomarkers are associated with poor outcomes among people living with HIV (PLHIV). There are few data available from African cohorts demonstrating the effect of antiretroviral therapy (ART) on coagulation biomarkers.
Methods
From March 2014 to October 2014, ART-naïve PLHIV initiating non-nucleoside reverse transcriptase inhibitor-based ART were recruited from seven clinics in western Kenya and followed for up to 12 months. Demographics, clinical history and blood specimens were collected. Logistic regression models adjusted for intrasite clustering examined associations between HIV viral load and D-Dimer at baseline. Mixed linear effects models were used to estimate mean change from baseline to 6 months overall, and by baseline viral load, sex and TB status at enrollment. Mean change in D-dimer at 6 months is reported on the log10 scale and as percentage change from baseline.
Results
Among 611 PLHIV enrolled, 66% were female, median age was 34 years (interquartile range (IQR) 29–43 years), 31 (5%) participants had tuberculosis and median viral load was 113,500 copies/mL (IQR: 23,600-399,000). At baseline, 311 (50.9%) PLHIV had elevated D-dimer (> 500 ng/mL) and median D-dimer was 516.4 ng/mL (IQR: 302.7–926.6) (log baseline D-dimer: 2.7, IQR: 2.5–3.0). Higher baseline D-dimer was significantly associated with higher viral load (p 6.0 copies/mL (− 91.1, 95%CI −136.7, − 54.2; p < 0.01).
Conclusions
In this large Kenyan cohort of PLHIV, women, those with tuberculosis and higher viral load had elevated baseline D-dimer. ART initiation and viral load suppression among ART-naïve PLHIV in Kenya were associated with significant decrease in D-dimer at 6 months in this large African cohort
Evaluation of a Quantitative Real-Time PCR Assay to Measure HIV-Specific Mucosal CD8+ T Cell Responses in the Cervix
Several candidate HIV vaccines aim to induce virus-specific cellular immunity particularly in the genital tract, typically the initial site of HIV acquisition. However, standardized and sensitive methods for evaluating HIV-specific immune responses at the genital level are lacking. Therefore we evaluated real-time quantitative PCR (qPCR) as a potential platform to measure these responses. β-Actin and GAPDH were identified as the most stable housekeeping reference genes in peripheral blood mononuclear cells (PBMCs) and cervical mononuclear cells (CMCs) respectively and were used for normalizing transcript mRNA expression. HIV-specific cellular T cell immune responses to a pool of optimized CD8+ HIV epitopes (HIV epitope pool) and Staphylococcal enterotoxin B (SEB) superantigen control were assayed in HIV infected PBMC by qPCR, with parallel assessment of cytokine protein production. Peak HIV-specific mRNA expression of IFNγ, IL-2 and TNFα occurred after 3, 5 and 12 hours respectively. PBMCs were titrated to cervical appropriate cell numbers to determine minimum required assay input cell numbers; qPCR retained sensitivity with input of at least 2.5×104 PBMCs. This optimized qPCR assay was then used to assess HIV-specific cellular T cell responses in cytobrush-derived cervical T cells from HIV positive individuals. SEB induced IFNγ mRNA transcription was detected in CMCs and correlated positively with IFNγ protein production. However, qPCR was unable to detect HIV-induced cytokine mRNA production in the cervix of HIV-infected women despite robust detection of gene induction in PBMCs. In conclusion, although qPCR can be used to measure ex vivo cellular immune responses to HIV in blood, HIV-specific responses in the cervix may fall below the threshold of qPCR detection. Nonetheless, this platform may have a potential role in measuring mitogen-induced immune responses in the genital tract
Does antiretroviral therapy initiation increase sexual risk taking in Kenyan female sex workers? A retrospective case–control study
Self-reported drunkenness among adolescents in four sub-Saharan African countries: associations with adverse childhood experiences
<p>Abstract</p> <p>Background</p> <p>Consumption of alcohol is associated with acute and chronic adverse health outcomes. There is a paucity of studies that explore the determinants of alcohol use among adolescents in sub-Saharan Africa and, in particular, that examine the effects of adverse childhood experiences on alcohol use.</p> <p>Methods</p> <p>The paper draws on nationally-representative data from 9,819 adolescents aged 12-19 years from Burkina Faso, Ghana, Malawi, and Uganda. Logistic regression models were employed to identify correlates of self-reported past-year drunkenness. Exposure to four adverse childhood experiences comprised the primary independent variables: living in a food-insecure household, living with a problem drinker, having been physically abused, and having been coerced into having sex. We controlled for age, religiosity, current schooling status, the household head's sex, living arrangements, place of residence, marital status, and country of survey. All analyses were conducted separately for males and females.</p> <p>Results</p> <p>At the bivariate level, all independent variables (except for coerced sex among males) were associated with the outcome variable. Overall, 9% of adolescents reported that they had been drunk in the 12 months preceding the survey. In general, respondents who had experienced an adverse event during childhood were more likely to report drunkenness. In the multivariate analysis, only two adverse childhood events emerged as significant predictors of self-reported past-year drunkenness among males: living in a household with a problem drinker before age 10, and being physically abused before age 10. For females, exposure to family-alcoholism, experience of physical abuse, and coerced sex increased the likelihood of reporting drunkenness in the last 12 months. The association between adverse events and reported drunkenness was more pronounced for females. For both males and females there was a graded relationship between the number of adverse events experienced and the proportion reporting drunkenness.</p> <p>Conclusions</p> <p>We find an association between experience of adverse childhood events and drunkenness among adolescents in four sub-Saharan African countries. The complex impacts of adverse childhood experiences on young people's development and behavior may have an important bearing on the effectiveness of interventions geared at reducing alcohol dependence among the youth.</p
Evaluating the Interaction of HIV and the Immune System in Mucosal Tissues
90% of Human Immunodeficiency Virus (HIV) infections are acquired across the genital or gastrointestinal mucosa, and infection leads to profound depletion of CD4+ lymphocytes. Antiretroviral therapy can restore blood CD4+ T cells. However, immune dysfunction and defects in mucosal antimicrobial defence persist. Some CD4+ T-subsets, particularly antimicrobial Th17 cells, show enhanced susceptibility to HIV infection and are also preferentially depleted in the course of HIV infection; the latter may allow microbial translocation into the bloodstream. Genital infections have been shown to have direct mucosal immune effects and to increase susceptibility to HIV; however, the effect of systemic infections, such as Malaria (which is holo-endemic in some HIV prevalent regions) is unknown. Understanding the relationship between HIV, highly susceptible immune cells, immune activation and malaria infection on mucosal tissues has been the main focus of my thesis.
In HIV-infected individuals, I explored whether HIV antiretroviral therapy restores gut Th17 populations and improves gut antimicrobial defences. Therapy restored gut Th17 populations in some, but not all individuals, but antimicrobial defence remained impaired. I then piloted a novel mucosal-optimized PCR assay to measure cervical immune gene responses, as standard mucosal assays are inadequate. I succeeded in measuring mitogen-induced, but not HIV-specific, cervical immune responses in HIV-infected individuals. Next, using this PCR platform I examined mitogen-induced cervical immune responses in individuals demonstrating reduced susceptibility to HIV, and found that they had reduced production of both Th17-associated and pro-inflammatory cytokines from cervical cells. Finally, in a murine model I found that malaria caused genital and gastrointestinal mucosal immune activation, and increased both the expression of mucosal HIV susceptibility immune markers, and mucosal T cell immune activation.
In summary, insufficient gastrointestinal Th17 cells restoration does not underlie persistent mucosal immune activation and microbial translocation in HIV-infected people on therapy. A reduced frequency of highly susceptible Th17 cells in the cervix of HIV-exposed but uninfected individuals was identified as a correlate of reduced HIV susceptibility. Malaria, a common systemic infection in HIV-endemic countries, may enhance susceptibility to HIV through increasing putative immune markers of HIV susceptibility and immune activation in potential mucosal sites of HIV exposure.Ph
Lay health worker experiences administering a multi-level combination intervention to improve PMTCT retention
Abstract Background The recent scale-up of prevention of mother-to-child transmission of HIV (PMTCT) services has rapidly accelerated antiretroviral therapy (ART) uptake among pregnant and postpartum women in sub-Saharan Africa. The Mother and Infant Retention for Health (MIR4Health) study evaluates the impact of a combination intervention administered by trained lay health workers to decrease attrition among HIV-positive women initiating PMTCT services and their infants through 6 months postpartum. Methods This was a qualitative study nested within the MIR4Health trial. MIR4Health was conducted at 10 health facilities in Nyanza, Kenya from September 2013 to September 2015. The trial intervention addressed behavioral, social, and structural barriers to PMTCT retention and included: appointment reminders via text and phone calls, follow-up and tracking for missed clinic visits, PMTCT health education at home visits and during clinic visits, and retention and adherence support and counseling. All interventions were administered by lay health workers. We describe results of a nested small qualitative inquiry which conducted two focus groups to assess the experiences and perceptions of lay health workers administering the interventions. Discussions were recorded and simultaneously transcribed and translated into English. Data were analyzed using framework analysis approach. Results Study findings show lay health workers played a critical role supporting mothers in PMTCT services across a range of behavioral, social, and structural domains, including improved communication and contact, health education, peer support, and patient advocacy and assistance. Findings also identified barriers to the uptake and implementation of the interventions, such as concerns about privacy and stigma, and the limitations of the healthcare system including healthcare worker attitudes. Overall, study findings indicate that lay health workers found the interventions to be feasible, acceptable, and well received by clients. Conclusions Lay health workers played a fundamental role in supporting mothers engaged in PMTCT services and provided valuable feedback on the implementation of PMTCT interventions. Future interventions must include strategies to ensure client privacy, decrease stigma within communities, and address the practical limitations of health systems. This study adds important insight to the growing body of research on lay health worker experiences in HIV and PMTCT care. Trial registration Clinicaltrials.gov NCT01962220
Identifying the Gaps: An Assessment of Nurses' Training, Competency, and Practice in HIV Care and Treatment in Kenya
Given the burden of HIV and the critical shortage of health workers in Kenya, in 2011 the National AIDS and STI Control Program recommended shifting HIV care and treatment tasks to nurses in settings without physicians and clinical officers in order to decentralize and scale-up HIV services. In September 2013, ICAP at Columbia University conducted a survey with nurses in four health facilities in eastern Kenya to assess preparedness for task shifting. Findings indicated gaps in nurses' training, perceived competency, and practice in HIV care and treatment. Further investment in nurse capacity building is needed to bridge the gaps and prepare more nurses to provide high-quality, comprehensive HIV care and treatment services to curb the epidemic in Kenya