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27 result(s) for "Tempelman, Hugo A."
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Evaluation of a commercial SARS-CoV-2 multiplex PCR genotyping assay for variant identification in resource-scarce settings
The rapid emergence and spread of numerous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants across the globe underscores the crucial need for continuous SARS-CoV-2 surveillance to ensure that potentially more pathogenic variants are detected early and contained. Whole genome sequencing (WGS) is currently the gold standard for COVID-19 surveillance; however, it remains cost-prohibitive and requires specialized technical skills. To increase surveillance capacity, especially in resource-scarce settings, supplementary methods that are cost- and time-effective are needed. Real-time multiplex PCR genotyping assays offer an economical and fast solution for screening circulating and emerging variants while simultaneously complementing existing WGS approaches. In this study we evaluated the Allplex TM SARS-CoV-2 Variants II multiplex real-time PCR genotyping assay, Seegene (South Korea), and implemented it in retrospectively characterizing circulating SARS-CoV-2 variants in a rural South African setting between April and October 2021, prior to the emergence of the Omicron variant in South Africa. The Allplex TM SARS-CoV-2 Variants II real-time PCR assay demonstrated perfect concordance with whole-genome sequencing in detecting Beta and Delta variants and exhibited high specificity, sensitivity and reproducibility. Implementation of the assay in characterization of SARS-CoV-2 variants between April and October 2021 in a rural South African setting revealed a rapid shift from the Beta to the Delta variant between April and June. All specimens successfully genotyped in April were Beta variants and the Delta variant was not detected until May. By June, 78% of samples genotyped were Delta variants and in July >95% of all genotyped samples were Delta variants. The Delta variant continued to predominate through to the end of our analysis in October 2021. Taken together, a commercial SARS-CoV-2 variant genotyping assay detected the rapid rate at which the Delta variant displaced the Beta variant in Limpopo, an under-monitored province in South Africa. Such assays provide a quick and cost-effective method of monitoring circulating variants and should be used to complement genomic sequencing for COVID-19 surveillance especially in resource-scarce settings.
Virological suppression and clinical management in response to viremia in South African HIV treatment program: A multicenter cohort study
Uptake of antiretroviral treatment (ART) is expanding rapidly in low- and middle-income countries (LMIC). Monitoring of virological suppression is recommended at 6 months of treatment and annually thereafter. In case of confirmed virological failure, a switch to second-line ART is indicated. There is a paucity of data on virological suppression and clinical management of patients experiencing viremia in clinical practice in LMIC. We report a large-scale multicenter assessment of virological suppression over time and management of viremia under programmatic conditions. Linked medical record and laboratory source data from adult patients on first-line ART at 52 South African centers between 1 January 2007 and 1 May 2018 were studied. Virological suppression, switch to second-line ART, death, and loss to follow-up were analyzed. Multistate models and Cox proportional hazard models were used to assess suppression over time and predictors of treatment outcomes. A total of 104,719 patients were included. Patients were predominantly female (67.6%). Median age was 35.7 years (interquartile range [IQR]: 29.9-43.0). In on-treatment analysis, suppression below 1,000 copies/mL was 89.0% at month 12 and 90.4% at month 72. Suppression below 50 copies/mL was 73.1% at month 12 and 77.5% at month 72. Intention-to-treat suppression was 75.0% and 64.3% below 1,000 and 50 copies/mL at month 72, respectively. Viremia occurred in 19.8% (20,766/104,719) of patients during a median follow-up of 152 (IQR: 61-265) weeks. Being male and below 35 years of age and having a CD4 count below 200 cells/μL prior to start of ART were risk factors for viremia. After detection of viremia, confirmatory testing took 29 weeks (IQR: 16-54). Viral resuppression to below 1,000 copies/mL without switch of ART occurred frequently (45.6%; 6,030/13,210) but was associated with renewed viral rebound and switch. Of patients with confirmed failure who remained in care, only 41.5% (1,872/4,510) were switched. The median time to switch was 68 weeks (IQR: 35-127), resulting in 12,325 person-years spent with a viral load above 1,000 copies/mL. Limitations of this study include potential missing data, which is in part addressed by the use of cross-matched laboratory source data, and the possibility of unmeasured confounding. In this study, 90% virological suppression below the threshold of 1,000 copies/mL was observed in on-treatment analysis. However, this target was not met at the 50-copies/mL threshold or in intention-to-treat analysis. Clinical management in response to viremia was profoundly delayed, prolonging the duration of viremia and potential for transmission. Diagnostic tools to establish the cause of viremia are urgently needed to accelerate clinical decision-making.
The association of HIV status and depressive symptoms in the Ndlovu Cohort study
HIV majorly contributes to the disease burden in South Africa. Depressive symptoms are common in people living with HIV (PLHIV). Few studies compared depressive symptoms between PLHIV and those without HIV. The aim of the study was to examine the association of HIV status and depressive symptoms. Moreover, the study aimed to explore the comparison between HIV-negative participants and the different HIV-positive sub-groups regarding their depressive symptoms. A cross-sectional analysis was conducted among PLHIV and HIV-negative participants in rural South Africa, using the baseline data of the Ndlovu Cohort study. Data was collected on demographics, socioeconomic status, and depressive symptoms using the PHQ-9 questionnaire. A score of 10 and above indicated depressive symptoms. Logistic regression analysis on the relationship between HIV status and depressive symptoms was used while adjusting for age, sex, level of education, employment status, income, and ever smoking. The study included 1,927 participants; 46% were PLHIV and 239 (12.5%) had depressive symptoms. PLHIV were more likely to have depressive symptoms than HIV-negative participants (OR 1.34, 95% CI 1.01–1.77). This association was not statistically significant after adjusting for confounders (OR 1.22, 95% CI 0.92–1.63). Compared to HIV-negative participants, ART (antiretroviral treatment) naïve participants had statistically significant higher odds of depressive symptoms (OR 1.84, 95% CI 1.20–2.78). This association remained after adjusting for confounders (OR 1.72, 95% CI 1.11–2.61). There was no statistically significant difference in depressive symptoms between HIV-negative participants and those on ART, regardless of treatment regimen. In general, higher odds of depressive symptoms in ART-naïve PLHIV could reflect poor coping with diagnosis of HIV. Future research to investigate the relation between ART regimen and depressive symptoms, to establish causality and to identify changes over time, is warranted.
Predictors of Treatment Adherence and Virological Failure Among People Living with HIV Receiving Antiretroviral Therapy in a South African Rural Community: A Sub-study of the ITREMA Randomised Clinical Trial
A large proportion of people living with HIV (PLHIV) in sub-Saharan Africa reside in rural areas. Knowledge of enablers and barriers of adherence to antiretroviral treatment (ART) in these populations is limited. We conducted a cohort study of 501 adult PLHIV on ART at a rural South African treatment facility as a sub-study of a clinical trial (ClinicalTrials.gov NCT03357588). Socio-economic, psychosocial and behavioral characteristics were assessed as covariates of self-reported adherence difficulties, suboptimal pill count adherence and virological failure during 96 weeks of follow-up. Male gender was an independent risk factor for all outcomes. Food insecurity was associated with virological failure in males. Depressive symptoms were independently associated with virological failure in both males and females. Household income and task-oriented coping score were protective against suboptimal pill-count adherence. These results underscore the impact of low household income, food insecurity and depression on outcomes of ART in rural settings and confirm other previously described risk factors. Recognition of these factors and targeted adherence support strategies may improve patient health and treatment outcomes.
The association between HIV infection and pulmonary function in a rural African population
HIV infection has been associated with an impaired lung function in high-income countries, but the association between HIV infection and pulmonary function in Sub-Saharan Africa remains unclear. This study aims to investigate the relation between HIV infection and pulmonary function in a rural African population. A cross-sectional study was conducted among HIV-positive and HIV-negative adults in a rural area in South Africa, as part of the Ndlovu Cohort Study. A respiratory questionnaire and post-bronchodilator spirometry were performed. Multivariable regression analysis was used to investigate whether HIV was independently associated with a decrease in post-bronchodilator FEV1/FVC ratio considering age, sex, body mass index, respiratory risk factors and a history of a pulmonary infection (tuberculosis (TB) or a pneumonia). Possible mediation by a history of pulmonary infection was tested by removing this variable from the final model. Two hundred and one consecutive participants were enrolled in the study in 2016, 84 (41.8%) were HIV-positive (82.1% on ART). The median age was 38 (IQR 29-51) years. Following multivariable analysis HIV was not significantly associated to a decline in post-bronchodilator FEV1/FVC ratio (β -0.017, p 0.18). However, upon removal of a history of a pulmonary infection from the final model HIV was significantly related to post-bronchodilator FEV1/FVC ratio, β -0.026, p 0.03. Pulmonary function is affected by HIV infection which most likely results from co-infection with TB or other pneumonia. Further research should focus on the influence of a pulmonary infection, most notably TB, on pulmonary function, especially as the incidence of TB is high in HIV infection.
Defective proviruses significantly impact viral transcription and immune activation in men and women with HIV-1 subtype C in rural South Africa
The main obstacle to achieving an HIV-1 cure is the proviral reservoir. To promote equity in HIV cure strategies, it is crucial to study the viral reservoir of the predominant HIV-1 subtype C in both women and men. Therefore, we investigated the dynamics of the (intact) viral reservoir in relation to plasma viral load (VL), CD4 T cell count, and immune activation before and during 96 weeks of successful antiretroviral therapy (ART). Eighty-two participants (62% female) newly initiating ART in a rural clinic in South Africa were included in the study. Blood samples were collected at baseline, week 48, and week 96, and CD4 count was determined. Plasma was used for VL and immune marker analyses, while isolated peripheral blood mononuclear cells (PBMCs) were used for the quantification of cellular multiple spliced HIV-1 RNA (msRNA) and the intact proviral DNA assay. For the longitudinal analyses on ART, we selected only those participants who durably suppressed their VL to <200 copies/mL during 48 (n=65) and/or 96 (n=60) weeks of treatment. At ART initiation, the median CD4 count was 234 cells/mm3 and VL was 68,897 copies/mL. Interestingly, at baseline the number of defective proviruses was significantly correlated with VL (p<0.0001), msRNA (p<0.0001), CD4 count (p=0.0008), CXCL10 (p=0.0003) and TNF-α (p=0.0394). During successful ART, a significant decrease of both the intact and defective proviral reservoir was observed (p<0.0001). The decrease of the intact proviral reservoir was more profound compared to the defective fraction after 96 weeks of therapy. In addition, a significant decrease in cellular msRNA and IL-6, IL-7, TNF-α, sCD14, sCD163, CCL2, CXCL10, and CRP was detected. This study underscores the significant relationship observed prior to therapy initiation between the number of defective proviruses, viral transcription/production and their association with immune response indicators such as CD4 count, CXCL10, and TNF-α. Furthermore, the observation of a less pronounced decrease of the defective proviral DNA highlights the importance of addressing both intact and defective proviruses in therapeutic strategies to enhance clinical outcomes for people with HIV-1. Together, these findings suggest a significant role of the defective proviruses in HIV-related disease progression.
Albuminuria Is Associated with Traditional Cardiovascular Risk Factors and Viral Load in HIV-Infected Patients in Rural South Africa
As life expectancy improves among Human Immunodeficiency Virus (HIV) patients, renal and cardiovascular diseases are increasingly prevalent in this population. Renal and cardiovascular disease are mutual risk factors and are characterized by albuminuria. Understanding the interactions between HIV, cardiovascular risk factors and renal disease is the first step in tackling this new therapeutic frontier in HIV. In a rural primary health care centre, 903 HIV-infected adult patients were randomly selected and data on HIV-infection and cardiovascular risk factors were collected. Glomerular filtration rate (eGFR) was estimated. Albuminuria was defined as an Albumin-Creatinine-Ratio above 30 mg/g. Multivariate logistic regression analysis was used to analyse albuminuria and demographic, clinical and HIV-associated variables. The study population consisted of 903 HIV-infected patients, with a median age of 40 years (Inter-Quartile Range (IQR) 34-48 years), and included 625 (69%) women. The median duration since HIV diagnosis was 26 months (IQR 12-58 months) and 787 (87%) received antiretroviral therapy. Thirty-six (4%) of the subjects were shown to have diabetes and 205 (23%) hypertension. In the cohort, 21% had albuminuria and 2% an eGFR <60 mL/min/1.73m2. Albuminuria was associated with hypertension (adjusted odds ratio (aOR) 1.59; 95% confidence interval (CI) 1.05-2.41; p<0.05), total cholesterol (aOR 1.31; 95% CI 1.11-1.54; p<0.05), eGFR (aOR 0.98; 95% CI 0.97-0.99; p<0.001) and detectable viral load (aOR 2.74; 95% CI 1.56-4.79; p<0.001). Hypertension was undertreated: 78% were not receiving treatment, while another 11% were inadequately treated. No patients were receiving lipid-lowering medication. Glomerular filtration rate was well conserved, while albuminuria was common amongst HIV-infected patients in rural South Africa. Both cardiovascular and HIV-specific variables were associated with albuminuria. Improved cardiovascular risk prevention as well as adequate virus suppression might be the key to escape the vicious circle of renal failure and cardiovascular disease and improve the long-term prognosis of HIV-infected patients.
Sustained Virological Response on Second-Line Antiretroviral Therapy following Virological Failure in HIV-Infected Patients in Rural South Africa
This study aims to describe the virological, immunological and clinical efficacy of protease inhibitor (PI)-based second-line antiretroviral therapy (ART) in rural South Africa. An observational cohort study was performed on 210 patients (including 39 children) who initiated PI-based second-line therapy at least 12 months prior to data collection. Biannual clinical, immunological and virological monitoring was performed. Primary endpoints were adequate virological response (plasma HIV-1 RNA<400 copies/ml), full virological suppression (plasma HIV-1 RNA<50 copies/ml) and treatment failure (virological failure (plasma HIV-1 RNA>1000 after initial virological response) or on-going viremia (plasma HIV-1 RNA never<400 copies/ml for more than six months)). Data were analyzed by an on-treatment (OT) and intention-to-treat (ITT) approach. Analyses were primarily performed on the group of patients who switched following first-line virological failure. Median duration of follow-up after switch to second-line treatment was 20 months [IQR 11-35]. 191 patients had switched to second-line ART due to first-line virological failure. 139/191 of them (72.8%, ITT) were in care and on treatment at the end of follow-up and 11/191 (5.8%, ITT) had died. After twelve months, an adequate virological response was seen in 92/128 patients (71.9%, OT), of which 78/128 (60.9%, OT) experienced full virological suppression. Virological response remained stable after 24 months. Virological efficacy was similar amongst adult and pediatric patients. As in first-line ART, we observed a lack of correlation between virological failure and WHO-defined immunological failure. Good virological outcomes following first-line failure can be achieved with PI-based, second-line antiretroviral therapy in both adult and pediatric patients in rural South Africa. Retention rates were high and virological outcomes were sustainable during the two-year follow-up period, although persisting low-level viremia occurred in a subset of patients. The observed viro-immunological dissociation emphasizes the need for virological monitoring.
Effect of HIV-1 low-level viraemia during antiretroviral therapy on treatment outcomes in WHO-guided South African treatment programmes: a multicentre cohort study
Antiretroviral therapy (ART) that enables suppression of HIV replication has been successfully rolled out at large scale to HIV-positive patients in low-income and middle-income countries. WHO guidelines for these regions define failure of ART with a lenient threshold of viraemia (HIV RNA viral load ≥1000 copies per mL). We investigated the occurrence of detectable viraemia during ART below this threshold and its effect on treatment outcomes in a large South African cohort. In this observational cohort study, we included HIV-positive adults registered between Jan 1, 2007, and May 1, 2016, at 57 clinical sites in South Africa, who were receiving WHO-recommended ART regimens and viral load monitoring. Low-level viraemia was defined as the occurrence of at least one viral load measurement of 51–999 copies per mL during ART. Outcomes were WHO-defined virological failure (one or more viral load measurement of ≥1000 copies per mL) and switch to second-line ART. Risks were estimated with Cox proportional hazard models. 70 930 patients were included in the analysis, of whom 67 644 received first-line ART, 1476 received second-line ART, and 1810 received both. Median duration of follow-up was 124 weeks (IQR 56–221) for patients on first-line ART and 101 weeks (IQR 51–178) for patients on second-line ART. Low-level viraemia occurred in 16 013 (23%) of 69 454 patients, with an incidence of 11·5 per 100 person-years of follow-up (95% CI 11·4–11·7), during first-line ART. Virological failure during follow-up occurred in 14 380 (22%) of 69 454 patients on first-line ART. Low-level viraemia was associated with increased hazards of virological failure (hazard ratio [HR] 2·6, 95% CI 2·5–2·8; p<0·0001) and switch to second-line ART (HR 5·2, 4·4–6·1; p<0·0001]) compared with virological suppression of less than 50 copies per mL. Risk of virological failure increased further with higher ranges and persistence of low-level viraemia. In this large cohort, low-level viraemia occurred frequently and increased the risk of virological failure and switch to second-line ART. Strategies for management of low-level viraemia need to be incorporated into WHO guidelines to meet UNAIDS-defined targets aimed at halting the global HIV epidemic. None.
Comparative performance of cardiovascular risk prediction models in people living with HIV
BackgroundCurrent cardiovascular risk assessment in people living with HIV is based on general risk assessment tools; however, whether these tools can be applied in sub-Saharan African populations has been questioned.ObjectivesThe study aimed to assess cardiovascular risk classification of common cardiovascular disease (CVD) risk prediction models compared to the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) 2010 and 2016 models in people living with HIV.MethodCardiovascular disease risk was estimated by Framingham Cardiovascular and Heart Disease (FHS-CVD, FHS-CHD), Atherosclerotic Cardiovascular Disease (ASCVD) and D:A:D 2010 and 2016 risk prediction models for HIV-infected participants of the Ndlovu Cohort Study, Limpopo, rural South Africa. Participants were classified to be at low ( 20%) of CVD within 10 years for general CVD and five years for D:A:D models. Kappa statistics were used to determine agreement between CVD risk prediction models. Subgroup analysis was performed according to age.ResultsThe analysis comprised 735 HIV-infected individuals, predominantly women (56.7%), average age 43.9 (8.8) years. The median predicted CVD risk for D:A:D 2010 and FHS-CVD was 4% and for ASCVD and FHS-CHD models, 3%. For the D:A:D 2016 risk prediction model, the figure was 5%. High 10-year CVD risk was predicted for 2.9%, 0.5%, 0.7%, 3.1% and 6.6% of the study participants by FHS-CVD, FHS-CHD, ASCVD, and D:A:D 2010 and 2016. Kappa statistics ranged from 0.34 for ASCVD to 0.60 for FHS-CVD as compared to the D:A:D 2010 risk prediction model.ConclusionOverall, predicted CVD risk is low in this population. Compared to D:A:D 2010, CVD risk estimated by the FHS-CVD model showed similar overall results for risk classification. With the exception of the D:A:D model, all other risk prediction models classified fewer people to be at high estimated CVD risk. Prospective studies are needed to develop and validate CVD risk algorithms in people living with HIV in sub-Saharan Africa.