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1.
Antimicrob Agents Chemother ; 68(5): e0158323, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38597667

RESUMO

Clofazimine is included in drug regimens to treat rifampicin/drug-resistant tuberculosis (DR-TB), but there is little information about its interaction with other drugs in DR-TB regimens. We evaluated the pharmacokinetic interaction between clofazimine and isoniazid, linezolid, levofloxacin, and cycloserine, dosed as terizidone. Newly diagnosed adults with DR-TB at Klerksdorp/Tshepong Hospital, South Africa, were started on the then-standard treatment with clofazimine temporarily excluded for the initial 2 weeks. Pharmacokinetic sampling was done immediately before and 3 weeks after starting clofazimine, and drug concentrations were determined using validated liquid chromatography-tandem mass spectrometry assays. The data were interpreted with population pharmacokinetics in NONMEM v7.5.1 to explore the impact of clofazimine co-administration and other relevant covariates on the pharmacokinetics of isoniazid, linezolid, levofloxacin, and cycloserine. Clofazimine, isoniazid, linezolid, levofloxacin, and cycloserine data were available for 16, 27, 21, 21, and 6 participants, respectively. The median age and weight for the full cohort were 39 years and 52 kg, respectively. Clofazimine exposures were in the expected range, and its addition to the regimen did not significantly affect the pharmacokinetics of the other drugs except levofloxacin, for which it caused a 15% reduction in clearance. A posteriori power size calculations predicted that our sample sizes had 97%, 90%, and 87% power at P < 0.05 to detect a 30% change in clearance of isoniazid, linezolid, and cycloserine, respectively. Although clofazimine increased the area under the curve of levofloxacin by 19%, this is unlikely to be of great clinical significance, and the lack of interaction with other drugs tested is reassuring.


Assuntos
Antituberculosos , Clofazimina , Ciclosserina , Interações Medicamentosas , Isoniazida , Levofloxacino , Linezolida , Tuberculose Resistente a Múltiplos Medicamentos , Clofazimina/farmacocinética , Clofazimina/uso terapêutico , Humanos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Adulto , Antituberculosos/farmacocinética , Antituberculosos/uso terapêutico , Masculino , Feminino , Linezolida/farmacocinética , Linezolida/uso terapêutico , Isoniazida/farmacocinética , Isoniazida/uso terapêutico , Levofloxacino/farmacocinética , Levofloxacino/uso terapêutico , Ciclosserina/farmacocinética , Ciclosserina/uso terapêutico , Pessoa de Meia-Idade , África do Sul , Adulto Jovem , Quimioterapia Combinada
2.
N Engl J Med ; 384(18): 1705-1718, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33951360

RESUMO

BACKGROUND: Rifapentine-based regimens have potent antimycobacterial activity that may allow for a shorter course in patients with drug-susceptible pulmonary tuberculosis. METHODS: In an open-label, phase 3, randomized, controlled trial involving persons with newly diagnosed pulmonary tuberculosis from 13 countries, we compared two 4-month rifapentine-based regimens with a standard 6-month regimen consisting of rifampin, isoniazid, pyrazinamide, and ethambutol (control) using a noninferiority margin of 6.6 percentage points. In one 4-month regimen, rifampin was replaced with rifapentine; in the other, rifampin was replaced with rifapentine and ethambutol with moxifloxacin. The primary efficacy outcome was survival free of tuberculosis at 12 months. RESULTS: Among 2516 participants who had undergone randomization, 2343 had a culture positive for Mycobacterium tuberculosis that was not resistant to isoniazid, rifampin, or fluoroquinolones (microbiologically eligible population; 768 in the control group, 791 in the rifapentine-moxifloxacin group, and 784 in the rifapentine group), of whom 194 were coinfected with human immunodeficiency virus and 1703 had cavitation on chest radiography. A total of 2234 participants could be assessed for the primary outcome (assessable population; 726 in the control group, 756 in the rifapentine-moxifloxacin group, and 752 in the rifapentine group). Rifapentine with moxifloxacin was noninferior to the control in the microbiologically eligible population (15.5% vs. 14.6% had an unfavorable outcome; difference, 1.0 percentage point; 95% confidence interval [CI], -2.6 to 4.5) and in the assessable population (11.6% vs. 9.6%; difference, 2.0 percentage points; 95% CI, -1.1 to 5.1). Noninferiority was shown in the secondary and sensitivity analyses. Rifapentine without moxifloxacin was not shown to be noninferior to the control in either population (17.7% vs. 14.6% with an unfavorable outcome in the microbiologically eligible population; difference, 3.0 percentage points [95% CI, -0.6 to 6.6]; and 14.2% vs. 9.6% in the assessable population; difference, 4.4 percentage points [95% CI, 1.2 to 7.7]). Adverse events of grade 3 or higher occurred during the on-treatment period in 19.3% of participants in the control group, 18.8% in the rifapentine-moxifloxacin group, and 14.3% in the rifapentine group. CONCLUSIONS: The efficacy of a 4-month rifapentine-based regimen containing moxifloxacin was noninferior to the standard 6-month regimen in the treatment of tuberculosis. (Funded by the Centers for Disease Control and Prevention and others; Study 31/A5349 ClinicalTrials.gov number, NCT02410772.).


Assuntos
Antibióticos Antituberculose/administração & dosagem , Antituberculosos/uso terapêutico , Moxifloxacina/administração & dosagem , Mycobacterium tuberculosis/isolamento & purificação , Rifampina/administração & dosagem , Tuberculose Pulmonar/tratamento farmacológico , Adolescente , Adulto , Antibióticos Antituberculose/efeitos adversos , Antituberculosos/efeitos adversos , Criança , Intervalos de Confiança , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Masculino , Moxifloxacina/efeitos adversos , Rifampina/efeitos adversos , Adulto Jovem
3.
BMC Infect Dis ; 24(1): 336, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515050

RESUMO

BACKGROUND: Data on the characteristics of individuals with mild and asymptomatic infections with different SARS-CoV-2 variants are limited. We therefore compared the characteristics of individuals infected with ancestral, Beta and Delta SARS-CoV-2 variants in South Africa. METHODS: We conducted a prospective cohort study in a rural and an urban site during July 2020-August 2021. Mid-turbinate nasal swabs were collected twice-weekly from household members irrespective of symptoms and tested for SARS-CoV-2 using real-time reverse transcription polymerase chain reaction (rRT-PCR). Differences in demographic and clinical characteristics, shedding and cycle threshold (Ct) value of infection episodes by variant were evaluated using multinomial regression. Overall and age-specific incidence rates of infection were compared by variant. RESULTS: We included 1200 individuals from 222 households and 648 rRT-PCR-confirmed infection episodes (66, 10% ancestral, 260, 40% Beta, 322, 50% Delta). Symptomatic proportion was similar for ancestral (7, 11%), Beta (44, 17%), and Delta (46, 14%) infections (p=0.4). After accounting for previous infection, peak incidence shifted to younger age groups in successive waves (40-59 years ancestral, 19-39 years Beta, 13-18 years Delta). On multivariable analysis, compared to ancestral, Beta infection was more common in individuals aged 5-12 years (vs 19-39)(adjusted odds ratio (aOR) 2.6, 95% confidence interval (CI)1.1-6.6) and PCR cycle threshold (Ct) value <30 (vs >35)(aOR 3.2, 95%CI 1.3-7.9), while Delta was more common in individuals aged <5 (aOR 6.7, 95%CI1.4-31.2) and 5-12 years (aOR 6.6 95%CI2.6-16.7)(vs 19-39) and Ct value <30 (aOR 4.5, 95%CI 1.3-15.5) and 30-35 (aOR 6.0, 95%CI 2.3-15.7)(vs >35). CONCLUSIONS: Consecutive SARS-CoV-2 waves with Beta and Delta variants were associated with a shift to younger individuals. Beta and Delta infections were associated with higher peak viral loads, potentially increasing infectiousness.


Assuntos
COVID-19 , Humanos , África do Sul/epidemiologia , COVID-19/epidemiologia , Estudos de Coortes , Estudos Prospectivos , SARS-CoV-2/genética
4.
Clin Infect Dis ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38051643

RESUMO

BACKGROUND: Twenty-three percent of people with HIV (PWH) die within 6-months of hospital discharge. We tested the hypothesis whether a series of structured home visits could reduce mortality. METHODS: We designed a disease neutral home visit package with up to 6 home visits starting 1-week post-hospitalization and every 2 weeks thereafter. The home visit team used a structured assessment algorithm to evaluate and triage social and medical needs of the participant and provide nutritional support. We compared all-cause mortality 6-months following discharge for the intervention compared to usual care in a pilot randomized trial conducted in South Africa. To inform potential scale-up we also included and separately analyzed a group of people without HIV (PWOH). RESULTS: We enrolled 125 people with HIV and randomized them 1:1 to the home visit intervention or usual care. Fourteen were late exclusions because of death prior to discharge or delayed discharge leaving 111 for analysis. The median age was 39 years, 31% were men; and 70% had advanced HIV disease. At six months among PWH 4 (7.3%) in the home visit arm and 10 (17.9%) in the usual care arm (p = 0.09) had died. Among the 70 PWOH enrolled overall 6-month mortality was 10.1%. Of those in the home visit arm, 91% received at least one home visit. CONCLUSIONS: We demonstrated feasibility of delivering post-hospital home visits and demonstrated preliminary efficacy among PWH with a substantial, but not statistically significant, effect size (59% reduction in mortality). COVID-19 related challenges resulted in under-enrollment.

5.
Clin Infect Dis ; 76(9): 1594-1603, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-36610730

RESUMO

BACKGROUND: We report the yield of targeted universal tuberculosis (TB) testing of clinic attendees in high-risk groups. METHODS: Clinic attendees in primary healthcare facilities in South Africa with one of the following risk factors underwent sputum testing for TB: human immunodeficiency virus (HIV), contact with a TB patient in the past year, and having had TB in the past 2 years. A single sample was collected for Xpert-Ultra (Xpert) and culture. We report the proportion positive for Mycobacterium tuberculosis. Data were analyzed descriptively. The unadjusted clinical and demographic factors' relative risk of TB detected by culture or Xpert were calculated and concordance between Xpert and culture is described. RESULTS: A total of 30 513 participants had a TB test result. Median age was 39 years, and 11 553 (38%) were men. The majority (n = 21734, 71%) had HIV, 12 492 (41%) reported close contact with a TB patient, and 1573 (5%) reported prior TB. Overall, 8.3% were positive for M. tuberculosis by culture and/or Xpert compared with 6.0% with trace-positive results excluded. In asymptomatic participants, the yield was 6.7% and 10.1% in symptomatic participants (with trace-positives excluded). Only 10% of trace-positive results were culture-positive. We found that 55% of clinic attendees with a sputum result positive for M. tuberculosis did not have a positive TB symptom screen. CONCLUSIONS: A high proportion of clinic attendees with specific risk factors (HIV, close TB contact, history of TB) test positive for M. tuberculosis when universal testing is implemented.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Tuberculose , Masculino , Humanos , Adulto , Feminino , África do Sul/epidemiologia , Sensibilidade e Especificidade , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Mycobacterium tuberculosis/genética , HIV , Atenção Primária à Saúde , Escarro/microbiologia
6.
Clin Infect Dis ; 76(3): e710-e717, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35717655

RESUMO

BACKGROUND: Longitudinal pneumococcus colonization data in high human immunodeficiency virus (HIV) prevalence settings following pneumococcal conjugate vaccine introduction are limited. METHODS: In 327 randomly selected households, 1684 individuals were enrolled and followed-up for 6 to 10 months during 2016 through 2018 from 2 communities. Nasopharyngeal swabs were collected twice weekly and tested for pneumococcus using quantitative lytA real-time polymerase chain reaction. A Markov model was fitted to the data to define the start and end of an episode of colonization. We assessed factors associated with colonization using logistic regression. RESULTS: During the study period, 98% (1655/1684) of participants were colonized with pneumococcus at least once. Younger age (<5 years: adjusted odds ratio [aOR], 14.1; 95% confidence [CI], 1.8-111.3, and 5-24 years: aOR, 4.8, 95% CI, 1.9-11.9, compared with 25-44 years) and HIV infection (aOR, 10.1; 95% CI, 1.3-77.1) were associated with increased odds of colonization. Children aged <5 years had fewer colonization episodes (median, 9) than individuals ≥5 years (median, 18; P < .001) but had a longer episode duration (<5 years: 35.5 days; interquartile range, 17-88) vs. ≥5 years: 5.5 days (4-12). High pneumococcal loads were associated with age (<1 year: aOR 25.4; 95% CI, 7.4-87.6; 1-4 years: aOR 13.5, 95% CI 8.3-22.9; 5-14 years: aOR 3.1, 95% CI, 2.1-4.4 vs. 45-65 year old patients) and HIV infection (aOR 1.7; 95% CI 1.2-2.4). CONCLUSIONS: We observed high levels of pneumococcus colonization across all age groups. Children and people with HIV were more likely to be colonized and had higher pneumococcal loads. Carriage duration decreased with age highlighting that children remain important in pneumococcal transmission.


Assuntos
Infecções por HIV , Infecções Pneumocócicas , Criança , Humanos , Lactente , Pessoa de Meia-Idade , Idoso , Streptococcus pneumoniae , Infecções Pneumocócicas/prevenção & controle , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , HIV , África do Sul/epidemiologia , Prevalência , Nasofaringe , Vacinas Pneumocócicas , Portador Sadio/epidemiologia , Portador Sadio/prevenção & controle
7.
Clin Infect Dis ; 76(3): e71-e81, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35925613

RESUMO

BACKGROUND: In South Africa, 19% of adults are living with human immunodeficiency virus (HIV; LWH). Few data on the influence of HIV on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) household transmission are available. METHODS: We performed a case-ascertained, prospective household transmission study of symptomatic adult index SARS-CoV-2 cases LWH and not living with HIV (NLWH) and their contacts from October 2020 to September 2021. Households were followed up 3 times a week for 6 weeks to collect nasal swabs for SARS-CoV-2 testing. We estimated household cumulative infection risk (HCIR) and duration of SARS-CoV-2 positivity (at a cycle threshold value <30 as proxy for high viral load). RESULTS: HCIR was 59% (220 of 373), not differing by index HIV status (60% LWH vs 58% NLWH). HCIR increased with index case age (35-59 years: adjusted OR [aOR], 3.4; 95% CI, 1.5-7.8 and ≥60 years: aOR, 3.1; 95% CI, 1.0-10.1) compared with 18-34 years and with contacts' age, 13-17 years (aOR, 7.1; 95% CI, 1.5-33.9) and 18-34 years (aOR, 4.4; 95% CI, 1.0-18.4) compared with <5 years. Mean positivity was longer in cases LWH (adjusted hazard ratio, 0.4; 95% CI, .1-.9). CONCLUSIONS: Index HIV status was not associated with higher HCIR, but cases LWH had longer positivity duration. Adults aged >35 years were more likely to transmit and individuals aged 13-34 to be infected SARS-CoV-2 in the household. As HIV infection may increase transmission, health services must maintain HIV testing and antiretroviral therapy initiation.


Assuntos
COVID-19 , Infecções por HIV , Adulto , Humanos , Adolescente , SARS-CoV-2 , COVID-19/epidemiologia , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , HIV , Teste para COVID-19 , África do Sul/epidemiologia , Estudos Prospectivos
8.
Emerg Infect Dis ; 29(2): 294-303, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36692337

RESUMO

We conducted 3 prospective cohort studies (2016-2018), enrolling persons from 2 communities in South Africa. Nasopharyngeal swab specimens were collected twice a week from participants. Factors associated with Bordetella pertussis incidence, episode duration, and household transmission were determined by using Poisson regression, Weibull accelerated time-failure, and logistic regression hierarchical models, respectively. Among 1,684 participants, 118 episodes of infection were detected in 107 participants (incidence 0.21, 95% CI 0.17-0.25 infections/100 person-weeks). Children <5 years of age who had incomplete vaccination were more likely to have pertussis infection. Episode duration was longer for participants who had higher bacterial loads. Transmission was more likely to occur from male index case-patients and persons who had >7 days infection duration. In both communities, there was high incidence of B. pertussis infection and most cases were colonized.


Assuntos
Coqueluche , Criança , Humanos , Masculino , Coqueluche/epidemiologia , Bordetella pertussis , África do Sul/epidemiologia , Estudos Prospectivos , Incidência
9.
PLoS Med ; 20(5): e1004237, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37216385

RESUMO

BACKGROUND: The World Health Organization (WHO) recommends systematic symptom screening for tuberculosis (TB). However, TB prevalence surveys suggest that this strategy does not identify millions of TB patients, globally. Undiagnosed or delayed diagnosis of TB contribute to TB transmission and exacerbate morbidity and mortality. We conducted a cluster-randomized trial of large urban and rural primary healthcare clinics in 3 provinces of South Africa to evaluate whether a novel intervention of targeted universal testing for TB (TUTT) in high-risk groups diagnosed more patients with TB per month compared to current standard of care (SoC) symptom-directed TB testing. METHODS AND FINDINGS: Sixty-two clinics were randomized; with initiation of the intervention clinics over 6 months from March 2019. The study was prematurely stopped in March 2020 due to clinics restricting access to patients, and then a week later due to the Coronavirus Disease 2019 (COVID-19) national lockdown; by then, we had accrued a similar number of TB diagnoses to that of the power estimates and permanently stopped the trial. In intervention clinics, attendees living with HIV, those self-reporting a recent close contact with TB, or a prior episode of TB were all offered a sputum test for TB, irrespective of whether they reported symptoms of TB. We analyzed data abstracted from the national public sector laboratory database using Poisson regression models and compared the mean number of TB patients diagnosed per clinic per month between the study arms. Intervention clinics diagnosed 6,777 patients with TB, 20.7 patients with TB per clinic month (95% CI 16.7, 24.8) versus 6,750, 18.8 patients with TB per clinic month (95% CI 15.3, 22.2) in control clinics during study months. A direct comparison, adjusting for province and clinic TB case volume strata, did not show a significant difference in the number of TB cases between the 2 arms, incidence rate ratio (IRR) 1.14 (95% CI 0.94, 1.38, p = 0.46). However, prespecified difference-in-differences analyses showed that while the rate of TB diagnoses in control clinics decreased over time, intervention clinics had a 17% relative increase in TB patients diagnosed per month compared to the prior year, interaction IRR 1.17 (95% CI 1.14, 1.19, p < 0.001). Trial limitations were the premature stop due to COVID-19 lockdowns and the absence of between-arm comparisons of initiation and outcomes of TB treatment in those diagnosed with TB. CONCLUSIONS: Our trial suggests that the implementation of TUTT in these 3 groups at extreme risk of TB identified more TB patients than SoC and could assist in reducing undiagnosed TB patients in settings of high TB prevalence. TRIAL REGISTRATION: South African National Clinical Trials Registry DOH-27-092021-4901.


Assuntos
COVID-19 , Infecções por HIV , Tuberculose , Humanos , África do Sul/epidemiologia , COVID-19/diagnóstico , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Tuberculose/tratamento farmacológico , Atenção Primária à Saúde , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/tratamento farmacológico
10.
Clin Infect Dis ; 75(5): 849-856, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34950944

RESUMO

BACKGROUND: Household contact tracing for tuberculosis (TB) may facilitate diagnosis and access to TB preventive treatment (TPT). We investigated whether household contact tracing and intensive TB/human immunodeficiency virus (HIV) screening would improve TB-free survival. METHODS: Household contacts of index TB patients in 2 South African provinces were randomized to home tracing and intensive HIV/TB screening or standard of care (SOC; clinic referral letters). The primary outcome was incident TB or death at 15 months. Secondary outcomes included tuberculin skin test (TST) positivity in children ≤14 years and undiagnosed HIV. RESULTS: From December 2016 through March 2019, 1032 index patients (4459 contacts) and 1030 (4129 contacts) were randomized to the intervention and SOC arms. Of intervention arm contacts, 3.2% (69 of 2166) had prevalent microbiologically confirmed TB. At 15 months, the cumulative incidence of TB or death did not differ between the intensive screening (93 of 3230, 2.9%) and SOC (80 of 2600, 3.1%) arms (hazard ratio, 0.90; 95% confidence interval [CI], .66-1.24). TST positivity was higher in the intensive screening arm (38 of 845, 4.5%) compared with the SOC arm (15 of 800, 1.9%; odds ratio, 2.25; 95% CI, 1.07-4.72). Undiagnosed HIV was similar between arms (41 of 3185, 1.3% vs 32 of 2543, 1.3%; odds ratio, 1.02; 95% CI, .64-1.64). CONCLUSIONS: Household contact tracing with intensive screening and referral did not reduce incident TB or death. Providing referral letters to household contacts of index patients is an alternative strategy to home visits. CLINICAL TRIALS REGISTRATION: ISRCTN16006202.


Assuntos
Infecções por HIV , Tuberculose , Criança , Busca de Comunicante , HIV , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , África do Sul/epidemiologia , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Tuberculose/prevenção & controle
11.
Emerg Infect Dis ; 28(5): 1055-1058, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35320701

RESUMO

By November 2021, after the third wave of severe acute respiratory syndrome coronavirus 2 infections in South Africa, seroprevalence was 60% in a rural community and 70% in an urban community. High seroprevalence before the Omicron variant emerged may have contributed to reduced illness severity observed in the fourth wave.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Humanos , Estudos Soroepidemiológicos , África do Sul/epidemiologia
12.
Emerg Infect Dis ; 27(12): 3020-3029, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34477548

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections may be underestimated because of limited access to testing. We measured SARS-CoV-2 seroprevalence in South Africa every 2 months during July 2020-March 2021 in randomly selected household cohorts in 2 communities. We compared seroprevalence to reported laboratory-confirmed infections, hospitalizations, and deaths to calculate infection-case, infection-hospitalization, and infection-fatality ratios in 2 waves of infection. Post-second wave seroprevalence ranged from 18% in the rural community children <5 years of age, to 59% in urban community adults 35-59 years of age. The second wave saw a shift in age distribution of case-patients in the urban community (from persons 35-59 years of age to persons at the extremes of age), higher attack rates in the rural community, and a higher infection-fatality ratio in the urban community. Approximately 95% of SARS-CoV-2 infections were not reported to national surveillance.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Criança , Humanos , Pessoa de Meia-Idade , População Rural , Estudos Soroepidemiológicos , África do Sul/epidemiologia
13.
Clin Chem ; 67(11): 1524-1533, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34491318

RESUMO

BACKGROUND: Clonal immunoglobulin and T-cell receptor rearrangements serve as tumor-specific markers that have become mainstays of the diagnosis and monitoring of lymphoid malignancy. Next-generation sequencing (NGS) techniques targeting these loci have been successfully applied to lymphoblastic leukemia and multiple myeloma for minimal residual disease detection. However, adoption of NGS for primary diagnosis remains limited. METHODS: We addressed the bioinformatics challenges associated with immune cell sequencing and clone detection by designing a novel web tool, CloneRetriever (CR), which uses machine-learning principles to generate clone classification schemes that are customizable, and can be applied to large datasets. CR has 2 applications-a "validation" mode to derive a clonality classifier, and a "live" mode to screen for clones by applying a validated and/or customized classifier. In this study, CR-generated multiple classifiers using 2 datasets comprising 106 annotated patient samples. A custom classifier was then applied to 36 unannotated samples. RESULTS: The optimal classifier for clonality required clonal dominance ≥4.5× above background, read representation ≥8% of all reads, and technical replicate agreement. Depending on the dataset and analysis step, the optimal algorithm yielded sensitivities of 81%-90%, specificities of 97%-100%, areas under the curve of 91%-94%, positive predictive values of 92-100%, and negative predictive values of 88%-98%. Customization of the algorithms yielded 95%-100% concordance with gold-standard clonality determination, including rescue of indeterminate samples. Application to a set of unknowns showed concordance rates of 83%-96%. CONCLUSIONS: CR is an out-of-the-box ready and user-friendly software designed to identify clonal rearrangements in large NGS datasets for the diagnosis of lymphoid malignancies.


Assuntos
Rearranjo Gênico do Linfócito T , Sequenciamento de Nucleotídeos em Larga Escala , Algoritmos , Rearranjo Gênico , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Neoplasia Residual/diagnóstico
14.
BMC Public Health ; 21(1): 1055, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34078327

RESUMO

BACKGROUND: Describing contact patterns is crucial to understanding infectious disease transmission dynamics and guiding targeted transmission mitigation interventions. Data on contact patterns in Africa, especially South Africa, are limited. We measured and compared contact patterns in a rural and urban community, South Africa. We assessed participant and contact characteristics associated with differences in contact rates. METHODS: We conducted a cross-sectional study nested in a prospective household cohort study. We interviewed participants to collect information on persons in contact with for one day. We described self-reported contact rates as median number people contacted per day, assessed differences in contact rates based on participant characteristics using quantile regression, and used a Poisson model to assess differences in contact rates based on contact characteristics within age groups. We also calculated cumulative person hours in contact within age groups at different locations. RESULTS: We conducted 535 interviews (269 rural, 266 urban), with 17,252 contacts reported. The overall contact rate was 14 (interquartile range (IQR) 9-33) contacts per day. Those ≤18 years had higher contact rates at the rural site (coefficient 17, 95% confidence interval (95%CI) 10-23) compared to the urban site, for those aged 14-18 years (13, 95%CI 3-23) compared to < 7 years. No differences were observed for adults. There was a strong age-based mixing, with age groups interacting more with similar age groups, but also interaction of participants of all ages with adults. Children aged 14-18 years had the highest cumulative person hours in contact (116.3 rural and 76.4 urban). CONCLUSIONS: Age played an important role in the number and duration of contact events, with children at the rural site having almost double the contact rate compared to the urban site. These contact rates can be utilized in mathematical models to assess transmission dynamics of infectious diseases in similar communities.


Assuntos
População Rural , Adulto , Criança , Estudos de Coortes , Estudos Transversais , Humanos , Estudos Prospectivos , África do Sul/epidemiologia , População Urbana
15.
BMC Health Serv Res ; 21(1): 17, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407395

RESUMO

BACKGROUND: The uptake and adherence of daily oral PrEP has been poor in high-risk populations in South Africa including young people. We used qualitative research methods to explore user preferences for daily and on-demand oral PrEP use among young South Africans, and to inform the identification of critical attributes and attribute-levels for quantitative analysis of user preferences, i.e. a discrete choice experiment (DCE). METHODS: Data were collected between September and November 2018 from eight group discussions and 20 in-depth interviews with young people 13 to 24 years in Cape Town and Johannesburg. Using a convenience sampling strategy, participants were stratified by sex and age. Interviewers used a semi-structured interview guide to discuss several attributes (dosing regimen, location, costs, side effects, and protection period) for PrEP access and use. Group discussions and in-depth interviews were audio-recorded, transcribed verbatim and translated to English. We used framework analysis to explore context-specific attributes and attribute-levels for delivering oral PrEP in South Africa. The adolescent community advisory board, expert and study team opinions were consulted for the final DCE attributes and levels. RESULTS: We enrolled 74 participants who were 51% (n = 38/74) male, had a median age of 18.5 [Interquartile range = 16-21.25] years, 91% (n = 67/74) identified as heterosexual and 49% (n = 36/74) had not completed 12th grade education. Using the qualitative data, we identified five candidate attributes including (1) dosing regimen, (2) location to get PrEP, (3) cost, (4) route of administration and (5) frequency. After discussions with experts and the study team, we revised the DCE to include the following five attributes and levels: dosing regime: daily, and on-demand PrEP; location: private pharmacy, public clinic, mobile clinic, ATM); cost: free-of-charge, R50 (~2GBP), R265 (~12GBP); side effects: nausea, headache, rash; and duration of protection: fulltime protection versus when PrEP is used). CONCLUSIONS: There is limited literature on qualitative research methods describing the step-by-step process of developing a DCE for PrEP in adolescents, especially in resource-constrained countries. We provide the process followed for the DCE technique to understand user preferences for daily and on-demand oral PrEP among young people in South Africa.


Assuntos
Infecções por HIV , Profilaxia Pré-Exposição , Adolescente , Infecções por HIV/prevenção & controle , Heterossexualidade , Humanos , Masculino , Pesquisa Qualitativa , África do Sul , Adulto Jovem
16.
AIDS Behav ; 24(4): 1106-1117, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31549265

RESUMO

Isoniazid preventive therapy (IPT) reduces the risk of active tuberculosis among people living with HIV, but implementation of IPT in South Africa and elsewhere remains slow. The objective of this study was to examine both nurse perceptions of clinical mentorship and patient perceptions of in-queue health education for promoting IPT uptake in Potchefstroom, South Africa. We measured adoption, fidelity, acceptability, and sustainability of the interventions using both quantitative and qualitative methods. Adoption, fidelity, and acceptability of the interventions were moderately high. However, nurses believed they could not sustain their increased prescriptions of IPT, and though many patients intended to ask nurses about IPT, few did. Most patients attributed their behavior to an imbalance of patient-provider power. National IPT guidelines should be unambiguous and easily implemented after minimal training on patient eligibility and appropriate medication durations, nurse-patient dynamics should empower the patient, and district-level support and monitoring should be implemented.


Assuntos
Infecções por HIV , Tuberculose , Antituberculosos/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Promoção da Saúde , Humanos , Isoniazida , Masculino , África do Sul/epidemiologia , Tuberculose/tratamento farmacológico , Tuberculose/prevenção & controle
17.
AIDS Behav ; 24(12): 3511-3521, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32415616

RESUMO

South Africa processes 5.1 million HIV CD4, viral load (VL), and tuberculosis (TB) tests annually. This pilot non-randomized trial in South Africa explored an intervention ("MatlaMobile") to deliver laboratory results via mobile phone. Adults completing CD4, VL, and/or TB laboratory tests were enrolled-either receiving results by returning to clinic (control, n = 174) or mobile phone (intervention, n = 226). Study staff instructed control participants to return within 6 days (standard-of-care). MatlaMobile instructed intervention participants with clinically actionable results requiring intervention or treatment change (i.e., < 200 CD4 cells per milliliter, ≥ 400 viral copies per milliliter, or TB positive) to return immediately. A greater proportion of intervention participants than controls saw their results within 7 days of enrollment (73% vs. 8.6%, p < 0.001). Among participants instructed to return, more intervention participants (20%, n = 14/70) returned than controls (8.6%, n = 15/174, p = 0.02). MatlaMobile demonstrated that patients can quickly receive and respond appropriately to digital delivery of health information.


Assuntos
Telefone Celular , Infecções por HIV , Tuberculose , Humanos , África do Sul , Carga Viral
18.
Genes Immun ; 20(8): 651-659, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30563969

RESUMO

In the HIV-1 Thai RV144 vaccine trial-the only trial to demonstrate any vaccine efficacy to date-a three-variant haplotype within the Fc gamma receptor 2C gene (FCGR2C) modified the risk of HIV-1 acquisition. A similar vaccine regimen is currently being evaluated in South Africa in the HVTN702 trial, where the predominant population is polymorphic for only a single variant in the haplotype, c.134-96C>T. To investigate the significance of c.134-96C>T in HIV-specific immunity in South Africans, this study assessed its role in HIV-1 disease progression. In a cohort of HIV-1-infected South African controllers (n = 71) and progressors (n = 73), the c.134-96C>T minor allele significantly associated with increased odds of HIV-1 disease progression (odds ratio 3.80, 95% confidence interval 1.90-7.62; P = 2.0 × 10-4, PBonf = 2.4 × 10-3). It is unlikely that the underlying mechanism involves wild-type FcγRIIc function, since only a single study participant was predicted to express wild-type FcγRIIc as determined by the FCGR2C c.798+1A>G splice-site variant. Conversely, in silico analysis revealed a potential role for c.134-96C> T in modulating mRNA transcription. In conclusion, these data provide additional evidence towards a role for FCGR2C c.134-96C>T in the context of HIV-1 and underscore the need to investigate its significance in the HVTN702 efficacy trial in South Africa.


Assuntos
Infecções por HIV/genética , Infecções por HIV/patologia , Receptores de IgG/genética , Vacinas contra a AIDS/imunologia , Adulto , Ensaios Clínicos Fase III como Assunto , Progressão da Doença , Feminino , Infecções por HIV/imunologia , Projeto Genoma Humano , Humanos , Masculino , África do Sul
19.
AIDS Behav ; 23(7): 1689-1697, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30415430

RESUMO

HIV-positive pregnant women who are initiated on lifelong antiretroviral therapy (ART) and isoniazid preventive therapy (IPT) have lower adherence rates after delivery. We quantified maternal motivation to take preventive therapy before and after delivery among pregnant women newly diagnosed with HIV. We enrolled pregnant women (≥ 18 years) with a recent HIV diagnosis (< 6 months) at 14 public primary health clinics in Matlosana, South Africa and followed them in the postpartum period. Participants received eight choice tasks comparing two mutually exclusive sub-sets of seven possible benefits related to preventive therapy identified through literature reviews and key informant interviews. Data was analyzed using conditional logit regression in the antepartum versus postpartum periods. Coefficients are reported with 95% confidence intervals (CI). Sixty-five women completed surveys both at enrollment and in the postpartum period. All women were already on ART, while 21 (32%) were receiving IPT at enrollment. The mean CD4 count was 436 (± 246) cells/mm3. In the antepartum period, preventing HIV transmission to partners was the most important benefit (coefficients (ß) = 0.87, 95% CI 0.64, 1.11), followed by keeping healthy for family (ß = 0.75, 95% CI 0.52, 0.97). Such prioritization significantly decreased in the postpartum period (p < 0.001). Compared to other motivators, keeping a high CD4 count was least prioritized in the antepartum period (ß = 0.19, 95% CI - 0.04, 0.43) but was most prioritized in the postpartum period (ß = 0.39, 95% CI 0.21, 0.57). These results highlight that messages on family might be particularly salient in the antepartum period, and keeping CD4 count high in the postpartum period. Understanding maternal motivation may help to design targeted health promotion messages to HIV-positive women around the time of delivery.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Período Periparto , Período Pós-Parto , Complicações Infecciosas na Gravidez/tratamento farmacológico , Gestantes/psicologia , Adulto , Feminino , Infecções por HIV/transmissão , Humanos , Recém-Nascido , Estudos Longitudinais , Adesão à Medicação/estatística & dados numéricos , Motivação , Gravidez , África do Sul
20.
BMC Infect Dis ; 19(1): 839, 2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31606032

RESUMO

BACKGROUND: Household contact tracing of index TB cases has been advocated as a key part of TB control for many years, but has not been widely implemented in many low-resource setting because of the current dearth of high quality evidence for effectiveness. Innovative strategies for earlier, more effective treatment are particularly important in contexts with hyper-endemic levels of HIV, where levels of TB infection remain extremely high. METHODS: We present the design of a household cluster-randomised controlled trial of interventions aimed at improving TB-free survival and reducing childhood prevalence of Mycobacterium tuberculosis infection among household contacts of index TB cases diagnosed in two provinces of South Africa. Households of index TB cases will be randomly allocated in a 1:1 ratio to receive either an intensified home screening and linkage for TB and HIV intervention, or enhanced standard of care. The primary outcome will compare between groups the TB-free survival of household contacts over 15 months. All participants, or their next-of-kin, will provide written informed consent to participate. DISCUSSION: Evidence from randomised trials is required to identify cost-effective approaches to TB case-finding that can be applied at scale in sub-Saharan Africa. TRIAL REGISTRATION: ISRCTN16006202 (01/02/2017: retrospectively registered) and NHREC4399 (11/04/2016: prospectively registered). Protocol version: 4.0 (date: 18th January 2018).


Assuntos
Busca de Comunicante/métodos , Tuberculose/prevenção & controle , Adulto , Criança , Análise Custo-Benefício , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Humanos , Estudos Retrospectivos , Risco , África do Sul/epidemiologia , Padrão de Cuidado , Resultado do Tratamento , Teste Tuberculínico , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Carga Viral
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