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1.
AIDS Patient Care STDS ; 36(4): 145-152, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35438521

RESUMO

We conducted a 24-month prospective follow-up study, at a primary health care clinic in Harare, Zimbabwe, to determine cumulative mother-to-child transmission of HIV-1 (MTCT) rate and the contributions of intrauterine (IU), intrapartum (IP), and postpartum (PP) to MTCT, as well as maternal and infant mortality rates in the era of Option B+ combination antiretroviral therapy (cART). Plasma for viral load (VL) quantitation was obtained from 475 mothers enrolled into the study. VL was quantified at enrolment and every 6 months thereafter up to 24 months using the Cepheid GeneXpert HIV-1 Quantitative test. Dried blood spots were collected from 453 infants at birth, 4-6 weeks, 3 months, and every 3 months thereafter up to 24 months. HIV-1 infant diagnosis was conducted using the Cepheid GeneXpert HIV-1 Qualitative test. Absolute, cumulative MTCT rates and mortality rate were calculated. Seven mothers (1.55%) transmitted HIV-1 infection to their infants by 24 months. Four infants (0.88%; 95% CI 0.26-2.33%), one infant (0.22%; 95% CI 0-1.4%), and two infants (0.44%; 95% CI 0.01-1.7%) were infected IU, IP, and PP, respectively. By 24 months, 88.94% of the mothers and 80% of the infants had undetectable VL. The maternal and infant mortality rates were 0.21% and 1.78%, respectively. In the first 24 months of life, IU transmission is the major route of MTCT. The cumulative MTCT rate of 1.55% and low maternal and infant mortality rates of 0.21% and 1.78%, respectively, contribute to growing evidence that Option B+ cART not only drastically reduces MTCT but also maternal and infant mortality.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Complicações Infecciosas na Gravidez , Terapia Antirretroviral de Alta Atividade , Feminino , Seguimentos , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Mães , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Atenção Primária à Saúde , Estudos Prospectivos , Zimbábue/epidemiologia
2.
Int J Infect Dis ; 109: 92-98, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34161799

RESUMO

OBJECTIVES: The aim of this study was to determine the contributions of intrauterine (IU), intrapartum (IP), and postpartum (PP) transmission to mother-to-child transmission of HIV-1 (MTCT) and infant mortality in the first 6 months of life, in the era of Option B Plus combination antiretroviral therapy. METHODS: Plasma for virus load (VL) quantitation was obtained from 451 women enrolled into the study. VL was quantified using the Cepheid GeneXpert HIV-1 quantitative test. Dried blood spots were collected from 453 infants at birth, 4-6 weeks, 3 months, and 6 months. HIV-1 infant diagnosis was conducted using the Cepheid GeneXpert HIV-1 qualitative test. Absolute and cumulative MTCT rates, and the mortality rate by 6 months were calculated. RESULTS: Seven mothers (1.55%) had transmitted HIV-1 infection to their infants by 6 months. Four infants (0.88%, 95% confidence interval (CI) 0.26-2.33%) were infected IU, one infant (0.22%, 95% CI 0-1.4%) was infected IP, and two infants (0.44%, 95% CI 0.01-1.7%) were infected PP. The infant mortality rate was 0.88% (95% CI 0.26-2.33%). CONCLUSIONS: In the first 6 months of life, in the era of Option B Plus combination antiretroviral therapy, IU transmission is the major route of MTCT. The cumulative MTCT rate of 1.55% in a breastfeeding population contributes to growing evidence that complete elimination of MTCT is possible.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Complicações Infecciosas na Gravidez , Fármacos Anti-HIV/uso terapêutico , Aleitamento Materno , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico
4.
Lancet Glob Health ; 7(6): e798-e807, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31097281

RESUMO

BACKGROUND: Rapid on-site diagnosis facilitates tuberculosis control. Performing Xpert MTB/RIF (Xpert) at point of care is feasible, even when performed by minimally trained health-care workers, and when compared with point-of-care smear microscopy, reduces time to diagnosis and pretreatment loss to follow-up. However, whether Xpert is cost-effective at point of care remains unclear. METHODS: We empirically collected cost (US$, 2014) and clinical outcome data from participants presenting to primary health-care facilities in four African countries (South Africa, Zambia, Zimbabwe, and Tanzania) during the TB-NEAT trial. Costs were determined using an bottom-up ingredients approach. Effectiveness measures from the trial included number of cases diagnosed, initiated on treatment, and completing treatment. The primary outcome was the incremental cost-effectiveness of point-of-care Xpert relative to smear microscopy. The study was performed from the perspective of the health-care provider. FINDINGS: Using data from 1502 patients, we calculated that the mean Xpert unit cost was lower when performed at a centralised laboratory (Lab Xpert) rather than at point of care ($23·00 [95% CI 22·12-23·88] vs $28·03 [26·19-29·87]). Per 1000 patients screened, and relative to smear microscopy, point-of-care Xpert cost an additional $35 529 (27 054-40 025) and was associated with an additional 24·3 treatment initiations ([-20·0 to 68·5]; $1464 per treatment), 63·4 same-day treatment initiations ([27·3-99·4]; $511 per same-day treatment), and 29·4 treatment completions ([-6·9 to 65·6]; $1211 per completion). Xpert costs were most sensitive to test volume, whereas incremental outcomes were most sensitive to the number of patients initiating and completing treatment. The probability of point-of-care Xpert being cost-effective was 90% at a willingness to pay of $3820 per treatment completion. INTERPRETATION: In southern Africa, although point-of-care Xpert unit cost is higher than Lab Xpert, it is likely to offer good value for money relative to smear microscopy. With the current availability of point-of-care nucleic acid amplification platforms (eg, Xpert Edge), these data inform much needed investment and resource allocation strategies in tuberculosis endemic settings. FUNDING: European Union European and Developing Countries Clinical Trials Partnership.


Assuntos
Técnicas de Amplificação de Ácido Nucleico/métodos , Testes Imediatos , Tuberculose Pulmonar/diagnóstico , Análise Custo-Benefício , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Microscopia/economia , Microscopia/métodos , Técnicas de Amplificação de Ácido Nucleico/economia , Testes Imediatos/economia , África do Sul , Tanzânia , Tuberculose Pulmonar/economia , Zâmbia , Zimbábue
5.
Lancet Glob Health ; 7(2): e191-e199, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30683238

RESUMO

BACKGROUND: Xpert MTB/RIF, the most widely used automated nucleic acid amplification test for tuberculosis, is available in more than 130 countries. Although diagnostic accuracy is well documented, anticipated improvements in patient outcomes have not been clearly identified. We performed an individual patient data meta-analysis to examine improvements in patient outcomes associated with Xpert MTB/RIF. METHODS: We searched PubMed, Embase, ClinicalTrials.gov, and the Pan African Clinical Trials Registry from inception to Feb 1, 2018, for randomised controlled trials (RCTs) comparing the use of Xpert MTB/RIF with sputum smear microscopy as tests for tuberculosis diagnosis in adults (aged 18 years or older). We excluded studies of patients with extrapulmonary tuberculosis, and studies in which mortality was not assessed. We used a two-stage approach for our primary analysis and a one-stage approach for the sensitivity analysis. To assess the primary outcome of cumulative 6-month all-cause mortality, we first performed logistic regression models (random effects for cluster randomised trials, with robust SEs for multicentre studies) for each trial, and then pooled the odds ratio (OR) estimates by a fixed-effects (inverse variance) or random-effects (Der Simonian Laird) meta-analysis. We adjusted for age and gender, and stratified by HIV status and previous tuberculosis-treatment history. The study protocol has been registered with PROSPERO, number CRD42014013394. FINDINGS: Our search identified 387 studies, of which five RCTs were eligible for analysis. 8567 adult clinic attendees (4490 [63·5%] of 7074 participants for whom data were available were HIV-positive) were tested for tuberculosis with Xpert MTB/RIF (Xpert group) versus sputum smear microscopy (sputum smear group), across five low-income and middle-income countries (South Africa, Brazil, Zimbabwe, Zambia, and Tanzania). The primary outcome (reported in three studies) occurred in 182 (4·5%) of 4050 patients in the Xpert group and 217 (5·3%) of 4093 patients in the smear group (pooled adjusted OR 0·88, 95% CI 0·68-1·14 [p=0·34]; for HIV-positive individuals OR 0·83, 0·65-1·05 [p=0·12]). Kaplan-Meier estimates showed a lower rate of death (12·73 per 100 person-years in the Xpert group vs 16·38 per 100 person-years in the sputum smear group) for HIV-positive patients (hazard ratio 0·76, 95% CI 0·60-0·97; p=0·03). The risk of bias was assessed as reasonable and the statistical heterogeneity across studies was low (I2<20% for the primary outcome). INTERPRETATION: Despite individual patient data analysis from five RCTs, we were unable to confidently rule in nor rule out an Xpert MTB/RIF-associated reduction in mortality among outpatients tested for tuberculosis. Reduction in mortality among HIV-positive patients in a secondary analysis suggests the possibility of population-level impact. FUNDING: US National Institutes of Health.


Assuntos
Mycobacterium tuberculosis/genética , Técnicas de Amplificação de Ácido Nucleico , Escarro/microbiologia , Tuberculose Pulmonar/diagnóstico , Adulto , Antituberculosos/uso terapêutico , Brasil/epidemiologia , Causas de Morte , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , Mycobacterium tuberculosis/isolamento & purificação , Razão de Chances , Avaliação de Resultados em Cuidados de Saúde , Modelos de Riscos Proporcionais , África do Sul/epidemiologia , Tanzânia/epidemiologia , Tempo para o Tratamento/estatística & dados numéricos , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/mortalidade , Zâmbia/epidemiologia , Zimbábue/epidemiologia
6.
OMICS ; 23(2): 111-118, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30614763

RESUMO

Past studies on the relationship between Killer cell Immunoglobulin-like Receptor (KIR) and Human Leukocyte Antigen (HLA) genetic variation and chronic immune activation (CIA) in HIV infection are not uniformly consistent. Moreover, interferon-γ-induced protein 10 (IP-10) is a soluble biomarker of immune activation, with high plasma concentrations predicting accelerated disease progression in HIV infection. Thus, we investigated the association of KIR and HLA-C genetic polymorphisms with plasma IP-10 concentration in 183 treatment-naive chronically HIV-infected adults of Bantu origin from Zimbabwe. KIR genetic variation was determined using allele-specific primer PCR while HLA-C typing was characterized by sequencing. Plasma IP-10 was quantified using enzyme-linked immunosorbent assay. The KIR2DL3 gene was significantly associated with CIA as observed from IP-10 concentrations among KIR2DL3 carriers (265.20 pg/mL, IQR: 179.99-385.19) compared with KIR2DL3 noncarriers (183.56 pg/mL; IQR: 110.98-230.81; p = 0.001) and among KIR2DL3+HLA-C2 carriers (226.23 pg/mL, IQR: 187.96-394.73) compared with KIR2DL3+HLA-C2 noncarriers (212.86 pg/mL, IQR: 160.15-344.99; p = 0.017), respectively. Similarly, IP-10 concentrations were significantly higher (p = 0.030) in the KIR3DS1 carriers (313.86 pg/mL, IQR: 230.05-469.20) compared with KIR3DS1 noncarriers (246.01 pg/mL, IQR: 169.58-373.32). Thus, KIR and HLA-C could be playing important roles in HIV-associated immune activation. The elevation of IP-10 in KIR2DL3 and KIR2DL3+C2 could potentially be explained by increased IFN-γ secretion from activated NK cell activation due to the absence of KIR2DL3's cognate C1 ligand. To the best of our knowledge, this is the first study on a potential link between KIR and HLA-C genetic determinants and plasma IP-10 concentration in this population sample. Future studies are called for in other world populations for biomarkers of disease progression and mechanisms of IP-10 variability in HIV infection.


Assuntos
Antirretrovirais/uso terapêutico , Quimiocina CXCL10/sangue , Antígenos HLA-C/genética , Polimorfismo Genético/genética , Receptores KIR/genética , Adulto , Alelos , Biomarcadores/sangue , Feminino , Predisposição Genética para Doença , Genótipo , Infecções por HIV , Humanos , Células Matadoras Naturais/metabolismo , Masculino , Zimbábue
7.
BMC Pulm Med ; 18(1): 67, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29739378

RESUMO

BACKGROUND: The inherent risk of developing tuberculosis (TB) in HIV- infected individuals is further enhanced by hypovitaminosis D. Interventions that offset HIV-associated immune deterioration potentially arrest disease progression and incidence of opportunistic infections including TB. Despite conflicting reports on association between vitamin D deficiency (VDD) and risk of TB, vitamin D (VD) supplementation remains a promising intervention. METHODS: We conducted a comparative cross-sectional study on 145 HIV+/pulmonary TB+ (PTB) and 139 HIV+/PTB- hospitalised patients to investigate association of vitamin D status and risk of PTB. Stratified random sampling was used to select archived serum specimens from participants enrolled in a randomised controlled trial (RCT) conducted to investigate the impact of using a point-of-care urine lipoarabinomannan strip test for TB diagnosis. PTB status was confirmed using sputum smear microscopy, culture or GeneXpert MTB/RIF. Serum 25-hydroxyvitamin D [25(OH) D] concentrations were assayed by competitive chemiluminescent immunoassay prior to commencement of anti-TB treatment. Effect of VD status on duration of hospital stay and patient outcomes on follow up at 8 weeks were also investigated. Median serum 25(OH) D concentrations were compared using Mann-Whitney test and covariates of serum VD status were assessed using logistic regression analysis. RESULTS: Overall VDD prevalence in the cohort was 40.9% (95% CI: 35.1-46.8). Median serum 25(OH)D concentrations were significantly higher in HIV+/PTB+ group (25.3 ng/ml, IQR:18.0-33.7) compared to the HIV+/PTB- group (20.4 ng/ml, IQR:14.6-26.9), p = 0.0003. Patients with serum 25(OH) D concentration ≥ 30 ng/ml were 1.9 times more likely to be PTB+ compared to those with serum 25(OH) D concentrations < 30 ng/ml (odds ratio (OR) 1.91; 95% CI 1.1-3.2). PTB-related death was associated with higher odds of having 25(OH) D levels≥30 ng/ml. Age, gender, CD4+ count, combination antiretroviral therapy (cART) status, efavirenz based cART regimen and length of hospital stay were not associated with vitamin D status. CONCLUSIONS: The finding of an association between higher serum 25(OH) D concentrations and active PTB and TB-related mortality among hospitalised HIV-infected patients in the present study is at variance with the commonly reported association of hypovitaminosis and susceptibility to TB. Our findings though, are in concordance with a small pool of reports from other settings.


Assuntos
Antirretrovirais/uso terapêutico , Infecções por HIV , Tuberculose Pulmonar , Deficiência de Vitamina D , Vitamina D/análogos & derivados , Vitamina D/uso terapêutico , Adulto , Estudos Transversais , Progressão da Doença , Feminino , Infecções por HIV/sangue , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/terapia , Humanos , Incidência , Tempo de Internação/estatística & dados numéricos , Lipopolissacarídeos/análise , Lipopolissacarídeos/urina , Masculino , Infecções Oportunistas/complicações , Fatores de Risco , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/epidemiologia , Urinálise/métodos , Vitamina D/sangue , Deficiência de Vitamina D/diagnóstico , Deficiência de Vitamina D/epidemiologia , Vitaminas/uso terapêutico , Zimbábue/epidemiologia
8.
J Infect Dev Ctries ; 12(12): 1105-1111, 2018 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-32027612

RESUMO

INTRODUCTION: Polymorphisms in killer cell immunoglobulin-like receptor (KIR) and human leukocyte antigen (HLA) gene families are implicated in differential outcomes of HIV infection. However, research findings on the influence of KIR and HLA-C polymorphism on HIV disease progression remain inconclusive. We thus investigated the association of KIR and HLA-C gene polymorphisms with plasma HIV load (VL) and CD4+ T lymphocyte (CD4) count in 183 chronically HIV-infected, combination antiretroviral therapy (cART) naïve Zimbabweans of Bantu origin. METHODOLOGY: The presence or absence of 15 KIR genes were determined using sequence specific primer polymerase chain reaction while HLA-C typing was performed using chain termination DNA sequencing. Plasma VL was determined using the Cavidi Exavir viral load version 3 assay while CD4+ T lymphocytes were enumerated using flow cytometry. VLs and CD4 counts were compared between gene/genotype carriers and non-carriers using Mann-Whitney ranksum test. RESULTS: HLA-C*18:01 allele carriers had a significantly lower median log10 VL (2.87copies/mL [IQR;2.3-3.2]) than the non-C*18:01 carriers (3.33copies/mL [IQR; 2.74-3.9]), p = 0.018. Further, median log10 VL was significantly lower in KIR2DL2+C1 carriers (2.745 [IQR; 2.590-2.745]) than non-KIR2DL2+C1 carriers (3.4 [IQR; 2.746-3.412]), p = 0.041. Comparison of CD4 + T lymphocyte counts between C*08:02 allele carriers and non-C*08:02 carriers showed a significantly higher median CD4 count in C*08:02 carriers (548cells/µL [IQR;410-684]) than in non-carriers (428cells/µL [IQR;388-537]), p = 0.034. CONCLUSION: We conclude that the HLA-C*18:01 and KIR2DL2+C1 genetic variants are associated with low VL while the C*08:02 is associated with high CD4+ T lymphocyte count among cART naïve Zimbabwean adults with chronic HIV infection.


Assuntos
Infecções por HIV/genética , Infecções por HIV/virologia , Antígenos HLA-C/genética , Receptores KIR2DL2/genética , Adulto , Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD4-Positivos/virologia , Estudos Transversais , Frequência do Gene , Infecções por HIV/tratamento farmacológico , Humanos , Polimorfismo Genético , Carga Viral , Zimbábue
9.
Open AIDS J ; 11: 24-31, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28553429

RESUMO

BACKGROUND: Chronic immune activation is a feature of HIV infection associated with accelerated HIV disease progression. There is conflicting data on the association of biomarkers of immune activation with traditional markers of HIV disease progression; CD4 counts and viral load (VL). OBJECTIVE: The study aimed to determine the association of biomarkers of immune activation; interferon (IFN)-γ-induced protein 10 (IP-10) and soluble cluster of differentiation 14 (sCD14) in chronic HIV infection with traditional markers of HIV disease progression. METHODS: We collected demographic data, enumerated CD4 counts and quantified VL in 183 antiretroviral therapy (ART)-naive adults with chronic HIV infection. Plasma concentrations of IP-10 and sCD14 were quantified in the ART-naive adults with chronic HIV infection and 75 HIV-uninfected controls. RESULTS: IP-10 concentrations were significantly higher in the HIV-infected group (median; 257.40pg/ml, IQR; 174.08-376.32) than in the HIV-uninfected (median; 86.19pg/ml, IQR; 67.70-116.39) (P<0.001). Similarly, sCD14 concentrations were significantly higher in the HIV-infected (median; 1.45µg/ml, IQR; 1.02-2.16) group than in the controls (median; 0.89µ/ml, IQR; 0.74-1.18) (P<0.001). High log10 IP-10 concentrations were positively correlated with high log10 viral loads (Spearman's correlation coefficient [R]=0.21, P=0.003) and inversely correlated with low CD4 counts (R= -0.19, P=0.011). In contrast, log10 sCD14 was not significantly associated with either log10 viral loads (R=0.03, P=0.707) nor CD4 count (R=-0.04, P=0.568). CONCLUSION: We conclude that plasma sCD14 and IP-10 were elevated in the HIV-infected patients compared to HIV-uninfected individuals possibly due to on-going immune activation. In addition, plasma high concentrations of IP-10 but not sCD14 concentrations are associated with high VL and low CD4 count.

10.
BMC Infect Dis ; 17(1): 142, 2017 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-28193202

RESUMO

BACKGROUND: There is paucity data on the association of vitamin D deficiency (VDD) and active tuberculosis (TB) in southern Africa where the human immunodeficiency virus (HIV) is co-endemic. We examined the association of serum vitamin D concentrations with active pulmonary tuberculosis (PTB) in HIV-infected (n = 284) and uninfected (n = 267) Black Zimbabweans, in Harare, Zimbabwe. METHODS: We conducted a cross-sectional study of 551 participants comprising 145 HIV+/PTB +, 139 HIV+/PTB-, 134 HIV-/PTB+ and 133 HIV-/PTB-. PTB status was confirmed using sputum by culture, or smear microscopy, or GeneXpert MTB/RIF. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were measured using a competitive chemiluminescent immunoassay prior to commencement of anti-TB treatment. RESULTS: In all four groups, the median vitamin D concentrations were above the 20 ng/ml cut off for VDD. However, the median vitamin D concentrations in all the four groups were below the cut off for vitamin D sufficiency ≥30 ng/ml. The median vitamin D concentrations were significantly higher in PTB+ cases; 24.2 ng/ml (IQR: 18.8-32.0) compared to PTB- controls 20.9 ng/ml (IQR: 17.1-26.9), p < 0.0001 regardless of HIV status. The HIV+/PTB+ group had the highest median vitamin D concentration (25.3 (IQR: 18.0-33.7 ng/ml) whilst the HIV+/PTB- group had the lowest; 20.4 ng/ml (IQR: 14.6-26.9), p = 0.0003. Vitamin D concentration <30 ng/ml was associated with 43% lower odds of being PTB+ OR 0.57 (95% CI 0.35-0.89). CONCLUSIONS: Our results are not in agreement with the generally accepted hypothesis that VDD is associated with active PTB. To the contrary our results showed an association of higher vitamin D concentrations with active TB irrespective of HIV status. Although findings from the available pool of case control studies remain inconsistent, the results from the current study provide further rationale for larger-scale, prospectively designed studies to evaluate whether sufficient vitamin D concentrations do indeed precede the development of active PTB in our setting.


Assuntos
Infecções por HIV/sangue , Tuberculose Pulmonar/sangue , Deficiência de Vitamina D/sangue , Vitamina D/análogos & derivados , Vitamina D/sangue , Vitaminas/uso terapêutico , Adulto , Coinfecção , Estudos Transversais , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Humanos , Masculino , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/epidemiologia , Vitamina D/uso terapêutico , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia , Zimbábue/epidemiologia
11.
Lancet Infect Dis ; 17(4): 441-450, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28063795

RESUMO

BACKGROUND: Inadequate case detection results in high levels of undiagnosed tuberculosis in sub-Saharan Africa. Data for the effect of new diagnostic tools when used for community-based intensified case finding are not available, so we investigated whether the use of sputum Xpert-MTB/RIF and the Determine TB LAM urine test in two African communities could be effective. METHODS: In a pragmatic, randomised, parallel-group trial with individual randomisation stratified by country, we compared sputum Xpert-MTB/RIF, and if HIV-infected, the Determine TB LAM urine test (novel diagnostic group), with laboratory-based sputum smear microscopy (routine diagnostic group) for intensified case finding in communities with high tuberculosis and HIV prevalence in Cape Town, South Africa, and Harare, Zimbabwe. Participants were randomly assigned (1:1) to these groups with computer-generated allocation lists, using culture as the reference standard. In Cape Town, participants were randomised and tested at an Xpert-equipped mobile van, while in Harare, participants were driven to a local clinic where the same diagnostic tests were done. The primary endpoint was the proportion of culture-positive tuberculosis cases initiating tuberculosis treatment in each study group at 60 days. This trial is registered at ClinicalTrials.gov, number NCT01990274. FINDINGS: Between Oct 18, 2013, and March 31, 2015, 2261 individuals were screened and 875 (39%) of these met the criteria for diagnostic testing. 439 participants were randomly assigned to the novel group and 436 to the routine group. 74 (9%) of 875 participants had confirmed tuberculosis. If late culture-based treatment initiation was excluded, more patients with culture-positive tuberculosis were initiated on treatment in the novel group at 60 days (36 [86%] of 42 in the novel group vs 18 [56%] of 32 in the routine group). Thus the difference in the proportion initiating treatment between groups was 29% (95% CI 9-50, p=0·0047) and 53% more patients initiated therapy in the novel diagnostic group than in the routine diagnostic group. One culture-positive patient was treated based only on a positive LAM test. INTERPRETATION: Compared with traditional tools, Xpert-MTB/RIF for community-based intensified case finding in HIV and tuberculosis-endemic settings increased the proportion of patients initiating treatment. By contrast, urine LAM testing was not found to be useful for intensive case finding in this setting. FUNDING: European and Developing Countries Clinical Trials Partnership and South African Medical Research Council.


Assuntos
Instituições de Assistência Ambulatorial , Testes Diagnósticos de Rotina/estatística & dados numéricos , Sensibilidade e Especificidade , Tuberculose/diagnóstico , Adulto , África Subsaariana , Países em Desenvolvimento , Feminino , Humanos , Masculino , Mycobacterium tuberculosis/isolamento & purificação , Prevalência , Escarro , Fatores de Tempo , Tuberculose/terapia , Tuberculose/transmissão
12.
OMICS ; 20(12): 727-735, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27930093

RESUMO

Killer cell immunoglobulin-like receptors (KIRs) mediate natural killer cell function through interaction with their cognate human leukocyte antigen ligands. Thus, KIR gene variants have been implicated in resistance or susceptibility to viral infections. However, research on the role of these variants remains contradictory and inconclusive. In the present study, we investigated KIR gene content diversity and its association with human immunodeficiency virus (HIV) infection in an adult Black Zimbabwean population. Presence or absence of 15 KIR genes was determined in 189 HIV-infected adults and 97 HIV-uninfected blood donors using sequence specific primer polymerase chain reaction. Frequencies of KIR genes, genotypes, and haplotypes were compared between the cases and controls to identify putative associations between KIR gene variants and HIV status. We report in this study the frequencies of 15 KIR genes and 43 KIR genotypes (40 known and 3 novel) among Zimbabweans. Importantly, the frequency of the inhibitory KIR2DL2 gene was significantly higher in the uninfected group (62%) compared to the HIV-infected group (47%) (OR = 0.55, 95% CI: 0.33-0.90, p = 0.019). KIR2DL2/2DL2 homozygosity was also significantly higher in the uninfected group (35%) compared to HIV-infected group (53%) (OR = 0.33, 95% CI: 0.16-0.72, p = 0.005) under a recessive model. We conclude that the KIR2DL2 gene may be involved in protection against HIV infection. It may be possible that inhibitory KIR genes may have an important role to play in HIV acquisition among populations of African origin in whom the activating KIR genes are less frequent compared to among Caucasians.


Assuntos
Predisposição Genética para Doença/genética , Infecções por HIV/genética , Adulto , Feminino , Frequência do Gene/genética , Genótipo , Haplótipos/genética , Humanos , Masculino , Receptores KIR/genética , Zimbábue
13.
Lancet ; 387(10024): 1187-97, 2016 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-26970721

RESUMO

BACKGROUND: HIV-associated tuberculosis is difficult to diagnose and results in high mortality. Frequent extra-pulmonary presentation, inability to obtain sputum, and paucibacillary samples limits the usefulness of nucleic-acid amplification tests and smear microscopy. We therefore assessed a urine-based, lateral flow, point-of-care, lipoarabinomannan assay (LAM) and the effect of a LAM-guided anti-tuberculosis treatment initiation strategy on mortality. METHODS: We did a pragmatic, randomised, parallel-group, multicentre trial in ten hospitals in Africa--four in South Africa, two in Tanzania, two in Zambia, and two in Zimbabwe. Eligible patients were HIV-positive adults aged at least 18 years with at least one of the following symptoms of tuberculosis (fever, cough, night sweats, or self-reported weightloss) and illness severity necessitating admission to hospital. Exclusion criteria included receipt of any anti-tuberculosis medicine in the 60 days before enrolment. We randomly assigned patients (1:1) to either LAM plus routine diagnostic tests for tuberculosis (smear microscopy, Xpert-MTB/RIF, and culture; LAM group) or routine diagnostic tests alone (no LAM group) using computer-generated allocation lists in blocks of ten. All patients were asked to provide a urine sample of at least 30 mL at enrolment, and trained research nurses did the LAM test in patients allocated to this group using the Alere Determine tuberculosis LAM Ag lateral flow strip test (Alere, USA) at the bedside on enrolment. On the basis of a positive test result, the nurses made a recommendation for initiating anti-tuberculosis treatment. The attending physician made an independent decision about whether to start treatment or not. Neither patients nor health-care workers were masked to group allocation and test results. The primary endpoint was 8-week all-cause mortality assessed in the modified intention-to-treat population (those who received their allocated intervention). This trial is registered with ClinicalTrials.gov, number NCT01770730. FINDINGS: Between Jan 1, 2013, and Oct 2, 2014, we screened 8728 patients and randomly assigned 2659 to treatment (1336 to LAM, 1323 to no LAM). 108 patients did not receive their allocated treatment, mainly because they did not meet the inclusion criteria, and 23 were excluded from analysis, leaving 2528 in the final modified intention-to-treat analysis (1257 in the LAM group, 1271 in the no LAM group). Overall all-cause 8-week mortality occurred in 578 (23%) patients, 261 (21%) in LAM and 317 (25%) in no LAM, an absolute reduction of 4% (95% CI 1-7). The risk ratio adjusted for country was 0·83 (95% CI 0·73-0·96), p=0·012, with a relative risk reduction of 17% (95% CI 4-28). With the time-to-event analysis, there were 159 deaths per 100 person-years in LAM and 196 per 100 person-years in no LAM (hazard ratio adjusted for country 0·82 [95% CI 0·70-0·96], p=0·015). No adverse events were associated with LAM testing. INTERPRETATION: Bedside LAM-guided initiation of anti-tuberculosis treatment in HIV-positive hospital inpatients with suspected tuberculosis was associated with reduced 8-week mortality. The implementation of LAM testing is likely to offer the greatest benefit in hospitals where diagnostic resources are most scarce and where patients present with severe illness, advanced immunosuppression, and an inability to self-expectorate sputum. FUNDING: European Developing Clinical Trials Partnership, the South African Medical Research Council, and the South African National Research Foundation.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Lipopolissacarídeos/urina , Sistemas Automatizados de Assistência Junto ao Leito , Tuberculose/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Adulto , África/epidemiologia , Antituberculosos/uso terapêutico , Biomarcadores/urina , Contagem de Linfócito CD4 , Testes Diagnósticos de Rotina , Feminino , Hospitalização , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Sensibilidade e Especificidade , Resultado do Tratamento , Tuberculose/tratamento farmacológico , Tuberculose/imunologia , Tuberculose/mortalidade
14.
BMC Infect Dis ; 16: 20, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26797499

RESUMO

BACKGROUND: In Zimbabwe, sputum smear microscopy (SSM) is the routinely used TB diagnostic tool in hospitalised HIV-infected patients. However, SSM has poor sensitivity in HIV-infected patients. We compared performance of urine lipoarabinomannan strip test (LAM) and SSM among hospitalized HIV-infected patients with suspected TB. METHODS: Hospitalized HIV-infected patients with suspected TB were randomized to LAM plus SSM or SSM alone groups as part of a larger multi-country parent study. Here we present a comparison of LAM versus SSM performance from the Zimbabwe study site. LAM analyses (grade 2 cut-off) were conducted using (i) a microbiological reference standard (MRS; culture positivity for M.tb and designated definite TB) and (ii) a composite reference standard (CRS; definite TB plus probable TB i.e. patients with clinical TB excluded from the culture negative group). CRS constituted the primary analysis. RESULTS: 82/457 (18%) of the patients randomized to the LAM group were M.tuberculosis culture positive. Using CRS, sensitivity (%, 95% CI) of LAM was significantly higher than SSM [49.2 (42.1-56.4) versus 29.4(23.2-36.3); p < 0.001]. Specificity and PPV were 98.1%, and 95.8%, respectively. By contrast, using MRS, LAM sensitivity was similar to SSM and specificity was significantly lower, however, the combined sensitivity of LAM and SSM was significantly higher than that of SSM alone, p = 0.009. Using CRS, LAM sensitivity (%, CI) was CD4 count dependent [60.6(50.7-69.8) at ≤50 cells/µL; 40.0(22.7-59.4) at 51-100 cells/µL, and 32.8(21.0-46.3) at >100 cells/µL. The combined sensitivity of LAM and SSM was higher than SSM alone being highest at CD4 counts <50 cells/µL [67.6(57.9-76.3); p = <0.001]. Specificity of LAM or SSM alone, or of combined LAM and SSM was >97% in all the 3 CD4 strata. CONCLUSION: Among hospitalized HIV-infected patients with suspected TB, the sensitivity of LAM is significantly higher than that of SSM, especially at low CD4 counts. LAM and SSM are complimentary tests for diagnosis of TB in HIV-infected patients. We recommend a combination of LAM and SSM for TB diagnosis in HIV-infected patients with low CD4 counts in HIV/TB co-endemic countries, where alternative methods are unavailable.


Assuntos
Infecções por HIV/complicações , Lipopolissacarídeos/urina , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Tuberculose/diagnóstico , Adulto , Feminino , Humanos , Masculino , Microscopia , Pessoa de Meia-Idade , Mycobacterium tuberculosis/fisiologia , Sensibilidade e Especificidade , Tuberculose/etiologia , Tuberculose/microbiologia , Zimbábue/epidemiologia
15.
BMC Infect Dis ; 15: 253, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26126655

RESUMO

BACKGROUND: The successful cure of tuberculosis (TB) is dependent on adherence to treatment. Various factors influence adherence, however, few are easily modifiable. There are limited data regarding correlates of psychological distress and their association with non-adherence to anti-TB treatment. METHODS: In a trial of a new TB test, we measured psychological distress (K-10 score), TB-related health literacy, and morbidity (TBscore), prior to diagnosis in 1502 patients with symptoms of pulmonary TB recruited from clinics in Cape Town (n = 419), Harare (n = 400), Lusaka (n = 400), Durban (n = 200), and Mbeya (n = 83). Socioeconomic, demographic, and alcohol usage-related data were captured. Patients initiated on treatment had their DOTS cards reviewed at two-and six-months. RESULTS: 22 %(95 % CI: 20 %, 25 %) of patients had severe psychological distress (K-10 ≥ 30). In a multivariable linear regression model, increased K-10 score was independently associated with previous TB [estimate (95 % CI) 0.98(0.09-1.87); p = 0.0304], increased TBscore [1(0.80, 1.20); p <0.0001], and heavy alcohol use [3.08(1.26, 4.91); p = 0.0010], whereas male gender was protective [-1.47(-2.28, -0.62); p = 0.0007]. 26 % (95 % CI: 21 %, 32 %) of 261 patients with culture-confirmed TB were non-adherent. In a multivariable logistic regression model for non-adherence, reduced TBscore [OR (95 % CI) 0.639 (0.497, 0.797); p = 0.0001], health literacy score [0.798(0.696, 0.906); p = 0.0008], and increased K-10 [1.082(1.033, 1.137); p = 0.0012], and heavy alcohol usage [14.83(2.083, 122.9); p = 0.0002], were independently associated. Culture-positive patients with a K-10 score ≥ 30 were more-likely to be non-adherent (OR = 2.290(1.033-5.126); p = 0.0416]. CONCLUSION: Severe psychological distress is frequent amongst TB patients in Southern Africa. Targeted interventions to alleviate psychological distress, alcohol use, and improve health literacy in newly-diagnosed TB patients could reduce non-adherence to treatment.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Antituberculosos/uso terapêutico , Adesão à Medicação/estatística & dados numéricos , Estresse Psicológico/epidemiologia , Tuberculose Pulmonar/tratamento farmacológico , Adulto , Consumo de Bebidas Alcoólicas/psicologia , Ansiedade/epidemiologia , Ansiedade/psicologia , Depressão/epidemiologia , Depressão/psicologia , Feminino , Humanos , Modelos Logísticos , Masculino , Adesão à Medicação/psicologia , Pessoa de Meia-Idade , Análise Multivariada , Fatores Sexuais , África do Sul/epidemiologia , Estresse Psicológico/psicologia , Tanzânia/epidemiologia , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/psicologia , Zâmbia/epidemiologia , Zimbábue/epidemiologia
16.
Lancet ; 383(9915): 424-35, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24176144

RESUMO

BACKGROUND: The Xpert MTB/RIF test for tuberculosis is being rolled out in many countries, but evidence is lacking regarding its implementation outside laboratories, ability to inform same-day treatment decisions at the point of care, and clinical effect on tuberculosis-related morbidity. We aimed to assess the feasibility, accuracy, and clinical effect of point-of-care Xpert MTB/RIF testing at primary-care health-care facilities in southern Africa. METHODS: In this pragmatic, randomised, parallel-group, multicentre trial, we recruited adults with symptoms suggestive of active tuberculosis from five primary-care health-care facilities in South Africa, Zimbabwe, Zambia, and Tanzania. Eligible patients were randomly assigned using pregenerated tables to nurse-performed Xpert MTB/RIF at the clinic or sputum smear microscopy. Participants with a negative test result were empirically managed according to local WHO-compliant guidelines. Our primary outcome was tuberculosis-related morbidity (measured with the TBscore and Karnofsky performance score [KPS]) in culture-positive patients who had begun anti-tuberculosis treatment, measured at 2 months and 6 months after randomisation, analysed by intention to treat. This trial is registered with Clinicaltrials.gov, number NCT01554384. FINDINGS: Between April 12, 2011, and March 30, 2012, we randomly assigned 758 patients to smear microscopy (182 culture positive) and 744 to Xpert MTB/RIF (185 culture positive). Median TBscore in culture-positive patients did not differ between groups at 2 months (2 [IQR 0-3] in the smear microscopy group vs 2 [0·25-3] in the MTB/RIF group; p=0·85) or 6 months (1 [0-3] vs 1 [0-3]; p=0·35), nor did median KPS at 2 months (80 [70-90] vs 90 [80-90]; p=0·23) or 6 months (100 [90-100] vs 100 [90-100]; p=0·85). Point-of-care MTB/RIF had higher sensitivity than microscopy (154 [83%] of 185 vs 91 [50%] of 182; p=0·0001) but similar specificity (517 [95%] 544 vs 540 [96%] of 560; p=0·25), and had similar sensitivity to laboratory-based MTB/RIF (292 [83%] of 351; p=0·99) but higher specificity (952 [92%] of 1037; p=0·0173). 34 (5%) of 744 tests with point-of-care MTB/RIF and 82 (6%) of 1411 with laboratory-based MTB/RIF failed (p=0·22). Compared with the microscopy group, more patients in the MTB/RIF group had a same-day diagnosis (178 [24%] of 744 vs 99 [13%] of 758; p<0·0001) and same-day treatment initiation (168 [23%] of 744 vs 115 [15%] of 758; p=0·0002). Although, by end of the study, more culture-positive patients in the MTB/RIF group were on treatment due to reduced dropout (15 [8%] of 185 in the MTB/RIF group did not receive treatment vs 28 [15%] of 182 in the microscopy group; p=0·0302), the proportions of all patients on treatment in each group by day 56 were similar (320 [43%] of 744 in the MTB/RIF group vs 317 [42%] of 758 in the microscopy group; p=0·6408). INTERPRETATION: Xpert MTB/RIF can be accurately administered by a nurse in primary-care clinics, resulting in more patients starting same-day treatment, more culture-positive patients starting therapy, and a shorter time to treatment. However, the benefits did not translate into lower tuberculosis-related morbidity, partly because of high levels of empirical-evidence-based treatment in smear-negative patients. FUNDING: European and Developing Countries Clinical Trials Partnership, National Research Foundation, and Claude Leon Foundation.


Assuntos
Sistemas Automatizados de Assistência Junto ao Leito/normas , Tuberculose Pulmonar/diagnóstico , Adulto , África , Técnicas Bacteriológicas/normas , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde , Escarro/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/enfermagem , Tuberculose Pulmonar/enfermagem
17.
Lancet Infect Dis ; 13(4): 349-61, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23531388

RESUMO

Rapid progress has been made in the development of new diagnostic assays for tuberculosis in recent years. New technologies have been developed and assessed, and are now being implemented. The Xpert MTB/RIF assay, which enables simultaneous detection of Mycobacterium tuberculosis (MTB) and rifampicin (RIF) resistance, was endorsed by WHO in December, 2010. This assay was specifically recommended for use as the initial diagnostic test for suspected drug-resistant or HIV-associated pulmonary tuberculosis. By June, 2012, two-thirds of countries with a high tuberculosis burden and half of countries with a high multidrug-resistant tuberculosis burden had incorporated the assay into their national tuberculosis programme guidelines. Although the development of the Xpert MTB/RIF assay is undoubtedly a landmark event, clinical and programmatic effects and cost-effectiveness remain to be defined. We review the rapidly growing body of scientific literature and discuss the advantages and challenges of using the Xpert MTB/RIF assay in areas where tuberculosis is endemic. We also review other prospects within the developmental pipeline. A rapid, accurate point-of-care diagnostic test that is affordable and can be readily implemented is urgently needed. Investment in the tuberculosis diagnostics pipeline should remain a major priority for funders and researchers.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Antibióticos Antituberculose , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Sistemas Automatizados de Assistência Junto ao Leito , Rifampina , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Efeitos Psicossociais da Doença , Análise Custo-Benefício , Farmacorresistência Bacteriana , Saúde Global , Custos de Cuidados de Saúde , Humanos , Mycobacterium tuberculosis/genética , Técnicas de Amplificação de Ácido Nucleico , Sistemas Automatizados de Assistência Junto ao Leito/tendências , Valor Preditivo dos Testes , Escarro/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/mortalidade , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/epidemiologia
18.
Lancet Infect Dis ; 13(6): 529-39, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23531391

RESUMO

Two decades ago, WHO declared tuberculosis a global emergency, and invested in the highly cost-effective directly observed treatment short-course programme to control the epidemic. At that time, most strains of Mycobacterium tuberculosis were susceptible to first-line tuberculosis drugs, and drug resistance was not a major issue. However, in 2013, tuberculosis remains a major public health concern worldwide, with prevalence of multidrug-resistant (MDR) tuberculosis rising. WHO estimates roughly 630 000 cases of MDR tuberculosis worldwide, with great variation in the frequency of MDR tuberculosis between countries. In the past 8 years, extensively drug-resistant (XDR) tuberculosis has emerged, and has been reported in 84 countries, heralding the possibility of virtually untreatable tuberculosis. Increased population movement, the continuing HIV pandemic, and the rise in MDR tuberculosis pose formidable challenges to the global control of tuberculosis. We provide an overview of the global burden of drug-resistant disease; discuss the social, health service, management, and control issues that fuel and sustain the epidemic; and suggest specific recommendations for important next steps. Visionary political leadership is needed to curb the rise of MDR and XDR tuberculosis worldwide, through sustained funding and the implementation of global and regional action plans.


Assuntos
Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Antituberculosos/uso terapêutico , Saúde Global , Humanos , Prevalência , Organização Mundial da Saúde
19.
Lancet Infect Dis ; 13(5): 436-48, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23531392

RESUMO

Recent data for the global burden of disease reflect major demographic and lifestyle changes, leading to a rise in non-communicable diseases. Most countries with high levels of tuberculosis face a large comorbidity burden from both non-communicable and communicable diseases. Traditional disease-specific approaches typically fail to recognise common features and potential synergies in integration of care, management, and control of non-communicable and communicable diseases. In resource-limited countries, the need to tackle a broader range of overlapping comorbid diseases is growing. Tuberculosis and HIV/AIDS persist as global emergencies. The lethal interaction between tuberculosis and HIV coinfection in adults, children, and pregnant women in sub-Saharan Africa exemplifies the need for well integrated approaches to disease management and control. Furthermore, links between diabetes mellitus, smoking, alcoholism, chronic lung diseases, cancer, immunosuppressive treatment, malnutrition, and tuberculosis are well recognised. Here, we focus on interactions, synergies, and challenges of integration of tuberculosis care with management strategies for non-communicable and communicable diseases without eroding the functionality of existing national programmes for tuberculosis. The need for sustained and increased funding for these initiatives is greater than ever and requires increased political and funder commitment.


Assuntos
Controle de Doenças Transmissíveis/organização & administração , Tuberculose/epidemiologia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Coinfecção/epidemiologia , Controle de Doenças Transmissíveis/métodos , Doenças Transmissíveis/epidemiologia , Comorbidade , Diabetes Mellitus/epidemiologia , Saúde Global , Necessidades e Demandas de Serviços de Saúde/organização & administração , Humanos , Mycobacterium tuberculosis/patogenicidade , Programas Nacionais de Saúde/economia , Programas Nacionais de Saúde/organização & administração , Fatores de Risco , Fatores Socioeconômicos , Tuberculose/microbiologia , Tuberculose/prevenção & controle
20.
J AIDS Clin Res ; 3(2): 141-147, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23019537

RESUMO

INTRODUCTION: Drug resistance mutations (DRM) in viral RNA are important in defining to provide effective antiretroviral therapy (ART) in HIV-1 infected patients. Detection of DRM in peripheral blood mononuclear cell (PBMC) DNA is another source of information, although the clinical significance of DRMs in proviral DNA is less clear. MATERIALS AND METHODS: From 25 patients receiving ART at a center in Zimbabwe, 32 blood samples were collected. Dideoxy-sequencing of gag-pol identified subtype and resistance mutations from plasma viral RNA and proviral DNA. Drug resistance was estimated using the calibrated population resistance tool on www.hivdb.stanford.edu database. Numerical resistance scores were calculated for all antiretroviral drugs and for the subjects' reported regimen. Phylogenetic analysis as maximum likelihood was performed to determine the evolutionary distance between sequences. RESULTS: Of the 25 patients, 4 patients (2 of which had given 2 blood samples) were not known to be on ART (NA) and had exclusively wild-type virus, 17 had received Protease inhibitors (PI), 18, non-nucleoside reverse transcriptase inhibitors (NNRTI) and 19, two or more nucleoside reverse transcriptase inhibitors (NRTI). Of the 17 with history of PI, 10 had PI mutations, 5 had minor differences between mutations in RNA and DNA. Eighteen samples had NNRTI mutations, six of which demonstrated some discordance between DNA and RNA mutations. Although NRTI resistance mutations were frequently different between analyses, mutations resulted in very similar estimated phenotypes as measured by resistance scores. The numerical resistance scores from RNA and DNA for PIs differed between 2/10, for NNRTIs between 8/18, and for NRTIs between 17/32 pairs. When calculated resistance scores were collapsed, 3 pairs showed discordance between RNA and DNA for at least one PI, 6 were discordant for at least one NNRTI and 11 for at least one NRTI. Regarding phylogenetic evolutionary analysis, all RNA and DNA sequence pairs clustered closely in a maximum likelihood tree. CONCLUSION: PBMC DNA could be useful for testing drug resistance in conjunction with plasma RNA where the results of each yielded complementary information about drug resistance. Identification of DRM, archived in proviral DNA, could be used to provide for sustainable public health surveillance among subtype C infected patients.

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