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1.
AIDS Res Ther ; 19(1): 10, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35193598

RESUMO

BACKGROUND: Zambia recently achieved UNAIDS 90-90-90 treatment targets for HIV epidemic control; however, inpatient facilities continue to face a large burden of patients with advanced HIV disease and HIV-related mortality. Management of advanced HIV disease, following guidelines from outpatient settings, may be more difficult within complex inpatient settings. We evaluated adherence to HIV guidelines during hospitalization, including opportunistic infection (OI) screening, treatment, and prophylaxis. METHODS: We reviewed inpatient medical records of people living with HIV (PLHIV) admitted to the University Teaching Hospital in Lusaka, Zambia between December 1, 2018 and April 30, 2019. We collected data on patient demographics, antiretroviral therapy (ART), HIV biomarkers, and OI screening and treatment-including tuberculosis (TB), Cryptococcus, and OI prophylaxis with co-trimoxazole (CTX). Screening and treatment cascades were constructed based on the 2017 WHO Advanced HIV Guidelines. RESULTS: We reviewed files from 200 charts of patients with advanced HIV disease; of these 92% (184/200) had been on ART previously; 58.1% (107/184) for more than 12 months. HIV viral load (VL) testing was uncommon but half of VL results were high. 39% (77/200) of patients had a documented CD4 count result. Of the 172 patients not on anti-TB treatment (ATT) on admission, TB diagnostic tests (either sputum Xpert MTB/RIF MTB/RIF or urine TB-LAM) were requested for 105 (61%) and resulted for 60 of the 105 (57%). Nine of the 14 patients (64%) with a positive lab result for TB died before results were available. Testing for Cryptococcosis was performed predominantly in patients with symptoms of meningitis. Urine TB-LAM testing was rarely performed. CONCLUSIONS: At a referral hospital in Zambia, CD4 testing was inconsistent due to laboratory challenges and this reduced recognition of AHD and implementation of AHD guidelines. HIV programs can potentially reduce mortality and identify PLHIV with retention and adherence issues through strengthening inpatient activities, including reflex VL testing, TB-LAM and serum CrAg during hospitalization.


Assuntos
Infecções por HIV , Tuberculose , Gerenciamento Clínico , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Hospitais , Humanos , Pacientes Internados , Encaminhamento e Consulta , Estudos Retrospectivos , Sensibilidade e Especificidade , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Zâmbia/epidemiologia
2.
N Engl J Med ; 378(11): 1004-1017, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29539274

RESUMO

BACKGROUND: Cryptococcal meningitis accounts for more than 100,000 human immunodeficiency virus (HIV)-related deaths per year. We tested two treatment strategies that could be more sustainable in Africa than the standard of 2 weeks of amphotericin B plus flucytosine and more effective than the widely used fluconazole monotherapy. METHODS: We randomly assigned HIV-infected adults with cryptococcal meningitis to receive an oral regimen (fluconazole [1200 mg per day] plus flucytosine [100 mg per kilogram of body weight per day] for 2 weeks), 1 week of amphotericin B (1 mg per kilogram per day), or 2 weeks of amphotericin B (1 mg per kilogram per day). Each patient assigned to receive amphotericin B was also randomly assigned to receive fluconazole or flucytosine as a partner drug. After induction treatment, all the patients received fluconazole consolidation therapy and were followed to 10 weeks. RESULTS: A total of 721 patients underwent randomization. Mortality in the oral-regimen, 1-week amphotericin B, and 2-week amphotericin B groups was 18.2% (41 of 225), 21.9% (49 of 224), and 21.4% (49 of 229), respectively, at 2 weeks and was 35.1% (79 of 225), 36.2% (81 of 224), and 39.7% (91 of 229), respectively, at 10 weeks. The upper limit of the one-sided 97.5% confidence interval for the difference in 2-week mortality was 4.2 percentage points for the oral-regimen group versus the 2-week amphotericin B groups and 8.1 percentage points for the 1-week amphotericin B groups versus the 2-week amphotericin B groups, both of which were below the predefined 10-percentage-point noninferiority margin. As a partner drug with amphotericin B, flucytosine was superior to fluconazole (71 deaths [31.1%] vs. 101 deaths [45.0%]; hazard ratio for death at 10 weeks, 0.62; 95% confidence interval [CI], 0.45 to 0.84; P=0.002). One week of amphotericin B plus flucytosine was associated with the lowest 10-week mortality (24.2%; 95% CI, 16.2 to 32.1). Side effects, such as severe anemia, were more frequent with 2 weeks than with 1 week of amphotericin B or with the oral regimen. CONCLUSIONS: One week of amphotericin B plus flucytosine and 2 weeks of fluconazole plus flucytosine were effective as induction therapy for cryptococcal meningitis in resource-limited settings. (ACTA Current Controlled Trials number, ISRCTN45035509 .).


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Anfotericina B/administração & dosagem , Antifúngicos/uso terapêutico , Fluconazol/administração & dosagem , Flucitosina/administração & dosagem , Meningite Criptocócica/tratamento farmacológico , Administração Oral , Adulto , África/epidemiologia , Anfotericina B/efeitos adversos , Antifúngicos/efeitos adversos , Esquema de Medicação , Quimioterapia Combinada , Feminino , Fluconazol/efeitos adversos , Flucitosina/efeitos adversos , Soropositividade para HIV/complicações , Humanos , Estimativa de Kaplan-Meier , Masculino , Meningite Criptocócica/mortalidade , Modelos de Riscos Proporcionais
3.
Clin Infect Dis ; 70(1): 26-29, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30816418

RESUMO

BACKGROUND: Mortality from cryptococcal meningitis remains very high in Africa. In the Advancing Cryptococcal Meningitis Treatment for Africa (ACTA) trial, 2 weeks of fluconazole (FLU) plus flucytosine (5FC) was as effective and less costly than 2 weeks of amphotericin-based regimens. However, many African settings treat with FLU monotherapy, and the cost-effectiveness of adding 5FC to FLU is uncertain. METHODS: The effectiveness and costs of FLU+5FC were taken from ACTA, which included a costing analysis at the Zambian site. The effectiveness of FLU was derived from cohorts of consecutively enrolled patients, managed in respects other than drug therapy, as were participants in ACTA. FLU costs were derived from costs of FLU+5FC in ACTA, by subtracting 5FC drug and monitoring costs. The cost-effectiveness of FLU+5FC vs FLU alone was measured as the incremental cost-effectiveness ratio (ICER). A probabilistic sensitivity analysis assessed uncertainties and a bivariate deterministic sensitivity analysis examined the impact of varying mortality and 5FC drug costs on the ICER. RESULTS: The mean costs per patient were US $847 (95% confidence interval [CI] $776-927) for FLU+5FC, and US $628 (95% CI $557-709) for FLU. The 10-week mortality rate was 35.1% (95% CI 28.9-41.7%) with FLU+5FC and 53.8% (95% CI 43.1-64.1%) with FLU. At the current 5FC price of US $1.30 per 500 mg tablet, the ICER of 5FC+FLU versus FLU alone was US $65 (95% CI $28-208) per life-year saved. Reducing the 5FC cost to between US $0.80 and US $0.40 per 500 mg resulted in an ICER between US $44 and US $28 per life-year saved. CONCLUSIONS: The addition of 5FC to FLU is cost-effective for cryptococcal meningitis treatment in Africa and, if made available widely, could substantially reduce mortality rates among human immunodeficiency virus-infected persons in Africa.


Assuntos
Flucitosina , Meningite Criptocócica , África , Antifúngicos/uso terapêutico , Análise Custo-Benefício , Fluconazol/uso terapêutico , Flucitosina/uso terapêutico , Humanos , Meningite Criptocócica/tratamento farmacológico
4.
J Infect Dis ; 220(3): 432-441, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-30938435

RESUMO

Few human immunodeficiency virus (HIV)-infected persons can maintain low viral levels without therapeutic intervention. We evaluate predictors of spontaneous control of the viral load (hereafter, "viral control") in a prospective cohort of African adults shortly after HIV infection. Viral control was defined as ≥2 consecutively measured viral loads (VLs) of ≤10 000 copies/mL after the estimated date of infection, followed by at least 4 subsequent measurements for which the VL in at least 75% was ≤10 000 copies/mL in the absence of ART. Multivariable logistic regression characterized predictors of viral control. Of 590 eligible volunteers, 107 (18.1%) experienced viral control, of whom 25 (4.2%) maintained a VL of 51-2000 copies/mL, and 5 (0.8%) sustained a VL of ≤50 copies/mL. The median ART-free follow-up time was 3.3 years (range, 0.3-9.7 years). Factors independently associated with control were HIV-1 subtype A (reference, subtype C; adjusted odds ratio [aOR], 2.1 [95% confidence interval {CI}, 1.3-3.5]), female sex (reference, male sex; aOR, 1.8 [95% CI, 1.1-2.8]), and having HLA class I variant allele B*57 (reference, not having this allele; aOR, 1.9 [95% CI, 1.0-3.6]) in a multivariable model that also controlled for age at the time of infection and baseline CD4+ T-cell count. We observed strong associations between infecting HIV-1 subtype, HLA type, and sex on viral control in this cohort. HIV-1 subtype is important to consider when testing and designing new therapeutic and prevention technologies, including vaccines.

5.
Clin Infect Dis ; 69(4): 588-595, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30863852

RESUMO

BACKGROUND: Mortality from cryptoccocal meningitis remains high. The ACTA trial demonstrated that, compared with 2 weeks of amphotericin B (AmB) plus flucystosine (5FC), 1 week of AmB and 5FC was associated with lower mortality and 2 weeks of oral flucanozole (FLU) plus 5FC was non-inferior. Here, we assess the cost-effectiveness of these different treatment courses. METHODS: Participants were randomized in a ratio of 2:1:1:1:1 to 2 weeks of oral 5FC and FLU, 1 week of AmB and FLU, 1 week of AmB and 5FC, 2 weeks of AmB and FLU, or 2 weeks of AmB and 5FC in Malawi, Zambia, Cameroon, and Tanzania. Data on individual resource use and health outcomes were collected. Cost-effectiveness was measured as incremental costs per life-year saved, and non-parametric bootstrapping was done. RESULTS: Total costs per patient were US $1442 for 2 weeks of oral FLU and 5FC, $1763 for 1 week of AmB and FLU, $1861 for 1 week of AmB and 5FC, $2125 for 2 weeks of AmB and FLU, and $2285 for 2 weeks of AmB and 5FC. Compared to 2 weeks of AmB and 5FC, 1 week of AmB and 5FC was less costly and more effective and 2 weeks of oral FLU and 5FC was less costly and as effective. The incremental cost-effectiveness ratio for 1 week of AmB and 5FC versus oral FLU and 5FC was US $208 (95% confidence interval $91-1210) per life-year saved. CLINICAL TRIALS REGISTRATION: ISRCTN45035509. CONCLUSIONS: Both 1 week of AmB and 5FC and 2 weeks of Oral FLU and 5FC are cost-effective treatments.


Assuntos
Antifúngicos , Meningite Criptocócica , África Subsaariana , Antifúngicos/economia , Antifúngicos/uso terapêutico , Flucitosina/economia , Flucitosina/uso terapêutico , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Meningite Criptocócica/diagnóstico , Meningite Criptocócica/economia , Meningite Criptocócica/epidemiologia , Meningite Criptocócica/terapia
6.
J Neurovirol ; 25(4): 475-479, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31028690

RESUMO

There are only few documented cases of progressive multifocal leukoencephalopathy (PML) in Africa. Whether this is caused by a lack of JC virus (JCV) spread or alteration in the JCV genome is unknown. We characterized the clinical presentation, laboratory findings, and JCV regulatory region (RR) pattern of the first documented PML cases in Zambia as well as JCV seroprevalence among HIV+ and HIV- Zambians. We identified PML patients with positive JCV DNA PCR in their cerebrospinal fluid (CSF) among subjects enrolled in an ongoing tuberculous meningitis study from 2014 to 2016 in Lusaka. JCV regulatory region was further characterized by duplex PCR in patients' urine and CSF. Of 440 HIV+ patients, 14 (3%) had detectable JCV DNA in their CSF (age 18-50; CD4+ T cells counts 15-155 × 106/µl) vs 0/60 HIV- patients. The main clinical manifestations included altered mental status and impaired consciousness consistent with advanced PML. While prototype JCV was identified by duplex PCR assay in the CSF samples of all 14 PML patients, only archetype JCV was detected in their urine. All PML Zambian patients tested were seropositive for JCV compared to 46% in a control group of HIV+ and HIV- Zambian patients without PML. PML occurs among HIV-infected individuals in Zambia and is caused by CNS infection with prototype JCV, while archetype JCV strains are present in their urine. JCV seroprevalence is comparable in Zambia and the USA, and PML should be included in the differential diagnosis of immunosuppressed individuals presenting with neurological dysfunction in Zambia.


Assuntos
DNA Viral/genética , Infecções por Henipavirus/diagnóstico , Vírus JC/genética , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Tuberculose Meníngea/diagnóstico , Adolescente , Adulto , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/virologia , Estudos de Casos e Controles , Coinfecção , DNA Viral/líquido cefalorraquidiano , DNA Viral/urina , Feminino , Genótipo , HIV/efeitos dos fármacos , HIV/genética , HIV/isolamento & purificação , Infecções por Henipavirus/líquido cefalorraquidiano , Infecções por Henipavirus/tratamento farmacológico , Infecções por Henipavirus/virologia , Humanos , Vírus JC/efeitos dos fármacos , Vírus JC/isolamento & purificação , Leucoencefalopatia Multifocal Progressiva/líquido cefalorraquidiano , Leucoencefalopatia Multifocal Progressiva/tratamento farmacológico , Leucoencefalopatia Multifocal Progressiva/virologia , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Tuberculose Meníngea/líquido cefalorraquidiano , Tuberculose Meníngea/tratamento farmacológico , Tuberculose Meníngea/virologia , Zâmbia
7.
PLoS Pathog ; 12(11): e1005989, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27851829

RESUMO

A recent study of plasma neutralization breadth in HIV-1 infected individuals at nine International AIDS Vaccine Initiative (IAVI) sites reported that viral load, HLA-A*03 genotype, and subtype C infection were strongly associated with the development of neutralization breadth. Here, we refine the findings of that study by analyzing the impact of the transmitted/founder (T/F) envelope (Env), early Env diversification, and autologous neutralization on the development of plasma neutralization breadth in 21 participants identified during recent infection at two of those sites: Kigali, Rwanda (n = 9) and Lusaka, Zambia (n = 12). Single-genome analysis of full-length T/F Env sequences revealed that all 21 individuals were infected with a highly homogeneous population of viral variants, which were categorized as subtype C (n = 12), A1 (n = 7), or recombinant AC (n = 2). An extensive amino acid sequence-based analysis of variable loop lengths and glycosylation patterns in the T/F Envs revealed that a lower ratio of NXS to NXT-encoded glycan motifs correlated with neutralization breadth. Further analysis comparing amino acid sequence changes, insertions/deletions, and glycan motif alterations between the T/F Env and autologous early Env variants revealed that extensive diversification focused in the V2, V4, and V5 regions of gp120, accompanied by contemporaneous viral escape, significantly favored the development of breadth. These results suggest that more efficient glycosylation of subtype A and C T/F Envs through fewer NXS-encoded glycan sites is more likely to elicit antibodies that can transition from autologous to heterologous neutralizing activity following exposure to gp120 diversification. This initiates an Env-antibody co-evolution cycle that increases neutralization breadth, and is further augmented over time by additional viral and host factors. These findings suggest that understanding how variation in the efficiency of site-specific glycosylation influences neutralizing antibody elicitation and targeting could advance the design of immunogens aimed at inducing antibodies that can transition from autologous to heterologous neutralizing activity.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Infecções por HIV/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo , Anticorpos Neutralizantes/sangue , Glicosilação , Anticorpos Anti-HIV/sangue , Infecções por HIV/metabolismo , HIV-1/imunologia , HIV-1/metabolismo , Humanos , Testes de Neutralização , Reação em Cadeia da Polimerase , Ruanda , Zâmbia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia
8.
PLoS Pathog ; 12(1): e1005369, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26766578

RESUMO

Broadly neutralizing antibodies (bnAbs) are thought to be a critical component of a protective HIV vaccine. However, designing vaccines immunogens able to elicit bnAbs has proven unsuccessful to date. Understanding the correlates and immunological mechanisms leading to the development of bnAb responses during natural HIV infection is thus critical to the design of a protective vaccine. The IAVI Protocol C program investigates a large longitudinal cohort of primary HIV-1 infection in Eastern and South Africa. Development of neutralization was evaluated in 439 donors using a 6 cross-clade pseudo-virus panel predictive of neutralization breadth on larger panels. About 15% of individuals developed bnAb responses, essentially between year 2 and year 4 of infection. Statistical analyses revealed no influence of gender, age or geographical origin on the development of neutralization breadth. However, cross-clade neutralization strongly correlated with high viral load as well as with low CD4 T cell counts, subtype-C infection and HLA-A*03(-) genotype. A correlation with high overall plasma IgG levels and anti-Env IgG binding titers was also found. The latter appeared not associated with higher affinity, suggesting a greater diversity of the anti-Env responses in broad neutralizers. Broadly neutralizing activity targeting glycan-dependent epitopes, largely the N332-glycan epitope region, was detected in nearly half of the broad neutralizers while CD4bs and gp41-MPER bnAb responses were only detected in very few individuals. Together the findings suggest that both viral and host factors are critical for the development of bnAbs and that the HIV Env N332-glycan supersite may be a favorable target for vaccine design.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Infecções por HIV/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Vacinas contra a AIDS/imunologia , Adulto , África Subsaariana , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Epitopos de Linfócito B/imunologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Proc Natl Acad Sci U S A ; 112(12): E1480-9, 2015 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-25730868

RESUMO

HIV-1 infection is characterized by varying degrees of chronic immune activation and disruption of T-cell homeostasis, which impact the rate of disease progression. A deeper understanding of the factors that influence HIV-1-induced immunopathology and subsequent CD4(+) T-cell decline is critical to strategies aimed at controlling or eliminating the virus. In an analysis of 127 acutely infected Zambians, we demonstrate a dramatic and early impact of viral replicative capacity (vRC) on HIV-1 immunopathogenesis that is independent of viral load (VL). Individuals infected with high-RC viruses exhibit a distinct inflammatory cytokine profile as well as significantly elevated T-cell activation, proliferation, and CD8(+) T-cell exhaustion, during the earliest months of infection. Moreover, the vRC of the transmitted virus is positively correlated with the magnitude of viral burden in naive and central memory CD4(+) T-cell populations, raising the possibility that transmitted viral phenotypes may influence the size of the initial latent viral reservoir. Taken together, these findings support an unprecedented role for the replicative fitness of the founder virus, independent of host protective genes and VL, in influencing multiple facets of HIV-1-related immunopathology, and that a greater focus on this parameter could provide novel approaches to clinical interventions.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Replicação Viral , Contagem de Linfócito CD4 , Linfócitos T CD8-Positivos/imunologia , Estudos de Coortes , Citocinas/sangue , Citocinas/metabolismo , Progressão da Doença , Feminino , Infecções por HIV/sangue , Homeostase , Humanos , Memória Imunológica , Inflamação , Estimativa de Kaplan-Meier , Ativação Linfocitária , Masculino , Dados de Sequência Molecular , Fatores de Tempo , Carga Viral
10.
Ann Hum Genet ; 81(1): 27-34, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28084001

RESUMO

Common single-nucleotide variation in the host accounts for 25% of the variability in the plasma levels of HIV during the clinical latency stage (viral load set point). However, the role of rare variants and copy number variants remains relatively unexplored. Previous work has suggested copy number variation of a cluster of ß-defensin genes affects HIV load in treatment-naïve sub-Saharan Africans and rate of response to antiretroviral treatment. Here we analyse a total of 1827 individuals from two cohorts of HIV-infected individuals from Europe and sub-Saharan Africa to investigate the role of ß-defensin copy number variation on HIV load at set point. We find no evidence for association of copy number with viral load. We also compare distribution of ß-defensin copy number between European cases and controls and find no differences, arguing against a role of ß-defensin copy number in HIV acquisition. Taken together, our data argue against an effect of copy number variation of the ß-defensin region in the spontaneous control of HIV infection.


Assuntos
Síndrome da Imunodeficiência Adquirida/genética , HIV-1/fisiologia , beta-Defensinas/genética , Síndrome da Imunodeficiência Adquirida/virologia , Adulto , Variações do Número de Cópias de DNA , Progressão da Doença , Feminino , Dosagem de Genes , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Carga Viral
11.
J Virol ; 90(22): 10423-10430, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27630231

RESUMO

In individuals with HIV-1 infection, depletion of CD4+ T cells is often accompanied by a malfunction of CD8+ T cells that are persistently activated and/or exhausted. While the dynamics and correlates of CD4 counts have been well documented, the same does not apply to CD8 counts. Here, we examined the CD8 counts in a cohort of 497 Africans with primary HIV-1 infection evaluated in monthly to quarterly follow-up visits for up to 3 years in the absence of antiretroviral therapy. Statistical models revealed that (i) CD8 counts were relatively steady in the 3- to 36-month period of infection and similar between men and women; (ii) neither geography nor heterogeneity in the HIV-1 set-point viral load could account for the roughly 10-fold range of CD8 counts in the cohort (P > 0.25 in all tests); and (iii) factors independently associated with relatively high CD8 counts included demographics (age ≤ 40 years, adjusted P = 0.010) and several human leukocyte antigen class I (HLA-I) alleles, including HLA-A*03:01 (P = 0.013), B*15:10 (P = 0.007), and B*58:02 (P < 0.001). Multiple sensitivity analyses provided supporting evidence for these novel relationships. Overall, these findings suggest that factors associated with the CD8 count have little overlap with those previously reported for other HIV-1-related outcome measures, including viral load, CD4 count, and CD4/CD8 ratio. IMPORTANCE: Longitudinal data from 497 HIV-1 seroconverters allowed us to systematically evaluate the dynamics and correlates of CD8+ T-cell counts during untreated primary HIV-1 infection in eastern and southern Africans. Our findings suggest that individuals with certain HLA-I alleles, including A*03 (exclusively A*03:01), persistently maintain relatively high CD8 counts following HIV-1 infection, a finding which may offer an intriguing explanation for the recently reported, negative association of A*03 with HIV-1-specific, broadly neutralizing antibody responses. In future studies, attention to HLA-I genotyping data may benefit in-depth understanding of both cellular and humoral immunity, as well as the intrinsic balances of these types of immunity, especially in settings where there is emerging evidence of antagonism between the two arms of adaptive immunity.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , Adulto , África , População Negra , Contagem de Linfócito CD4/métodos , Linfócitos T CD4-Positivos/imunologia , Feminino , Genótipo , Soropositividade para HIV/imunologia , Humanos , Masculino , Carga Viral/imunologia
12.
PLoS Pathog ; 11(8): e1005111, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26302050

RESUMO

Antiretroviral therapy, antibody and CD8+ T cell-mediated responses targeting human immunodeficiency virus-1 (HIV-1) exert selection pressure on the virus necessitating escape; however, the ability of CD4+ T cells to exert selective pressure remains unclear. Using a computational approach on HIV gag/pol/nef sequences and HLA-II allelic data, we identified 29 HLA-II associated HIV sequence polymorphisms or adaptations (HLA-AP) in an African cohort of chronically HIV-infected individuals. Epitopes encompassing the predicted adaptation (AE) or its non-adapted (NAE) version were evaluated for immunogenicity. Using a CD8-depleted IFN-γ ELISpot assay, we determined that the magnitude of CD4+ T cell responses to the predicted epitopes in controllers was higher compared to non-controllers (p<0.0001). However, regardless of the group, the magnitude of responses to AE was lower as compared to NAE (p<0.0001). CD4+ T cell responses in patients with acute HIV infection (AHI) demonstrated poor immunogenicity towards AE as compared to NAE encoded by their transmitted founder virus. Longitudinal data in AHI off antiretroviral therapy demonstrated sequence changes that were biologically confirmed to represent CD4+ escape mutations. These data demonstrate an innovative application of HLA-associated polymorphisms to identify biologically relevant CD4+ epitopes and suggests CD4+ T cells are active participants in driving HIV evolution.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Epitopos de Linfócito T/genética , Infecções por HIV/genética , HIV-1/genética , Antígenos de Histocompatibilidade Classe II/genética , Evasão da Resposta Imune/genética , ELISPOT , Epitopos de Linfócito T/imunologia , Evolução Molecular , Citometria de Fluxo , Genótipo , Infecções por HIV/imunologia , HIV-1/imunologia , Humanos , Evasão da Resposta Imune/imunologia , Reação em Cadeia da Polimerase , Polimorfismo Genético
13.
Epidemiology ; 28(2): 224-232, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27893488

RESUMO

BACKGROUND: Understanding associations between pregnancy and HIV disease progression is critical to provide appropriate counseling and care to HIV-positive women. METHODS: From 2006 to 2011, women less than age 40 with incident HIV infection were enrolled in an early HIV infection cohort in Kenya, Rwanda, South Africa, Uganda, and Zambia. Time-dependent Cox models evaluated associations between pregnancy and HIV disease progression. Clinical progression was defined as a single CD4 measurement <200 cells/µl, percent CD4 <14%, or category C event, with censoring at antiretroviral (ART) initiation for reasons other than prevention of mother-to-child transmission (PMTCT). Immunologic progression was defined as two consecutive CD4s ≤350 cells/µl or a single CD4 ≤350 cells/µl followed by non-PMTCT ART initiation. Generalized estimating equations assessed changes in CD4 before and after pregnancy. RESULTS: Among 222 women, 63 experienced clinical progression during 783.5 person-years at risk (8.0/100). Among 205 women, 87 experienced immunologic progression during 680.1 person-years at risk (12.8/100). The association between pregnancy and clinical progression was adjusted hazard ratio [aHR] = 0.7; 95% confidence interval (CI): 0.2, 1.8. The association between pregnancy and immunologic progression was aHR = 1.7; 95% CI: 0.9, 3.3. Models controlled for age; human leukocyte antigen alleles A*03:01, B*45, B*57; CD4 set point; and HIV-1 subtype. CD4 measurements before versus after pregnancies were not different. CONCLUSIONS: In this cohort, pregnancy was not associated with increased clinical or immunologic HIV progression. Similarly, we did not observe meaningful deleterious associations of pregnancy with CD4s. Our findings suggest that HIV-positive women may become pregnant without harmful health effects occurring during the pregnancy. Evaluation of longer-term impact of pregnancy on progression is warranted.


Assuntos
Infecções por HIV/imunologia , Complicações Infecciosas na Gravidez/imunologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Estudos de Coortes , Progressão da Doença , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Quênia , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Modelos de Riscos Proporcionais , Ruanda , África do Sul , Uganda , Zâmbia
14.
Mol Ecol ; 26(7): 1991-2005, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27862555

RESUMO

Emerging infections caused by fungi have become a widely recognized global phenomenon and are causing an increasing burden of disease. Genomic techniques are providing new insights into the structure of fungal populations, revealing hitherto undescribed fine-scale adaptations to environments and hosts that govern their emergence as infections. Cryptococcal meningitis is a neglected tropical disease that is responsible for a large proportion of AIDS-related deaths across Africa; however, the ecological determinants that underlie a patient's risk of infection remain largely unexplored. Here, we use genome sequencing and ecological genomics to decipher the evolutionary ecology of the aetiological agents of cryptococcal meningitis, Cryptococcus neoformans and Cryptococcus gattii, across the central African country of Zambia. We show that the occurrence of these two pathogens is differentially associated with biotic (macroecological) and abiotic (physical) factors across two key African ecoregions, Central Miombo woodlands and Zambezi Mopane woodlands. We show that speciation of Cryptococcus has resulted in adaptation to occupy different ecological niches, with C. neoformans found to occupy Zambezi Mopane woodlands and C. gattii primarily recovered from Central Miombo woodlands. Genome sequencing shows that C. neoformans causes 95% of human infections in this region, of which over three-quarters belonged to the globalized lineage VNI. We show that VNI infections are largely associated with urbanized populations in Zambia. Conversely, the majority of C. neoformans isolates recovered in the environment belong to the genetically diverse African-endemic lineage VNB, and we show hitherto unmapped levels of genomic diversity within this lineage. Our results reveal the complex evolutionary ecology that underpins the reservoirs of infection for this, and likely other, deadly pathogenic fungi.


Assuntos
Adaptação Fisiológica/genética , Cryptococcus gattii/genética , Cryptococcus neoformans/genética , Florestas , Meningite Criptocócica/microbiologia , Código de Barras de DNA Taxonômico , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Genética Populacional , Genoma Fúngico , Genômica , Humanos , Meningite Criptocócica/epidemiologia , Modelos Biológicos , Filogenia , Casca de Planta/microbiologia , Polimorfismo de Nucleotídeo Único , Microbiologia do Solo , Árvores/microbiologia , Zâmbia
15.
Sex Transm Infect ; 93(4): 259-266, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28082662

RESUMO

BACKGROUND: We present temporal trends in self-reported and biological markers of unprotected sex and sex with concurrent partners in discordant couples receiving couples' voluntary HIV counselling and testing (CVCT). METHODS: Heterosexual Zambian HIV-serodiscordant couples were enrolled into longitudinal follow-up in an open cohort (1994-2012). Multivariable Anderson-Gill models explored predictors of self-report and biological indicators of unprotected sex within (including sperm on a vaginal swab, incident pregnancy or incident linked HIV infection) and outside (including self-report, STI and unlinked HIV infection) the union. Measures of secular trends in baseline measures were also examined. RESULTS: At enrolment of 3049 couples, men were 35 years old on average, women were 29 years, and couples had been together for an average of 7 years. M+F- couples reported an average of 16.6 unprotected sex acts in the 3 months prior to enrolment (pre-CVCT), dropping to 5.3 in the >0-3 month interval, and 2.0 in >6 month intervals (p-trend <0.001). Corresponding values for M-F+ couples were 22.4 unprotected sex acts in the 3 months prior enrolment, dropping to 5.2 in the >0-3 month interval, and 3.1 in >6 month intervals (p-trend <0.001). Significant reductions in self-report and biological markers of outside partners were also noted. Predictors of unprotected sex between study partners after CVCT included prevalent pregnancy (adjusted HR, aHR=1.6-1.9); HIV+ men being circumcised (aHR=1.2); and HIV- women reporting sex with outside partners (aHR=1.3), alcohol (aHR=1.2), injectable (aHR=1.4) or oral (aHR=1.4) contraception use. Fertility intentions were also predictive of unprotected sex (aHR=1.2-1.4). Secular trends indicated steady declines in reported outside partners and STIs. CONCLUSION: Reductions in self-reported unprotected sex after CVCT were substantial and sustained. Reinforced risk-reduction counselling in pregnant couples, couples desiring children and couples with HIV- women having outside partners or using alcohol or injectable or oral contraception are indicated.


Assuntos
Preservativos/estatística & dados numéricos , Aconselhamento , Características da Família , Soropositividade para HIV/psicologia , Comportamento de Redução do Risco , Adulto , Comportamento Contraceptivo , Aconselhamento/métodos , Feminino , Seguimentos , Heterossexualidade , Humanos , Estudos Longitudinais , Masculino , Cooperação do Paciente/estatística & dados numéricos , Comportamento Sexual/psicologia , Parceiros Sexuais/psicologia , Zâmbia
16.
BMC Infect Dis ; 17(1): 354, 2017 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-28521833

RESUMO

BACKGROUND: In Zambia, 14.2% of adults have HIV/AIDS. There has been a substantial and significant increase in patients hospitalized for ischaemic stroke with co-existing HIV infection. However, little is known about the mechanism of stroke in these HIV + ve patients let alone studied in our region. The aim of this pilot study was to explore the association of hypercoagulability state in HIV + ve patients with ischaemic stroke. This was achieved by comparing hypercoagulability state markers between HIV + ve ischaemic stroke patients with HIV-ve and HIV + ve patients with and without ischaemic stroke respectively. METHODS: A matched case control study in which a total of 52 HIV + ve patients with ischaemic stroke were prospectively compared with control groups for the presence of protein S, protein C deficiencies and hyperhomocysteinaemia. The control groups comprised an equal number of consecutively matched for age and sex HIV-ve and HIV + ve patients with and without ischaemic stroke respectively. Data was analysed in contingency tables using Paired t- test, Chi square and conditional logistic regression. RESULTS: Ischaemic stroke of undetermined aetiology occurred more frequently in HIV + ve compared to HIV-ve patients (p < 0.001). In addition, protein S deficiency and Hyperhomocysteinaemia were more prominent in HIV + ve than HIV-ve ischaemic stroke patients (P = 0.011). There was no difference in the presence of hyperhomocysteinaemia or protein S deficiency in HIV + ve patients with or without ischaemic stroke. Protein C deficiency was not noted to be significantly different between the cases and the two control arms. CONCLUSION: Protein S deficiency and hyperhomocysteinaemia were associated with HIV infection, but not stroke in our study population. However, this is an area that requires extensive research and one that we cannot afford to ignore as it is an important bridge to all cardiovascular and cerebrovascular diseases.


Assuntos
Infecções por HIV/complicações , Acidente Vascular Cerebral/etiologia , Trombofilia/complicações , Isquemia Encefálica/sangue , Isquemia Encefálica/complicações , Estudos de Casos e Controles , Feminino , Infecções por HIV/sangue , Hospitais de Ensino , Hospitais Universitários , Humanos , Hiper-Homocisteinemia/etiologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Deficiência de Proteína S/etiologia , Trombofilia/virologia , Zâmbia
17.
JAMA ; 318(13): 1233-1240, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28973227

RESUMO

Importance: The effect of an early resuscitation protocol on sepsis outcomes in developing countries remains unknown. Objective: To determine whether an early resuscitation protocol with administration of intravenous fluids, vasopressors, and blood transfusion decreases mortality among Zambian adults with sepsis and hypotension compared with usual care. Design, Setting, and Participants: Randomized clinical trial of 212 adults with sepsis (suspected infection plus ≥2 systemic inflammatory response syndrome criteria) and hypotension (systolic blood pressure ≤90 mm Hg or mean arterial pressure ≤65 mm Hg) presenting to the emergency department at a 1500-bed referral hospital in Zambia between October 22, 2012, and November 11, 2013. Data collection concluded December 9, 2013. Interventions: Patients were randomized 1:1 to either (1) an early resuscitation protocol for sepsis (n = 107) that included intravenous fluid bolus administration with monitoring of jugular venous pressure, respiratory rate, and arterial oxygen saturation and treatment with vasopressors targeting mean arterial pressure (≥65 mm Hg) and blood transfusion (for patients with a hemoglobin level <7 g/dL) or (2) usual care (n = 105) in which treating clinicians determined hemodynamic management. Main Outcomes and Measures: The primary outcome was in-hospital mortality and the secondary outcomes included the volume of intravenous fluid received and receipt of vasopressors. Results: Among 212 patients randomized to receive either the sepsis protocol or usual care, 3 were ineligible and the remaining 209 completed the study and were included in the analysis (mean [SD] age, 36.7 [12.4] years; 117 men [56.0%]; 187 [89.5%] positive for the human immunodeficiency virus). The primary outcome of in-hospital mortality occurred in 51 of 106 patients (48.1%) in the sepsis protocol group compared with 34 of 103 patients (33.0%) in the usual care group (between-group difference, 15.1% [95% CI, 2.0%-28.3%]; relative risk, 1.46 [95% CI, 1.04-2.05]; P = .03). In the 6 hours after presentation to the emergency department, patients in the sepsis protocol group received a median of 3.5 L (interquartile range, 2.7-4.0 L) of intravenous fluid compared with 2.0 L (interquartile range, 1.0-2.5 L) in the usual care group (mean difference, 1.2 L [95% CI, 1.0-1.5 L]; P < .001). Fifteen patients (14.2%) in the sepsis protocol group and 2 patients (1.9%) in the usual care group received vasopressors (between-group difference, 12.3% [95% CI, 5.1%-19.4%]; P < .001). Conclusions and Relevance: Among adults with sepsis and hypotension, most of whom were positive for HIV, in a resource-limited setting, a protocol for early resuscitation with administration of intravenous fluids and vasopressors increased in-hospital mortality compared with usual care. Further studies are needed to understand the effects of administration of intravenous fluid boluses and vasopressors in patients with sepsis across different low- and middle-income clinical settings and patient populations. Trial Registration: clinicaltrials.gov Identifier: NCT01663701.


Assuntos
Hidratação , Mortalidade Hospitalar , Hipotensão/terapia , Ressuscitação/métodos , Sepse/terapia , Vasoconstritores/uso terapêutico , Adulto , Transfusão de Sangue , Protocolos Clínicos , Soluções Cristaloides , Feminino , Soropositividade para HIV/complicações , Humanos , Hipotensão/etiologia , Infusões Intravenosas , Soluções Isotônicas/uso terapêutico , Estimativa de Kaplan-Meier , Masculino , Sepse/complicações , Sepse/mortalidade , Tempo para o Tratamento , Zâmbia
18.
Hum Genet ; 133(9): 1187-97, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24969460

RESUMO

Research in the past two decades has generated unequivocal evidence that host genetic variations substantially account for the heterogeneous outcomes following human immunodeficiency virus type 1 (HIV-1) infection. In particular, genes encoding human leukocyte antigens (HLA) have various alleles, haplotypes, or specific motifs that can dictate the set-point (a relatively steady state) of plasma viral load (VL), although rapid viral evolution driven by innate and acquired immune responses can obscure the long-term relationships between HLA genotypes and HIV-1-related outcomes. In our analyses of VL data from 521 recent HIV-1 seroconverters enrolled from eastern and southern Africa, HLA-A*03:01 was strongly and persistently associated with low VL in women (frequency = 11.3 %, P < 0.0001) but not in men (frequency = 7.7 %, P = 0.66). This novel sex by HLA interaction (P = 0.003, q = 0.090) did not extend to other frequent HLA class I alleles (n = 34), although HLA-C*18:01 also showed a weak association with low VL in women only (frequency = 9.3 %, P = 0.042, q > 0.50). In a reduced multivariable model, age, sex, geography (clinical sites), previously identified HLA factors (HLA-B*18, B*45, B*53, and B*57), and the interaction term for female sex and HLA-A*03:01 collectively explained 17.0 % of the overall variance in geometric mean VL over a 3-year follow-up period (P < 0.0001). Multiple sensitivity analyses of longitudinal and cross-sectional VL data yielded consistent results. These findings can serve as a proof of principle that the gap of "missing heritability" in quantitative genetics can be partially bridged by a systematic evaluation of sex-specific associations.


Assuntos
Variação Genética , Infecções por HIV/genética , HIV-1/imunologia , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígenos HLA-C/genética , Adulto , África Oriental , África Ocidental , Alelos , Estudos Transversais , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , Soropositividade para HIV , Antígenos HLA-A/imunologia , Antígenos HLA-B/imunologia , Antígenos HLA-C/imunologia , Haplótipos , Humanos , Desequilíbrio de Ligação , Estudos Longitudinais , Masculino , Análise Multivariada , Característica Quantitativa Herdável , Fatores Sexuais , Carga Viral , Adulto Jovem
19.
Crit Care Med ; 42(11): 2315-24, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25072757

RESUMO

OBJECTIVE: To assess the efficacy of a simple, goal-directed sepsis treatment protocol for reducing mortality in patients with severe sepsis in Zambia. DESIGN: Single-center nonblinded randomized controlled trial. SETTING: Emergency department, ICU, and medical wards of the national referral hospital in Lusaka, Zambia. PATIENTS: One hundred twelve patients enrolled within 24 hours of admission with severe sepsis, defined as systemic inflammatory response syndrome with suspected infection and organ dysfunction INTERVENTIONS: : Simplified Severe Sepsis Protocol consisting of up to 4 L of IV fluids within 6 hours, guided by jugular venous pressure assessment, and dopamine and/or blood transfusion in selected patients. Control group was managed as usual care. Blood cultures were collected and early antibiotics administered for both arms. MEASUREMENTS AND MAIN RESULTS: Primary outcome was in-hospital all-cause mortality. One hundred nine patients were included in the final analysis and 88 patients (80.7%) were HIV positive. Pulmonary infections were the most common source of sepsis. In-hospital mortality rate was 64.2% in the intervention group and 60.7% in the control group (relative risk, 1.05; 95% CI, 0.79-1.41). Mycobacterium tuberculosis complex was isolated from 31 of 82 HIV-positive patients (37.8%) with available mycobacterial blood culture results. Patients in Simplified Severe Sepsis Protocol received significantly more IV fluids in the first 6 hours (2.7 L vs 1.7 L, p = 0.002). The study was stopped early because of high mortality rate among patients with hypoxemic respiratory failure in the intervention arm (8/8, 100%) compared with the control arm (7/10, 70%; relative risk, 1.43; 95% CI, 0.95-2.14). CONCLUSION: Factors other than tissue hypoperfusion probably account for much of the end-organ dysfunction in African patients with severe sepsis. Studies of fluid-based interventions should utilize inclusion criteria to accurately capture patients with hypovolemia and tissue hypoperfusion who are most likely to benefit from fluids. Exclusion of patients with severe respiratory distress should be considered when ventilatory support is not readily available.


Assuntos
Cuidados Críticos/métodos , Mortalidade Hospitalar , Sepse/mortalidade , Sepse/terapia , Adulto , Antibacterianos/uso terapêutico , Transfusão de Sangue/métodos , Terapia Combinada , Países em Desenvolvimento , Dopamina/uso terapêutico , Serviço Hospitalar de Emergência , Feminino , Hidratação/métodos , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Medição de Risco , Sepse/diagnóstico , Choque Séptico/diagnóstico , Choque Séptico/mortalidade , Choque Séptico/terapia , Análise de Sobrevida , Resultado do Tratamento , Zâmbia
20.
J Virol ; 87(2): 708-15, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23115285

RESUMO

In HIV-1 infection, the early set-point viral load strongly predicts both viral transmission and disease progression. The factors responsible for the wide spectrum of set-point viral loads are complex and likely reflect an interplay between the transmitted virus and genetically defined factors in both the transmitting source partner and the seroconverter. Indeed, analysis of 195 transmission pairs from Lusaka, Zambia, revealed that the viral loads in transmitting source partners contributed only ∼2% of the variance in early set-point viral loads of seroconverters (P = 0.046 by univariable analysis). In multivariable models, early set-point viral loads in seroconverting partners were a complex function of (i) the viral load in the source partner, (ii) the gender of the seroconverter, (iii) specific HLA class I alleles in the newly infected partner, and (iv) sharing of HLA-I alleles between partners in a transmission pair. Each of these factors significantly and independently contributed to the set-point viral load in the newly infected partner, accounting for up to 37% of the variance observed and suggesting that many factors operate in concert to define the early virological phenotype in HIV-1 infection.


Assuntos
Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , HIV-1/patogenicidade , Carga Viral , Adulto , Feminino , Infecções por HIV/genética , Infecções por HIV/transmissão , Antígenos de Histocompatibilidade Classe I/genética , Interações Hospedeiro-Patógeno , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Zâmbia
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