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1.
Commun Biol ; 7(1): 41, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182727

RESUMO

Burkitt lymphoma (BL) is responsible for many childhood cancers in sub-Saharan Africa, where it is linked to recurrent or chronic infection by Epstein-Barr virus or Plasmodium falciparum. However, whether human leukocyte antigen (HLA) polymorphisms, which regulate immune response, are associated with BL has not been well investigated, which limits our understanding of BL etiology. Here we investigate this association among 4,645 children aged 0-15 years, 800 with BL, enrolled in Uganda, Tanzania, Kenya, and Malawi. HLA alleles are imputed with accuracy >90% for HLA class I and 85-89% for class II alleles. BL risk is elevated with HLA-DQA1*04:01 (adjusted odds ratio [OR] = 1.61, 95% confidence interval [CI] = 1.32-1.97, P = 3.71 × 10-6), with rs2040406(G) in HLA-DQA1 region (OR = 1.43, 95% CI = 1.26-1.63, P = 4.62 × 10-8), and with amino acid Gln at position 53 versus other variants in HLA-DQA1 (OR = 1.36, P = 2.06 × 10-6). The associations with HLA-DQA1*04:01 (OR = 1.29, P = 0.03) and rs2040406(G) (OR = 1.68, P = 0.019) persist in mutually adjusted models. The higher risk rs2040406(G) variant for BL is associated with decreased HLA-DQB1 expression in eQTLs in EBV transformed lymphocytes. Our results support the role of HLA variation in the etiology of BL and suggest that a promising area of research might be understanding the link between HLA variation and EBV control.


Assuntos
Linfoma de Burkitt , Infecções por Vírus Epstein-Barr , Criança , Humanos , Linfoma de Burkitt/genética , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Herpesvirus Humano 4/genética , Cadeias alfa de HLA-DQ/genética
2.
Am J Hematol ; 99(1): 113-123, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38009642

RESUMO

Burkitt lymphoma (BL) is an aggressive B-cell lymphoma that significantly contributes to childhood cancer burden in sub-Saharan Africa. Plasmodium falciparum, which causes malaria, is geographically associated with BL, but the evidence remains insufficient for causal inference. Inference could be strengthened by demonstrating that mendelian genes known to protect against malaria-such as the sickle cell trait variant, HBB-rs334(T)-also protect against BL. We investigated this hypothesis among 800 BL cases and 3845 controls in four East African countries using genome-scan data to detect polymorphisms in 22 genes known to affect malaria risk. We fit generalized linear mixed models to estimate odds ratios (OR) and 95% confidence intervals (95% CI), controlling for age, sex, country, and ancestry. The ORs of the loci with BL and P. falciparum infection among controls were correlated (Spearman's ρ = 0.37, p = .039). HBB-rs334(T) was associated with lower P. falciparum infection risk among controls (OR = 0.752, 95% CI 0.628-0.9; p = .00189) and BL risk (OR = 0.687, 95% CI 0.533-0.885; p = .0037). ABO-rs8176703(T) was associated with decreased risk of BL (OR = 0.591, 95% CI 0.379-0.992; p = .00271), but not of P. falciparum infection. Our results increase support for the etiological correlation between P. falciparum and BL risk.


Assuntos
Linfoma de Burkitt , Malária Falciparum , Malária , Traço Falciforme , Humanos , África Oriental , Alelos , Linfoma de Burkitt/epidemiologia , Linfoma de Burkitt/genética , Malária Falciparum/epidemiologia , Malária Falciparum/genética , Malária Falciparum/complicações , Traço Falciforme/epidemiologia , Traço Falciforme/genética , Traço Falciforme/complicações , Nectinas/metabolismo
3.
Nat Commun ; 14(1): 8081, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057307

RESUMO

In high-income countries, mosaic chromosomal alterations in peripheral blood leukocytes are associated with an elevated risk of adverse health outcomes, including hematologic malignancies. We investigate mosaic chromosomal alterations in sub-Saharan Africa among 931 children with Burkitt lymphoma, an aggressive lymphoma commonly characterized by immunoglobulin-MYC chromosomal rearrangements, 3822 Burkitt lymphoma-free children, and 674 cancer-free men from Ghana. We find autosomal and X chromosome mosaic chromosomal alterations in 3.4% and 1.7% of Burkitt lymphoma-free children, and 8.4% and 3.7% of children with Burkitt lymphoma (P-values = 5.7×10-11 and 3.74×10-2, respectively). Autosomal mosaic chromosomal alterations are detected in 14.0% of Ghanaian men and increase with age. Mosaic chromosomal alterations in Burkitt lymphoma cases include gains on chromosomes 1q and 8, the latter spanning MYC, while mosaic chromosomal alterations in Burkitt lymphoma-free children include copy-neutral loss of heterozygosity on chromosomes 10, 14, and 16. Our results highlight mosaic chromosomal alterations in sub-Saharan African populations as a promising area of research.


Assuntos
Linfoma de Burkitt , Masculino , Criança , Humanos , Linfoma de Burkitt/genética , Linfoma de Burkitt/patologia , Gana , Aberrações Cromossômicas , Leucócitos/patologia , Imunoglobulinas/genética , Translocação Genética
4.
BMC Pulm Med ; 23(1): 497, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38071287

RESUMO

BACKGROUND: Despite global tuberculosis (TB) interventions, the disease remains one of the major public health concerns. Kenya is ranked 15th among 22 high burden TB countries globally. METHODS: A cross-sectional study was conducted in Western Kenya, which comprises 10 counties. A multistage sampling method was used where a single sub-county was randomly selected followed by sampling two high volume health facility from each sub-county. Identification of spoligotype profiles and their family distribution and lineage level were achieved by comparison with SITVIT database. RESULTS: Lineage distribution pattern revealed that the most predominant lineage was CAS 220 (39.8%) followed by Beijing 128 (23.1%). The other lineages identified were T, LAM, H, X, S and MANU which were quantified as 87 (15.7%), 67 (12.1%), 16 (2.8%), 10 (1.8%), 8 (1.4%) and 5 (0.9%) respectively. CAS and Beijing strains were the most predominant lineage in both HIV negative and positive TB patients. The Beijing lineage was also the most predominant in resistant M. tuberculosis strains as compared to wild type. A total of 12 (2.0%) were orphaned M. tuberculosis strains which were spread across all the 10 counties of the study site. In multivariate logistic regression adjusting for potential cofounders three potential risk factors were significant. HIV status (OR = 1.52, CI = 0.29-3.68 and P value of 0.001), Alcohol use (OR = 0.59, CI = 0.43-3.12 and P-value =0.001) and cross border travel (OR = 0.61, CI = 0.49-3.87 and P value = 0.026). Most M. tuberculosis clinical isolates showed genetic clustering with multivariate logistic regression indicating three potential risk factors to clustering. HIV status (OR = 1.52, CI = 0.29-3.68 and P value of 0.001), Alcohol use (OR = 0.59, CI = 0.43-3.12 and P-value =0.001) and cross border travel (OR = 0.61, CI = 0.49-3.87 and P value = 0.026). CONCLUSION: There exist diverse strains of M. tuberculosis across the 10 counties of Western Kenya. Predominant distribution of clustered genotype points to the fact that most TB cases in this region are as a result of resent transmission other than activation of latent TB.


Assuntos
Soropositividade para HIV , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Mycobacterium tuberculosis/genética , Estudos Transversais , Quênia/epidemiologia , Epidemiologia Molecular , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Genótipo
5.
J Acquir Immune Defic Syndr ; 94(2): 95-106, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37276188

RESUMO

OBJECTIVES: Adolescent girls and young women younger than 25 years (AGYW) account for disproportionate HIV infections in sub-Saharan Africa. Impacts of war in Northern Uganda continue to affect HIV-related health and wellbeing of young people postconflict. Prevalence and incidence of HIV infection were estimated, and factors associated with HIV prevalence among sexually active AGYW in Northern Uganda were investigated. METHODS: Cango Lyec is a cohort involving conflict-affected populations in Northern Uganda. Nine randomly selected communities in Gulu, Nwoya, and Amuru districts were mapped. House-to-house census was conducted. Consenting participants aged 13-49 years were enrolled over 3 study rounds (2011-2015), of whom 533 were AGYW and had ever had sex. Data were collected on trauma, depression, and sociodemographic-behavioral characteristics. Venous blood was taken for HIV and syphilis serology. Multivariable logistic regression determined baseline factors associated with HIV prevalence. RESULTS: HIV prevalence among AGYW was 9.7% (95% CI: 7.3 to 12.6). AGYW living in Gulu (adjusted risk ratio, aRR: 2.48; 95% CI: 1.12 to 5.51) or Nwoya (aRR: 2.65; 95% CI: 1.03 to 6.83) were more likely than in Amuru to be living with HIV. Having self-reported genital ulcers (aRR: 1.93; 95% CI: 0.97 to 3.85) or active syphilis (aRR: 3.79; 95% CI: 2.35 to 6.12) was associated with increased risk of HIV infection. The likelihood of HIV was higher for those who experienced sexual violence in the context of war (aRR: 2.37; 95% CI: 1.21 to 4.62) and/or probable depression (aRR: 1.95; 95% CI: 1.08 to 3.54). HIV incidence was 8.9 per 1000 person-years. CONCLUSION: Ongoing legacies of war, especially gender violence and trauma, contribute to HIV vulnerability among sexually active AGYW. Wholistic approaches integrating HIV prevention with culturally safe initiatives promoting sexual and mental health in Northern Uganda are essential.


Assuntos
Infecções por HIV , Sífilis , Adolescente , Feminino , Humanos , Infecções por HIV/prevenção & controle , Prevalência , Comportamento Sexual , Uganda/epidemiologia , Adulto Jovem
6.
J Interferon Cytokine Res ; 43(9): 394-402, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37366802

RESUMO

Interferon lambda 4 (IFN-λ4) is a novel type-III interferon that can be expressed only by carriers of the genetic variant rs368234815-dG within the first exon of the IFNL4 gene. Genetic inability to produce IFN-λ4 (in carriers of the rs368234815-TT/TT genotype) has been associated with improved clearance of hepatitis C virus (HCV) infection. The IFN-λ4-expressing rs368234815-dG allele (IFNL4-dG) is most common (up to 78%) in West sub-Saharan Africa (SSA), compared to 35% of Europeans and 5% of individuals from East Asia. The negative selection of IFNL4-dG outside Africa suggests that its retention in African populations could provide survival benefits, most likely in children. To explore this hypothesis, we conducted a comprehensive association analysis between IFNL4 genotypes and the risk of childhood Burkitt lymphoma (BL), a lethal infection-associated cancer most common in SSA. We used genetic, epidemiologic, and clinical data for 4,038 children from the Epidemiology of Burkitt Lymphoma in East African Children and Minors (EMBLEM) and the Malawi Infections and Childhood Cancer case-control studies. Generalized linear mixed models fit with the logit link controlling for age, sex, country, P. falciparum infection status, population stratification, and relatedness found no significant association between BL risk and 3 coding genetic variants within IFNL4 (rs368234815, rs117648444, and rs142981501) and their combinations. Because BL occurs in children 6-9 years of age who survived early childhood infections, our results suggest that additional studies should explore the associations of IFNL4-dG allele in younger children. This comprehensive study represents an important baseline in defining the health effects of IFN-λ4 in African populations.


Assuntos
Linfoma de Burkitt , Hepatite C , Pré-Escolar , Criança , Humanos , Linfoma de Burkitt/genética , Genótipo , Hepatite C/complicações , Hepatite C/genética , Hepacivirus/genética , África Oriental , Interleucinas/genética , Interleucinas/farmacologia , Polimorfismo de Nucleotídeo Único
7.
J Surg Res ; 286: 23-34, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36738566

RESUMO

INTRODUCTION: Children's surgical access in low and low-middle income countries is severely limited. Investigations detailing met and unmet surgical access are necessary to inform appropriate resource allocation. MATERIALS AND METHODS: Surgical volume, outcomes, and distribution of pediatric general surgical procedures were analyzed using prospective pediatric surgical databases from four separate regional hospitals in Uganda. The current averted burden of surgical disease through pediatric surgical delivery in Uganda and the unmet surgical need based on estimates from high-income country data was calculated. RESULTS: A total of 8514 patients were treated at the four hospitals over a 6-year period corresponding to 1350 pediatric surgical cases per year in Uganda or six surgical cases per 100,000 children per year. The majority of complex congenital anomalies and surgical oncology cases were performed at Mulago and Mbarara Hospitals, which have dedicated pediatric surgical teams (P < 0.0001). The averted burden of pediatric surgical disease was 27,000 disability adjusted life years per year, which resulted in an economic benefit of approximately 23 million USD per year. However, the average case volume performed at the four regional hospitals currently represents 1% of the total projected pediatric surgical need. CONCLUSIONS: This investigation is one of the first to demonstrate the distribution of pediatric surgical procedures at a country level through the use of a prospective locally created database. Significant disease burden was averted by local pediatric and adult surgical teams, demonstrating the economic benefit of pediatric surgical care delivery. These findings support several ongoing strategies to increase pediatric surgical access in Uganda.


Assuntos
Especialidades Cirúrgicas , Adulto , Humanos , Criança , Uganda/epidemiologia , Hospitais , Análise Custo-Benefício , Necessidades e Demandas de Serviços de Saúde
8.
Proc Natl Acad Sci U S A ; 120(2): e2211055120, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36595676

RESUMO

Endemic Burkitt lymphoma (eBL) is a pediatric cancer coendemic with malaria in sub-Saharan Africa, suggesting an etiological link between them. However, previous cross-sectional studies of limited geographic areas have not found a convincing association. We used spatially detailed data from the Epidemiology of Burkitt Lymphoma in East African Children and Minors (EMBLEM) study to assess this relationship. EMBLEM is a case-control study of eBL from 2010 through 2016 in six regions of Kenya, Uganda, and Tanzania. To measure the intensity of exposure to the malaria parasite, Plasmodium falciparum, among children in these regions, we used high-resolution spatial data from the Malaria Atlas Project to estimate the annual number of P. falciparum infections from 2000 through 2016 for each of 49 districts within the study region. Cumulative P. falciparum exposure, calculated as the sum of annual infections by birth cohort, varied widely, with a median of 47 estimated infections per child by age 10, ranging from 4 to 315 infections. eBL incidence increased 39% for each 100 additional lifetime P. falciparum infections (95% CI: 6.10 to 81.04%) with the risk peaking among children aged 5 to 11 and declining thereafter. Alternative models using estimated annual P. falciparum infections 0 to 10 y before eBL onset were inconclusive, suggesting that eBL risk is a function of cumulative rather than recent cross-sectional exposure. Our findings provide population-level evidence that eBL is a phenotype related to heavy lifetime exposure to P. falciparum malaria and support emphasizing the link between malaria and eBL.


Assuntos
Linfoma de Burkitt , Malária Falciparum , Malária , Humanos , Linfoma de Burkitt/epidemiologia , Linfoma de Burkitt/genética , Plasmodium falciparum , Estudos de Casos e Controles , Uganda/epidemiologia , Quênia/epidemiologia , Tanzânia/epidemiologia , Estudos Transversais , Malária Falciparum/complicações , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Malária/epidemiologia
9.
Clin Infect Dis ; 76(9): 1585-1593, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-36519341

RESUMO

BACKGROUND: Artemisinin-resistant Plasmodium falciparum is spreading in Southeast Asia and Africa. In vivo susceptibility to artemisinin is studied by looking at the rate of decline of peripheral parasitemia (parasite clearance half-life). However, parasites that are adhered/sequestered to the endothelium and undetectable in the peripheral blood are not considered in the estimation of parasite clearance. Here, we evaluated the influence of sequestration on in vivo artemisinin efficacy in Uganda, where artemisinin resistance is spreading. METHODS: We analyzed 133 patients with P. falciparum malaria included in an in vivo study on artemisinin efficacy in northern Uganda in 2018 and 2019. The parasite clearance half-life was estimated from peripheral parasitemia after artemisinin monotherapy. P. falciparum histidine-rich protein 2 (PfHRP2) was measured in pretreatment plasma. The number of sequestered parasites was estimated from PfHRP2 concentration and peripheral parasitemia. RESULTS: The estimated number of sequestered parasites per plasma volume ranged from 0 to 2 564 000/µL. Inflammation, thrombocytopenia, and dyslipidemia were significantly associated with sequestration independent of peripheral parasitemia. The median parasite clearance half-lives were 1.65 hours in patients infected with Pfkelch13 wild-type parasites (n = 104) and 3.95 hours in those with A675V artemisinin-resistant mutant (n = 18). In the multivariable model for the wild-type population, 1 000 000/µL of sequestered parasites were estimated to delay parasite clearance by 16.8% (95% confidence interval, 5.1%-28.5%), although it was not clear in the A675V population. CONCLUSIONS: In patients with P. falciparum malaria without artemisinin-resistant mutations, intensive sequestration delays parasite clearance after treatment, which may contribute to reduced artemisinin efficacy.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Parasitos , Animais , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Parasitemia/tratamento farmacológico , Resistência a Medicamentos , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Plasmodium falciparum/genética , Uganda/epidemiologia , Proteínas de Protozoários/genética
10.
Blood ; 141(8): 904-916, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36201743

RESUMO

Burkitt lymphoma (BL) accounts for most pediatric non-Hodgkin lymphomas, being less common but significantly more lethal when diagnosed in adults. Much of the knowledge of the genetics of BL thus far has originated from the study of pediatric BL (pBL), leaving its relationship to adult BL (aBL) and other adult lymphomas not fully explored. We sought to more thoroughly identify the somatic changes that underlie lymphomagenesis in aBL and any molecular features that associate with clinical disparities within and between pBL and aBL. Through comprehensive whole-genome sequencing of 230 BL and 295 diffuse large B-cell lymphoma (DLBCL) tumors, we identified additional significantly mutated genes, including more genetic features that associate with tumor Epstein-Barr virus status, and unraveled new distinct subgroupings within BL and DLBCL with 3 predominantly comprising BLs: DGG-BL (DDX3X, GNA13, and GNAI2), IC-BL (ID3 and CCND3), and Q53-BL (quiet TP53). Each BL subgroup is characterized by combinations of common driver and noncoding mutations caused by aberrant somatic hypermutation. The largest subgroups of BL cases, IC-BL and DGG-BL, are further characterized by distinct biological and gene expression differences. IC-BL and DGG-BL and their prototypical genetic features (ID3 and TP53) had significant associations with patient outcomes that were different among aBL and pBL cohorts. These findings highlight shared pathogenesis between aBL and pBL, and establish genetic subtypes within BL that serve to delineate tumors with distinct molecular features, providing a new framework for epidemiologic, diagnostic, and therapeutic strategies.


Assuntos
Linfoma de Burkitt , Infecções por Vírus Epstein-Barr , Linfoma Difuso de Grandes Células B , Criança , Humanos , Adulto , Linfoma de Burkitt/patologia , Herpesvirus Humano 4 , Linfoma Difuso de Grandes Células B/patologia , Mutação
11.
Nat Rev Dis Primers ; 8(1): 78, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36522349

RESUMO

Burkitt lymphoma (BL) is an aggressive form of B cell lymphoma that can affect children and adults. The study of BL led to the identification of the first recurrent chromosomal aberration in lymphoma, t(8;14)(q24;q32), and subsequent discovery of the central role of MYC and Epstein-Barr virus (EBV) in tumorigenesis. Most patients with BL are cured with chemotherapy but those with relapsed or refractory disease usually die of lymphoma. Historically, endemic BL, non-endemic sporadic BL and the immunodeficiency-associated BL have been recognized, but differentiation of these epidemiological variants is confounded by the frequency of EBV positivity. Subtyping into EBV+ and EBV- BL might better describe the biological heterogeneity of the disease. Phenotypically resembling germinal centre B cells, all types of BL are characterized by dysregulation of MYC due to enhancer activation via juxtaposition with one of the three immunoglobulin loci. Additional molecular changes commonly affect B cell receptor and sphingosine-1-phosphate signalling, proliferation, survival and SWI-SNF chromatin remodelling. BL is diagnosed on the basis of morphology and high expression of MYC. BL can be effectively treated in children and adolescents with short durations of high dose-intensity multiagent chemotherapy regimens. Adults are more susceptible to toxic effects but are effectively treated with chemotherapy, including modified versions of paediatric regimens. The outcomes in patients with BL are good in high-income countries with low mortality and few late effects, but in low-income and middle-income countries, BL is diagnosed late and is usually treated with less-effective regimens affecting the overall good outcomes in patients with this lymphoma.


Assuntos
Linfoma de Burkitt , Infecções por Vírus Epstein-Barr , Linfoma , Adolescente , Adulto , Humanos , Criança , Linfoma de Burkitt/epidemiologia , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Herpesvirus Humano 4 , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/epidemiologia , Linfócitos B
12.
J Migr Health ; 6: 100125, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35832466

RESUMO

Background: From 1986 to 2006, Northern Uganda experienced an atrocious civil war between the Lord's Resistance Army (LRA) and the Ugandan government. Acholi people living in the region continue to be impacted by trauma sequelae of the war and a wide range of daily stressors including poverty, hunger, and high rates of HIV infection. To date, there is a dearth of gender-differentiated mental health research in this post-conflict setting. The current study aimed to estimate the prevalence of probable post-traumatic stress disorder (PTSD) and depression in three districts most affected by the Northern Ugandan conflict and examine socio-structural, war-related, and sexual vulnerability factors associated with mental health. Methods: Cango Lyec (Healing the Elephant) is an open cohort study involving participants from eight randomly selected communities in Amuru, Gulu, and Nwoya districts of Northern Uganda. Between November 2011 and July 2012, the baseline cohort (N = 2,458) completed the Harvard Trauma Questionnaire (HTQ) and Hopkins Symptom Checklist-25 (HSCL-25) for screening PTSD and depression, in addition to a detailed questionnaire assessing socio-demographic-behavioral characteristics. Baseline categorical variables were compared between males and females using Fisher's exact test. Multivariate logistic regression was used to model correlates of probable PTSD and depression. All analyses were stratified by gender. Results: The overall prevalence of probable PTSD and depression was 11.7% and 15.2% respectively. Among former abductees, the prevalence was 23.2% for probable PTSD and 26.6% for probable depression. Women were significantly more likely to experience mental distress than men. Factors associated with mental distress included wartime trauma (adjusted odds ratios ranging from 2.80 to 7.19), experiences of abduction (adjusted odds ratios ranging from 1.97 to 3.03), and lack of housing stability and safety (adjusted odds ratios ranging from 1.95 to 4.59). Additional risk factors for women included HIV infection (AOR=1.90; 95% CI: 1.29-2.80), sexual abuse in the context of war (AOR=1.58; 95% CI: 1.02-2.45), and intimate partner violence (AOR=2.45; 95% CI: 1.07-5.63). Conclusion: Cango Lyec participants displayed lower than previously reported yet significant levels of probable PTSD and depression. Based on findings from this study, providing trauma-informed care, ensuring food and housing security, eliminating gender-based violence, and reintegrating former abductees remain important tasks to facilitate post-conflict rehabilitation in Northern Uganda.

13.
BMC Cancer ; 22(1): 484, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35501771

RESUMO

BACKGROUND: The capacity for invasive tissue biopsies followed by histopathology diagnosis in sub-Saharan Africa is severely limited. Consequently, many cancer patients are diagnosed late and outcomes are poor. Here, we propose to evaluate circulating tumour (ct) DNA analysis ("liquid biopsy"), a less invasive and faster approach to diagnose endemic EBV-driven lymphomas (EBVL) in East Africa. METHODS: We will evaluate the clinical utility of an already validated ctDNA test prospectively in a head-to-head comparison against histopathology. The primary endpoint is the time from presentation to the specialist centre to a final diagnosis of EBV- Lymphoma. Secondary endpoints include the sensitivity and specificity of liquid biopsy and health economic benefits over histopathology. One hundred forty-six patients will be recruited over 18 months. Patients will be eligible if they are 3-30 years of age and have provided written consent or assent as per IRB guidelines. Tissue and venous blood samples will be processed as per established protocols. Clinical data will be captured securely and in real-time into a REDCap database. The time from presentation to diagnosis will be documented. The sensitivity and specificity of the methods can be estimated within 5% error margin with 95% confidence level using 73 cases and 73 controls. Health-economic assessment will include micro-costing of ctDNA test and histopathology. All results will be reviewed in a multidisciplinary tumour board. DISCUSSION: The study evaluates the clinical utility of ctDNA in improving the speed of diagnostic pathways for EBVL in sub-Saharan Africa. Our results would provide proof-of-principle that ctDNA can be used as a diagnostic tool in areas without access to regular pathology, that transfer of the tool is feasible, and that it leads to an earlier and faster diagnosis. The potential clinical and economic impact of this proposal is thus significant. If successful, this study will provide appropriate, and cost-effective diagnostic tools that will promote earlier diagnosis of EBVL and potentially other cancers in countries with restricted healthcare resources. TRIAL REGISTRATION: Pan African Clinical Trials Registry:  PACTR202204822312651 , registered on 14th-April-2022.


Assuntos
DNA Tumoral Circulante , Linfoma não Hodgkin , Neoplasias , África Oriental , Biomarcadores Tumorais/genética , Criança , Herpesvirus Humano 4/genética , Humanos , Biópsia Líquida/métodos , Neoplasias/diagnóstico , Adulto Jovem
14.
Front Oncol ; 12: 812224, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35340265

RESUMO

Epstein-Barr virus (EBV) is associated with endemic Burkitt lymphoma (eBL), but the contribution of EBV variants is ill-defined. Studies of EBV whole genome sequences (WGS) have identified phylogroups that appear to be distinct for Asian versus non-Asian EBV, but samples from BL or Africa, where EBV was first discovered, are under-represented. We conducted a phylogenetic analysis of EBV WGS and LMP-1 sequences obtained primarily from BL patients in Africa and representative non-African EBV from other conditions or regions using data from GenBank, Sequence Read Archive, or Genomic Data Commons for the Burkitt Lymphoma Genome Sequencing Project (BLGSP) to generate data to support the use of a simpler biomarker of geographic or phenotypic associations. We also investigated LMP-1 patterns in 414 eBL cases and 414 geographically matched controls in the Epidemiology of Burkitt Lymphoma in East African children and minors (EMBLEM) study using LMP-1 PCR and Sanger sequencing. Phylogenetic analysis revealed distinct genetic patterns of African versus Asian EBV sequences. We identified 281 single nucleotide variations (SNVs) in LMP-1 promoter and coding region, which formed 12 unique patterns (A to L). Nine patterns (A, AB, C, D, F, I, J, K and L) predominated in African EBV, of which four were found in 92% of BL samples (A, AB, D, and H). Predominant patterns were B and G in Asia and H in Europe. EBV positivity in peripheral blood was detected in 95.6% of EMBLEM eBL cases versus 79.2% of the healthy controls (odds ratio [OR] =3.83; 95% confidence interval 2.06-7.14). LMP-1 was successfully sequenced in 66.7% of the EBV DNA positive cases but in 29.6% of the controls (ORs ranging 5-11 for different patterns). Four LMP-1 patterns (A, AB, D, and K) were detected in 63.1% of the cases versus 27.1% controls (ORs ranges: 5.58-11.4). Dual strain EBV infections were identified in WGS and PCR-Sanger data. In conclusion, EBV from Africa is phylogenetically separate from EBV in Asia. Genetic diversity in LMP-1 formed 12 patterns, which showed promising geographic and phenotypic associations. Presence of multiple strain infection should be considered in efforts to refine or improve EBV markers of ancestry or phenotype. Lay Summary: Epstein-Barr virus (EBV) infection, a ubiquitous infection, contributes to the etiology of both Burkitt Lymphoma (BL) and nasopharyngeal carcinoma, yet their global distributions vary geographically with no overlap. Genomic variation in EBV is suspected to play a role in the geographical patterns of these EBV-associated cancers, but relatively few EBV samples from BL have been comprehensively studied. We sought to compare phylogenetic patterns of EBV genomes obtained from BL samples in Africa and from tumor and non-tumor samples from elsewhere. We concluded that EBV obtained from BL in Africa is genetically separate from EBV in Asia. Through comprehensive analysis of nucleotide variations in EBV's LMP-1 gene, we describe 12 LMP-1 patterns, two of which (B and G) were found mostly in Asia. Four LMP-1 patterns (A, AB, D, and F) accounted for 92% of EBVs sequenced from BL in Africa. Our results identified extensive diversity of EBV, but BL in Africa was associated with a limited number of variants identified, which were different from those identified in Asia. Further research is needed to optimize the use of PCR and sequencing to study LMP-1 diversity for classification of EBV variants and for use in epidemiologic studies to characterize geographic and/or phenotypic associations of EBV variants with EBV-associated malignancies, including eBL.

15.
Int J Health Policy Manag ; 11(7): 1187-1196, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33906334

RESUMO

BACKGROUND: Emerging from a 20-year armed conflict, Uganda adopted several laws and policies to protect the rights of people with disabilities, including their sexual and reproductive health (SRH) rights. However, the SRH rights of people with disabilities continue to be infringed in Uganda. We explored policy actors' perceptions of existing pro-disability legislation and policy implementation, their perceptions of potential barriers experienced by people with disabilities in accessing and using SRH services in post-conflict Northern Uganda, and their recommendations on how to redress these inequities. METHODS: Through an intersectionality-informed approach, we conducted and thematically analysed 13 in-depth semi-structured interviews with macro level policy actors (national policy-makers and international and national organisations); seven focus groups (FGs) at meso level with 68 health service providers and representatives of disabled people's organisations (DPOs); and a two-day participatory workshop on disability-sensitive health service provision for 34 healthcare providers. RESULTS: We identified four main themes: (1) legislation and policy implementation was fraught with numerous technical and financial challenges, coupled with lack of prioritisation of disability issues; (2) people with disabilities experienced multiple physical, attitudinal, communication, and structural barriers to access and use SRH services; (3) the conflict was perceived to have persisting impacts on the access to services; and (4) policy actors recommended concrete solutions to reduce health inequities faced by people with disabilities. CONCLUSION: This study provides substantial evidence of the multilayered disadvantages people with disabilities face when using SRH services and the difficulty of implementing disability-focused policy in Uganda. Informed by an intersectionality approach, policy actors were able to identify concrete solutions and recommendations beyond the identification of problems. These recommendations can be acted upon in a practical road map to remove different types of barriers in the access to SRH services by people with disabilities, irrespective of their geographic location in Uganda.


Assuntos
Pessoas com Deficiência , Serviços de Saúde Reprodutiva , Humanos , Pesquisa Qualitativa , Acessibilidade aos Serviços de Saúde , Uganda , Enquadramento Interseccional , Saúde Reprodutiva
16.
Front Oncol ; 11: 804083, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34970500

RESUMO

Endemic Burkitt lymphoma (eBL) is the most common childhood cancer in regions of equatorial Africa where P. falciparum malaria is holoendemic. The tumor is consistently associated with Epstein-Barr virus (EBV). Screening for EBV DNA in plasma in a high-risk population in Hong Kong has been shown to be useful in facilitating the early diagnosis of nasopharyngeal carcinoma, another EBV-associated tumor. Here, we investigate plasma EBV as a diagnostic marker for eBL in children in Uganda. We studied plasma specimens from 25 children with eBL and 25 controls matched for age (<3-16 years), gender and geography, including many with asymptomatic P. falciparum infection. These specimens were previously collected under the auspices of the EMBLEM (Epidemiology of Burkitt lymphoma in East African children and minors) study. After cell-free DNA isolation, plasma EBV DNA was measured using a quantitative PCR assay that amplifies the large internal repeats of the EBV genome. All children with eBL had measurable plasma EBV, as compared to 84% of control children. The median plasma EBV DNA level was 5.23 log10 copies/mL (interquartile range 3.54-6.08 log10 copies/mL) in children with eBL. In contrast, the median plasma EBV DNA level was 0.37 log10 copies/mL (interquartile range 0.18-1.05 log10 copies/mL) in children without lymphoma. An EBV threshold of 2.52 log10 copies/mL yielded a sensitivity of.88 and a specificity of 1. The estimated AUC was 0.936 (95% CI: 0.8496 - 1.00) for the corresponding ROC curve. Plasma EBV copy number did not depend on age, gender, or malaria screening status. However, two control children with asymptomatic P. falciparum infection and parasitemia also had high plasma EBV copy number. Our analysis suggests that measurements of EBV copy number in plasma may be useful in identifying children with eBL versus control children. A promising area for future research is the differentiation of high copy number associated with tumor versus high copy number associated with asymptomatic parasitemia.

17.
BMC Infect Dis ; 21(1): 1175, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34809602

RESUMO

INTRODUCTION: Globally anti-tuberculosis drug resistance is one of the major challenges affecting control and prevention of tuberculosis. Kenya is ranked among 30 high burden TB countries globally. However, there is scanty information on second line antituberculosis drug resistance among tuberculosis patients. Therefore, this study aimed at determining Mycobacterium tuberculosis drug resistant strain distribution pattern in 10 counties of Western Kenya among HIV positive and negative patients. METHOD: A cross-sectional study was conducted in Western Kenya, which comprises 10 counties. A multistage sampling method was used where a single sub-county was randomly selected followed by sampling one high volume health facility from each sub-county. Consenting study subjects with at least two smear positive sputum at the time of enrolment were randomly selected. The collected sputum was decontaminated with N-acetyl-L-cysteine-sodium hydroxide (NALC-NaOH) and then stained with Ziehl Neelsen Stain before visualizing the presence of bacilli under microscope at ×100 magnification with oil immersion. Further, the identified bacilli were cultured and susceptibility test carried out using known first and second line antimycobacterial tuberculosis. HIV testing was carried out using Determine® HIV-1/2 rapid test (Abbot Diagnostics, Maidenhead, United Kingdom). Those who had smear converted were dropped from the study. Finally, drug susceptibility pattern across the 10 counties of Western Kenya was evaluated. RESULTS: Our study showed that Mycobacterium tuberculosis drug resistance among HIV negative and positive cases in Western Kenya was prevalent in all the 10 counties surveyed. Based on the drug susceptibility tests, 53.2% and 42.7% of the study samples were resistant to at least one antituberculosis drug among HIV negative and HIV positive patients respectively. The data analysis revealed that among the HIV-positive and HIV-negative patients, resistance to INH was predominant (28.5%, and 23.6%, respectively), followed by RIF (16.4% and 14.6% respectively). Second-line drug resistant strains identified among HIV negative patients included Ethionamide (0.3%), Gatifloxacin (0.3%), Amikacin (0.3%) and Capreomycin (0.3%). There was no second line drug monoresistance among HIV positive TB patients. Multi/poly drug resistance were noted among HIV-negative patients in, INH + AMK (0.7%), INH + PZA (1%), INH + GFX (0.7%, INH + ETO (0.7%, STY + ETO (1%), ETH + ETO (1.0%), INH + KAN (0.7%) and INH + CAP (0.7%) strains/cases at 95% confidence interval. Among HIV positive patients INH + GFX (1.1%), INH + ETO (0.4%) and INH + KAN (0.4%) strains of M. tuberculosis were identified with a confidence interval of 95%. Geographical distribution patterns analysis of M. tuberculosis drug polyresistant strains across the 10 counties were recorded. Among HIV TB patients, resistant strains were identified in Nyamira (INH + GFX, INH + KAN), Bungoma ((ETO + STY), Busia (ETH + ETO and STY + ETO) Homabay (RIF + AMK. ETO + ETH and ETO + STY), Kisumu (ETH + ETO and PZA + ETO) and in Kakamega, Kisii and Vihiga (INH + KAN and RIF + AMK). There was no M. tuberculosis polyresistant strain identified in Migori and Siaya counties. Among HIV positive TB patients, M. tuberculosis resistant strains were identified in three counties, Nyamira (INH + KAN) Homabay (INH + GFX and INH + AMK) and Kakamega (INH + GFX). There was no polyresistant M. tuberculosis strain identified in Migori, Bungoma, Kisii, Vihiga, Busia, Siaya and Kisumu Counties. DISCUSSION: The distribution patterns of M. tuberculosis drug resistance among HIV negative and positive TB patients could be as a result of reported high prevalence of HIV in Western Kenya counties especially the area under study. Tuberculosis is one of the opportunistic diseases that have been shown to be the major cause of AIDS among HIV infected patients. Resent reports by National AIDS Control Council shows that Kisumu, Siaya, Homabay, Migori, Busia have the overall leading in HIV prevalence in Kenya. The low prevalence of drug resistant strains among HIV tuberculosis patients could be as a result of drug adherence attitude adopted by HIV patients, availability of continuous counselling and close follow up and notification by healthcare workers and community health volunteers. CONCLUSION: Drug resistant M. tuberculosis strains prevalence is still high among HIV negative and positive patients in Western Kenya with the most affected being HIV negative TB patients. It is therefore probable that the existing control measures are not adequate to control transmission of drug resistant strains. Further, miss diagnosis or delayed diagnosis of TB patients could be contributing to the emergence of M. tuberculosis drug polyresistant strains. RECOMMENDATION: Based on the result of this study, regular TB drug resistance surveillance should be conducted to ensure targeted interventions aimed at controlling increased transmission of the tuberculosis drug resistant strains among HIV/AIDS and HIV negative patients. There is also need for improved drug resistant infection control measures, timely and rapid diagnosis and enhanced and active screening strategies of tuberculosis among suspected TB patients need to be put in place. Further, studies using a larger patient cohort and from counties across the country would shed much needed insights on the true national prevalence of different variants of M. tuberculosis drug resistance.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Estudos Transversais , Resistência a Medicamentos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Quênia/epidemiologia , Testes de Sensibilidade Microbiana , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia
18.
N Engl J Med ; 385(13): 1163-1171, 2021 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-34551228

RESUMO

BACKGROUND: In the six Southeast Asian countries that make up the Greater Mekong Subregion, Plasmodium falciparum has developed resistance to derivatives of artemisinin, the main component of first-line treatments for malaria. Clinical resistance to artemisinin monotherapy in other global regions, including Africa, would be problematic. METHODS: In this longitudinal study conducted in Northern Uganda, we treated patients who had P. falciparum infection with intravenous artesunate (a water-soluble artemisinin derivative) and estimated the parasite clearance half-life. We evaluated ex vivo susceptibility of the parasite using a ring-stage survival assay and genotyped resistance-related genes. RESULTS: From 2017 through 2019, a total of 14 of 240 patients who received intravenous artesunate had evidence of in vivo artemisinin resistance (parasite clearance half-life, >5 hours). Of these 14 patients, 13 were infected with P. falciparum parasites with mutations in the A675V or C469Y allele in the kelch13 gene. Such mutations were associated with prolonged parasite clearance half-lives (geometric mean, 3.95 hours for A675V and 3.30 hours for C469Y, vs. 1.78 hours for wild-type allele; P<0.001 and P = 0.05, respectively). The ring-stage survival assay showed a higher frequency of parasite survival among organisms with the A675V allele than among those with the wild-type allele. The prevalence of parasites with kelch13 mutations increased significantly, from 3.9% in 2015 to 19.8% in 2019, due primarily to the increased frequency of the A675V and C469Y alleles (P<0.001 and P = 0.004, respectively). Single-nucleotide polymorphisms flanking the A675V mutation in Uganda were substantially different from those in Southeast Asia. CONCLUSIONS: The independent emergence and local spread of clinically artemisinin-resistant P. falciparum has been identified in Africa. The two kelch13 mutations may be markers for detection of these resistant parasites. (Funded by the Japan Society for the Promotion of Science and others.).


Assuntos
Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Resistência a Medicamentos/genética , Malária Falciparum/tratamento farmacológico , Mutação , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Humanos , Estudos Longitudinais , Polimorfismo de Nucleotídeo Único , Uganda
19.
Clin Case Rep ; 9(7): e04510, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34295498

RESUMO

Cholecystocolonic fistula is a rare condition often diagnosed intraoperatively, requiring an adequate set of knowledge and skills to allow safe intraoperative change of prior planned surgery and alleviate significant morbidity.

20.
Surgery ; 170(5): 1397-1404, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34130809

RESUMO

BACKGROUND: Significant limitations in pediatric surgical capacity exist in low- and middle-income countries, especially in rural regions. Recent global children's surgical guidelines suggest training and support of general surgeons in rural regional hospitals as an effective approach to increasing pediatric surgical capacity. METHODS: Two years of a prospective clinical database of children's surgery admissions at 2 regional referral hospitals in Uganda were reviewed. Primary outcomes included case volume and clinical outcomes of children at each hospital. Additionally, the disability-adjusted life-years averted by delivery of pediatric surgical services at these hospitals were calculated. Using a value of statistical life calculation, we also estimated the economic benefit of the pediatric surgical care currently being delivered. RESULTS: From 2016 to 2019, more than 300 surgical procedures were performed at each hospital per year. The majority of cases were standard general surgery cases including hernia repairs and intussusception as well as procedures for surgical infections and trauma. In-hospital mortality was 2.4% in Soroti and 1% in Lacor. Pediatric surgical capacity at these hospitals resulted in over 12,400 disability-adjusted life-years averted/year. This represents an estimated economic benefit of 10.2 million US dollars/year to the Ugandan society. CONCLUSION: This investigation demonstrates that lifesaving pediatric procedures are safely performed by general surgeons in Uganda. General surgeons who perform pediatric surgery significantly increase surgical access to rural regions of the country and add a large economic benefit to Ugandan society. Overall, the results of the study support increasing pediatric surgical capacity in rural areas of low- and middle-income countries through support and training of general surgeons and anesthesia providers.


Assuntos
Anestesiologistas/provisão & distribuição , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Hospitais Pediátricos/provisão & distribuição , Hospitais Rurais/provisão & distribuição , Cirurgiões/provisão & distribuição , Procedimentos Cirúrgicos Operatórios/tendências , Criança , Pré-Escolar , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Procedimentos Cirúrgicos Operatórios/mortalidade , Uganda/epidemiologia
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