RESUMEN
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.
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Linfoma de Burkitt , Malaria Falciparum , Malaria , Humanos , Linfoma de Burkitt/epidemiología , Linfoma de Burkitt/genética , Plasmodium falciparum , Estudios de Casos y Controles , Uganda/epidemiología , Kenia/epidemiología , Tanzanía/epidemiología , Estudios Transversales , Malaria Falciparum/complicaciones , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Malaria/epidemiologíaRESUMEN
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.
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Linfoma de Burkitt , Infecciones por Virus de Epstein-Barr , Linfoma de Células B Grandes Difuso , Niño , Humanos , Adulto , Linfoma de Burkitt/patología , Herpesvirus Humano 4 , Linfoma de Células B Grandes Difuso/patología , MutaciónRESUMEN
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.).
Asunto(s)
Antimaláricos/uso terapéutico , Artemisininas/uso terapéutico , Resistencia a Medicamentos/genética , Malaria Falciparum/tratamiento farmacológico , Mutación , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Humanos , Estudios Longitudinales , Polimorfismo de Nucleótido Simple , UgandaRESUMEN
INTRODUCTION: Burkitt lymphoma (BL) is an aggressive non-Hodgkin lymphoma associated with Plasmodium falciparum and Epstein-Barr virus, both of which affect metabolic pathways. The metabolomic patterns of BL is unknown. MATERIALS AND METHODS: We measured 627 metabolites in pre-chemotherapy treatment plasma samples from 25 male children (6-11 years) with BL and 25 cancer-free area- and age-frequency-matched male controls from the Epidemiology of Burkitt Lymphoma in East African Children and Minors study in Uganda using liquid chromatography-tandem mass spectrometry. Unconditional, age-adjusted logistic regression analysis was used to estimate odds ratios (ORs) and their 95% confidence intervals (CIs) for the BL association with 1-standard deviation increase in the log-metabolite concentration, adjusting for multiple comparisons using false discovery rate (FDR) thresholds and Bonferroni correction. RESULTS: Compared to controls, levels for 42 metabolite concentrations differed in BL cases (FDR < 0.001), including triacylglyceride (18:0_38:6), alpha-aminobutyric acid (AABA), ceramide (d18:1/20:0), phosphatidylcholine ae C40:6 and phosphatidylcholine C38:6 as the top signals associated with BL (ORs = 6.9 to 14.7, P < 2.4â10- 4). Two metabolites (triacylglyceride (18:0_38:6) and AABA) selected using stepwise logistic regression discriminated BL cases from controls with an area under the curve of 0.97 (95% CI: 0.94, 1.00). CONCLUSION: Our findings warrant further examination of plasma metabolites as potential biomarkers for BL risk/diagnosis.
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Linfoma de Burkitt , Metabolómica , Humanos , Linfoma de Burkitt/sangre , Linfoma de Burkitt/metabolismo , Niño , Uganda/epidemiología , Masculino , Estudios de Casos y Controles , Metabolómica/métodos , Metaboloma , FemeninoRESUMEN
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.
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Linfoma de Burkitt , Malaria Falciparum , Malaria , Rasgo Drepanocítico , Humanos , África Oriental , Alelos , Linfoma de Burkitt/epidemiología , Linfoma de Burkitt/genética , Malaria Falciparum/epidemiología , Malaria Falciparum/genética , Malaria Falciparum/complicaciones , Rasgo Drepanocítico/epidemiología , Rasgo Drepanocítico/genética , Rasgo Drepanocítico/complicaciones , Nectinas/metabolismoRESUMEN
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.
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Antimaláricos , Artemisininas , Malaria Falciparum , Parásitos , Animales , Humanos , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Parasitemia/tratamiento farmacológico , Resistencia a Medicamentos , Artemisininas/farmacología , Artemisininas/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Plasmodium falciparum/genética , Uganda/epidemiología , Proteínas Protozoarias/genéticaRESUMEN
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.
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Especialidades Quirúrgicas , Adulto , Humanos , Niño , Uganda/epidemiología , Hospitales , Análisis Costo-Beneficio , Necesidades y Demandas de Servicios de SaludRESUMEN
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.
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Seropositividad para VIH , Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Humanos , Mycobacterium tuberculosis/genética , Estudios Transversales , Kenia/epidemiología , Epidemiología Molecular , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , GenotipoRESUMEN
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.
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ADN Tumoral Circulante , Linfoma no Hodgkin , Neoplasias , África Oriental , Biomarcadores de Tumor/genética , Niño , Herpesvirus Humano 4/genética , Humanos , Biopsia Líquida/métodos , Neoplasias/diagnóstico , Adulto JovenRESUMEN
Populations in sub-Saharan Africa have historically been exposed to intense selection from chronic infection with falciparum malaria. Interestingly, populations with the highest malaria intensity can be identified by the increased occurrence of endemic Burkitt Lymphoma (eBL), a pediatric cancer that affects populations with intense malaria exposure, in the so called "eBL belt" in sub-Saharan Africa. However, the effects of intense malaria exposure and sub-Saharan populations' genetic histories remain poorly explored. To determine if historical migrations and intense malaria exposure have shaped the genetic composition of the eBL belt populations, we genotyped ~4.3 million SNPs in 1,708 individuals from Ghana and Northern Uganda, located on opposite sides of eBL belt and with ≥ 7 months/year of intense malaria exposure and published evidence of high incidence of BL. Among 35 Ghanaian tribes, we showed a predominantly West-Central African ancestry and genomic footprints of gene flow from Gambian and East African populations. In Uganda, the North West population showed a predominantly Nilotic ancestry, and the North Central population was a mixture of Nilotic and Southern Bantu ancestry, while the Southwest Ugandan population showed a predominant Southern Bantu ancestry. Our results support the hypothesis of diverse ancestral origins of the Ugandan, Kenyan and Tanzanian Great Lakes African populations, reflecting a confluence of Nilotic, Cushitic and Bantu migrations in the last 3000 years. Natural selection analyses suggest, for the first time, a strong positive selection signal in the ATP2B4 gene (rs10900588) in Northern Ugandan populations. These findings provide important baseline genomic data to facilitate disease association studies, including of eBL, in eBL belt populations.
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Linfoma de Burkitt/genética , Flujo Génico , Malaria Falciparum/genética , Selección Genética , Adolescente , África del Sur del Sahara , Anciano , Linfoma de Burkitt/epidemiología , Estudios de Casos y Controles , Niño , Preescolar , Enfermedades Endémicas , Femenino , Genética de Población , Estudio de Asociación del Genoma Completo , Ghana/epidemiología , Migración Humana , Humanos , Incidencia , Lactante , Recién Nacido , Malaria Falciparum/epidemiología , Masculino , Persona de Mediana Edad , Modelos Genéticos , ATPasas Transportadoras de Calcio de la Membrana Plasmática/genética , Polimorfismo de Nucleótido Simple , Uganda/epidemiologíaRESUMEN
Although generally curable with intensive chemotherapy in resource-rich settings, Burkitt lymphoma (BL) remains a deadly disease in older patients and in sub-Saharan Africa. Epstein-Barr virus (EBV) positivity is a feature in more than 90% of cases in malaria-endemic regions, and up to 30% elsewhere. However, the molecular features of BL have not been comprehensively evaluated when taking into account tumor EBV status or geographic origin. Through an integrative analysis of whole-genome and transcriptome data, we show a striking genome-wide increase in aberrant somatic hypermutation in EBV-positive tumors, supporting a link between EBV and activation-induced cytidine deaminase (AICDA) activity. In addition to identifying novel candidate BL genes such as SIN3A, USP7, and CHD8, we demonstrate that EBV-positive tumors had significantly fewer driver mutations, especially among genes with roles in apoptosis. We also found immunoglobulin variable region genes that were disproportionally used to encode clonal B-cell receptors (BCRs) in the tumors. These include IGHV4-34, known to produce autoreactive antibodies, and IGKV3-20, a feature described in other B-cell malignancies but not yet in BL. Our results suggest that tumor EBV status defines a specific BL phenotype irrespective of geographic origin, with particular molecular properties and distinct pathogenic mechanisms. The novel mutation patterns identified here imply rational use of DNA-damaging chemotherapy in some patients with BL and targeted agents such as the CDK4/6 inhibitor palbociclib in others, whereas the importance of BCR signaling in BL strengthens the potential benefit of inhibitors for PI3K, Syk, and Src family kinases among these patients.
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Biomarcadores de Tumor/genética , Linfoma de Burkitt/genética , Infecciones por Virus de Epstein-Barr/complicaciones , Genes de Inmunoglobulinas , Genoma Humano , Mutación , Transcriptoma , Adolescente , Adulto , Linfoma de Burkitt/patología , Linfoma de Burkitt/virología , Niño , Preescolar , Estudios de Cohortes , Citidina Desaminasa/genética , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/virología , Femenino , Estudios de Seguimiento , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Lactante , Recién Nacido , Masculino , Fenotipo , Pronóstico , Adulto JovenRESUMEN
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.
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Infecciones por VIH , Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Antituberculosos/farmacología , Antituberculosos/uso terapéutico , Estudios Transversales , Resistencia a Medicamentos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Kenia/epidemiología , Pruebas de Sensibilidad Microbiana , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/epidemiologíaRESUMEN
BACKGROUND: Community participatory interventions mobilizing women of childbearing age are an effective strategy to promote maternal and child health. In 2017, we implemented this strategy in Gulu Northern Uganda. This study explored the perceived impact of this approach on women's capability. METHODS: We conducted a qualitative study based on three data collection methods: 14 in-depth individual interviews with participating women of childbearing age, five focus group discussions with female facilitators, and document analysis. We used the Sen capability approach as a conceptual framework and undertook a thematic analysis. RESULTS: Women adopted safe and healthy behaviors for themselves and their children. They were also able to respond to some of their family's financial needs. They reported a reduction in domestic violence and in mistreatment towards their children. The facilitators perceived improved communication skills, networking, self-confidence, and an increase in their social status. Nevertheless, the women still faced unfreedoms that deprived them of living the life they wanted to lead. These unfreedoms are related to their lack of access to economic opportunities and socio-cultural norms underlying gender inequalities. CONCLUSION: To expand women's freedoms, we need more collective political actions to tackle gender inequalities and need to question the values underlying women's social status.
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Identidad de Género , Derechos de la Mujer , Niño , Femenino , Grupos Focales , Humanos , Investigación Cualitativa , UgandaRESUMEN
BACKGROUND: Short birth interval is associated with adverse perinatal, maternal, and infant outcomes, although evidence on actionable factors underlying short birth interval remains limited. We explored women and community views on short birth intervals to inform potential solutions to promote a culturally safe child spacing in Northern Uganda. METHODS: Gendered fuzzy cognitive mapping sessions (n = 21), focus group discussions (n = 12), and an administered survey questionnaire (n = 255) generated evidence on short birth intervals. Deliberative dialogues with women, their communities, and service providers suggested locally relevant actions promote culturally safe child spacing. RESULTS: Women, men, and youth have clear understandings of the benefits of adequate child spacing. This knowledge is difficult to translate into practice as women are disempowered to exercise child spacing. Women who use contraceptives without their husbands' consent risk losing financial and social assets and are likely to be subject to intra-partner violence. Women were not comfortable with available contraceptive methods and reported experiencing well-recognized side effects. They reported anxiety about the impact of contraception on the health of their future children. This fear was fed by rumors in their communities about the effects of contraceptives on congenital diseases. The women and their communities suggested a home-based sensitization program focused on improving marital relationships (spousal communication, mutual understanding, male support, intra-partner violence) and knowledge and side-effects management of contraceptives. CONCLUSIONS: The economic context, gender power dynamics, inequality, gender bias in land tenure and ownership regulations, and the limited contraceptive supply reduce women's capacity to practice child spacing.
The evidence on what increases birth spacing remains limited. This study explored community views on influences on short birth interval to promote a culturally safe child spacing in Northern Uganda. A participatory research process began by collating perspectives of causes of short birth intervals through fuzzy cognitive mapping. Focus group discussions clarified concepts emerging from the fuzzy cognitive mapping exercise. Fieldworkers administered a household survey to quantify reproductive health outcomes. In deliberative dialogue sessions involving women and their communities, shared and discussed these results and suggested potential actions to promote culturally safe child spacing. Women, men, and youth showed clear understandings of the benefits of adequate child spacing. This knowledge is difficult to translate into practice, however, as women feel they are unable to exercise child spacing. Women who use contraceptives without their husbands' consent risk losing financial and social resources and are likely to face intra-partner violence. Women were not comfortable with contraceptive methods and reported experiencing side effects. The deliberative dialogues suggested a home-based sensitization program focused on improving marital relationships (spousal communication, mutual understanding, male support, intra-partner violence) and knowledge and side-effects management of contraceptives.
Asunto(s)
Intervalo entre Nacimientos , Conducta Anticonceptiva , Anticoncepción/estadística & datos numéricos , Adolescente , Adulto , Niño , Investigación Participativa Basada en la Comunidad , Femenino , Teoría Fundamentada , Humanos , Masculino , Matrimonio , Edad Materna , Embarazo , Salud Reproductiva , Sexismo , Normas Sociales , UgandaRESUMEN
Endemic Burkitt lymphoma (eBL) is the most common childhood cancer in sub-Saharan African countries, however, few epidemiologic studies have been undertaken and none attempted enrolling cases from multiple countries. We therefore conducted a population-based case-control study of eBL in children aged 0-15 years old in six regions in Northern Uganda, Northern Tanzania and Western Kenya, enrolling 862 suspected cases and 2,934 population controls (response rates 98.5-100%), and processing ~40,000 vials of samples using standardized protocols. Risk factor questionnaires were administered, and malaria period prevalence was measured using rapid diagnostic tests (RDTs). A total of 80.9% of the recruited cases were diagnosed as eBL; 61.4% confirmed by histology. Associations with eBL risk were computed using logistic regression models adjusted for relevant confounders. Associations common in at least two countries were emphasized. eBL risk was decreased with higher maternal income and paternal education and elevated with history of inpatient malaria treatment >12 months before enrollment. Reporting malaria-attributed fever up to 6 months before enrollment and malaria-RDT positivity at enrollment were associated with decreased eBL risk. Conversely, reporting exposure to mass malaria suppression programs (e.g., indoor residual insecticide) was associated with elevated risk. HIV seropositivity was associated with elevated eBL risk, but the relative impact was small. The study shows that it is feasible to conduct networked, multisite population-based studies of eBL in Africa. eBL was inversely associated with socioeconomic status, positively associated with inpatient malaria treatment 12 months ago and with living in areas targeted for malaria suppression, which support a role of malaria in eBL.
Asunto(s)
Linfoma de Burkitt/epidemiología , Enfermedades Endémicas/estadística & datos numéricos , Seropositividad para VIH/epidemiología , Malaria/epidemiología , Factores Socioeconómicos , Adolescente , Linfoma de Burkitt/etiología , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Seropositividad para VIH/complicaciones , Humanos , Lactante , Recién Nacido , Kenia/epidemiología , Malaria/complicaciones , Malaria/diagnóstico , Masculino , Prevalencia , Factores de Riesgo , Encuestas y Cuestionarios/estadística & datos numéricos , Tanzanía/epidemiología , Uganda/epidemiologíaRESUMEN
Platelet counts are decreased in Plasmodium falciparum malaria, which is aetiologically linked with endemic Burkitt lymphoma (eBL). However, the pattern of platelet counts in eBL cases is unknown. We studied platelet counts in 582 eBL cases and 2 248 controls enrolled in a case-control study in Uganda, Tanzania and Kenya (2010-2016). Mean platelet counts in controls or eBL cases with or without malaria-infection in controls versus eBLcases were compared using Student's t-test. Odds ratios (ORs) and two-sided 95% confidence intervals (95% CIs) were estimated using multiple logistic regression, controlling for age, sex, haemoglobin and white blood cell counts. Platelets were decreased with malaria infection in the controls [263 vs. 339 × 109 platelets/l, P < 0·0001; adjusted OR (aOR) = 3·42, 95% CI: 2·79-4·18] and eBL cases (314 vs. 367 × 109 platelets/l, P-value = 0·002; aOR = 2·36, 95% CI: 1·49-3·73). Unexpectedly, platelets were elevated in eBL cases versus controls in overall analyses (mean: 353 vs. 307 × 109 platelets/l, P < 0·0001; aOR = 1·41; 95% CI: 1·12-1·77), and when restricted to malaria-positive (mean 314 vs. 263 × 109 platelets/l, P < 0·0001; OR = 2·26; 95% CI: 1·56-3·27) or malaria-negative (mean 367 vs. 339 × 109 platelets/l, P < 0·001; OR = 1·46; 95% CI: 1·17-1·83) subjects. Platelets were decreased with malaria infection in controls and eBL cases but elevated with eBL.
Asunto(s)
Linfoma de Burkitt/sangre , Malaria/sangre , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Kenia , Masculino , Recuento de Plaquetas , Tanzanía , UgandaRESUMEN
Endemic Burkitt lymphoma (eBL) is an aggressive childhood B-cell lymphoma associated with Plasmodium falciparum (Pf) malaria and Epstein-Barr virus (EBV) infections. Variation in the Human Leukocyte Antigen (HLA) system is suspected to play a role, but assessments using less accurate serology-based HLA typing techniques in small studies yielded conflicting results. We studied 200 eBL cases and 400 controls aged 0-15 years enrolled in northern Uganda and typed by accurate high-resolution HLA sequencing methods. HLA results were analyzed at one- or two-field resolution. Odds ratios and 95% confidence intervals (aOR, 95% CI) for eBL risk associated with common HLA alleles versus alleles that were rare (<1%) or differed by <2% between the cases and controls as the reference category, were estimated using multiple logistic regression adjusting for age, sex, microgeography, region, malaria positivity and treatment history, and genetic variants associated with eBL. Compared to the controls, eBL cases had a lower frequency of HLA-A*02 (aOR = 0·59, 95% CI 0·38-0·91), HLA-B*41 (aOR = 0·36, 95% CI 0·13-1·00), and HLA-B*58 alleles (aOR = 0·59, 95% CI 0·36-0·97). eBL cases had a lower frequency of HLA-DPB1 homozygosity (aOR = 0·57, 95% CI 0·40-0·82) but a higher frequency of HLA-DQA1 homozygosity (aOR = 2·19, 95% CI 1·42-3·37). Our results suggest that variation in HLA may be associated with eBL risk.
Asunto(s)
Linfoma de Burkitt/sangre , Antígenos HLA/metabolismo , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Factores de Riesgo , UgandaRESUMEN
BACKGROUND: Endemic Burkitt lymphoma (eBL) is an aggressive B cell non-Hodgkin lymphoma associated with antigenic stimulation from Plasmodium falciparum malaria. Whether eBL risk is related to malaria parasite density is unknown. To address this issue, children with eBL, asymptomatic and clinical malaria, as a surrogate of malaria parasite density, were assessed. METHODS: Malaria-related laboratory results (parasite density, haemoglobin, platelet count, and white cell count [WBC]) count) were compiled for 4019 eBL cases and 80,532 subjects evaluated for asymptomatic malaria or clinical malaria (severe malaria anaemia, hyperparasitaemia, cerebral malaria, malaria prostration, moderate malaria, and mild malaria) in 21 representative studies published in Africa (mostly East Africa) and 850 eBL cases and 2878 controls with primary data from the Epidemiology of Burkitt Lymphoma in East African Children and Minors (EMBLEM) case-control study in Uganda, Tanzania, and Kenya. The average values of malaria-related laboratory results were computed by condition and trends across single-year age groups were assessed using regression and spline models. RESULTS: Overall, malaria infection or malaria was diagnosed in 37,089 of children compiled from the literature. Children with eBL and asymptomatic parasitaemia/antigenaemia, but not those with clinical malaria, were closest in their mean age (age 7.1-7.2 vs. 7.4-9.8 years), haemoglobin level (10.0-10.4 vs. 11.7-12.3 g/dL), malaria parasite density (2800 vs. 1827-7780 parasites/µL), platelet count (347,000-353,000 vs. 244,000-306,000 platelets/µL), and WBC count (8180-8890 vs. 7100-7410 cells/µL). Parasite density in these two groups peaked between four to five years, then decreased steadily thereafter; conversely, haemoglobin showed a corresponding increase with age. Children with clinical malaria were markedly different: all had an average age below 5 years, had dramatically elevated parasite density (13,905-869,000 parasites/µL) and dramatically decreased platelet count (< 159,000 platelets/µL) and haemoglobin (< 7 g/dL). CONCLUSIONS: eBL and asymptomatic parasitaemia/antigenaemia, but not clinical malaria, were the most similar conditions with respect to mean age and malaria-related laboratory results. These results suggest that children with asymptomatic parasitaemia/antigenaemia may be the population at risk of eBL.
Asunto(s)
Linfoma de Burkitt/epidemiología , Malaria Falciparum/epidemiología , Adolescente , Infecciones Asintomáticas/epidemiología , Linfoma de Burkitt/parasitología , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Kenia/epidemiología , Malaria Falciparum/complicaciones , Malaria Falciparum/parasitología , Masculino , Plasmodium falciparum/fisiología , Prevalencia , Tanzanía/epidemiología , Uganda/epidemiologíaRESUMEN
BACKGROUND: Usage of chloroquine was discontinued from the treatment of Plasmodium falciparum infection in almost all endemic regions because of global spread of resistant parasites. Since the first report in Malawi, numerous epidemiological studies have demonstrated that the discontinuance led to re-emergence of chloroquine-susceptible P. falciparum, suggesting a possible role in future malaria control. However, most studies were cross-sectional, with few studies looking at the persistence of chloroquine recovery in long term. This study fills the gap by providing, for a period of at least 6 years, proof of persistent re-emergence/stable recovery of susceptible parasite populations using both molecular and phenotypic methods. METHODS: Ex vivo drug-susceptibility assays to chloroquine (n = 319) and lumefantrine (n = 335) were performed from 2013 to 2018 in Gulu, Northern Uganda, where chloroquine had been removed from the official malaria treatment regimen since 2006. Genotyping of pfcrt and pfmdr1 was also performed. RESULTS: Chloroquine resistance (≥ 100 nM) was observed in only 3 (1.3%) samples. Average IC50 values for chloroquine were persistently low throughout the study period (17.4-24.9 nM). Parasites harbouring pfcrt K76 alleles showed significantly lower IC50s to chloroquine than the parasites harbouring K76T alleles (21.4 nM vs. 43.1 nM, p-value = 3.9 × 10-8). Prevalence of K76 alleles gradually increased from 71% in 2013 to 100% in 2018. CONCLUSION: This study found evidence of stable persistence of chloroquine susceptibility with the fixation of pfcrt K76 in Northern Uganda after discontinuation of chloroquine in the region. Accumulation of similar evidence in other endemic areas in Uganda could open channels for possible future re-use of chloroquine as an option for malaria treatment or prevention.
Asunto(s)
Antimaláricos/farmacología , Cloroquina/farmacología , Resistencia a Medicamentos , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/genética , UgandaRESUMEN
BACKGROUND: There is a significant unmet need for children's surgical care in low- and middle-income countries (LMICs). Multidisciplinary collaboration is required to advance the surgical and anesthesia care of children's surgical conditions such as congenital conditions, cancer and injuries. Nonetheless, there are limited examples of this process from LMICs. We describe the development and 3-year outcomes following a 2015 stakeholders' meeting in Uganda to catalyze multidisciplinary and multi-institutional collaboration. METHODS: The stakeholders' meeting was a daylong conference held in Kampala with local, regional and international collaborators in attendance. Multiple clinical specialties including surgical subspecialists, pediatric anesthesia, perioperative nursing, pediatric oncology and neonatology were represented. Key thematic areas including infrastructure, training and workforce retention, service delivery, and research and advocacy were addressed, and short-term objectives were agreed upon. We reported the 3-year outcomes following the meeting by thematic area. RESULTS: The Pediatric Surgical Foundation was developed following the meeting to formalize coordination between institutions. Through international collaborations, operating room capacity has increased. A pediatric general surgery fellowship has expanded at Mulago and Mbarara hospitals supplemented by an international fellowship in multiple disciplines. Coordinated outreach camps have continued to assist with training and service delivery in rural regional hospitals. CONCLUSION: Collaborations between disciplines, both within LMICs and with international partners, are required to advance children's surgery. The unification of stakeholders across clinical disciplines and institutional partnerships can facilitate increased children's surgical capacity. Such a process may prove useful in other LMICs with a wide range of children's surgery stakeholders.