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1.
BMC Public Health ; 18(1): 193, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29378631

RESUMO

BACKGROUND: Substance use is increasingly becoming prevalent on the African continent, fueling the spread of HIV infection. Although socio-demographic factors influence substance consumption and risk of HIV infection, the association of these factors with HIV infection is poorly understood among substance users on the African continent. The objective of the study was to assess socio-demographic and sexual practices that are associated with HIV infection among injection drug users (IDUs), non-IDUs, and non-drug users (DUs) at an urban setting of coastal Kenya. METHODS: A cross-sectional descriptive study was conducted among 451 adults comprising HIV-infected and -uninfected IDUs (n = 157 and 39); non-IDUs (n = 17 and 48); and non-DUs (n = 55 and 135); respectively at coastal, Kenya. Respondent driven sampling, snowball and makeshift methods were used to enroll IDUs and non-IDUs. Convenience and purposive sampling were used to enroll non-DUs from the hospital's voluntary HIV testing unit. Participant assisted questionnaire was used in collecting socio-demographic data and sexual practices. RESULTS: Binary logistic regression analysis indicated that higher likelihood of HIV infection was associated with sex for police protection (OR, 9.526; 95% CI, 1.156-78.528; P = 0.036) and history of sexually transmitted infection (OR, 5.117; 95% CI, 1.924-13.485; P = 0.001) in IDUs; divorced, separated or widowed marital status (OR, 6.315; 95% CI, 1.334-29.898; P = 0.020) in non-IDUs; and unemployment (OR, 2.724; 95% CI, 1.049-7.070; P = 0.040) in non-drug users. However, never married (single) marital status (OR, 0.140; 95% CI, 0.030-0.649; P = 0.012) was associated with lower odds for HIV infection in non-drug users. CONCLUSION: Altogether, these results suggest that socio-demographic and sexual risk factors for HIV transmission differ with drug use status, suggesting targeted preventive measures for drug users.


Assuntos
Usuários de Drogas/psicologia , Usuários de Drogas/estatística & dados numéricos , Infecções por HIV/epidemiologia , Comportamento Sexual/estatística & dados numéricos , Abuso de Substâncias por Via Intravenosa/epidemiologia , Adulto , Estudos Transversais , Feminino , Humanos , Quênia/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Socioeconômicos
2.
BMC Infect Dis ; 17(1): 289, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28427365

RESUMO

BACKGROUND: Naturally-acquired immunity to Plasmodium falciparum malaria develops after several episodes of infection. Fc gamma receptors (FcγRs) bind to immunoglobulin G (IgG) antibodies and mediate phagocytosis of opsonized microbes, thereby, linking humoral and cellular immunity. FcγR polymorphisms influence binding affinity to IgGs and consequently, can influence clinical malaria outcomes. Specifically, variations in FcγRIIA -131Arg/His, FcγRIIIA-176F/V and FcγRIIIB-NA1/NA2 modulate immune responses through altered binding preferences to IgGs and immune complexes. Differential binding, in turn, changes ability of immune cells to respond to infection through production of inflammatory mediators during P. falciparum infection. METHODS: We determined the association between haplotypes of FcγRIIA-131Arg/His, FcγRIIIA-176F/V and FcγRIIIB-NA1/NA2 variants and severe malarial anemia (SMA; hemoglobin < 6.0 g/dL, any density parasitemia) in children (n = 274; aged 6-36 months) presenting for their first hospital visit with P. falciparum malaria in a holoendemic transmission region of western Kenya. FcγRIIA-131Arg/His and FcγRIIIA-176F/V genotypes were determined using TaqMan® SNP genotyping, while FcγRIIIBNA1/NA2 genotypes were determined using restriction fragment length polymorphism. Hematological and parasitological indices were measured in all study participants. RESULTS: Carriage of FcγRIIA-131Arg/FcγRIIIA-176F/FcγRIIIBNA2 haplotype was associated with susceptibility to SMA (OR = 1.70; 95% CI; 1.02-2.93; P = 0.036), while the FcγRIIA-131His/ FcγRIIIA-176F/ FcγRIIIB NA1 haplotype was marginally associated with enhanced susceptibility to SMA (OR: 1.80, 95% CI; 0.98-3.30, P = 0.057) and higher levels of parasitemia (P = 0.009). Individual genotypes of FcγRIIA-131Arg/His, FcγRIIIA-176F/V and FcγRIIIB-NA1/NA2 were not associated with susceptibility to SMA. CONCLUSION: The study revealed that haplotypes of FcγRs are important in conditioning susceptibility to SMA in immune-naive children from P. falciparum holoendemic region of western Kenya.


Assuntos
Anemia/genética , Malária/complicações , Polimorfismo Genético , Receptores de IgG/genética , Anemia/etiologia , Pré-Escolar , Estudos Transversais , Feminino , Proteínas Ligadas por GPI/genética , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Lactente , Quênia , Malária/genética , Malária Falciparum/sangue , Malária Falciparum/complicações , Masculino , Carga Parasitária , Polimorfismo de Fragmento de Restrição
3.
Afr J Reprod Health ; 20(1): 71-79, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29553179

RESUMO

Involvement of males in reproductive health is an important step in reducing maternal and newborn deaths. A number of pregnant women attending Coast Level Five Hospital report waiting for their male partner to discuss and choose the delivery site. Although some do this when already in labour , there are no records on how many practice this and the influence of the couple knowledge and perception on male partner involvement in choice of delivery site. This descriptive cross-sectional study aimed at establishing the level of male partner involvement and influence of couple knowledge and perception on male involvement in choice of delivery site among women who delivered at this facility. Systematic sampling was used to select the participants. A semi-structured questionnaire and focus group discussion guide were used to collect data. Chi-square and binary logistic regression were used for statistical analysis. 40.6% of male partners were involved in choice of delivery site, women knowledge (χ2-19.256; df-1; p<0.001), women (χ2-11.347; df-1; p=0.001) and male partners' perception (χ2-10.909; df-1; p=0.001) influenced male partner involvement. However, women knowledge was the only predictor of male involvement (OR-3.843; 95% CI, 2.082-7.092; P<0.001). Male partner involvement was low, empowering women and encouraging positive perception among women and male partners will enhance male partner involvement in choice of delivery site. The health workers in Mombasa should come up with health education and communication strategies to improve public knowledge and perception towards male involvement and ultimately improve the level of male partner involvement in choice of delivery site.

4.
BMC Infect Dis ; 15: 299, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26223795

RESUMO

BACKGROUND: Information about HBV sero-markers, infection stages and genotypes in HIV-1 infected and uninfected injection and non-injection drug users (IDUs) in Kenya remains elusive. METHODS: A cross-sectional study examining HBV sero-marker, infection stages and genotypes was conducted among HIV-1 infected and uninfected, respectively, IDUs (n = 157 and n = 214) and non-IDUs (n = 139 and n = 48), and HIV-1 uninfected non-drug using controls (n = 194) from coastal, Kenya. HBV sero-marker and infection stages were based on HBV 5-panel rapid test plasma sero-reactivity. DNA was extracted from acute and chronic plasma samples and genotypes established by nested-PCR and direct sequencing. RESULTS: HBsAg positivity was higher in HIV-1 infected IDUs (9.6%) relative to HIV-1 uninfected IDUs (2.3%), HIV-1 infected non-IDUs (3.6%), HIV-1 uninfected non-IDUs (0.0%) and non-drug users (2.6%; P = 0.002). Contrastingly, HBsAb positivity was higher in HIV-1 uninfected IDUs (14.6%) and non-IDUs (16.8) in comparison to HIV-1 infected IDUs (8.3%), and non-IDUs (8.6%), and non-drug users (8.2%; P = 0.023). HBcAb positivity was higher in HIV-1 infected IDUs (10.2%) compared to HIV-1 uninfected IDUs (3.3%), HIV-1 infected non-IDUs (6.5%), HIV-1 uninfected non-IDUs (2.1%) and non-drug users (4.6%; P = 0.038). Acute (5.7%, 1.4%, 0.0%, 0.0% and 1.5%) and chronic (5.1%, 0.9%, 3.6%, 0.0% and 1.5%) stages were higher in HIV-1 infected IDUs, compared to HIV-1 uninfected IDUs, HIV-1 infected and uninfected non-IDUs and non-drug users, respectively. However, vaccine type response stage was higher in HIV-1 uninfected IDUs (15.4%) relative to HIV-1 infected IDUs (6.4%), and HIV-1 infected (6.5%), and uninfected (10.4%) non-IDUs, and non-drug users (5.7%; P = 0.003). Higher resolved infection rates were also recorded in HIV-1 uninfected IDUs (11.2%) compared to HIV-1 infected IDUs (8.3%), and HIV-1 infected (7.2%), uninfected (6.3%) non-IDUs, and non-drug users (6.7%; P = 0.479), respectively. Only A1 genotype showing minimal diversity was detected among the study participants. CONCLUSION: HBV sero-markers and infection staging are valuable in diagnosis and genotyping of HBV infections. Among IDUs, higher HBsAg and HBcAb positivity in HIV-1 infected and higher HBsAb positivity in HIV-1 negative IDUs suggests frequent exposure. Additionally, HBV genotype A is the dominant circulating genotype in both high and low risk populations of Kenya.


Assuntos
Usuários de Drogas , Genótipo , Infecções por HIV/sangue , HIV-1 , Vírus da Hepatite B , Hepatite B/sangue , Adolescente , Adulto , Biomarcadores/sangue , Estudos Transversais , Usuários de Drogas/estatística & dados numéricos , Feminino , Anticorpos Anti-HIV/análise , Anticorpos Anti-HIV/sangue , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , HIV-1/genética , HIV-1/imunologia , Anticorpos Anti-Hepatite/análise , Anticorpos Anti-Hepatite/sangue , Hepatite B/complicações , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Humanos , Quênia/epidemiologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Testes Sorológicos , Abuso de Substâncias por Via Intravenosa/sangue , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologia , Adulto Jovem
5.
AIDS Res Ther ; 12: 27, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26279669

RESUMO

BACKGROUND: Although injection drug use drives antiretroviral drug resistance, the prevalence of protease inhibitor (PI) resistance among Kenyan IDUs remains undetermined. We, therefore, explored PI resistance mutations and their association with viral load and CD4+ T cell counts in HIV-1 infected IDUs (ART-naive, n = 32; and -experienced, n = 47) and non-drug users (ART-naive, n = 21; and -experienced, n = 32) naive for PI treatment from coastal Kenya. RESULTS: Only IDUs harboured major PI resistance mutations consisting of L90M, M46I and D30 N among 3 (6.4 %) ART-experienced and 1 (3.1 %) -naive individuals. Minor PI mutations including A71T, G48E, G48R, I13V, K20I, K20R, L10I, L10V, L33F, L63P, T74S, V11I, and V32L were detected among the ART-experienced (36.2 vs. 46.9 %) and -naive (43.8 vs. 66.7 %) IDUs and non-drug users, respectively. All the four IDUs possessing major mutations had high viral load while three presented with CD4+ T cell counts of <500 cells/ml. Among the ART-naive non-drug users, CD4+ T cell counts were significantly lower in carriers of minor mutations compared to non-carriers (P < 0.05). CONCLUSION: Transmitted drug resistance may occur in IDUs underscoring the need for genotyping resistance before initiating PI treatment.

6.
BMC Clin Pathol ; 14: 32, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25057262

RESUMO

BACKGROUND: Although the co-burden of injection drug use and HIV is increasing in Africa, little is known about the laboratory markers of injection drug use and anti-retroviral treatment (ART) in Kenyan injection drug users. This study, therefore, aimed at determining the clinical chemistry profiles and identifying the key laboratory markers of HIV infection during ART in injection heroin users (IHUs). METHODS: Clinical chemistry measurements were performed on serum samples collected from HIV-1 infected ART-experienced (n = 22), naive (n = 16) and HIV-1 negative (n = 23) IHUs, and healthy controls (n = 15) from Mombasa, coastal Kenya. RESULTS: HIV uninfected IHUs had lower alanine aminotransferase (ALT) levels (P = 0.023) as ART-exposed IHUs exhibited lower albumin (P = 0.014) and higher AST to platelet index (APRI) (P < 0.0001). All IHUs presented with lower aspartate aminotransferase to ALT values (P = 0.001) and higher C-reactive protein (CRP) levels (P = 0.002). ART-naive IHUs had higher globulin levels (P = 0.013) while ART-experienced and naive IHUs had higher albumin to total protein (P < 0.0001) and albumin to globulin (P < 0.0001) values. In addition, CD4+ T cells correlated with ALT (ρ = -0.522, P = 0.011) and CRP (rho, ρ = 0.529, P = 0.011) in HIV negative and ART-experienced IHUs, respectively. HIV-1 viral load correlated with albumin to globulin index in ART-experienced (ρ = -0.468, P = 0.037) and naive (ρ = -0.554, P = 0.040) IHUs; and with albumin to total protein index (ρ = -0.554, P = 0.040) and globulin (ρ = 0.570, P = 0.033) in ART-naive IHUs. CONCLUSION: Absolute ALT, albumin, globulin, and CRP measurements in combination with APRI, AST to ALT, albumin to total protein and albumin to globulin indices may be useful laboratory markers for screening IHUs for initiating and monitoring treatment.

7.
BMC Nutr ; 10(1): 55, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576036

RESUMO

INTRODUCTION: Despite documentation on injection drug use (IDU) in Kenya, the nutritional status of people who inject drugs (PWIDs) is under-explored. Elsewhere studies report under-nutrition among PWIDs which is attributed to food insecurity; competing priorities between drugs and food supply; chaotic lifestyle; reduced food intake; substance use induced malnutrition due to inflammation and comorbidities. METHODS: This was a cross-sectional study that sought to assess the nutritional status of PWIDs in Coastal Kenya. We recruited 752 participants of whom 371(49%) were on IDUs and 75 non-IDUs and 306 non-drug users using respondent driven sampling, traditional snowball, makeshift outreach and purposive sampling methods. RESULTS: More than one half of the participants (56%) had BMI classified as normal while 35% had BMI < 18.5. The proportion with BMI < 18.5 was higher among IDUs (46%) compared to the non-IDUs (33%) and non-drug users (23%) at P < 0.001. Using the mid upper arm circumference (MUAC), 17% were classified as underweight and the proportion was lowest (11%) among non- drugs users compared to 22% among IDUs (P < 0.001). However, the IDUs had lower proportion of overweight (8.1%) compared to 55% among the non- drug users. The proportion with low waist-for-hip ratio was highest among the IDUs (74%) while high waist-for-hip ratio was lowest in the same group of IDUs (11%) at P < 0.001. One half (50%), of the participants had no signs of anaemia, (47%) had mild/moderate anaemia while 21 (2.8%) had severe anaemia. However, IDUs were more likely to be overweight based on waist circumference as a parameter. The IDUs had the highest proportion (54%) of mild to moderate anaemia compared to non-IDUs (37%) and 40% non- drug users (P < 0.001). In the multivariable models, IDUs (aRRR 2.83 (95%CI 1.84‒4.35)) and non-IDUs (aRRR 1.42 (95%CI 1.07‒1.88)) compared to non- drug users were positively associated with BMI < 18.5. Being an IDU was positively associated with mild or moderate anaemia (aRRR 1.65 (95%CI 1.13‒2.41)) while non-IDUs were positively associated with severe anaemia (aRRR 1.69 (95%CI 1.16‒2.48)). CONCLUSION: A significant proportion of the participants were under-nourished with those injecting drugs bearing the heaviest brunt. Being an IDU was positively associated with the low BMI, MUAC, waist for hip ratio and mild or moderate anaemia but high waist circumference. People who inject drugs have high risk for under-nutrition and should be targeted with appropriate interventions.

8.
J Parasitol Res ; 2024: 1180217, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38348444

RESUMO

Background: Giardia duodenalis causes sporadic or epidemic infections in humans. The parasite comprises assemblages A-H with A and B subdivided further into AI-IV and BI-IV subassemblages. Attempts aimed at linking these genotypes with sources and gastrointestinal manifestations of the infection are largely unexplored in rural communities. Methods: In this cross-sectional study, G. duodenalis infection was genotyped and associated with sources, and gastrointestinal signs and symptoms of the disease among residents of Busia County, a rural setting in western Kenya. Demographic and clinical information were captured using standardized forms. Stool specimens were obtained from the patients and used for genotyping at glutamate dehydrogenase and triose-phosphate isomerase loci using the polymerase chain reaction and restriction fragment length polymorphism. Results: Assemblage B (63.6%) was the most prevalent G. duodenalis infection, while A (20.5%) and mixed A/B (15.9%) were also detected. Among the subassemblages, AI (5.7%), AII (8.0%), AIII (3.4), BIII (30.7%), and BIV (17.0%) were diagnosed including the mixed AII/BIII (15.9%), BIII/BIV (15.9%), AI/AIII (2.3%), and AI/AII (1.1%) infections. Binary logistic regression indicated associations for assemblage A with stomach upset, history of nitroimidazole treatment, and residing in a homestead with cattle and B with age < 18 years, history of eating outdoors, vomiting, steatorrhea, and residing in a homestead with cattle, goats, and poultry (p < 0.05 for all). Among the subassemblages, associations were found for AI with residing in a homestead having cattle and history of nitroimidazole treatment, BIII with residing in a homestead having cattle and poultry, and BIV with steatorrhea (p < 0.05 for all). Altogether, this study illustrates that G. duodenalis assemblage B and subassemblage BIII are the most predominant and are linked to age < 18 years, gastrointestinal manifestations, and living in a homestead with domestic ruminants and poultry. Conclusion: Targeted mass prophylactic treatment of domestic animals and utilization of gastrointestinal presentations, age < 18 years, and a history of nitroimidazole use are useful in the diagnosis and prevention of giardiasis among residents of rural communities.

9.
Ethiop J Health Sci ; 33(5): 735-742, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38784500

RESUMO

Background: Non-tuberculous mycobacteria (NTMs) are ubiquitous, free-living, environmental saprophytic microorganisms. NTMs belong to the genus Mycobacterium which includes Mycobacterium tuberculosis (MTB). NTMs have lately been a major cause of pulmonary disease (PD) in immuno-compromised individuals including HIV-1 patients. NTMs and MTB appear similar based on microscopy, radiology, and clinical symptoms; consequently, this may lead to misdiagnosis. This study sought to establish the prevalence of NTM pulmonary disease in HIV-1 patients presumed to have pulmonary tuberculosis. Methods: A cross-sectional analytical laboratory study design was used targeting 617 adult HIV-1 infected patients presenting with presumptive pulmonary TB at Bungoma County Hospital Comprehensive Care Clinic in Western Kenya between July 2021 to June 2022. Results: A total of 75 (12.2%, 4.6 -9.8 CI) of the participants presented with presumptive MTB and had TB-like symptoms while 542 (87.8%, 12.5 -30.7 CI) were negative. Additionally, 56 (9.1%) were infected with NTMs. HIV-positive participants had a significantly higher prevalence of NTMs 62 (11.8%, 5.6 -9.2 CI) compared to 2 (2.1%, 0.4 -1.8 CI). In HIV + study participants P<0.0001. M. avium was the most prevalent NTM, 25(33.3%), followed by M. fortuitum 20 (26.7%). A significant number of the isolates were M. tuberculosis 10 (13.3%) as well as M. kansasii 8 (10.7%). Conclusion: There seems to be a high prevalence of NTMPD in HIV-1 patients which is assumed to be pulmonary TB. Differential diagnosis of the mycobacterium species is necessary to help improve disease management and outcomes in this group of patients.


Assuntos
Infecções por HIV , HIV-1 , Infecções por Mycobacterium não Tuberculosas , Micobactérias não Tuberculosas , Tuberculose Pulmonar , Humanos , Quênia/epidemiologia , Masculino , Adulto , Feminino , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Infecções por Mycobacterium não Tuberculosas/microbiologia , Estudos Transversais , Prevalência , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/microbiologia , Infecções por HIV/epidemiologia , Infecções por HIV/complicações , Pessoa de Meia-Idade , Micobactérias não Tuberculosas/isolamento & purificação , Adulto Jovem
10.
Hum Genet ; 131(8): 1375-91, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22570109

RESUMO

Severe malarial anemia (SMA) is a leading cause of pediatric morbidity and mortality in holoendemic Plasmodium falciparum transmission areas. Although dysregulation in cytokine production is an important etiology of SMA, the role of IFN-α in SMA has not been reported. As such, we investigated the relationship between IFN-α promoter polymorphisms [i.e., IFNA2 (A-173T) and IFNA8 (T-884A)], SMA, and functional changes in IFN-α production in children (n = 663; <36 months) residing in a holoendemic P. falciparum transmission region of Kenya. Children with SMA had lower circulating IFN-α than malaria-infected children without severe anemia (P = 0.025). Multivariate logistic regression analyses revealed that heterozygosity at -884 (TA) was associated with an increased risk of SMA [OR 2.80 (95 % CI 1.22-6.43); P = 0.015] and reduced IFN-α relative to wild type (TT; P = 0.038). Additional analyses demonstrated that carriage of the -173T/-884A (TA) haplotype was associated with increased susceptibility to SMA [OR 3.98 (95 % CI 1.17-13.52); P = 0.026] and lower IFN-α (P = 0.031). Follow-up of these children for 36 months revealed that carriers of TA haplotype had greater all-cause mortality than non-carriers (P < 0.001). Generation of reporter constructs showed that the IFNA8 wild-type -884TT exhibited higher levels of luciferase expression than the variant alleles (P < 0.001). Analyses of malaria-associated inflammatory mediators demonstrated that carriers of TA haplotype had altered production of IL-1ß, MIG, and IL-13 compared to non-carriers (P < 0.050). Thus, variation at IFNA2 -173 and IFNA8 -884 conditions reduced IFN-α production, and increased susceptibility to SMA and mortality.


Assuntos
Anemia/genética , Causas de Morte , Predisposição Genética para Doença , Haplótipos , Interferon-alfa/biossíntese , Malária/etiologia , Anemia/complicações , Sequência de Bases , Linhagem Celular , Primers do DNA , Feminino , Humanos , Lactente , Interferon-alfa/genética , Estudos Longitudinais , Masculino , Reação em Cadeia da Polimerase
11.
Hum Genet ; 131(2): 289-99, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21818580

RESUMO

Development of protective immunity against Plasmodium falciparum is partially mediated through binding of malaria-specific IgG to Fc gamma (γ) receptors. Variations in human FcγRIIA-H/R-131 and FcγRIIIB-NA1/NA2 affect differential binding of IgG sub-classes. Since variability in FcγR may play an important role in severe malarial anemia (SMA) pathogenesis by mediating phagocytosis of red blood cells and triggering cytokine production, the relationship between FcγRIIA-H/R131 and FcγRIIIB-NA1/NA2 haplotypes and susceptibility to SMA (Hb < 6.0 g/dL) was investigated in Kenyan children (n = 528) with acute malaria residing in a holoendemic P. falciparum transmission region. In addition, the association between carriage of the haplotypes and repeated episodes of SMA and all-cause mortality were investigated over a 3-year follow-up period. Since variability in FcγR can alter interferon (IFN)-γ production, a mediator of innate and adaptive immune responses, functional associations between the haplotypes and IFN-γ were also explored. During acute malaria, children with SMA had elevated peripheral IFN-γ levels (P = 0.006). Although multivariate logistic regression analyses (controlling for covariates) revealed no associations between the FcγR haplotypes and susceptibility to SMA during acute infection, the FcγRIIA-131H/FcγRIIIB-NA1 haplotype was associated with decreased peripheral IFN-γ (P = 0.046). Longitudinal analyses showed that carriage of the FcγRIIA-131H/FcγRIIIB-NA1 haplotype was associated with reduced risk of SMA (RR 0.65, 95% CI 0.46-0.90; P = 0.012) and all-cause mortality (P = 0.002). In contrast, carriers of the FcγRIIA-131H/FcγRIIIB-NA2 haplotype had increased susceptibility to SMA (RR 1.47, 95% CI 1.06-2.04; P = 0.020). Results here demonstrate that variation in the FcγR gene alters susceptibility to repeated episodes of SMA and mortality, as well as functional changes in IFN-γ production.


Assuntos
Anemia/complicações , Anemia/genética , Interferon gama/metabolismo , Malária/genética , Malária/mortalidade , Receptores de IgG/genética , Receptores de IgG/metabolismo , Pré-Escolar , Proteínas Ligadas por GPI/metabolismo , Predisposição Genética para Doença , Haplótipos , Humanos , Lactente , Recém-Nascido , Quênia/epidemiologia , Estudos Longitudinais , Recidiva
12.
Am J Hematol ; 87(7): 652-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22570198

RESUMO

Anemia is the primary hematological manifestation of both Plasmodium falciparum malaria and HIV-1 in pediatric populations in sub-Saharan Africa. We have previously shown that HIV-1 positive and exposed children have greater risk of developing severe anemia (hemoglobin, Hb <6.0 g dL⁻¹) during acute malaria. However, enhanced severity of anemia was unrelated to either erythropoietic suppression or parasite-driven red blood cell hemolysis. To further explore mechanisms of anemia, circulating inflammatory mediators (IMs) were determined using a 25-plex bead array in P. falciparum-infected (Pf[+]) children (3-36 month, n = 194) stratified into three groups: HIV-1 negative (HIV-1[-]/Pf[+]); HIV-1 exposed (HIV-1[exp]/Pf[+]); and HIV-1 infected (HIV-1[+]/Pf[+]). IL-12, MIG/CXCL9, eotaxin/CCL11, and GM-CSF differed significantly and progressively increased across the groups (HIV-1[-]→HIV-1[exp]→HIV-1[+]). To further explore the relationship between the inflammatory milieu (i.e., cytokines, chemokines, and growth factors) and HIV-1 status, the large panel of IMs was reduced into discrete groups by principal component factor analysis. Of the six principal components that emerged, three components were significantly higher in the HIV-1 [+]/pf[+] and HIV[exp]/Pf[+] groups, demonstrating that inflammatory profiles differ according to HIV-1 status. Additional analyses exploring the relationship between the components and anemia revealed significant positive correlations between Hb and Component 3 (IL-1Ra, IL-7, IL-17, IFN-α, IFN-γ, MIG/CXCL9) in the HIV-1[-]/Pf[+] group, and Component 4 (IL-4, IL-5, IL-12, Eotaxin/CCL11) in HIV-1[+]/Pf[+] children. Further analyses of the HIV-1[+]/Pf[+] group revealed that IL-12 had the strongest association with anemia. Results presented here demonstrate that there are unique relationships between the inflammatory environment and anemia in HIV-1 positive and exposed children with malaria.


Assuntos
Anemia/imunologia , Citocinas/sangue , Soropositividade para HIV/imunologia , HIV-1/imunologia , Malária Falciparum/imunologia , Plasmodium falciparum/imunologia , Anemia/sangue , Anemia/etiologia , Anemia/fisiopatologia , Quimiocina CCL11/sangue , Quimiocina CXCL9/sangue , Pré-Escolar , Estudos de Coortes , Coinfecção/imunologia , Coinfecção/parasitologia , Coinfecção/fisiopatologia , Coinfecção/virologia , Estudos Transversais , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/sangue , Infecções por HIV/complicações , Infecções por HIV/imunologia , Infecções por HIV/fisiopatologia , Infecções por HIV/virologia , Soropositividade para HIV/complicações , Soropositividade para HIV/fisiopatologia , Soropositividade para HIV/virologia , HIV-1/isolamento & purificação , Humanos , Lactente , Interleucina-12/sangue , Quênia , Malária Falciparum/complicações , Malária Falciparum/parasitologia , Malária Falciparum/fisiopatologia , Masculino , Plasmodium falciparum/isolamento & purificação , Índice de Gravidade de Doença
13.
Am J Hematol ; 87(8): 782-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22730036

RESUMO

In holoendemic Plasmodium falciparum transmission areas, severe malaria primarily occurs in children aged <48 months and manifests as severe malarial anemia [SMA; hemoglobin (Hb) < 6.0 g/dL]. Induction of high levels of prostaglandin-E(2) (PGE(2)) through inducible cyclooxygenase-2 (COX-2) is an important host-defense mechanism against invading pathogens. We have previously shown that COX-2-derived PGE(2) levels are reduced in children residing in hyperendemic transmission regions with cerebral malaria and in those with mixed sequelae of anemia and hyperparasitemia. Our in vitro studies further demonstrated that reduced PGE(2) was due to downregulation of COX-2 gene products following phagocytosis of malarial pigment (hemozoin, PfHz). However, as COX-2-PGE(2) pathways and the impact of naturally acquired PfHz on erythropoietic responses have not been determined in children with SMA, plasma and urinary bicyclo-PGE(2)/creatinine and leukocytic COX-2 transcripts were determined in parasitized children (<36 months) stratified into SMA (n = 36) and non-SMA (Hb ≥ 6.0 g/dL; n = 38). Children with SMA had significantly reduced plasma (P = 0.001) and urinary (P < 0.001) bicyclo-PGE(2)/creatinine and COX-2 transcripts (P = 0.007). There was a significant positive association between Hb and both plasma (r = 0.363, P = 0.002) and urinary (r = 0.500, P = 0.001)] bicyclo-PGE(2)/creatinine. Furthermore, decreased systemic bicyclo-PGE(2)/creatinine was associated with inefficient erythropoiesis (i.e., reticulocyte production index; RPI < 2.0, P = 0.026). Additional analyses demonstrated that plasma (P = 0.031) and urinary (P = 0.070) bicyclo-PGE(2)/creatinine and COX-2 transcripts (P = 0.026) progressively declined with increasing concentrations of naturally acquired PfHz by monocytes. Results presented here support a model in which reduced COX-2-derived PGE(2), driven in part by naturally acquired PfHz by monocytes, promotes decreased erythropoietic responses in children with SMA.


Assuntos
Anemia , Ciclo-Oxigenase 2/biossíntese , Dinoprostona , Eritropoese , Regulação Enzimológica da Expressão Gênica , Hemeproteínas/metabolismo , Malária Falciparum , Anemia/sangue , Anemia/parasitologia , Anemia/urina , Pré-Escolar , Creatinina/sangue , Creatinina/urina , Dinoprostona/sangue , Dinoprostona/urina , Feminino , Humanos , Lactente , Malária Falciparum/sangue , Malária Falciparum/urina , Masculino , Monócitos/metabolismo , Monócitos/parasitologia , Parasitemia , Fagocitose , Índice de Gravidade de Doença
14.
BMC Infect Dis ; 12: 143, 2012 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-22726955

RESUMO

BACKGROUND: Over the years, reports implicate improper anti-malarial use as a major contributor of morbidity and mortality amongst millions of residents in malaria endemic areas, Kenya included. However, there are limited reports on improper use of Artemisinin-based Combination Therapy (ACT) which is a first-line drug in the treatment of malaria in Kenya. Knowing this is important for ensured sustainable cure rates and also protection against the emergence of resistant malarial parasites. We therefore investigated ACT adherence level, factors associated with non-adherence and accessibility in households (n = 297) in rural location of Southeast Alego location in Siaya County in western Kenya. METHODS: ACT Adherence level was assessed with reference to the duration of treatment and number of tablets taken. Using systematic random sampling technique, a questionnaire was administered to a particular household member who had the most recent malaria episode (<2 weeks) and used ACT for cure. Parents/caretakers provided information for children aged <13 years. Key Informant Interviews (KIIs) were also conducted with healthcare providers and private dispensing chemist operators. RESULTS: Adherence to ACT prescription remained low at 42.1% and 57.9% among individuals above 13 and less than 13 years, respectively. Stratification by demographic and socio-economic characteristics in relation to ACT adherence revealed that age (P = 0.011), education level (P < 0.01), ability to read (P < 0.01) and household (HH) monthly income (P = 0.002) significantly affected the level of ACT adherence. Consistently, logistic regression model demonstrated that low age (OR, 0.571, 95% CI, 0.360-0.905; P = 0.017), higher education level (OR, 0.074; 95% CI 0.017-0.322; P < 0.01), ability to read (OR, 0.285, 95% CI, 0.167-0.486; P < 0.01) and higher income (Ksh. > 9000; OR, 0.340; 95% CI, 0.167-0.694; P = 0.003) were associated with ACT adherence. In addition, about 52.9% of the respondents reported that ACT was not always available at the source and that drug availability (P = 0.020) and distance to drug source (P < 0.01) significantly affected accessibility. CONCLUSIONS: This study demonstrates that more than half of those who get ACT prescription do not take recommended dose and that accessibility is of concern. The findings of this study suggest a potential need to improve accessibility and also initiate programmatic interventions to encourage patient-centred care.


Assuntos
Antimaláricos/administração & dosagem , Artemisininas/administração & dosagem , Malária/tratamento farmacológico , Adesão à Medicação/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos Transversais , Quimioterapia Combinada/métodos , Feminino , Humanos , Lactente , Recém-Nascido , Quênia , Masculino , Pessoa de Meia-Idade , População Rural , Inquéritos e Questionários , Adulto Jovem
15.
Afr Health Sci ; 22(1): 431-442, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36032475

RESUMO

Introduction: Illicit substance use and HIV infection cause haematological derangements. Anaemia characterized by a reduction in the quality and quantity erythrocytes is the most common disorder in both HIV-positive persons and illicit substance users. Objective: To describe anaemia burden, types, and its association with HIV in injectable substance users in Mombasa, Kenya. Methods: This descriptive case-control study evaluated red cell indices and morphology in 494 adults. The primary outcome was anaemia. The association of anaemia with HIV in injection substance users was determined using the chi-square test. Results: The participants included 275 injection substance users (ISU), (HIV-positive, n=62 and HIV-negative, n=213); and 219 non-injection substance users (nonISU), (HIV-positive, n=33 and HIV-negative, n=186). Overall, 49% were anaemic with anaemia burden significantly differing across the groups, X2(3, N=494) =12.1, p=0.0070. Anaemia burden was higher in HIV-positive ISU compared to HIV-negative ISU (odds ratio (OR) = 1.59, 95% confidence interval (CI): 0.85, 2.96); and HIV-positive nonISU compared to HIV-negative nonISU (OR = 0.37, 95% confidence interval (CI): 0.17, 0.79). Most of the anaemia was dimorphic in both HIV-positive (ISU, 67% and nonISU, 52%) and HIV-negative (ISU, 43% and nonISU, 55%) participants. Conclusion: Infection with HIV is associated with increased risk of anaemia in injectable and non-injectable substance users. Majority of the anaemia was dimorphic suggestive of multiple aetiologies. Establishing the related aetiologies is essential for the effective treatment of anaemia. The accurate evaluation of thin blood films remains an essential tool in diagnosing an array of haematologic disorders and as a reference for further tests and patient management.


Assuntos
Anemia , Infecções por HIV , Transtornos Relacionados ao Uso de Substâncias , Adulto , Estudos de Casos e Controles , Humanos , Quênia
16.
Infect Immun ; 79(12): 4923-32, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21969001

RESUMO

Severe malarial anemia (SMA) is a leading cause of morbidity and mortality in children residing in regions where Plasmodium falciparum transmission is holoendemic. Although largely unexplored in children with SMA, interleukin-18 (IL-18) is important for regulating innate and acquired immunity in inflammatory and infectious diseases. As such, we selected two functional single-nucleotide polymorphisms (SNPs) in the IL-18 promoter (-137G→C [rs187238] and -607C→A [rs1946518]) whose haplotypes encompass significant genetic variation due to the presence of strong linkage disequilibrium among these variants. The relationship between the genotypes/haplotypes, SMA (hemoglobin [Hb], <5.0 g/dl], and longitudinal clinical outcomes were then investigated in Kenyan children (n = 719). Multivariate logistic regression analyses controlling for age, gender, sickle cell trait, glucose-6-phosphate dehydrogenase (G6PD) deficiency, HIV-1, and bacteremia revealed that carriage of the -607AA genotype was associated with protection against SMA (odds ratio [OR] = 0.440 [95% confidence interval {CI} = 0.21 to 0.90], P = 0.031) in children with acute infection. In contrast, carriers of the -137G/-607C (GC) haplotype had increased susceptibility to SMA (OR = 2.050 [95% CI = 1.04 to 4.05], P = 0.039). Measurement of IL-18 gene expression in peripheral blood leukocytes demonstrated that elevated IL-18 transcripts were associated with reduced hemoglobin concentrations (ρ = -0.293, P = 0.010) and that carriers of the "susceptible" GC haplotype had elevated IL-18 transcripts (P = 0.026). Longitudinal investigation of clinical outcomes over a 3-year follow-up period revealed that carriers of the rare CC haplotype (∼1% frequency) had 5.76 times higher mortality than noncarriers (P = 0.001). Results presented here demonstrate that IL-18 promoter haplotypes that condition elevated IL-18 gene products during acute infection are associated with increased risk of SMA. Furthermore, carriage of the rare CC haplotype significantly increases the risk of childhood mortality.


Assuntos
Anemia/etiologia , Haplótipos/genética , Mortalidade Infantil , Interleucina-18/genética , Malária Falciparum/complicações , Regiões Promotoras Genéticas/genética , Feminino , Regulação da Expressão Gênica/fisiologia , Testes Genéticos , Variação Genética , Humanos , Lactente , Quênia/epidemiologia , Desequilíbrio de Ligação , Malária Falciparum/epidemiologia , Malária Falciparum/mortalidade , Masculino , Razão de Chances , Fatores de Risco
17.
BMC Genet ; 12: 69, 2011 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-21819616

RESUMO

BACKGROUND: Plasmodium falciparum malaria remains a leading cause of morbidity and mortality among African children. Innate immunity provides the first line of defence against P. falciparum infections, particularly in young children that lack naturally-acquired malarial immunity, such as the population examined here. Consistent with the fact that elevated interleukin (IL)-12 is an important component of the innate immune response that provides protective immunity against malaria, we have previously shown that suppression of IL-12 in African children is associated with the development of severe malarial anaemia (SMA). Since the role of IL12B variants in conditioning susceptibility to SMA remains largely unexplored, the association between a single nucleotide polymorphism (1188A→C, rs3212227), SMA (Hb<6.0 g/dL), circulating IL-12p40/p70 levels, and longitudinal clinical outcomes in Kenyan children (n = 756) residing in a holoendemic falciparum malaria transmission area were investigated. RESULTS: Multivariate logistic regression analysis in children with acute malaria (n = 544) demonstrated that carriers of the C allele had increased susceptibility to SMA (CC: OR, 1.674; 95% CI, 1.006-2.673; P = 0.047, and AC: OR, 1.410; 95% CI, 0.953-2.087; P = 0.086) relative to wild type (AA). Although children with SMA had lower IL-12p40/p70 levels than the non-SMA group (P = 0.037), levels did not differ significantly according to genotype. Longitudinal analyses in the entire cohort (n = 756) failed to show any significant relationships between rs3212227 genotypes and either susceptibility to SMA or all-cause mortality throughout the three year follow-up. CONCLUSION: The rs3212227 is a marker of susceptibility to SMA in children with acute disease, but does not appear to mediate functional changes in IL-12 production or longitudinal outcomes during the acquisition of naturally-acquired malarial immunity.


Assuntos
Anemia/genética , Subunidade p40 da Interleucina-12/genética , Malária Falciparum/complicações , Malária Falciparum/genética , Polimorfismo de Nucleotídeo Único , Regiões 3' não Traduzidas , Anemia/complicações , Anemia/mortalidade , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Lactente , Quênia , Estudos Longitudinais , Masculino
18.
Int J Health Sci (Qassim) ; 15(3): 3-11, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234630

RESUMO

OBJECTIVE: The coburden of human immunodeficiency virus (HIV) and injection substance use is high especially in coastal urban and peri-urban regions of sub-Saharan Africa. Although antiretroviral treatment (ART) has improved disease prognosis in HIV-1-infected patients, injection substance use is detrimental to these individuals. HIV-1 and injection substances use have been associated with a marked reduction in serum albumin levels. This is attributable to at least, in part, injection substance use, ARVs, HIV-1 infection, as well as host genetics. The albumin gene expression is modulated through several mechanisms including intronic consensus elements. Therefore, this study examined ALB gene rs1445776009 intronic polymorphism and its association with disease outcomes. METHODS: This cross-sectional study was conducted at Bomu Hospital, Mombasa County, Kenya. A total of 155 injection substance users (ISUs) were recruited comprising 93 ART experienced and 62 ART naive. Variant rs1445776009 was amplified through polymerase chain reaction and genotyped through restriction fragment length polymorphism. RESULTS: Carriers of the mutant and GG had significantly lower body mass index (P = 0.033), serum albumin (P = 0.002), CD4+ T cells (P = 0.031), and higher HIV-1 RNA copies (P = 0.018) relative to wild type, CC and heterozygous, CG; in ART-experienced ISUs. In addition, mutant GG carriers were at higher odds of presenting with hypoalbuminemia (OR, 1.933; 95% CI, 1.524-4.664; P = 0.033), underweight (OR, 2.412; 95% CI, 1.124-5.782; P = 0.026), immunosuppression (OR, 3.036; 95% CI, 1.957-9.633; P = 0.021), and high-density HIV viremia (OR, 1.836; 95% CI, 1.134-6.298; P = 0.016). CONCLUSION: This study's findings appear to suggest that loci rs1445776009 of the ALB gene could be modulating serum albumin levels and disease outcomes in HIV-1 ART-experienced ISUs.

19.
Afr Health Sci ; 21(4): 1584-1592, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35283948

RESUMO

Background: Cytokines play an important role in signaling the immune system to build an adequate immune response against HIV. HIV distorts the balance between pro and anti-inflammatory cytokines causing viral replication. Highly active antiretroviral treatment (HAART) acts by trying to restore pro and anti-inflammatory cytokine balance. It is not clear how HAART non-adherence influences circulating cytokine levels. This study therefore determined cytokine levels in HAART non-adherent individuals. Methods: This cross-sectional study recruited 163 participants (51 controls, 23 HIV-1+ HAART naive, 28 HAART-adherent 6 months, 19 HAART-adherent 12 months and 42 HAART non-adherent). Cytokines were analyzed by ELISA while CD4 T cells determined in 3.0 µl of whole blood using BD FACSCaliburTM and viral load in 0.2ml plasma sample using Abbott Molecular m2000sp sample preparation and m2000rt real-time amplification and detection systems (Abbott Molecular Inc., Illinois, USA) according to the manufacturer's methods. Results: IL-4, IL-6, IL-10, TNF-α and TGF-ß were significantly elevated in HIV-1 HAART non-adherent compared with HIV-1 HAART adherent and healthy controls P<0.01. IFN- γ was significantly decreased in HIV-1 HAART non-adherent compared with HIV-1 HAART adherent and healthy controls P<0.01. TNF-α and TGF-ß were significantly reduced in HIV-1 HAART adherent patients at 12 months compared to those at 6 months P<0.01. IL-4 and IL-10 correlated positively with viral load. IL-4, IL-6, IL-10, TNF-α and TGF- ß associated inversely with CD4 T cell counts and body mass index (BMI). Conclusion: This study established that HAART adherence is immunologically beneficial to the pro and anti-inflammatory cytokine balance milieu while non-adherence appears to cause alterations in pro and anti-inflammatory cytokines warping the balance in this dichotomy.


Assuntos
Infecções por HIV , HIV-1 , Estudos Transversais , Citocinas , Humanos , Quênia/epidemiologia
20.
Infect Immun ; 78(1): 453-60, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19884328

RESUMO

Plasmodium falciparum malaria is a leading global cause of infectious disease burden. In areas in which P. falciparum transmission is holoendemic, such as western Kenya, severe malarial anemia (SMA) results in high rates of pediatric morbidity and mortality. Although the pathophysiological basis of SMA is multifactorial, we recently discovered that suppression of unexplored hematopoietic growth factors that promote erythroid and myeloid colony development, such as stem cell growth factor (SCGF) (C-type lectin domain family member 11A [CLEC11A]), was associated with enhanced development of SMA and reduced erythropoietic responses. To extend these investigations, the relationships between a novel SCGF promoter variant (-539C/T, rs7246355), SMA (hemoglobin [Hb] < 6.0 g/dl), and reduced erythropoietic responses (reticulocyte production index [RPI], <2.0) were investigated with Kenyan children (n = 486) with falciparum malaria from western Kenya. Circulating SCGF was positively correlated with hemoglobin levels (r = 0.251; P = 0.022) and the reticulocyte production index (RPI) (r = 0.268; P = 0.025). Children with SMA also had lower SCGF levels than those in the non-SMA group (P = 0.005). Multivariate logistic regression analyses controlling for covariates demonstrated that individuals with the homologous T allele were protected against SMA (odds ratio, 0.57; 95% confidence interval [95% CI] 0.34 to 0.94; P = 0.027) relative to CC (wild-type) carriers. Carriers of the TT genotype also had higher SCGF levels in circulation (P = 0.018) and in peripheral blood mononuclear cell culture supernatants (P = 0.041), as well as an elevated RPI (P = 0.005) relative to individuals with the CC genotype. The results presented here demonstrate that homozygous T at -539 in the SCGF promoter is associated with elevated SCGF production, enhanced erythropoiesis, and protection against the development of SMA in children with falciparum malaria.


Assuntos
Anemia/etiologia , Anemia/genética , Regulação da Expressão Gênica/fisiologia , Fatores de Crescimento de Células Hematopoéticas/genética , Lectinas Tipo C/genética , Malária Falciparum/complicações , Pré-Escolar , Feminino , Variação Genética , Genótipo , Humanos , Lactente , Masculino , Regiões Promotoras Genéticas
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