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1.
BMC Microbiol ; 23(1): 189, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37460950

RESUMO

BACKGROUND: Podoconiosis, a non-infectious disease originating from long-term exposure of bare feet to irritant red clay soil is a lifelong, disabling disease with no specific diagnostic tool, classified into 5 stages based on the severity of leg swelling (lymphoedema). Secondary bacterial infections have been suggested to cause acute dermatolymphangioadenitis (ADLA) attacks and drive disease progression. Although the North West Region of Cameroon has a proven history of podoconiosis endemicity, the bacterial composition of lymphoedema due to this condition has not been studied. Thus, this study investigated the leg bacterial diversity of patients who suffered from the lymphoedema and their susceptibility pattern to selected antibiotics. METHODS: A cross-sectional study was carried out in which podoconiosis affected and non-lymphoedema individuals living in the same community were purposively selected. Samples were collected by swabbing the skin between the toes and around the anklebone, then cultured and sub-cultured on nutrient agar to obtain pure isolates. The cultured isolates were then morphologically and biochemically classified using microscopy and analytic profile index test kits, respectively. The disk diffusion technique was used to determine antibiotic susceptibility. RESULTS: Thirty-three participants were recruited, and 249 bacterial isolates were characterized into 29 genera, 60 species; with 30 (50%) being gram positive rods, 19 (31.7%) gram positive cocci, and 11 (18.3%) gram negative rods. Thirteen gram positive rods, fifteen gram positive cocci, and eight gram negative rods of bacterial species were found only in podoconiosis individuals among which Cellulomonas spp / Microbacterium spp. (2.8%), Staphylococcus lentus (3.3%), and Burkholderia cepacia (4.0%) dominated. 90% (90%) of the bacterial isolates were sensitive to doxycycline, whereas ampicillin had a high level of intermediate resistance, and penicillin G had the greatest resistant profile. CONCLUSION: Our findings show that 94 (37.8%) out of 249 described bacterial isolates were exclusively found in the legs of podoconiosis individuals, and their susceptibility pattern to antibiotics was similar to that of others.


Assuntos
Elefantíase , Linfedema , Humanos , Elefantíase/diagnóstico , Elefantíase/etiologia , Camarões , Estudos Transversais , Linfedema/complicações , Antibacterianos/farmacologia , Bactérias Gram-Negativas , Testes de Sensibilidade Microbiana
2.
BMC Health Serv Res ; 22(1): 924, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35854308

RESUMO

BACKGROUND: Globally, there is recognition of the value of using mobile phones among health providers in improving health systems performance. However, in many Low- and Middle-income countries where there is shortage of health providers, Community Health Workers have assumed some responsibilities especially relating to identifying and reporting on health problems within their communities. Despite the known benefits of using mobile phone technology to deliver health services, there is limited information on the extent to which Community Health Workers are able to effectively use the technology in data collection and reporting. The aim of this study was to determine the feasibility of utilizing phone-based text messages on Lymphatic Filariasis morbidity surveillance by Community Health Workers. METHODS: This was a cross sectional study whose data was collected through key informant interviews and focused group discussions among community health workers, health providers and staff of neglected tropical diseases control program. Collected transcripts were analysed through Thematic content analysis as it allowed for the identification of data codes through inductive reasoning. RESULTS: The use of mobile phone-based text messages in data collection and reporting lymphatic filariasis morbidity cases by Community Health Workers was perceived by study participants to be a relevant tool and feasible due to the ease of use of the technology. The tool was reported by end-users to significantly increase their performance and efficiency was gained in terms of reduced paper work, increased the number of patients accessing health care services and the ability to report in real-time. All respondents were confident that Community Health Workers were the right persons to interact with communities in tracking and reporting morbidity cases using mobile technology. CONCLUSION: Mobile phone-based text messages have proven to be effective in routine workflows such as, data collection and reporting on Lymphatic Filariasis morbidity cases, patient to provider communication, decision making and supportive supervision. Mobile phones have also improved efficiency and general performance of end users in terms of increased number of cases identified and efficiency gained in terms of reduced paper work and the ability to collect and report in real-time.


Assuntos
Telefone Celular , Filariose Linfática , Envio de Mensagens de Texto , Agentes Comunitários de Saúde , Estudos Transversais , Filariose Linfática/epidemiologia , Humanos , Morbidade , Doenças Negligenciadas , Tanzânia/epidemiologia
3.
Parasitol Res ; 121(4): 1199-1206, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35006317

RESUMO

The filarial nematode Onchocerca volvulus causes onchocerciasis (river blindness), a neglected tropical disease affecting 21 million people, mostly in Sub-Saharan Africa. Targeting the endosymbiont Wolbachia with antibiotics leads to permanent sterilization and killing of adult worms. The gold standard to assess Wolbachia depletion is the histological examination of adult worms in nodules beginning at 6 months post-treatment. However, nodules can only be used once, limiting the time points to monitor Wolbachia depletion. A diagnostic to longitudinally monitor Wolbachia depletion from microfilariae (MF) at more frequent intervals < 6 months post-treatment would accelerate clinical trials of antiwolbachials. We developed a TaqMan qPCR amplifying the single-copy gene wOvftsZ to quantify Wolbachia from as few as one MF that had migrated from skin biopsies and compared quantification using circular and linearized plasmids or synthetic dsDNA (gBlock®). qPCR for MF from the rodent nematode Litomosoides sigmodontis was used to support the reproducibility and validate the principle. The qPCR using as few as 2 MF from O. volvulus and L. sigmodontis reproducibly quantified Wolbachia. Use of a linearized plasmid standard or synthesized dsDNA resulted in numbers of Wolbachia/MF congruent with biologically plausible estimates in O. volvulus and L. sigmodontis MF. The qPCR assay yielded a median of 48.8 (range 1.5-280.5) Wolbachia/O. volvulus MF. The qPCR is a sensitive tool for quantifying Wolbachia in a few MF from skin biopsies and allows for establishing the qPCR as a surrogate parameter for monitoring Wolbachia depletion in adult worms of new antiwolbachial candidates.


Assuntos
Filarioidea , Onchocerca volvulus , Wolbachia , Animais , Humanos , Microfilárias , Onchocerca , Onchocerca volvulus/genética , Reprodutibilidade dos Testes , Wolbachia/efeitos dos fármacos , Wolbachia/genética
4.
Pacing Clin Electrophysiol ; 44(6): 1027-1032, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33974720

RESUMO

BACKGROUND: Very little is known about the long-term prevalence of severe venous obstruction and occlusion in patients with transvenous implantable cardioverter-defibrillator leads. The objective of the current investigation was to elucidate the incidence and prevalence and to identify predisposing conditions in an ICD cohort over a long follow-up period. METHODS: Based on a prospective database, we analyzed consecutive patients who received an ICD implantation in our hospital between 06/1988 and 2009 as well as all corresponding follow-up data until 02/2018. Cavographies were used for analysis, and all patients with at least one device replacement and one follow-up cavography were included. RESULTS: Over a mean follow-up period of 94 ± 50 months, severe venous obstruction was found in 147 (33%) of 448 patients. Kaplan-Meier analysis shows a severe obstruction or occlusion in 50% of patients after a period of 14.3 years. The total number of leads (p < .001, HR 2.01, CI 2.000-2.022), an advanced age (p = .004, HR 1.023 per year, CI 1.022-1.024) and the presence of dilated cardiomyopathy (p = .035, HR 1.49, CI 1.47-1.51) were predictive of venous obstruction whereas the presence of anticoagulation was not. CONCLUSION: Severe obstruction of the access veins after ICD implantation occurs frequently and its prevalence shows a nearly linear increase over long-time follow-up. Multiple leads, an advanced age and DCM as underlying disease are associated with an increased risk of venous obstruction while the role of anticoagulation to prevent venous obstruction in ICD patients is unclear.


Assuntos
Desfibriladores Implantáveis/efeitos adversos , Doenças Vasculares Periféricas/etiologia , Extremidade Superior/irrigação sanguínea , Constrição Patológica/epidemiologia , Constrição Patológica/etiologia , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Doenças Vasculares Periféricas/epidemiologia , Estudos Prospectivos
5.
Clin Infect Dis ; 71(4): 933-943, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31536624

RESUMO

BACKGROUND: Improved treatment for onchocerciasis is needed to accelerate onchocerciasis elimination in Africa. Aiming to better exploit registered drugs, this study was undertaken to determine whether annual or semiannual treatment with ivermectin (IVM; 200 µg/kg) plus albendazole (ALB; 800 mg single dose) is superior to IVM alone. METHODS: This trial was performed in Ghana and included 272 participants with microfilariae (MF), who were randomly assigned to 4 treatment arms: (1) IVM annually at 0, 12, and 24 months; (2) IVM semiannually at 0, 6, 12, 18, and 24 months; (3) IVM+ALB annually; or (4) IVM+ALB semiannually. Microfiladermia was determined pretreatment and at 6, 18, and 36 months. The primary outcome was the proportion of fertile and viable female worms in onchocercomata excised at 36 months. RESULTS: Posttreatment nodule histology showed that 15/135 (11.1%), 22/155 (14.2%), 35/154 (22.7%), and 20/125 (16.0%) living female worms had normal embryogenesis in the IVM annual, IVM semiannual, IVM+ALB annual, and IVM+ALB semiannual groups, respectively (P = .1229). Proportions of dead worms also did not differ between the 4 groups (P = .9198). Proportions of patients without MF at 36 months (1 year after the last treatment) were 35/56 (63%) after annual IVM, 42/59 (71%) after semiannual IVM, 39/64 (61%) after annual IVM+ALB, and 43/53 (81%) after semiannual IVM+ALB. CONCLUSIONS: The combination treatment of IVM plus ALB was no better than IVM alone for sterilizing, killing adult worms, or achieving sustained MF clearance. However, semiannual treatment was superior to annual treatment for achieving sustained clearance of Onchocerca volvulus MF from the skin (P = .024). CLINICAL TRIALS REGISTRATION: ISRCTN50035143.


Assuntos
Onchocerca volvulus , Oncocercose , Albendazol/uso terapêutico , Animais , Feminino , Gana/epidemiologia , Humanos , Ivermectina , Oncocercose/tratamento farmacológico
6.
Lupus ; 29(8): 970-975, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32316846

RESUMO

INTRODUCTION: The nervous system modulates rheumatic diseases in neurogenic inflammation (NI). Nerve growth factor (NGF) plays a pivotal role in NI and chronic nociceptive pain. However, the role of NGF in autoimmune inflammatory diseases is not well understood. The aim of this study was to analyse NGF high- (TrkA) and low-affinity (p75) receptors on all major leucocyte subsets of patients with systemic lupus erythematosus (SLE) as a potential indicator of NI. METHODS: A total of 13 patients were analysed by fluorescence-activated cell sorting and compared to 13 healthy control (HC) subjects. Patients were also stratified for high or low disease activity (CRP, ESR, SLEDAI, ANA, anti-dsDNA and C3/C4). Statistics included the Kruskal-Wallis test and Mann-Whitney U-test. RESULTS: When comparing patients and HC, TrkA was not differentially expressed. In contrast, p75 was increased on CD16+ and CD56+ leucocytes in patients. CD11c+ dendritic cells (DC) were in total increased in SLE. DCs were also significantly elevated in active patients. Furthermore, we found an intermediate CD11b+ population strongly expressing TrkA in patients and HC. CONCLUSION: We demonstrate for the first time differential NGF receptor expression in SLE. The increased CD11c+ DCs might indicate additional activation in SLE.


Assuntos
Células Dendríticas/metabolismo , Leucócitos Mononucleares/metabolismo , Lúpus Eritematoso Sistêmico/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptor trkA/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Adulto , Idoso , Antígeno CD11c , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Clin Infect Dis ; 61(4): 517-26, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25948064

RESUMO

BACKGROUND: Ivermectin (IVM) has been the drug of choice for the treatment of onchocerciasis. However, there have been reports of persistent microfilaridermia in individuals from an endemic area in Ghana after many rounds of IVM, raising concerns of suboptimal response or even the emergence of drug resistance. Because it is considered risky to continue relying only on IVM to combat this phenomenon, we assessed the effect of targeting the Onchocerca volvulus Wolbachia endosymbionts with doxycycline for these individuals with suboptimal response. METHODS: One hundred sixty-seven patients, most of them with multiple rounds of IVM, were recruited in areas with IVM suboptimal response and treated with 100 mg/day doxycycline for 6 weeks. Three and 12 months after doxycycline treatment, patients took part in standard IVM treatment. RESULTS: At 20 months after treatment, 80% of living female worms from the placebo group were Wolbachia positive, whereas only 5.1% in the doxycycline-treated group contained bacteria. Consistent with interruption of embryogenesis, none of the nodules removed from doxycycline-treated patients contained microfilariae, and 97% of those patients were without microfilaridermia, in contrast to placebo patients who remained at pretreatment levels (P < .001). Moreover, a significantly enhanced number of dead worms were observed after doxycycline. CONCLUSIONS: Targeting the Wolbachia in O. volvulus is effective in clearing microfilariae in the skin of onchocerciasis patients with persistent microfilaridermia and in enhanced killing of adult worms after repeated standard IVM treatment. Strategies can now be developed that include doxycycline to control onchocerciasis in areas where infections persist despite the frequent use of IVM. CLINICAL TRIALS REGISTRATION: ISRCTN 66649839.


Assuntos
Antibacterianos/administração & dosagem , Doxiciclina/administração & dosagem , Onchocerca volvulus/efeitos dos fármacos , Onchocerca volvulus/fisiologia , Oncocercose/tratamento farmacológico , Wolbachia/efeitos dos fármacos , Adolescente , Adulto , Animais , Método Duplo-Cego , Feminino , Filaricidas/administração & dosagem , Gana , Humanos , Ivermectina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Onchocerca volvulus/microbiologia , Placebos/administração & dosagem , Resultado do Tratamento , Adulto Jovem
8.
Exp Eye Res ; 127: 243-51, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25135789

RESUMO

During human ocular development, expression of proteins varies in different maturation stages. This study aims to characterize structures in human fetal eyes stained by the lymphatic marker podoplanin (D2-40) with emphasis on the stage of maturation and the presence of intraocular lymphatic structures. Formalin-fixed paraffin-embedded eyes from 40 human fetuses between 10 and 38 weeks of gestation (WoG) were investigated. Immunohistochemical stains were performed for D2-40, LYVE-1 as a secondary lymphatic marker, and CD34 as a control for endothelial reactivity. A semiquantitative analysis of antigen expression in different segments of the eye was performed by light microscopy. The intensity of antigen expression was graded with a score ranging from 0 to 3. Podoplanin expression was found with a variable intensity in 97.5% of the eyes, in particular in lymphatic vessels of the conjunctiva (n = 26), conjunctival and corneal epithelium (n = 33), corneal endothelium (n = 4), trabecular meshwork (n = 28), and optic nerve sheaths (n = 23). A slight, equivocal staining reaction was noted in the choroid (n = 14). There was a correlation of antigen reactivity and the gestational age for corneal endothelial reactivity in earlier gestational stages (p = 0.003) and trabecular meshwork in older eyes (p = 0.031). D2-40 positive Müller cells were detected in two eyes ≥32 WoG. Thus, aside from conjunctival lymphatic vessels, podoplanin was expressed in several structures of the human fetal eye and the ocular adnexae at different gestational stages. Podoplanin positive structures were also found in the choroid and the chamber angle. However, lymphatic vessels or its progenitors could not be unequivocally identified in intraocular structures during 10-38 weeks of gestation. There is no evidence from our data that transient intraocular lymphactics develop in the fetal eye between 10 and 38 weeks of gestation.


Assuntos
Túnica Conjuntiva/embriologia , Córnea/embriologia , Vasos Linfáticos/embriologia , Glicoproteínas de Membrana/metabolismo , Nervo Óptico/embriologia , Malha Trabecular/embriologia , Antígenos CD34/metabolismo , Biomarcadores/metabolismo , Túnica Conjuntiva/metabolismo , Córnea/metabolismo , Feminino , Feto , Idade Gestacional , Humanos , Técnicas Imunoenzimáticas , Vasos Linfáticos/metabolismo , Masculino , Nervo Óptico/metabolismo , Inclusão em Parafina , Fixação de Tecidos , Malha Trabecular/metabolismo , Proteínas de Transporte Vesicular/metabolismo
9.
Graefes Arch Clin Exp Ophthalmol ; 252(1): 155-62, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24193350

RESUMO

BACKGROUND: Evaluation of the lens, including cataractous changes, is often of paramount importance in the classification of fetal syndromes or forensic questions. On histology, the crystalline lens is - especially in fetal and infant eyes - an organ susceptible to numerous artifacts. Thus, the aim of our study was to study various factors (including fixatives) that might have an impact on lens histomorphology. METHODS: Twenty eyes from ten fetuses (formalin fixation: n = 10, glutaraldehyde fixation: n = 10), matched for gestational age and abortion (spontaneous vs. induced), were investigated macroscopically and by light microscopy. Sections were stained with routine hematoxylin & eosin (H&E), and periodic acid schiff (PAS). The age of the fetal eyes ranged from 15 to 36 weeks of gestation. Lens artifacts were analyzed and compared to fetal and adult lenses with definitive cataractous changes. In addition, 34 eyes from 27 fetuses with trisomy 21 were investigated for lens changes. RESULTS: All lenses showed artifacts of varying extent, in particular globules, vacuoles, clefts, anterior/posterior capsular separation, subcapsular proteinaceous material, fragmentation of the lens capsule/epithelium, and a posterior umbilication. Glutaraldehyde-fixed lenses displayed less artifacts compared to those fixed in formalin. Slight differences in the appearance of artifacts were found dependent on the fixative (formaldehyde vs glutaraldehyde) and the kind of abortion (iatrogenous vs spontaneous). The gestational age did not have a significant influence on the type and extent of lens artifacts. The lenses from fetuses with trisomy 21 displayed similar lens artifacts with no specific findings. CONCLUSIONS: Alterations in fetal lens morphology are extremely frequent and variable. These artifacts have to be carefully taken into account when interpreting post-mortem findings. Thus, the postmortem diagnosis of a fetal cataract should be made with great caution, and should include, in adherence to our proposed diagnostic flow diagram, the macroscopic lens assessment. Reference slides with a proven cataract are recommended for comparison in equivocal cases.


Assuntos
Artefatos , Técnicas de Preparação Histocitológica , Cristalino/embriologia , Cristalino/patologia , Síndrome de Down/patologia , Feto , Fixadores , Idade Gestacional , Humanos
10.
Sci Rep ; 13(1): 13785, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37612446

RESUMO

The non-filarial and non-communicable disease podoconiosis affects around 4 million people and is characterized by severe leg lymphedema accompanied with painful intermittent acute inflammatory episodes, called acute dermatolymphangioadenitis (ADLA) attacks. Risk factors have been associated with the disease but the mechanisms of pathophysiology remain uncertain. Lymphedema can lead to skin lesions, which can serve as entry points for bacteria that may cause ADLA attacks leading to progression of the lymphedema. However, the microbiome of the skin of affected legs from podoconiosis individuals remains unclear. Thus, we analysed the skin microbiome of podoconiosis legs using next generation sequencing. We revealed a positive correlation between increasing lymphedema severity and non-commensal anaerobic bacteria, especially Anaerococcus provencensis, as well as a negative correlation with the presence of Corynebacterium, a constituent of normal skin flora. Disease symptoms were generally linked to higher microbial diversity and richness, which deviated from the normal composition of the skin. These findings show an association of distinct bacterial taxa with lymphedema stages, highlighting the important role of bacteria for the pathogenesis of podoconiosis and might enable a selection of better treatment regimens to manage ADLA attacks and disease progression.


Assuntos
Elefantíase , Linfedema , Humanos , Bactérias Anaeróbias , Perna (Membro) , Pele
11.
Front Med (Lausanne) ; 10: 1099926, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36817770

RESUMO

Background: Novel drugs or drug combinations that kill or permanently sterilize adult Onchocerca volvulus worms would be very helpful for treatment and elimination of onchocerciasis. In absence of a reliable biomarker for viable adult worms, histopathological assessment of worms within onchocercal nodules is a standard method to determine macrofilaricidal activity. The goal of the present study was to determine the agreement between two independent experts in the analysis of nodule sections and to assess the value of digital imaging as a means of standardizing the analysis. Material and methods: Two expert microscopists independently assessed 605 nodules by direct microscopy. At least two sections with two different stains hematoxylin & eosin (H&E, APR immunostain) of paraffin-embedded, ethanol-fixed whole-nodule cross-sections were analyzed. After variables were identified prone to observer discrepancies, we performed a second study to compare consolidated results for 100 nodules obtained by the two readers by microscopy and by analysis of scanned, high resolution digital images (20x magnification). The last data set analyzed was a quality panel of 100 nodules that has been previously examined by microscopy, and included additional immunostains for Wolbachia endobacteria. These slides were digitalized, read by the two assessors and results were compared with original microscopy results. Results: The degree of agreement between assessors varied for different parameters. Agreement for female worm counts in nodules was approximately 80%, while agreement regarding female worm viability was 98%. There were no major differences observed between results obtained by microscopy or digital images. Good agreement for important parameters was also observed for the nodules of the quality panel. Conclusion: Nodule analysis by experienced microscopists was reproducible with regard to important parameters such as identification of living female worms or detection of normal embryogenesis. Assessments varied more for other parameters, and we recommend continued use of two independent readers for detailed analyzes. Analysis of scanned images provided similar results to direct microscopy. This facilitates training and comparison of nodule findings by readers in different locations. Analysis of high quality digital images that can be viewed remotely should improve the quality and availability of nodule assessments that are primary endpoints for onchocerciasis clinical trials.

12.
Front Trop Dis ; 42023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38655130

RESUMO

Filariae are vector borne parasitic nematodes, endemic in tropical and subtropical regions causing avoidable infections ranging from asymptomatic to stigmatizing and disfiguring disease. The filarial species that are the major focus of our institution's research are Onchocerca volvulus causing onchocerciasis (river blindness), Wuchereria bancrofti and Brugia spp. causing lymphatic filariasis (elephantiasis), Loa loa causing loiasis (African eye worm), and Mansonella spp causing mansonellosis. This paper aims to showcase the contribution of our institution and our collaborating partners to filarial research and covers decades of long research spanning basic research using the Litomosoides sigmodontis animal model to development of drugs and novel diagnostics. Research with the L. sigmodontis model has been extensively useful in elucidating protective immune responses against filariae as well as in identifying the mechanisms of filarial immunomodulation during metabolic, autoimmune and infectious diseases. The institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany has also been actively involved in translational research in contributing to the identification of new drug targets and pre-clinical drug research with successful and ongoing partnership with sub-Saharan Africa, mainly Ghana (the Kumasi Centre for Collaborative Research (KCCR)), Cameroon (University of Buea (UB)) and Togo (Laboratoire de Microbiologie et de Contrôle de Qualité des Denrées Alimentaires (LAMICODA)), Asia and industry partners. Further, in the direction of developing novel diagnostics that are sensitive, time, and labour saving, we have developed sensitive qPCRs as well as LAMP assays and are currently working on artificial intelligence based histology analysis for onchocerciasis. The article also highlights our ongoing research and the need for novel animal models and new drug targets.

13.
PLoS One ; 18(6): e0285689, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37267236

RESUMO

BACKGROUND: Life-style metabolic diseases are steadily rising, not only in developed countries, but also in low- and middle-income countries, presenting a global health problem. Metabolic disorders like type 2 diabetes and cardiovascular diseases are among the ten leading causes of death defined by the WHO in 2019. Results from animal and observational human studies suggest a connection between the decline in human helminth infections and rise of life-style-associated metabolic diseases in developing regions. This trial was designed to investigate filarial infections and their impact on metabolic diseases in Cameroon. We hypothesize that the induction of regulatory immune responses during filarial infection reduces obesity-induced low-grade inflammatory immune responses and thereby improves metabolic parameters, whereas anthelmintic treatment abolishes this protective effect. METHODS/DESIGN: Participants infected with Mansonella perstans, Onchocerca volvulus and/or Loa loa being lean (BMI <25), overweight (BMI >25 and <30) or clinically obese (BMI ≥30) from Littoral regions of Cameroon will be evaluated for their parasitological, immunological, metabolic and biochemical profile before and after treatment of their parasitic infections. Anthropomorphic measurements and a detailed questionnaire will complement our analysis. The investigation will assess blood immune cell populations, serum adipokines and cytokines that could be influenced by the parasite infection and/or metabolic diseases. Further, parameters like blood glucose, homeostatic model assessment of insulin resistance (HOMA-IR), circulating lipids and circulating makers of liver function will be monitored. Parameters will be assessed before treatment, 12 and 18 months after treatment. CONCLUSION: The focus of this study is to obtain a comprehensive metabolic profile of the participants in rural areas of Cameroon and to investigate the relationship between filarial immunomodulation and metabolic diseases. This study will elucidate the effect of anti-filarial treatment on the metabolic and immunological parameters that partake in the development of insulin resistance, narrowing in on a potential protective effect of filarial infections on metabolic diseases. TRIAL REGISTRATION: doi.org/10.1186/ISRCTN43845142, ISRCTN43845142 February 2020 Trial title Effects of filarial parasite infection on type 2 diabetes Issue date: 27.10.22, V.1.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Loíase , Mansonelose , Onchocerca volvulus , Animais , Humanos , Mansonella , Loa , Mansonelose/parasitologia , Camarões , Loíase/parasitologia , Obesidade
14.
Pathogens ; 12(6)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37375499

RESUMO

Chronic lymphedema caused by infection of Wuchereria bancrofti is a disfiguring disease that leads to physical disability, stigmatization, and reduced quality of life. The edematous changes occur mainly on the lower extremities and can progress over time due to secondary bacterial infections. In this study, we characterized participants with filarial lymphedema from Ghana and Tanzania as having low (stage 1-2), intermediate (stage 3-4), or advanced (stage 5-7) lymphedema to determine CD4+ T cell activation patterns and markers associated with immune cell exhaustion. A flow cytometry-based analysis of peripheral whole blood revealed different T cell phenotypes within participants with different stages of filarial lymphedema. In detail, increased frequencies of CD4+HLA-DR+CD38+ T cells were associated with higher stages of filarial lymphedema in patients from Ghana and Tanzania. In addition, significantly increased frequencies of CCR5+CD4+ T cells were seen in Ghanaian participants with advanced LE stages, which was not observed in the Tanzanian cohort. The frequencies of CD8+PD-1+ T cells were augmented in individuals with higher stage lymphedema in both countries. These findings show distinct activation and exhaustion patterns in lymphedema patients but reveal that immunological findings differ between West and East African countries.

15.
PLoS Negl Trop Dis ; 16(8): e0010129, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35926012

RESUMO

BACKGROUND: Lymphatic filariasis (LF) causes chronic morbidity, which usually manifests as lymphedema or hydrocele. Mass drug administration (MDA) began in Kassena Nankana East Municipal (KNEM) and Nabdam, two hotspot districts in the Upper East Region in Ghana, in 2000 and 2005, respectively. This cross-sectional study evaluated the impact of 15 years of MDA on the control of LF as determined by circulating filarial antigen (CFA) and microfilariae assessment in the KNEM and the Nabdam districts. METHODOLOGY/PRINCIPAL FINDINGS: A total of 7,453 participants from eight sub-districts in the two hotspot districts (KNEM: N = 4604; Nabdam: N = 2849) were recruited into the study. The overall CFA prevalence as determined by the FTS was 19.6% and 12.8% in the KNEM and Nabdam districts, respectively. Manyoro, a sub-district on the border with Burkina Faso, recorded the highest CFA prevalence of 26% in the KNEM. Assessment of microfilariae and Og4C3 antigen was done from 1009 (KNEM: N = 799 (79.2%); Nabdam: N = 210 (20.8%)) randomly selected FTS-positive (N = 885) and FTS-negative (N = 124) individuals. The Og4C3 antigen was found in 22.6%/23.0% of the selected individuals (KNEM/Nabdam), whereas the night blood revealed microfilariae in only 0.7%/0.5%. CONCLUSIONS/SIGNIFICANCE: Using the WHO endorsed FTS, CFA prevalence exceeded the long-standing <2% threshold-which may need revision and validation. Surprisingly, the Og4C3 ELISA showed positive results in only about one-fifth of the FTS positive samples. However, even this result would not have met the <2% CFA criteria for LF elimination. In contrast, projections from the microfilariae results revealed a halt in LF transmission. The global elimination target was due in 2020 but has been extended to 2030 since this could not be met. Focused MDA intervention intensification on seasonal migrants and non-compliers, and implementation of alternative treatment strategies may suffice for the elimination of the disease.


Assuntos
Filariose Linfática , Animais , Antígenos de Helmintos , Estudos Transversais , Filariose Linfática/tratamento farmacológico , Filariose Linfática/epidemiologia , Filariose Linfática/prevenção & controle , Gana/epidemiologia , Humanos , Masculino , Administração Massiva de Medicamentos/métodos , Microfilárias , Prevalência , Wuchereria bancrofti
16.
Eur J Med Res ; 25(1): 59, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33228795

RESUMO

BACKGROUND: Dosing recommendations for the treatment of pregnancy-acquired toxoplasmosis are empirical and widely based on experimental data. There are no pharmacological data on pregnant women with acute Toxoplasma gondii infection under treatment with pyrimethamine (PY) and sulfadiazine (SA) and our study intends to tighten this gap. METHODS: In this retrospective case-control study, we included 89 pregnant women with primary Toxoplasma infection (PT) treated with PY (50 mg first dose, then 25 mg/day), SA (50 mg/kg of body weight/day), and folinic acid (10-15 mg per week). These were compared to a group of 17 women with acute ocular toxoplasmosis (OT) treated with an initial PY dose of 75 mg, thereafter 25 mg twice a day but on the same SA and folinic acid regimen. The exact interval between drug intake and blood sampling and co-medication had not been recorded. Plasma levels of PY and SA were determined 14 ± 4 days after treatment initiation using liquid chromatography-mass spectrometry and compared using the Mann-Whitney U test at a p < 0.05 level. RESULTS: In 23 PT patients (26%), SA levels were below 20 mg/l. Fifteen of these 23 patients (17% of all patients) in parallel presented with PY levels below 700 µg/l. Both drug concentrations differed remarkably between individuals and groups (PY: PT median 810 µg/l, 95% CI for the median [745; 917] vs. OT 1230 µg/l [780; 1890], p = 0.006; SA: PT 46.2 mg/l [39.9; 54.4] vs. OT 70.4 mg/l [52.4; 89], p = 0.015) despite an identical SA dosing scheme. CONCLUSIONS: SA plasma concentrations were found in the median 34% lower in pregnant women with PT compared to OT patients and fell below a lower reference value of 50 mg/l in a substantial portion of PT patients. The interindividual variability of plasma concentrations in combination with systematically lower drug levels and possibly a lower compliance in pregnant women may thus account for a still not yet supportable transmission risk. Systematic drug-level testing in PT under PY/SA treatment deserves to be considered.


Assuntos
Complicações Parasitárias na Gravidez/tratamento farmacológico , Pirimetamina/uso terapêutico , Sulfadiazina/uso terapêutico , Toxoplasma/efeitos dos fármacos , Toxoplasmose Ocular/tratamento farmacológico , Toxoplasmose/tratamento farmacológico , Adolescente , Adulto , Antiprotozoários/sangue , Antiprotozoários/uso terapêutico , Estudos de Casos e Controles , Quimioterapia Combinada , Feminino , Humanos , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Pirimetamina/sangue , Estudos Retrospectivos , Sulfadiazina/sangue , Toxoplasma/fisiologia , Toxoplasmose/parasitologia , Toxoplasmose Ocular/parasitologia , Resultado do Tratamento , Adulto Jovem
17.
PLoS Negl Trop Dis ; 14(11): e0008839, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33180780

RESUMO

Morbidity burden of lymphatic filariasis (LF) relies on the information from the Mass Drug Administration (MDA) programme where Community Health Volunteers (CHVs) passively report cases identified. Consequently, the exact prevalence of morbidity cases is not always accurate. The use of mobile phone technology to report morbidity cases was piloted in Ghana using a text-based short messaging service (SMS) tool by CHVs. Though successful, illiterate CHVs could not effectively use the SMS tool. The aim of this study was to evaluate the use of a mobile phone-based Interactive Voice Response System (mIVRS) by CHVs in reporting LF morbidity cases and acute dermatolymphangioadenitis (ADLA) attacks in Ghana. The mIVRS was designed as a surveillance tool to capture LF data in Kassena Nankana Districts of Ghana. One hundred CHVs were trained to identify and report lymphedema and hydrocele cases as well as ADLA attacks by calling a hotline linked to the mIVRS. The system asked a series of questions about the disease condition. The ability of the CHV to report accurately was assessed and the data from the mIVRS were compared with the paper records from the CHVs and existing MDA programme records from the same communities and period. Higher numbers of lymphedema and hydrocele cases were recorded by the CHVs using the mIVRS (n = 590 and n = 103) compared to the paper-based reporting (n = 417 and n = 76) and the MDA records (n = 154 and n = 84). Female CHVs, CHVs above 40 years, and CHVs with higher educational levels were better at paper-based reporting (P = 0.007, P = 0.001, P = 0.049 respectively). The system, when fully developed and linked to national databases, may help to overcome underreporting of morbidity cases and ADLA attacks in endemic communities. The system has the potential to be further expanded to other diseases.


Assuntos
Telefone Celular , Filariose Linfática/epidemiologia , Monitoramento Epidemiológico , Linfedema/epidemiologia , Hidrocele Testicular/epidemiologia , Adulto , Idoso , Animais , Notificação de Doenças/métodos , Feminino , Gana/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Wuchereria bancrofti/isolamento & purificação , Adulto Jovem
18.
Trans R Soc Trop Med Hyg ; 114(12): 954-961, 2020 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33258944

RESUMO

BACKGROUND: Prior to carrying out clinical trials, it is important to assess the health status of the study participants to be able to interpret subsequent changes that may be related to the effects of the treatments during the follow-up of patients. This study presents the clinical, haematological and biochemical profiles of podoconiosis patients prior to their involvement in the PodoLEDoxy clinical trial. METHODS: All lower limb lymphoedema patients visiting the centre were screened and a podoconiosis diagnosis was based on clinical manifestation and detailed medical history. Patients who satisfied the eligibility criteria were enrolled in the study and their demographic data, vital signs and medical history were collected followed by biochemical and haematological examinations. RESULTS: Of the 222 participants enrolled in the study, 55.4% and 41.4% had either stage 3 or 2 podoconiosis as their highest stages, respectively. On physical examination, gastritis (46%) and poor vision (2.7%) were the most prevalent health issues identified. The majority of haematological and biochemical values were within the normal range except for mean platelet volume (47.7%), plateletcrit (58.1%), platelet distribution width (66.2%), mean corpuscular volume (67.6%) and red cell distribution width-standard deviation (79.3%), where >40% of the study participants had values out of the normal. CONCLUSION: The clinical, haematological and biochemical profiles of the study participants were largely within the normal range except for certain haematological parameters that might be worth investigating.


Assuntos
Elefantíase , Linfedema , Camarões/epidemiologia , Elefantíase/diagnóstico , Elefantíase/epidemiologia , Índices de Eritrócitos , Humanos , Linfedema/epidemiologia , Linfedema/etiologia
19.
Parasit Vectors ; 13(1): 155, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228663

RESUMO

BACKGROUND: As new lymphatic filariasis infections are eliminated through mass chemotherapy, previously affected individuals are left with the sequellae, especially chronic progressive lymphoedema. Currently this is managed by careful attention to limb hygiene to prevent infection. Studies over the past 15 years have suggested that the incorporation of doxycycline treatment may arrest or even reverse progression of lymphoedema. Most of this work has been observational or based on small studies, and if this intervention is effective, studies need to be conducted on a larger scale and under diverse geographical and social conditions before it can be incorporated into treatment policy. METHODS/DESIGN: The double-blind, placebo-controlled study was designed to investigate the impact of six weeks treatment with doxycycline added to standard limb hygiene on early stage filarial lymphoedema in five sites in Africa and the Indian subcontinent. One site in Cameroon is selected for studying lymphoedema in podoconiosis. Each site was individually powered with the potential to undertake a meta-analysis on completion. Evaluation methods followed those used in Ghana in 2012 with additions resulting from advances in technology. The details of the core protocol and how it was varied to take account of differing situations at each of the sites are provided. The study will enrol up to 1800 patients and will complete in mid-2021. CONCLUSIONS: This paper provides details of what challenges were faced during its development and discusses the issues and how they were resolved. In particular, the reasons for inclusion of new technology and the problems encountered with the supply of drugs for the studies are described in detail. By making these details available, it is hoped that the study protocol will help others interested in improving treatment for filarial lymphoedema in the design of future studies. Trial registration India: Clintrials.gov. NCT02929121 registered 10 Oct 2016: https://clinicaltrials.gov/ct2/show/NCT02929121 Mali: Clintrials.gov. NCT02927496 registered 7 Oct 2016: https://clinicaltrials.gov/ct2/show/NCT0292749 Sri Lanka: Clintrials.gov. NCT02929134 registered 10 Oct 2016: https://clinicaltrials.gov/ct2/show/NCT02929134 Ghana: ISRCTN. 14042737 registered 10 July 2017: https://doi.org/10.1186/ISRCTN14042737 Tanzania: ISRCTN. 65756724 registered 21 July 2017: https://doi.org/10.1186/ISRCTN65756724 Cameroon: ISRCTN. 1181662 registered 25 July 2017: https://doi.org/10.1186/ISRCTN11881662.


Assuntos
Doxiciclina , Filariose Linfática , Elefantíase , Linfedema , Humanos , Camarões , Doença Crônica , Método Duplo-Cego , Doxiciclina/provisão & distribuição , Doxiciclina/uso terapêutico , Elefantíase/tratamento farmacológico , Filariose Linfática/tratamento farmacológico , Gana , Higiene , Índia , Linfedema/tratamento farmacológico , Mali , Sri Lanka , Tanzânia
20.
Am J Trop Med Hyg ; 101(1): 84-92, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31162017

RESUMO

Treating Mansonella perstans is challenged by the low efficacy of registered antihelminthics. Wolbachia endobacteria provide an alternative treatment target because depletion results in amicrofilaremia in filarial infections with Wuchereria bancrofti and Onchocerca volvulus infections. This open-label, randomized study sought to confirm that i) Wolbachia are present in M. perstans in Ghana and ii) doxycycline treatment will deplete Wolbachia and cause a slow, sustained decline in microfilariae (MF). Two hundred and two Ghanaians with M. perstans infection were randomized into early (immediate) and delayed (6 months deferred) treatment groups, given doxycycline 200 mg/day for 6 weeks, and monitored for MF and Wolbachia levels at baseline, 4, 12, and 24 months after the study onset (= time of randomization and start of treatment for the early group). Per protocol analysis revealed that the median MF/mL in the early group declined from 138 at baseline to 64 at month 4 and further to 0 at month 12. In the delayed group, MF load did not change from a baseline median of 97 to 102 at month 4 but declined to 42 at month 12, that is, 6 months after receiving treatment, trailing the early group as expected. By month 24, both treatment groups had reached a median MF level of 0. After treatment, Wolbachia were depleted from MF by ≥ 1-log drop compared with baseline levels. We conclude that M. perstans in Ghana harbor Wolbachia that are effectively depleted by doxycycline with subsequent reduction in MF loads, most likely because of interruption of fertility of adult worms.


Assuntos
Antibacterianos/uso terapêutico , Doxiciclina/uso terapêutico , Mansonella , Mansonelose/tratamento farmacológico , Mansonelose/epidemiologia , Adolescente , Adulto , Animais , Criança , Feminino , Gana/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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