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1.
PLoS Negl Trop Dis ; 15(8): e0009623, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34398886

RESUMO

BACKGROUND: Loa loa and Mansonella perstans-the causative agents of loiasis and mansonellosis-are vector-borne filarial parasites co-endemic in sub-Saharan Africa. Diagnosis of both infections is usually established by microscopic analysis of blood samples. It was recently established that the odds for detecting Plasmodium spp. is higher in capillary (CAP) blood than in venous (VEN) blood. In analogy to this finding this analysis evaluates potential differences in microfilaraemia of L. loa and M. perstans in samples of CAP and VEN blood. METHODS: Recruitment took place between 2015 and 2019 at the CERMEL in Lambaréné, Gabon and its surrounding villages. Persons of all ages presenting to diagnostic services of the research center around noon were invited to participate in the study. A thick smear of each 10 microliters of CAP and VEN blood was prepared and analysed by a minimum of two independent microscopists. Differences of log2-transformed CAP and VEN microfilaraemia were computed and expressed as percentages. Furthermore, odds ratios for paired data were computed to quantify the odds to detect microfilariae in CAP blood versus in VEN blood. RESULTS: A total of 713 participants were recruited among whom 52% were below 30 years of age, 27% between 30-59 years of age and 21% above 60 years of age. Male-female ratio was 0.84. Among 152 participants with microscopically-confirmed L. loa infection median (IQR) microfilaraemia was 3,650 (275-11,100) per milliliter blood in CAP blood and 2,775 (200-8,875) in VEN blood (p<0.0001), while among 102 participants with M. perstans this was 100 (0-200) and 100 (0-200), respectively (p = 0.44). Differences in linear models amount up to an average of +34.5% (95% CI: +11.0 to +63.0) higher L. loa microfilaria quantity in CAP blood versus VEN blood and for M. perstans it was on average higher by +24.8% (95% CI: +0.0 to +60.5). Concordantly, the odds for detection of microfilaraemia in CAP samples versus VEN samples was 1.24 (95% CI: 0.65-2.34) and 1.65 (95% CI: 1.0-2.68) for infections with L. loa and M. perstans, respectively. CONCLUSION: This analysis indicates that average levels of microfilaraemia of L. loa are higher in CAP blood samples than in VEN blood samples. This might have implications for treatment algorithms of onchocerciasis and loiasis, in which exact quantification of L. loa microfilaraemia is of importance. Furthermore, the odds for detection of M. perstans microfilariae was higher in CAP than in VEN blood which may pre-dispose CAP blood for detection of M. perstans infection in large epidemiological studies when sampling of large blood quantities is not feasible. No solid evidence for a higher odds of L. loa microfilariae detection in CAP blood was revealed, which might be explained by generally high levels of L. loa microfilaraemia in CAP and VEN blood above the limit of detection of 100 microfilariae/ml. Yet, it cannot be excluded that the study was underpowered to detect a moderate difference.


Assuntos
Coinfecção/patologia , Loa/isolamento & purificação , Loíase/patologia , Mansonella/isolamento & purificação , Mansonelose/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Coinfecção/epidemiologia , Coinfecção/parasitologia , Feminino , Gabão/epidemiologia , Humanos , Loíase/epidemiologia , Loíase/parasitologia , Masculino , Mansonelose/epidemiologia , Mansonelose/parasitologia , Microscopia , Pessoa de Meia-Idade , Carga Parasitária , Parasitemia , Prevalência , Testes Sorológicos , Adulto Jovem
4.
J Infect Dis ; 223(2): 287-296, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33099649

RESUMO

Mansonella perstans, a filarial nematode, infects large populations in Africa and Latin America. Recently, a potential new species, Mansonella sp "DEUX," was reported. Carriage of endosymbiotic Wolbachia opens treatment options for Mansonella infections. Within a cross-sectional study, we assessed the prevalence of filarial infections in 834 Gabonese individuals and the presence of the endosymbiont Wolbachia. Almost half of the participants (400/834 [48%]) were infected with filarial nematodes, with Mansonella sp "DEUX" being the most frequent (295/400 [74%]), followed by Loa loa (273/400 [68%]) and Mansonella perstans (82/400 [21%]). Being adult/elderly, male, and living in rural areas was associated with a higher risk of infection. Wolbachia carriage was confirmed in M. perstans and Mansonella sp "DEUX." In silico analysis revealed that Mansonella sp "DEUX" is not detected with currently published M. perstans-specific assays. Mansonella infections are highly prevalent in Gabon and might have been underreported, likely also beyond Gabon.


Assuntos
Mansonella/classificação , Mansonella/genética , Mansonelose/epidemiologia , Mansonelose/parasitologia , Animais , Portador Sadio/parasitologia , Estudos Transversais , Gabão/epidemiologia , Humanos , Loa/genética , Masculino , Epidemiologia Molecular , Reação em Cadeia da Polimerase , População Rural
5.
Infect Dis Poverty ; 9(1): 105, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32703283

RESUMO

BACKGROUND: Mansonella perstans infection can be considered one of the most neglected tropical infectious diseases. Very few studies have reported on the clinical picture caused by infection with this nematode. Therefore, our study was aimed to describe the clinical patterns and treatment of imported M. perstans infection by migrants from Africa. METHODS: The present study evaluated a large cohort of migrants who have been diagnosed, examined and treated for imported M. perstans infection at a Spanish reference center (Hospital Carlos III Tropical Medicine Unit, Madrid, Spain) over a 19-year period. Most patients voluntarily attend the emergency unit or are referred from primary care or general hospitals in Madrid. Chi-square test was used to compare the association between categorical variables. The continuous variables were compared by Student's t-test or the Mann-Whitney test. The corresponding regression models were used for multivariate analysis. RESULTS: Five hundred three cases of migrants from tropical and subtropical areas with M. perstans infection were identified. Two hundred sixty-four patients were female (52.5%). The mean age (± SD) was 44.6 ± 18.2 years (range: 16-93 years). The mean time (± SD) between the arrival in Spain and the first consultation was 8.6 ± 18.0 months. The major origin of the patients was Equatorial Guinea (97.6%). Regarding the clinical picture, 257 patients were asymptomatic (54.7%) and 228 were symptomatic (45.3%); 190 patients had pruritus (37.8%), 50 (9.9%) had arthralgia, 18 patients had Calabar-like swelling (3.6%), and 15 (3%) had abdominal pain. Four hundred forty-two (87.9%) migrants had hyper-IgE, and 340 (67.6%) had eosinophilia. One hundred ninety-five patients had coinfections with other filarial nematodes (38.8%), and 308 migrants had only M. perstans infection (61.2%). Four hundred thirty-seven cases (86.9%) had been treated with anti-filarial drugs; 292 cases were treated with one anti-filarial drug, and 145 cases were treated with combined anti-filarial therapy. Additionally, 20 (4%) cases received steroids and 38 (7.6%) cases received antihistamines. CONCLUSIONS: A long series of M. perstans infections is presented in sub-Saharan immigrants whose data indicate that it should be included in the differential diagnosis in patients with pruritus or analytical alterations such as eosinophilia or hyper-IgE presentation, and they also have a high number of coinfections with other microorganisms whose treatment needs to be protocolized.


Assuntos
Doenças Transmissíveis Importadas/epidemiologia , Doenças Transmissíveis Importadas/parasitologia , Mansonelose/epidemiologia , Adolescente , Adulto , África , Idoso , Idoso de 80 Anos ou mais , Animais , Antiparasitários/uso terapêutico , Feminino , Humanos , Masculino , Mansonella/isolamento & purificação , Mansonelose/tratamento farmacológico , Pessoa de Meia-Idade , Espanha/epidemiologia , Migrantes , Resultado do Tratamento , Adulto Jovem
6.
Parasit Vectors ; 13(1): 313, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546281

RESUMO

BACKGROUND: The Onchocercidae is a family of filarial nematodes with several species of medical or veterinary importance. Microfilariae are found in the blood and/or the dermis and are usually diagnosed in humans by microscopy examination of a blood sample or skin biopsy. The main objectives of this study were to evaluate whether filariae DNA can be detected in faecal samples of wild non-human primates (NHPs), whether the detected parasites were closely related to those infecting humans and whether filarial DNA detection in faeces is associated with co-infections with nematodes (Oesophagostumum sp. and Necator sp.) known to cause blood loss while feeding on the host intestinal mucosa. METHODS: A total of 315 faecal samples from 6 species of NHPs from Cameroon and Gabon were analysed. PCRs targeted DNA fragments of cox1 and 12S rDNA genes, to detect the presence of filariae, and the internal transcribed spacer 2 (ITS2), to detect the presence of Oesophagostomum sp. and Necator sp. infections. RESULTS: Among the 315 samples analysed, 121 produced sequences with > 90% homology with Onchocercidae reference sequences. However, 63% of the 12S rDNA and 78% of the cox1 gene sequences were exploitable for phylogenetic analyses and the amplification of the 12S rDNA gene showed less discriminating power than the amplification of the cox1 fragment. Phylogenetic analyses showed that the cox1 sequences obtained from five chimpanzee DNA faecal samples from Gabon and two from Cameroon cluster together with Mansonella perstans with high bootstrap support. Most of the remaining sequences clustered together within the genus Mansonella, but the species could not be resolved. Among the NHP species investigated, a significant association between filarial DNA detection and Oesophagostomum sp. and Necator sp. infection was observed only in gorillas. CONCLUSIONS: To our knowledge, this is the first study reporting DNA from Mansonella spp. in faecal samples. Our results raise questions about the diversity and abundance of these parasites in wildlife, their role as sylvatic reservoirs and their potential for zoonotic transmission. Future studies should focus on detecting variants circulating in both human and NHPs, and improve the molecular information to resolve or support taxonomy classification based on morphological descriptions.


Assuntos
Fezes/parasitologia , Mansonella/genética , Mansonelose/veterinária , Necator/classificação , Oesophagostomum/classificação , Primatas/parasitologia , Animais , Camarões , Ciclo-Oxigenase 1/genética , DNA de Helmintos/genética , Teste em Amostras de Sangue Seco , Gabão , Genótipo , Necator/genética , Oesophagostomum/genética , Filogenia
7.
Clin Infect Dis ; 71(8): 1990-1993, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31995172

RESUMO

Mansonella ozzardi and Mansonella perstans infections both cause mansonellosis but are usually treated differently. Using a real-time polymerase chain reaction assay and deep sequencing, we reveal the presence of mansonellosis coinfections that were undetectable by standard diagnostic methods. Our results confirm mansonellosis coinfections and have important implications for the disease's treatment and diagnosis.


Assuntos
Coinfecção , Mansonelose , Animais , Brasil/epidemiologia , Coinfecção/diagnóstico , Coinfecção/epidemiologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mansonella
8.
Washington, D.C.; OPAS; 2019-12-11.
em Português | PAHO-IRIS | ID: phr-51762

RESUMO

[Antecedentes]: Este documento reúne um conjunto de recomendações formuladas pela OMS e pela OPAS para ajudar os profissionais responsáveis pelos programas de controle de vetores nas Américas em nível nacional, subnacional e local a se atualizarem e tomarem decisões baseadas em evidências sobre as medidas de controle mais apropriadas para cada situação. O MIV pode ser utilizado quando o objetivo é a vigilância e o controle ou a eliminação (dependendo da situação específica) das DTVs e pode ajudar a reduzir o desenvolvimento de resistência aos inseticidas pelo uso racional desses produtos. Este documento contém instruções para a execução do mandato de 2008 da OPAS sobre o manejo integrado de vetores (resolução CD48.R8, documento CD48/13) e, em particular, complementa uma série de diretrizes da OMS publicadas em 2012: o manual para o MIV e os guias para o monitoramento e a avaliação dos indicadores do MIV, o estabelecimento de políticas para o MIV e os currículos de capacitação em MIV. A elaboração deste documento seguiu uma metodologia orientada para a obtenção das melhores evidências disponíveis sobre o MIV, tendo em conta a realidade dos países e os principais cenários de transmissão de DTVs. Espera-se que este documento operacional seja reproduzível e de fácil aplicação e que as suas mensagens sejam claras e permitam alcançar a maior eficiência possível na aplicação do MIV em cada região. Nos anexos, são apresentadas as experiências de diferentes países da Região nos quais são aplicados os conceitos do MIV.


Assuntos
Controle de Vetores , Dengue , Zika virus , Trypanosoma , Leishmania , Plasmodium , Flavivirus , Alphavirus , Rickettsia , Onchocerca , Mansonella , Wuchereria , Vírus Chikungunya , Febre Amarela , América
9.
Washington, D.C.; OPS; 2019-12-11.
em Espanhol | PAHO-IRIS | ID: phr-51760

RESUMO

[Antecedentes]: El presente documento reúne un conjunto de recomendaciones formuladas por la Organización Mundial de la Salud (OMS) y la Organización Panamericana de la Salud (OPS) para ayudar, a los profesionales encargados de los programas de control de vectores de Latinoamérica y el Caribe a nivel nacional, subnacional y local, a actualizar y tomar decisiones basadas en la evidencia sobre las medidas de control más apropiadas para cada situación específica. El MIV puede utilizarse cuando la meta es la vigilancia y el control o la eliminación (dependiendo de la situación específica) de las ETV y puede contribuir a reducir el desarrollo de la Resistencia a los insecticidas mediante el uso racional de estos productos. Este documento contiene las instrucciones para llevar a cabo el mandato de la OPS del 2008 sobre el control integrado de vectores (resolución CD48.R8, documento CD48/13) y, en particular, complementa una serie de guías de la OMS publicadas en el 2012: el manual para el MIV y las guías de seguimiento y evaluación de los indicadores de MIV, construcción de políticas para el MIV y currículos de capacitación en MIV. Para la elaboración del documento se siguió una metodología orientada a obtener la major evidencia disponible sobre el MIV, teniendo en cuenta la realidad de los países y los principals escenarios de transmisión de las ETV. Se espera que este documento operativo sea reproducible y de fácil aplicación y que sus mensajes sean claros y permitan alcanzar la mayor eficiencia posible en la aplicación del MIV en las respectivas regiones. En los anexos se presentan las experiencias de diferentes países de la Región, en las cuales se aplican conceptos de MIV.


Assuntos
Controle de Vetores , Vetores de Doenças , Trypanosoma , Leishmania , Plasmodium , Flavivirus , Alphavirus , Rickettsia , Onchocerca , Mansonella , Wuchereria , Carga Global da Doença , América
10.
Emerg Infect Dis ; 25(11): 2081-2083, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31625843

RESUMO

We reviewed Giemsa-stained thick blood smears, obtained through the national malaria surveillance program in the Amazon region of Ecuador, by light microscopy for Mansonella spp. microfilariae. Of 2,756 slides examined, 566 (20.5%) were positive. Nested PCR confirmed that the microfilariae were those of M. ozzardi nematodes, indicating that this parasite is endemic to this region.


Assuntos
Mansonella , Mansonelose/epidemiologia , Mansonelose/parasitologia , Animais , Equador/epidemiologia , Feminino , Geografia Médica , Humanos , Masculino , Mansonella/genética , Mansonella/isolamento & purificação , Mansonelose/diagnóstico , Reação em Cadeia da Polimerase , Prevalência , Vigilância em Saúde Pública
11.
Exp Parasitol ; 206: 107769, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31580876

RESUMO

BACKGROUND: Mansonellosis arises from infections with threadlike filarial nematodes in millions of individuals, especially in sub-Saharan Africa. Since infections present no overt clinical symptoms but attenuate immune responses that might lead to increased susceptibility and worsened disease course of concomitant infections, it is truly a neglected tropical disease. Nevertheless, only few studies focus on identifying suitable safe drugs for its control and little is known about the requirements for in vitro maintenance of the Mansonella perstans transmission stage. This study, therefore, evaluated the survival of M. perstans microfilariae (mf) using in vitro conditions that have been shown to promote survival of Loa loa, a closely related filarial nematode. Furthermore, the in vitro microfilaricidal effect of 15 agents was assessed on this helminth. METHODS: The ability of two basic culture media; Dulbecco's Modified Eagle's Medium (DMEM) and Roswell Park Memorial Institute (RPMI-1640) supplemented with 10% fetal bovine serum (FBS) and a monkey kidney epithelial cell line (LLC-MK2) to support the survival of M. perstans microfilariae was investigated. Subsequently, 6 anti-helminthics, 5 anti-malarials, 1 anti-microbacterial, 2 trypanocidals and 1 anti-cancer agent were tested in vitro against mf. The suitability of the culture media as well as the effect of the anti-infective agents on mf survival was assessed by scoring their motility. RESULTS: FBS supplement and additional LLC-MK2 cells significantly improved the survival of mf in DMEM and RPMI-1640 culture. In detail, RPMI-1640 supplemented with 10% FBS and LLC-MK2 cells sustained the maintenance of mf for at least 20 days (100.00 ±â€¯0.00% survival). In co-cultures with LLC-MK2 cells without serum, M. perstans mf were maintained in DMEM and RPMI-1640 medium with a motility above 99% by day 5. Mefloquine displayed the highest microfilaricidal effect in vitro followed by artesunate. CONCLUSION: Both RPMI and DMEM in the presence of LLC-MK2 cells are suitable for the maintenance of M. perstans mf in vitro. In absence of the feeder cells, the addition of 10% FBS to RPMI-1640 medium improved the parasite survival rate and motility. The microfilaricidal activity of mefloquine and artesunate on M. perstans mf was documented for the first time in this study and can therefore be considered as reference for further screening of agents against this parasite stage.


Assuntos
Artesunato/farmacologia , Filaricidas/farmacologia , Mansonella/efeitos dos fármacos , Mansonella/crescimento & desenvolvimento , Mefloquina/farmacologia , Amodiaquina/farmacologia , Animais , Antimaláricos/farmacologia , Antinematódeos/farmacologia , Área Sob a Curva , Bovinos , Linhagem Celular , Meios de Cultura/química , Haplorrinos , Ivermectina/farmacologia , Mansonella/fisiologia , Microfilárias/efeitos dos fármacos , Microfilárias/crescimento & desenvolvimento , Microfilárias/fisiologia , Movimento/efeitos dos fármacos , Rifampina/farmacologia
12.
Sci Rep ; 9(1): 10275, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311985

RESUMO

Mansonelliasis is a widespread yet neglected tropical infection of humans in Africa and South America caused by the filarial nematodes, Mansonella perstans, M. ozzardi, M. rodhaini and M. streptocerca. Clinical symptoms are non-distinct and diagnosis mainly relies on the detection of microfilariae in skin or blood. Species-specific DNA repeat sequences have been used as highly sensitive biomarkers for filarial nematodes. We have developed a bioinformatic pipeline to mine Illumina reads obtained from sequencing M. perstans and M. ozzardi genomic DNA for new repeat biomarker candidates which were used to develop loop-mediated isothermal amplification (LAMP) diagnostic tests. The M. perstans assay based on the Mp419 repeat has a limit of detection of 0.1 pg, equivalent of 1/1000th of a microfilaria, while the M. ozzardi assay based on the Mo2 repeat can detect as little as 0.01 pg. Both LAMP tests possess remarkable species-specificity as they did not amplify non-target DNAs from closely related filarial species, human or vectors. We show that both assays perform successfully on infected human samples. Additionally, we demonstrate the suitability of Mp419 to detect M. perstans infection in Culicoides midges. These new tools are field deployable and suitable for the surveillance of these understudied filarial infections.


Assuntos
Marcadores Genéticos , Mansonella/genética , Mansonelose/diagnóstico , Sequências Repetitivas de Ácido Nucleico , Análise de Sequência de DNA/métodos , África , Animais , Simulação por Computador , DNA de Protozoário/genética , Testes Diagnósticos de Rotina , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Mansonella/isolamento & purificação , Técnicas de Diagnóstico Molecular , Doenças Negligenciadas/diagnóstico , Técnicas de Amplificação de Ácido Nucleico , Sensibilidade e Especificidade , América do Sul
13.
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
14.
Parasit Vectors ; 12(1): 166, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30975194

RESUMO

BACKGROUND: Culicoides (Diptera; Ceratoponidae) are tiny, stout, blood-sucking flies with a near worldwide distribution. When present, they are often considered a biting nuisance but in addition, they are involved in the transmission of pathogens to humans, domestic and wild animals. Data on Culicoides species in the South-West region of Cameroon dates back to the 1950s. Over the decades, ecological transformation due to agriculture and deforestation may have affected the population dynamics of Culicoides and therefore our study provides an update of their bio-ecology in the region. Furthermore, the role of various Culicoides species in the transmission of parasitic filariae of the genus Mansonella remains inconclusive in this region. This study was designed to address these unknown issues and expand on current scientific knowledge. RESULTS: Eight species of Culicoides (C. bedfordi, C. inornatipennis, C. fulvithorax, C. grahamii, C. imicola, C. milnei, C. neavei and C. kumbaensis) were collected using light traps and human baits. Culicoides grahamii was the most abundant species, followed closely by C. milnei. Three species (C. milnei, C. grahamii and C. inornatipennis) were common in all observed larval development sites. Only four species (C. inornatipennis, C. fulvithorax, C. grahamii and C. milnei) were collected on humans. Anthropophilic species were more abundant (P < 0.001) in the evening (4-7 pm) when compared to the morning collections (6-9 am). After overnight fly collections using a drop trap with a human microfilaremic donor, C. milnei emerged as the potential host for transmitting Mansonella perstans. Substantial heterogeneity was observed between the trap visiting cycles of the various species (P < 0.001). The biting cycle of the main vector, C. milnei, showed two peaks (10-11 pm and 4-5 am), the highest being 10-11 pm. CONCLUSIONS: The Culicoides fauna of the South-West region of Cameroon has not changed significantly since the 1950s. Culicoides milnei was demonstrated to be the major vector of M. perstans in this part of Cameroon. It is essentially a nocturnal species which peaks in abundance between 10 and 11 pm.


Assuntos
Ceratopogonidae/fisiologia , Mansonelose/transmissão , Animais , Biodiversidade , Camarões , Feminino , Humanos , Insetos Vetores/fisiologia , Masculino , Mansonella/fisiologia
15.
Am J Trop Med Hyg ; 100(4): 914-920, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30693861

RESUMO

Infections due to Loa loa and Mansonella perstans are common yet elusive neglected filariases. Parasitological cure after treatment is very difficult to assess, as adult parasites are not accessible. Therefore, outside transmission areas, patients require a long follow-up period to ascertain the therapeutic outcome, which is impractical for non-sedentary populations such as migrants. We studied the change over time of microfilaremia, eosinophil counts, and antifilarial antibodies tested with a commercial ELISA test (Bordier Affinity Products, Crissier, Switzerland), in a retrospective cohort of patients with confirmed L. loa and M. perstans infections, to evaluate the role of serology in clinical practice. After treatment, all 22 eligible patients diagnosed in our center between 2015 and 2017 reached amicrofilaremia, with microfilarial counts decreasing sharply within 2 months. Paralleling eosinophil counts, antibodies decreased in all patients, 36% of whom reached sero-reversion or near-sero-reversion in < 20 months. These findings suggest that positive serology is not just residual from a past infection, and may be used for diagnosis even when microfilaremia is negative or cannot be performed. Interestingly, antibodies and eosinophil counts increased following some, but not all, re-treatment courses. If the rise in these parameters reflects death of macrofilariae, caution is required in interpreting high eosinophil counts and antibody titers shortly after treatment, as these may reflect no need for further treatment. To optimize patients' management, it is now pivotal to ascertain the interval between treatment and macrofilarial death and therefore whether re-treatments are required for complete clearance of parasites.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Loíase/sangue , Mansonelose/sangue , Adolescente , Adulto , Animais , Ensaio de Imunoadsorção Enzimática , Eosinófilos , Feminino , Filaricidas/uso terapêutico , Seguimentos , Humanos , Itália , Contagem de Leucócitos , Loa , Loíase/diagnóstico , Loíase/tratamento farmacológico , Estudos Longitudinais , Masculino , Mansonella , Mansonelose/diagnóstico , Mansonelose/tratamento farmacológico , Microfilárias/isolamento & purificação , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
17.
Transfusion ; 59(3): 1044-1051, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30566229

RESUMO

BACKGROUND: In the Brazilian Amazon, the filarial nematode Mansonella ozzardi co-exists with malaria parasites and thick blood smear microscopy is considered the diagnostic gold standard. Transfusion of M. ozzardi microfilariae does not establish new infections, however microfilariae can survive approximately 2 years in blood-recipients with unknown risk of pathology. Data on transfusion-transmitted filariasis are lacking. This study investigated M. ozzardi parasitemias in blood donors from decentralized centers of "Fundação Hematologia e Hemoterapia do Estado do Amazonas/HEMOAM," Northern Brazil. STUDY DESIGN AND METHODS: Cross-sectional investigation employing blood smear microscopy (n = 356) and qualitative nested-M. ozzardi-PCR (227 out of 356) in donor candidates from 19 hemocenters in interior/rural municipalities of Amazonas state. FINDINGS: Participants were mostly young males. Positivity by microscopy was 7.9% (28 out of 356) and 23.8% by M. ozzardi-PCR (54 out of 227). Parasitaemias were found in 16 out of 19 municipalities. In 54 M. ozzardi-positives, 24 were ineligible; among 30 that donated, 27 were interdicted by seropositivity (22 anti-HBc, 3 anti-HBc + HBsAg, 1 Chagas+malaria, 1 VDRL). Seropositivty was higher in M. ozzardi-PCR-positives vs M. ozzardi-PCR-negatives (OR = 15.8, 95% CI 4.5-56.1, p < 0.0001). Three M. ozzardi contaminated blood units were transfused, but no follow-up information on the recipients is available. MAIN CONCLUSIONS: Our study provides important baseline data on M. ozzardi among blood donors from the Brazilian Amazon. Further investigations in endemic areas are necessary to clarify possible association between M. ozzardi and other infections and also to elucidate whether there is any significant clinical effect upon transfusion of contaminated blood.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Mansonella/patogenicidade , Mansonelose/parasitologia , Adolescente , Adulto , Idoso , Animais , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Mansonella/isolamento & purificação , Mansonelose/epidemiologia , Pessoa de Meia-Idade , Adulto Jovem
18.
Clin Exp Immunol ; 196(1): 111-122, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30561772

RESUMO

Mansonella perstans (Mp) filariasis is present in large populations in sub-Saharan Africa, and to what extent patent Mp infection modulates the expression of immunity in patients, notably their cellular cytokine and chemokine response profile, remains not well known. We studied the spontaneous and inducible cellular production of chemokines (C-X-C motif) ligand 9 (CXCL9) [monokine induced by interferon (IFN)-γ (MIG)], CXCL-10 [inducible protein (IP)-10], chemokine (C-C motif) ligand 24 (CCL24) (eotaxin-2), CCL22 [macrophage-derived chemokine (MDC)], CCL13 [monocyte chemotactic protein-4 (MCP-4)], CCL18 [pulmonary and activation-regulated chemokine (PARC)], CCL17 [thymus- and activation-regulated chemokine (TARC)] and interleukin (IL)-27 in mansonelliasis patients (Mp-PAT) and mansonelliasis-free controls (CTRL). Freshly isolated peripheral mononuclear blood cells (PBMC) were stimulated with helminth, protozoan and bacterial antigens and mitogen [phytohaemagglutinin (PHA)]. PBMC from Mp-PAT produced spontaneously (without antigen stimulation) significantly higher levels of eotaxin-2, IL-27, IL-8, MCP-4 and MDC than cells from CTRL, while IFN-γ-IP-10 was lower in Mp-PAT. Helminth antigens activated IL-27 and MCP-4 only in CTRL, while Ascaris antigen, Onchocerca antigen, Schistosoma antigen, Entamoeba antigen, Streptococcus antigen, Mycobacteria antigen and PHA stimulated MIG release in CTRL and Mp-PAT. Notably, Entamoeba antigen and PHA strongly depressed (P < 0·0001) eotaxin-2 (CCL24) production in both study groups. Multiple regression analyses disclosed in Mp-PAT and CTRL dissimilar cellular chemokine and cytokine production levels being higher in Mp-PAT for CCL24, IL-27, IL-8, MCP-4, MDC and PARC (for all P < 0·0001), at baseline (P < 0·0001), in response to Entamoeba histolytica strain HM1 antigen (EhAg) (P < 0·0001), Onchocerca volvulus adult worm-derived antigen (OvAg) (P = 0·005), PHA (P < 0·0001) and purified protein derivative (PPD) (P < 0·0001) stimulation. In Mp-PAT with hookworm co-infection, the cellular chemokine production of CXCL10 (IP-10) was diminished. In summary, the chemokine and cytokine responses in Mp-PAT were in general not depressed, PBMC from Mp-PAT produced spontaneously and selectively inducible inflammatory and regulatory chemokines and cytokines at higher levels than CTRL and such diverse and distinctive reactivity supports that patent M. perstans infection will not polarize innate and adaptive cellular immune responsiveness in patients.


Assuntos
Quimiocinas/metabolismo , Citocinas/metabolismo , Filariose/imunologia , Interleucina-27/metabolismo , Leucócitos Mononucleares/fisiologia , Mansonella/fisiologia , Mansonelose/imunologia , Imunidade Adaptativa , África ao Sul do Saara , Animais , Antígenos de Bactérias/imunologia , Antígenos de Helmintos/imunologia , Células Cultivadas , Quimiocinas/genética , Citocinas/genética , Humanos , Imunidade Inata , Interleucina-27/genética
19.
Rev. patol. trop ; 47(3): 195-198, set. 2018. ilus
Artigo em Inglês | LILACS | ID: biblio-946912

RESUMO

Blood samples from Mansonella ozzardi infected volunteers from Vila Antimary (Amazonas State) were processed and a protocol to isolate and prepare microfilariae was carried out in order to perform Scanning Electron Microscopy (SEM) analysis. Data obtained from ultrastructure showed some undescribed structural points of the parasite such as a dimple in the anterior end of the larva and small points ­orifice-like­ that may be related to amphidial structures or simply pores. Another interesting feature was the tip of the tail which is very similar to that found in the rodent parasite Dunnifilaria meningica


Assuntos
Parasitos , Microscopia Eletrônica de Varredura , Larva , Mansonella , Microfilárias
20.
Rev. colomb. cancerol ; 22(2): 88-91, abr.-jun. 2018. graf
Artigo em Espanhol | LILACS | ID: biblio-959888

RESUMO

Resumen Las filariasis son parasitosis producidas por nemátodos hemáticos de la familia Filariidae, la Mansonella ozzardi, es uno de los agentes etiológicos distribuido ampliamente en el continente americano y en el Caribe. Presentamos el caso de una paciente de 13 años de edad, previamente diagnosticada con linfoma T de célula grande anaplásico. Como parte de la evaluación antes del segundo ciclo B de quimioterapia, se realizó un extendido de sangre periférica en el que se encontró una microfilaría tipificada como Mansonella ozzardi, se dio manejo con una dosis única de ivermectina y se logró resultado negativo en el control a las 24 horas. Actualmente la paciente se encuentra asintomática y sin evidencia de recurrencia de la parasitemia y terminando su tratamiento oncológico.


Abstract Filariasis is caused by nematodes in the blood. Mansonella ozzardi is one of the aetiological agents widely distributed in the Americas and the Caribbean. The case is presented on a paediatric patient previously diagnosed with T-cell anaplastic large cell lymphoma. As part of the evaluation before the second cycle B chemotherapy, a peripheral blood smear was performed, in which were found microfilaria, identified as Mansonella ozzardi. The treatment was a single dose of ivermectin, with a negative result being obtained at 24 hours. The patient is currently asymptomatic and with no evidence of recurrence of the parasitaemia, and able to finish the cancer treatment.


Assuntos
Humanos , Feminino , Adolescente , Linfoma de Células T , Linfoma Anaplásico de Células Grandes , Filariose , Mansonella , Doenças Parasitárias , Ivermectina , Controle , Microfilárias
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