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1.
Parasitology ; 147(14): 1718-1722, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32829714

RESUMO

Hookworms are some of the most widespread of the soil-transmitted helminths (STH) with an estimated 438.9 million people infected. Until relatively recently Ancylostoma ceylanicum was regarded as a rare cause of hookworm infection in humans, with little public health relevance. However, recent advances in molecular diagnostics have revealed a much higher prevalence of this zoonotic hookworm than previously thought, particularly in Asia. This study examined the prevalence of STH and A. ceylanicum in the municipalities of Palapag and Laoang in the Philippines utilizing real-time polymerase chain reaction (PCR) on stool samples previously collected as part of a cross-sectional survey of schistosomiasis japonica. Prevalence of hookworm in humans was high with 52.8% (n = 228/432) individuals positive for any hookworm, 34.5% (n = 149/432) infected with Necator americanus, and 29.6% (n = 128/432) with Ancylostoma spp; of these, 34 were PCR-positive for A. ceylanicum. Considering dogs, 12 (n = 33) were PCR-positive for A. ceylanicum. This is the first study to utilize molecular diagnostics to identify A. ceylanicum in the Philippines with both humans and dogs infected. Control and elimination of this zoonotic hookworm will require a multifaceted approach including chemotherapy of humans, identification of animal reservoirs, improvements in health infrastructure, and health education to help prevent infection.


Assuntos
Ancylostoma/isolamento & purificação , Ancilostomíase/epidemiologia , Ancilostomíase/veterinária , Doenças do Cão/epidemiologia , Adolescente , Adulto , Idoso , Ancilostomíase/parasitologia , Animais , Criança , Pré-Escolar , Doenças do Cão/parasitologia , Cães , Fezes/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Filipinas/epidemiologia , Prevalência , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Solo/parasitologia , Adulto Jovem
2.
J Infect Dis ; 216(12): 1611-1622, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29029307

RESUMO

Background: Schistosomiasis japonica remains a major public health and socioeconomic concern in Southeast Asia. Sensitive and accurate diagnostics can play a pivotal role in achieving disease elimination goals. Methods: We previously reported a novel droplet digital polymerase chain reaction (ddPCR) assay targeting the mitochondrial gene nad1 to diagnose schistosomiasis japonica. The tool identified both prepatent and patent infections using Schistosoma japonicum DNA isolated from serum, urine, salivary glands, and feces in a murine model. The assay was validated here using clinical samples collected from 412 subjects resident in an area moderately endemic for schistosomiasis in the Philippines. Results: S. japonicum DNA present in human stool, serum, urine, and saliva was detected quantitatively with high sensitivity. The capability to diagnose cases of human schistosomiasis using noninvasively collected clinical samples, the higher level of sensitivity obtained compared with the microscopy-based Kato-Katz test, and the capacity to quantify infection intensity have important public health implications for schistosomiasis control and programs targeting other neglected tropical diseases. Conclusions: This verified ddPCR method represents a valuable new tool for the diagnosis and surveillance of schistosomiasis, particularly in low-prevalence and low-intensity areas approaching elimination and in monitoring where disease emergence or re-emergence is a concern.


Assuntos
DNA de Helmintos/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase/métodos , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Estudos Transversais , DNA de Helmintos/genética , Modelos Animais de Doenças , Fezes/parasitologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Camundongos , Pessoa de Meia-Idade , NADH Desidrogenase/genética , Filipinas , Prevalência , Glândulas Salivares/parasitologia , Schistosoma japonicum/genética , Sensibilidade e Especificidade , Soro/parasitologia , Urina/parasitologia , Adulto Jovem
3.
Parasitology ; 144(8): 1005-1015, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28274280

RESUMO

The current World Health Organization strategic plan targets the elimination of schistosomiasis as a public health problem by 2025 and accurate diagnostics will play a pivotal role in achieving this goal. DNA-based detection methods provide a viable alternative to some of the commonly used tests, notably microscopy and serology, for the diagnosis of schistosomiasis. The detection of parasite cell-free DNA in different clinical samples is a recent valuable advance, which provides significant benefits for accurate disease diagnosis. Here we validated a novel duplex droplet digital PCR assay for the diagnosis of Chinese (SjC) and Philippine (SjP) strains of Schistosoma japonicum infection in a mouse model. The assay proved applicable for both SjC and SjP infections and capable of detecting infection at a very early intra-mammalian stage in conveniently obtainable samples (urine and saliva) as well as in serum and feces. The target DNA copy numbers obtained in the assay showed a positive correlation with the infection burden assessed by direct traditional parasitology. The potential to detect parasite DNA in urine and saliva has important practical implications for large-scale epidemiological screening programmes in the future, particularly in terms of logistical convenience, and the assay has the potential to be a valuable additional tool for the diagnosis of schistosomiasis japonica.


Assuntos
Variações do Número de Cópias de DNA , DNA de Helmintos/análise , Reação em Cadeia da Polimerase/métodos , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/diagnóstico , Animais , Sangue/parasitologia , China , Modelos Animais de Doenças , Fezes/parasitologia , Feminino , Humanos , Camundongos , Filipinas , Saliva/parasitologia , Esquistossomose Japônica/parasitologia , Sensibilidade e Especificidade , Urina/parasitologia
4.
Clin Microbiol Rev ; 28(4): 939-67, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26224883

RESUMO

Schistosomiasis is a major neglected tropical disease that afflicts more than 240 million people, including many children and young adults, in the tropics and subtropics. The disease is characterized by chronic infections with significant residual morbidity and is of considerable public health importance, with substantial socioeconomic impacts on impoverished communities. Morbidity reduction and eventual elimination through integrated intervention measures are the focuses of current schistosomiasis control programs. Precise diagnosis of schistosome infections, in both mammalian and snail intermediate hosts, will play a pivotal role in achieving these goals. Nevertheless, despite extensive efforts over several decades, the search for sensitive and specific diagnostics for schistosomiasis is ongoing. Here we review the area, paying attention to earlier approaches but emphasizing recent developments in the search for new diagnostics for schistosomiasis with practical applications in the research laboratory, the clinic, and the field. Careful and rigorous validation of these assays and their cost-effectiveness will be needed, however, prior to their adoption in support of policy decisions for national public health programs aimed at the control and elimination of schistosomiasis.


Assuntos
Saúde Pública/tendências , Esquistossomose/diagnóstico , Medicina Tropical/tendências , Animais , Política de Saúde/tendências , Humanos , Caramujos/parasitologia
5.
BMC Nephrol ; 15: 103, 2014 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-24988874

RESUMO

BACKGROUND: Exact mechanism of causation of chronic kidney disease of unknown etiology (CKDu) in Sri Lanka is not described to date, despite the identification of possible multiple risk factors. Questions have been raised as to why only some are affected while others remain intact, though they are inhabitants of the same locality. METHODS: Comparative studies were carried out, assessing urinary ß2 microglobulin (ß2m) and the dietary patterns of CKDu patients and age sex matched non-CKDu subjects. Urinary ß2m levels of spot urine samples were analyzed using the Enzyme-linked Immunosorbent assay (ELISA) and dietary patterns were studied using twenty four hour dietary recalls and frequency consumption of foods of animal origin performed on three occasions at six months intervals within a period of one and half years. RESULTS: The mean urinary ß2m level of CKDu patients from Medawachchiya was significantly (p<0.05) higher when compared with that of the non-CKDu subjects. The mean urinary ß2m level of the non-CKDu subjects was within the reference limits for spot urine samples (0 - 0.3 µg/mL). White raw rice was the staple diet of both CKDu patients and non-CKDu subjects and the level of consumption was almost the same. The consumption of fresh water fish products of CKDu patients under high (14, 14%), moderate (36, 36%), low (26, 26%) and less (20, 20%) categories did not show significant variations (p>0.05) compared to non-CKDu subjects. CONCLUSIONS: Staple food in diet and the consumption pattern of CKDu patients from Medawachchiya were similar to that of non-CKDu subjects from the same area despite their urinary ß2m concentration being significantly higher.


Assuntos
Dieta/estatística & dados numéricos , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/urina , Microglobulina beta-2/urina , Biomarcadores/sangue , Causalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Medição de Risco , Fatores de Risco , Sri Lanka/epidemiologia
6.
Int Health ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38487983

RESUMO

BACKGROUND: There is limited knowledge about the stigma associated with cutaneous leishmaniasis (CL) in Sri Lanka. To ensure that leishmaniasis researchers focus on CL-associated stigma, we provide an evidence-based framework that can be used in future research. METHODS: We conducted a systematic review on CL-associated stigma using international evidence and carried out a multimethod qualitative study in the Anuradhapura district in Sri Lanka. Based on that, we identified manifestations of stigma, drivers and facilitators that we synthesised to develop a conceptual framework on CL-associated stigma. RESULTS: Our framework consists of drivers, facilitators and self-stigma experienced by people with CL. Stigma drivers included fear, misbeliefs and misconceptions about CL; the belief that wounds are disfiguring; the treatment burden and implied blame. Facilitators that reduced stigma included knowledge of the curability of CL and awareness that CL is not contagious. The nature of social interactions in rural communities enhanced stigma formation. We identified various enacted, felt and internalised stigma experiences of people with CL. CONCLUSIONS: We developed a conceptual framework of the stigma associated with CL that can be used to develop targeted interventions to increase CL awareness, address stigma and improve the quality of life for CL patients.

7.
Front Public Health ; 11: 1249637, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37736084

RESUMO

Background: Schistosomiasis, a disease caused by parasites of the genus Schistosoma, remains a global public health threat. This study aimed to validate the diagnostic performance of a recently developed gold immunochromatographic assay (GICA) for the detection of S. japonicum infection in a rural endemic area of the Philippines. Methods: Human clinical samples were collected from 412 subjects living in Laoang and Palapag municipalities, Northern Samar, the Philippines. The presence of Schistosoma-specific antibodies in serum samples was tested with the SjSAP4-incorporated GICA strips and the results were converted to fully quantitative data by introducing an R value. The performance of the established GICA was further compared with other diagnostic tools, including the Kato-Katz (KK) technique, point-of-care circulating cathodic antigen (POC-CCA), droplet digital (dd) PCR, and enzyme-linked immunosorbent assays (ELISAs). Results: The developed GICA strip was able to detect KK positive individuals with a sensitivity of 83.3% and absolute specificity. When calibrated with the highly sensitive faecal ddPCR assay, the immunochromatographic assay displayed an accuracy of 60.7%. Globally, the GICA assay showed a high concordance with the SjSAP4-ELISA assay. The schistosomiasis positivity rate determined by the GICA test was similar to those obtained with the SjSAP4-ELISA assay and the ddPCR assay performed on serum samples (SR_ddPCR), and was 2.3 times higher than obtained with the KK method. Conclusion: The study further confirms that the developed GICA is a valuable diagnostic tool for detecting light S. japonicum infections and implies that this point-of-care assay is a viable solution for surveying endemic areas of low-intensity schistosomiasis and identifying high-priority endemic areas for targeted interventions.


Assuntos
Esquistossomose Japônica , Humanos , Esquistossomose Japônica/diagnóstico , Imunoensaio , Ensaio de Imunoadsorção Enzimática , Fezes , Ouro
8.
Front Microbiol ; 13: 1051575, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36452928

RESUMO

The current study developed and evaluated the performance of a urine-based enzyme-linked immunosorbent assay (ELISA) for the screening of Schistosoma japonicum infection in a human cohort (n = 412) recruited from endemic areas, Northern Samar, the Philippines. The diagnostic performance of the urine ELISA assay was further compared with the Kato-Katz (KK) technique, serum-based ELISA assays, point-of-care circulating cathodic antigen (POC-CCA) urine cassette test, and droplet digital (dd)PCR assays performed on feces, serum, urine, and saliva samples, which were designated as F_ddPCR, SR_ddPCR, U_ddPCR, and SL_ddPCR, respectively. When urine samples concentrated 16× were assessed, the SjSAP4 + Sj23-LHD-ELISA (U) showed sensitivity/specificity values of 47.2/93.8% for the detection of S. japonicum infection in KK-positive individuals (n = 108). The prevalence of S. japonicum infection in the total cohort determined by the urine ELISA assay was 48.8%, which was lower than that obtained with the F_ddPCR (74.5%, p < 0.001), SR_ddPCR (67.2%, p < 0.001), and SjSAP4 + Sj23-LHD-ELISA (S) (66.0%, p < 0.001), but higher than that determined by the Sj23-LHD-ELISA (S) (24.5%, p < 0.001), POC-CCA assay (12.4%, p < 0.001), and SL_ddPCR (25.5%, p < 0.001). Using the other diagnostic tests as a reference, the urine ELISA assay showed a sensitivity between 47.2 and 56.9%, a specificity between 50.7 and 55.2%, and an accuracy between 49.3 and 53.4%. The concentrated urine SjSAP4 + Sj23-LHD-ELISA developed in the current study was more sensitive than both the KK test and POC-CCA assay, and showed a comparable level of diagnostic accuracy to that of the U_ddPCR. However, its diagnostic performance was less robust than that of the F_ddPCR, SR_ddPCR, and SjSAP4 + Sj23-LHD-ELISA (S) assays. Although they are convenient and involve a highly acceptable non-invasive procedure for clinical sample collection, the insufficient sensitivity of the three urine-based assays (the urine ELISA assay, the U_ddPCR test, and the POC-CCA assay) will limit their value for the routine screening of schistosomiasis japonica in the post mass drug administration (MDA) era, where low-intensity infections are predominant in many endemic areas.

9.
PLoS One ; 17(1): e0263188, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35085360

RESUMO

BACKGROUND: Schistosomiasis is a neglected tropical parasitic and chronic disease affecting hundreds of millions of people. Adult schistosomes reside in the blood stream of the definitive mammalian host. These helminth parasites possess two epithelial surfaces, the tegument and the gastrodermis, both of which interact with the host during immune evasion and in nutrient uptake. METHODS: Female ARC Swiss mice (4-6 weeks old) were infected percutaneously with Schistosoma japonicum cercariae freshly shed from Oncomelania hupensis quadrasi snails (Philippines strain). Fluorescent in situ hybridisation (FISH) was performed by using fresh adult S. japonicum perfused from those infected mice. Adult S. japonicum worms were processed to isolate the tegument from the carcass containing the gastrodermis; blood and bile were collected individually from infected and uninfected mice. Total DNA extracted from all those samples were used for microbiome profiling. RESULTS: FISH and microbiome profiling showed the presence of bacterial populations on two epithelial surfaces of adult worms, suggesting they were distinct not only from the host blood but also from each other. Whereas microbial diversity was reduced overall in the parasite epithelial tissues when compared with that of host blood, specific bacterial taxa, including Anoxybacillus and Escherichia, were elevated on the tegument. Minimal differences were evident in the microbiome of host blood during an active infection, compared with that of control uninfected blood. However, sampling of bile from infected animals identified some differences compared with controls, including elevated levels of Limnohabitans, Clostridium and Curvibacter. CONCLUSIONS: Using FISH and microbial profiling, we were able to demonstrate, for the first time, that bacteria are presented on the epithelial surfaces of adult schistosomes. These schistosome surface-associated bacteria, which are distinct from the host blood microenvironment, should be considered as a new and important component of the host-schistosome interaction. The importance of individual bacterial species in relation to schistosome parasitism needs further elucidation.


Assuntos
Sangue/microbiologia , Epitélio/microbiologia , Microbiota/genética , Schistosoma japonicum/microbiologia , Esquistossomose Japônica/sangue , Animais , Anoxybacillus/genética , Bile/microbiologia , Cercárias , Clostridium/genética , Comamonadaceae/genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Modelos Animais de Doenças , Escherichia coli/genética , Feminino , Hibridização in Situ Fluorescente/métodos , Masculino , Camundongos , RNA Ribossômico 16S/genética , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/parasitologia , Caramujos/parasitologia
10.
Infect Dis Poverty ; 10(1): 121, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34556183

RESUMO

BACKGROUND: Zoonotic schistosomiasis, caused by Schistosoma japonicum, remains a major public health problem in the Philippines. This study aimed to evaluate the commercially available rapid diagnostic point-of-care circulating cathodic antigen (POC-CCA) test in detecting individuals infected with S. japonicum in a human cohort from an endemic area for schistosomiasis japonica in the Philippines. METHODS: Clinical samples were collectedin 18 barangays endemic for S. japonicum infection in Laoang and Palapag municipalities, Northern Samar, the Philippines, in 2015. The presence of CCA in filter-concentrated urine samples (n = 412) was evaluated using the commercial kits and the results were converted to images, which were further analyzed by ImageJ software to calculate R values. The diagnostic performance of the immunochromatographic POC-CCA test was compared using the Kato-Katz (KK) procedure, in-house enzyme-linked immunosorbent assays (ELISAs) and droplet digital (dd) PCR assays as reference. RESULTS: The POC-CCA test was able to detect S. japonicum-infected individuals in the cohort with an eggs per gram of faeces (EPG) more than or equal to 10 with sensitivity/specificity values of 63.3%/93.3%. However, the assay showed an inability to diagnose schistosomiasis japonica infections in all cohort KK-positive individuals, of which the majority had an extremely low egg burden (EPG: 1-9). The prevalence of S. japonicum infection in the total cohort determined by the POC-CCA test was 12.4%, only half of that determined by the KK method (26.2%). When compared with the ELISAs and ddPCR assays as a reference, the POC-CCA assay was further shown to be a test with low sensitivity. Nevertheless, the assay exhibited significant positive correlations with egg burden determined by the KK technique and the target gene copy number index values determined by the ddPCR assays within the entire cohort. CONCLUSIONS: By using in silico image analysis, the POC-CCA cassette test could be converted to a quantitative assay to avoid reader-variability. Because of its low sensitivity, the commercially available POC-CCA assay had limited potential for determining the status of a S. japonicum infection in the target cohort. The assay should be applied with caution in populations where schistosome parasites (especially S. japonicum) are present at low infection intensity.


Assuntos
Antígenos de Helmintos/sangue , Fezes/parasitologia , Sistemas Automatizados de Assistência Junto ao Leito , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/diagnóstico , Testes Sorológicos/métodos , Animais , Anti-Helmínticos/uso terapêutico , Antígenos de Helmintos/análise , Ensaio de Imunoadsorção Enzimática , Humanos , Doenças Negligenciadas/epidemiologia , Filipinas/epidemiologia , Reação em Cadeia da Polimerase , Prevalência , Schistosoma japonicum/imunologia , Esquistossomose Japônica/tratamento farmacológico , Esquistossomose Japônica/epidemiologia , Sensibilidade e Especificidade
11.
J Med Case Rep ; 14(1): 50, 2020 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-32303247

RESUMO

BACKGROUND: Melioidosis is a potentially fatal bacterial infection caused by Burkholderia pseudomallei. The existence of melioidosis in Sri Lanka was once unheard of, and entertaining it as a diagnosis in clinical practice was extremely rare. CASE PRESENTATION: In this case report, we describe the clinical, epidemiological, and longitudinal follow-up data of a 58-year-old previously healthy Sinhalese woman who presented to our hospital with protracted febrile illness of 5 weeks' duration, later developing multiple abscesses at different sites of the body. There was a significant delay in confirming the diagnosis of melioidosis by isolating B. pseudomallei from blood and pus cultures. The patient recovered fully with a prolonged course of antibiotics and has remained in good health over the last 13 years without recurrence. Despite being immunocompetent, she had contracted the infection by a brief contact with mud soil in a footpath. CONCLUSIONS: A high index of clinical suspicion along with laboratory support is needed to confirm the diagnosis of melioidosis. Treatment with sensitive antibiotics over a long duration is needed, and longitudinal follow-up is essential to detect recurrences. This case raised awareness and created renewed interest in studies of melioidosis in Sri Lanka.


Assuntos
Melioidose/diagnóstico , Antibacterianos/administração & dosagem , Burkholderia pseudomallei/isolamento & purificação , Feminino , Humanos , Melioidose/tratamento farmacológico , Pessoa de Meia-Idade , Convulsões/etiologia , Sri Lanka
12.
Int J Parasitol ; 50(3): 217-225, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32135180

RESUMO

Polyparasitism, involving soil-transmitted helminths. and Schistosoma blood flukes, is common in low to middle income countries. These helminths impact on the gut environment and can cause changes to the gut microbiome composition. Here we examined the gut microbiome in individuals with polyparasitism from two human cohorts in the Philippines utilising DNA sequencing-based profiling. Multiple helminth species infections were high with 70.3% of study participants harbouring at least two parasite species, and 16% harbouring at least five species. Increased numbers of helminth co-infections, in particular with the gut-resident soil-transmitted helminths, were significantly associated with increased bacterial diversity; however no significant parasite-gut microbiome associations were evident for individuals infected only with Schistosoma japonicum. In general, a healthy gut is associated with high bacterial diversity, which in these human cohorts may be the result of helminth-mediated immune modulation, or due to changes in the gut environment caused by these parasitic helminths.


Assuntos
Coinfecção , Microbioma Gastrointestinal/genética , Helmintíase/epidemiologia , Helmintos/isolamento & purificação , Esquistossomose/epidemiologia , Adolescente , Adulto , Albendazol/uso terapêutico , Ancylostoma/isolamento & purificação , Ancylostomatoidea/isolamento & purificação , Animais , Ascaris/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Criança , Pré-Escolar , Estudos de Coortes , Coinfecção/microbiologia , Coinfecção/parasitologia , Fezes/microbiologia , Fezes/parasitologia , Feminino , Genes Bacterianos , Helmintíase/tratamento farmacológico , Helmintos/genética , Interações Hospedeiro-Parasita , Humanos , Masculino , Metagenômica , Interações Microbianas , Pessoa de Meia-Idade , Patologia Molecular , Filipinas/epidemiologia , Schistosoma/isolamento & purificação , Esquistossomose/tratamento farmacológico , Solo/parasitologia , Trichuris/isolamento & purificação , Adulto Jovem
13.
PLoS Negl Trop Dis ; 13(3): e0007228, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30830925

RESUMO

BACKGROUND: Zoonotic schistosomiasis in Asia, caused by Schistosoma japonicum, remains a major public health concern in China and the Philippines. The developing epidemiological and socio-economic picture of the disease in endemic areas necessitates the development of affordable and highly accurate field diagnostics as an important component in evaluating ongoing integrated control and elimination efforts. METHODS: Three diagnostic methods, namely Kato-Katz (KK) stool microscopy, ELISA and droplet digital (dd) PCR assays, were compared by detecting infection in a total of 412 participants from an area moderately endemic for schistosomiasis in the Philippines. RESULTS: This comprehensive comparison further defined the diagnostic performance and features for each assay. Compared with the ddPCR assay analysing DNA from faeces (F_ddPCR), which exhibited the highest sensitivity, the SjSAP4 + Sj23-LHD-ELISA had the best accuracy (67.2%) among all five ELISA assays assessed. Schistosomiasis prevalence determined by the SjSAP4 + Sj23-LHD-ELISA and ddPCRs was similar and was at least 2.5 times higher than obtained with the KK method. However, the agreement between these assays was low. In terms of cost and logistical convenience, the SjSAP4 + Sj23-LHD-ELISA represents a cost-effective assay with considerable diagnostic merits. In contrast, although the ddPCR assays exhibited a high level of diagnostic performance, the high cost and the need for specialized equipment presents a major obstacle in their application in screening campaigns. CONCLUSION: The SjSAP4 + Sj23-LHD-ELISA represents a cost-effective tool for the diagnosis of schistosomiasis that could prove an important component in the monitoring of integrated control measures as elimination draws closer, whereas the ddPCR assays, in addition to their high sensitivity and specificity, are capable of quantifying infection intensity. However, the high cost of ddPCR hinders its wider application in screening programs, although it could be a valuable reference in the development and improvement of other diagnostic assays.


Assuntos
Doenças Endêmicas , Ensaio de Imunoadsorção Enzimática , Reação em Cadeia da Polimerase , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/diagnóstico , Adulto , Idoso , Animais , Anticorpos Anti-Helmínticos/imunologia , Criança , Estudos de Coortes , Fezes/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Filipinas/epidemiologia , Prevalência , Schistosoma japonicum/imunologia , Esquistossomose Japônica/sangue , Esquistossomose Japônica/epidemiologia , Esquistossomose Japônica/parasitologia , Sensibilidade e Especificidade
14.
Trop Med Infect Dis ; 3(3)2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30274477

RESUMO

Despite extensive efforts over the last few decades, the global disease burden of schistosomiasis still remains unacceptably high. This could partly be attributed to the lack of accurate diagnostic tools for detecting human and animal schistosome infections in endemic areas. In low transmission and low prevalence areas where schistosomiasis elimination is targeted, case detection requires a test that is highly sensitive. Diagnostic tests with low sensitivity will miss individuals with low infection intensity and these will continue to contribute to transmission, thereby interfering with the efficacy of the control measures operating. Of the many diagnostic approaches undertaken to date, the detection of schistosome DNA using DNA amplification techniques including polymerase chain reaction (PCR) provide valuable adjuncts to more conventional microscopic and serological methods, due their accuracy, high sensitivity, and the capacity to detect early pre-patent infections. Furthermore, DNA-based methods represent important screening tools, particularly in those endemic areas with ongoing control where infection prevalence and intensity have been reduced to very low levels. Here we review the role of DNA diagnostics in the path towards the control and elimination of schistosomiasis.

15.
EBioMedicine ; 24: 237-246, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28943229

RESUMO

Schistosoma japonicum is stubbornly persistent in China and the Philippines. Fast and accurate diagnostic tools are required to monitor effective control measures against schistosomiasis japonica. Promising antigen candidates for the serological diagnosis of schistosomiasis japonica have generally been identified from the Chinese strain of S. japonicum. However, the Chinese (SjC) and Philippine (SjP) strains of S. japonicum express a number of clear phenotypic differences, including aspects of host immune responses. This feature thereby emphasized the requirement to determine whether antigens identified as having diagnostic value for SjC infection are also suitable for the diagnosis of SjP infection. In the current study, 10 antigens were selected for comparison of diagnostic performance of the SjP infection using ELISA. On testing of sera from 180 subjects in the Philippines, SjSAP4 exhibited the best diagnostic performance with 94.03% sensitivity and 98.33% specificity using an optimized serum dilution. In another large scale testing with 412 serum samples, a combination (SjSAP4+Sj23-LHD (large hydrophilic domain)) provided the best diagnostic outcome with 87.04% sensitivity and 96.67% specificity. This combination could be used in future for serological diagnosis of schistosomiasis in the Philippines, thereby representing an important component for monitoring integrated control measures.


Assuntos
Antígenos de Helmintos/imunologia , Schistosoma japonicum/imunologia , Esquistossomose Japônica/diagnóstico , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Camundongos , Filipinas , Esquistossomose Japônica/imunologia , Sensibilidade e Especificidade
16.
Trends Parasitol ; 32(5): 378-391, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26847654

RESUMO

Parasites often cause devastating diseases and represent a significant public health and economic burden. More accurate and convenient diagnostic tools are needed in support of parasite control programmes in endemic regions, and for rapid point-of-care diagnosis in nonendemic areas. The detection of cell-free DNA (cfDNA) is a relatively new concept that is being applied in the current armamentarium of diagnostics. Here, we review the application of cfDNA detection with nucleic acid amplification tests for the diagnosis and evaluation of different human parasitic infections and highlight the significant benefits of the approach using non-invasive clinical samples.


Assuntos
Biomarcadores/análise , DNA/análise , Técnicas de Amplificação de Ácido Nucleico , Doenças Parasitárias/diagnóstico , Saúde Pública/tendências , Animais , Biomarcadores/sangue , Biomarcadores/urina , DNA/sangue , DNA/urina , Humanos , Parasitos/genética , Parasitos/isolamento & purificação , Saliva/química , Saliva/parasitologia
17.
J Microbiol Methods ; 125: 19-27, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27021661

RESUMO

Schistosomiasis is a chronically debilitating helminth infection with a significant socio-economic and public health impact. Accurate diagnostics play a pivotal role in achieving current schistosomiasis control and elimination goals. However, many of the current diagnostic procedures, which rely on detection of schistosome eggs, have major limitations including lack of accuracy and the inability to detect pre-patent infections. DNA-based detection methods provide a viable alternative to the current tests commonly used for schistosomiasis diagnosis. Here we describe the optimisation of a novel droplet digital PCR (ddPCR) duplex assay for the diagnosis of Schistosoma japonicum infection which provides improved detection sensitivity and specificity. The assay involves the amplification of two specific and abundant target gene sequences in S. japonicum; a retrotransposon (SjR2) and a portion of a mitochondrial gene (nad1). The assay detected target sequences in different sources of schistosome DNA isolated from adult worms, schistosomules and eggs, and exhibits a high level of specificity, thereby representing an ideal tool for the detection of low levels of parasite DNA in different clinical samples including parasite cell free DNA in the host circulation and other bodily fluids. Moreover, being quantitative, the assay can be used to determine parasite infection intensity and, could provide an important tool for the detection of low intensity infections in low prevalence schistosomiasis-endemic areas.


Assuntos
DNA de Helmintos/análise , Reação em Cadeia da Polimerase/métodos , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/diagnóstico , Adulto , Animais , DNA de Helmintos/metabolismo , Fezes/parasitologia , Corantes Fluorescentes , Genes de Helmintos , Genes Mitocondriais , Humanos , Retroelementos , Schistosoma japonicum/genética , Schistosoma japonicum/crescimento & desenvolvimento , Esquistossomose Japônica/parasitologia , Sensibilidade e Especificidade
18.
BMC Res Notes ; 8: 130, 2015 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-25889835

RESUMO

BACKGROUND: Meticulous fluid management is the mainstay of treatment in dengue fever that is currently governed by consensus guidelines rather than by strong research evidence. To examine this issue we audited the fluid requirement of a cohort of adult patients with dengue fever (DF) and dengue haemorrhagic fever (DHF) in a tertiary care clinical setting. RESULTS: This retrospective cohort study was conducted from July 2012 to January 2013 in Teaching Hospital, Peradeniya, Sri Lanka. Adult patients with confirmed dengue infection managed according to the national and WHO guidelines were included. Their fluid requirement was audited once data collection was over in both DF and DHF groups. Out of 302 patients, 209 (69%) had serological confirmation of dengue infection, comprising 62 (30%) patients gone into critical phase of DHF. Mean age of the DHF group was 30 years (range 12-63 years) and included more males (n = 42, 68%, p < 0.05). Their mean duration of fever on admission and total duration of fever were 4 days and 6 days respectively. DHF group had high incidence of vomiting, abdominal pain and flushing, lowest platelet counts and highest haematocrit values compared to DF group. In DHF group, the mean total daily requirements of fluid from 2(nd) to 7(th) day were 2123, 2733, 2846, 2981, 3139 and 3154 milliliters respectively to maintain a safe haematocrit value and the vital parameters. However, in DF group the fluid requirement was lowest on 3(rd) day (2158 milliliters). DHF group had significantly high fluid requirement on 5(th) -7(th) day compared to DF group (p < 0.05). CONCLUSIONS: Patients in critical phase of DHF required a higher volume of fluids from the 3(rd) day of fever and again on 5(th) to 7(th) day of fever. Despite being an audit, these finding could be useful in future updates of guidelines and designing research.


Assuntos
Líquidos Corporais/metabolismo , Dengue/terapia , Hidratação/tendências , Hospitais de Ensino , Dengue Grave/terapia , Dor Abdominal/fisiopatologia , Adolescente , Adulto , Criança , Dengue/fisiopatologia , Feminino , Rubor/fisiopatologia , Hematócrito , Humanos , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Estudos Retrospectivos , Dengue Grave/fisiopatologia , Sri Lanka , Atenção Terciária à Saúde , Vômito/fisiopatologia
19.
Toxicon ; 93: 85-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25450799

RESUMO

In recent years, stings of a lethal scorpion species were recorded from Jaffna Peninsula in the northern dry zone of Sri Lanka. This species was identified as Hottentotta tamulus (Scorpiones: Buthidae) which is the Indian red scorpion commonly found in Maharashtra, India. The Teaching Hospital, Jaffna recorded 84 H. tamulus stings over a year in 2012 and of them, 23 cases provided offending scorpions (proven cases). Three localities in Jaffna were recorded as hotspots of scorpion stings namely Palali, Achchuvali and Karainagar. Of the proven cases, 13 (57%) and 10 (43%) were males and females respectively and had a mean age of 30 years (SD ± 20 years). Among them, 5 (22%) were children below 12 years. In 13 (57%) patients stings occurred inside their houses including two children (40%). Six (26%) stings occurred at night when the victims were in sleep. Median time taken to arrive at the hospital from the time of stinging was 58 min (range 8-550 min). Signs of over activation of autonomic nervous system predominated the clinical picture-tachycardia in 14 (61%), high blood pressure in 11 (48%), excessive sweating in 9 (39%), excessive salivation in 5 (22%), hypotension in 4 (17%) and piloerection in 3 (13%). Children showed higher predilection to develop tachycardia - 4 (80%) and excessive salivation - 3 (60%). Priapism was not observed and 17 (74%) patients have developed intense pain at the site of sting. The commonest ECG change was tachycardia (73%) and occasional T wave inversion. Prazosin as a treatment was given to 22 (96%) patients. All patients made recovery and 13 (57%) patients left the hospital within two days. In future, there is a potential risk of spreading this species to elsewhere in the country and may disturb the ecological balance.


Assuntos
Mordeduras e Picadas/epidemiologia , Mordeduras e Picadas/fisiopatologia , Escorpiões , Animais , Feminino , Humanos , Incidência , Masculino , Salivação/efeitos dos fármacos , Venenos de Escorpião/toxicidade , Sri Lanka/epidemiologia , Taquicardia/patologia
20.
BMC Res Notes ; 7: 398, 2014 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-24964804

RESUMO

BACKGROUND: Leptospirosis is an important zoonotic disease of variable severity and is a common cause of acute kidney injury (AKI) in tropics. However the knowledge on long term renal outcome in leptospirosis is scarce. This study aims to assess the long-term renal outcome of AKI caused by leptospirosis. FINDINGS: Hospital records of patients who had developed AKI following leptospirosis (Serologically confirmed) presented to two Teaching Hospitals in Kandy district over 3 years from 2007 were studied. A total of 44 patients were included and they had been followed up at least for one year in out patient clinics with regular assessment including renal status. Renal histology was studied in two patients. The primary outcome measure was normalization of renal function at one year. Of the 44 patients, 31 were in the risk and injury stage (Group 1), and the rest of them were in the failure stage (Group 2) under RIFLE criteria. Of group 2 patients, 11 had abnormal renal functions on discharge. Their mean serum creatinine and GFR values on discharge were 392 mmol/l and 20 ml/min/1.73 m2. Other two patients had full renal recovery whilst in the hospital. Nine in the group 2 required renal replacement therapy by means of peritoneal dialysis, intermittent haemodialysis or haemofiltration. Seventeen out of the total had persistently abnormal renal functions on discharge. Of them 13 recovered their renal functions to normal. Four patients (9%) who belonged to group 2, had persistently abnormal renal functions after first year compatible with stage 3 chronic kidney disease (CKD). Renal histology of two patients showed tubulointerstitial lymphocyte infiltrate, tubular atrophy and interstitial fibrosis. CONCLUSION: The long term renal outcome of AKI following leptospirosis is satisfactory as only 9% of patients had abnormal renal functions compatible with early stage of CKD. Even among them, advanced CKD or dialysis dependency had not been observed.


Assuntos
Injúria Renal Aguda/terapia , Hospitais de Ensino/estatística & dados numéricos , Leptospirose/complicações , Ambulatório Hospitalar/estatística & dados numéricos , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/fisiopatologia , Adulto , Idoso , Creatinina/sangue , Feminino , Seguimentos , Taxa de Filtração Glomerular , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Alta do Paciente/estatística & dados numéricos , Sri Lanka , Resultado do Tratamento , Adulto Jovem
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