RESUMO
Novel tools for early diagnosis and monitoring of schistosomiasis are urgently needed. This study aimed to validate parasite-derived miRNAs as potential novel biomarkers for the detection of human Schistosoma japonicum infection. A total of 21 miRNAs were initially validated by real-time-polymerase chain reaction (RT-PCR) using serum samples of S. japonicum-infected BALB/c mice. Of these, 6 miRNAs were further validated with a human cohort of individuals from a schistosomiasis-endemic area of the Philippines. RT-PCR analysis showed that two parasite-derived miRNAs (sja-miR-2b-5p and sja-miR-2c-5p) could detect infected individuals with low infection intensity with moderate sensitivity/specificity values of 66%/68% and 55%/80%, respectively. Analysis of the combined data for the two parasite miRNAs revealed a specificity of 77.4% and a sensitivity of 60.0% with an area under the curve (AUC) value of 0.6906 (P = 0.0069); however, a duplex RT-PCR targeting both sja-miR-2b-5p and sja-miR-2c-5p did not result in an increased diagnostic performance compared with the singleplex assays. Furthermore, the serum level of sja-miR-2c-5p correlated significantly with faecal egg counts, whereas the other five miRNAs did not. Targeting S. japonicum-derived miRNAs in serum resulted in a moderate diagnostic performance when applied to a low schistosome infection intensity setting.
Assuntos
Biomarcadores/sangue , MicroRNA Circulante/sangue , Schistosoma japonicum , Esquistossomose Japônica/diagnóstico , Animais , Estudos de Coortes , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Técnicas de Diagnóstico Molecular/métodos , Contagem de Ovos de Parasitas , Filipinas , RNA de Helmintos/sangue , Reação em Cadeia da Polimerase em Tempo Real , Schistosoma japonicum/genética , Schistosoma japonicum/metabolismo , Sensibilidade e EspecificidadeRESUMO
Chronic infection with Schistosoma japonicum or Schistosoma mansoni results in hepatic fibrosis of the human host. The staging of fibrosis is crucial for prognosis and to determine the need for treatment of patients with schistosomiasis. This study aimed to determine whether there is a correlation between the levels of serum exosomal micro-ribonucleic acids (miRNAs) (exomiRs) and fibrosis progression in schistosomiasis. Reference gene (RG) validation was initially carried out for the analysis of serum exomiRs expression in staging liver fibrosis caused by schistosome infection. The expression levels of liver fibrosis-associated exomiRs in serum were determined in a murine schistosomiasis model and in a cohort of Filipino schistosomiasis japonica patients (n = 104) with different liver fibrosis grades. Of twelve RG candidates validated, miR-103a-3p and miR-425-5p were determined to be the most stable genes in the murine schistosomiasis model and subjects from the schistosomiasis-endemic area, respectively. The temporal expression profiles of nine fibrosis-associated serum exomiRs, as well as their correlations with the liver pathologies, were determined in C57BL/6 mice during S. japonicum infection. The serum levels of three exomiRs (miR-92a-3p, miR-146a-5p and miR-532-5p) were able to distinguish subjects with fibrosis grades I-III from those with no fibrosis, but only the serum level of exosomal miR-146a-5p showed potential for distinguishing patients with mild (grades 0-I) versus severe fibrosis (grades II-III). The current data imply that serum exomiRs can be a supplementary tool for grading liver fibrosis in hepatosplenic schistosomiasis with moderate accuracy.
Assuntos
Cirrose Hepática/diagnóstico , MicroRNAs/sangue , Esquistossomose Japônica/complicações , Adulto , Animais , Biomarcadores/sangue , Modelos Animais de Doenças , Exossomos/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/etiologia , Cirrose Hepática/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Pessoa de Meia-Idade , Adulto JovemRESUMO
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 JovemRESUMO
PURPOSE OF REVIEW: Preventive chemotherapy is advocated for the global control and elimination of schistosomiasis. Despite the well known short-term benefits of treating patients for schistosomiasis, the impact of mass drug administration (MDA) campaigns to control the disease in the long term remains unresolved. RECENT FINDINGS: Many studies have advocated the success of MDA programs in order to attract donor funds for elimination efforts but such successes are often short-lived given the drug does not alter the life cycle of the organism or prevent reinfection. Within a matter of months to years after halting treatment, the prevalence, intensity of infection and morbidity of disease return to baseline levels. Other mitigating factors contribute to the failings of MDA campaigns namely: poverty, poor drug coverage, poor drug compliance, and, in the case of Asiatic schistosomiasis, zoonotic transmission. Genetic and innate and acquired immunologic mechanisms complicate the epidemiologic picture of schistosomiasis globally, and may contribute indirectly to MDA shortcomings. The possibility of drug resistance is an ever present concern because of the sole reliance on one drug, praziquantel. SUMMARY: Preventive chemotherapy is advocated for the global control and elimination of schistosomiasis. The short-term benefits of MDA campaigns are well documented but the long-term benefits are questionable.
Assuntos
Anti-Helmínticos/administração & dosagem , Saúde Global , Esquistossomose/tratamento farmacológico , Erradicação de Doenças/métodos , Promoção da Saúde , Humanos , Praziquantel/administração & dosagem , Prevalência , Recidiva , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Fatores SocioeconômicosRESUMO
BACKGROUND: In the Philippines, the current national control strategy for schistosomiasis is annual mass drug administration (MDA) with 40 mg/kg of praziquantel in all schistosomiasis-endemic villages with a prevalence ≥10%. METHODS: A cross-sectional survey of schistosomiasis was conducted in 2012 on 18 221 individuals residing in 22 schistosomiasis-endemic villages in the province of Northern Samar. The prevalence of schistosomiasis, intensity of Schistosoma infection, and morbidity of disease were assessed. RESULTS: Despite an active schistosomiasis-control program in Northern Samar for >30 years, which included a MDA campaign in the last 5 years, the mean prevalence of schistosomiasis among 10 435 evaluated subjects was 27.1% (95% confidence interval [CI], 26.3%-28.0%), and the geometric mean intensity of infection among 2832 evaluated subjects was 17.2 eggs per gram of feces (95% CI, 16.4-18.1). Ultrasonography revealed high levels of schistosomiasis-induced morbidity in the schistosomiasis-endemic communities. Left lobe liver enlargement (≥70 mm) was evident in 89.3% of subjects. Twenty-five percent of the study population had grade II/III liver parenchyma fibrosis, and 13.3% had splenomegaly (≥100 mm). CONCLUSIONS: MDA on its own was insufficient to control the prevalence of schistosomiasis, intensity of Schistosoma infection, or morbidity of the disease. Alternative control measures will be needed to complement the existing national MDA program.
Assuntos
Anti-Helmínticos/administração & dosagem , Praziquantel/administração & dosagem , Esquistossomose/tratamento farmacológico , Esquistossomose/prevenção & controle , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Estudos Transversais , Tratamento Farmacológico/métodos , Feminino , Pesquisa sobre Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Filipinas/epidemiologia , Prevalência , População Rural , Adulto JovemRESUMO
BACKGROUND: Schistosoma japonicum is one of three major species of blood flukes causing schistosomiasis, a disease, which continues to be a major public health issue in the Philippines. SjSAP4, a member of a multigene family of saposin-like proteins, is a recognized immunodiagnostic biomarker for schistosomiasis japonica. This study aimed to identify linear B-cell epitopes on SjSAP4 and to validate their potential as components of a multi-epitope assay for the serological diagnosis of schistosomiasis japonica. METHODOLOGY: SjSAP4-derived peptides were expressed as GST-peptide-fused proteins and these were Western blot probed with human serum samples from S. japonicum Kato-Katz (KK)-positive individuals and uninfected controls. A core epitope was further identified by Western blotting through probing a series of truncated peptides with the schistosomiasis patient sera. The diagnostic performance of the core epitope-containing peptides and the full-length SjSAP4 was evaluated by enzyme-linked immunosorbent assay (ELISA) using a panel of sera collected from subjects resident in a schistosomiasis-endemic area of the Philippines. MAIN FINDINGS: As a result of the peptide mapping, one peptide (P15) was found to be highly immunogenic in the KK-positive individuals. We subsequently showed that -S163QCSLVGDIFVDKYLD178- is a core B-cell epitope of P15. Subsequent ELISAs incorporating SjSAP4, SjSAP4-Peptide and SjSP-13V2-Peptide showed a sensitivity of 94.0%, 46.0% and 74.0%, respectively, and a specificity of 97.1%, 100% and 100%, respectively. Notably, complementary recognition of the B-cell epitopes (SjSAP4-Peptide and SjSP-13V2-Peptide) was observed in a subset of the KK-positive individuals. A dual epitope-ELISA (SjSAP4-Peptide + SjSP-13V2-Peptide-ELISA) showed a diagnostic sensitivity of 84.0% and a specificity of 100%. CONCLUSIONS/SIGNIFICANCE: In this study, -S163QCSLVGDIFVDKYLD178- was identified as a dominant linear B-cell epitope on SjSAP4. This peptide and the complementary recognition of other B-cell epitopes using sera from different KK-positive individuals can provide the basis of developing a multi-epitope assay for the serological diagnosis of schistosomiasis.
Assuntos
Schistosoma japonicum , Esquistossomose Japônica , Animais , Antígenos de Helmintos , Ensaio de Imunoadsorção Enzimática , Epitopos de Linfócito B , Humanos , Peptídeos , Saposinas , Sensibilidade e EspecificidadeRESUMO
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 EspecificidadeRESUMO
BACKGROUND: Chronic infection with Schistosoma japonicum or S. mansoni results in hepatic fibrosis of the human host. Staging fibrosis is crucial for the prognosis and to determine the rapid need of treatment in patients with schistosomiasis. METHODS: To establish whether there is a correlation between circulating microRNA (miRNA) level and fibrosis progression in schistosomiasis, ten miRNAs were selected to assess their potential in grading schistosomiasis liver fibrosis. This was done firstly in two mouse strains (C57BL/6 and BALB/c) to determine the temporal expression profiles in serum over the course of S. japonicum infection, and then within a cohort of 163 schistosomiasis japonica patients with different grades of liver fibrosis. FINDING: Four miRNAs (miR-150-5p, let-7a-5p, let-7d-5p and miR-146a-5p) were able to distinguish patients with mild versus severe fibrosis. The level of serum miR-150-5p showed the most promising potential for grading hepatic fibrosis in schistosomiasis. The diagnostic performance of miR-150-5p in discriminating mild from severe fibrosis is comparable with that of the ELF test and serum HA level. In addition, the serum levels of the four miRNAs rebounded in infected C57BL/6 mice, after 6â¯months post treatment, following the regression of liver fibrosis, thereby providing further support for the utility of these miRNAs in grading schistosomal hepatic fibrosis. INTERPRETATION: Circulating miRNAs can be a supplementary tool for assessing hepatic fibrosis in human schistosomiasis. FUND: National Health and Medical Research Council (NHMRC) of Australia (APP1102926, APP1037304 and APP1098244).
Assuntos
Ácidos Nucleicos Livres/sangue , Cirrose Hepática/sangue , MicroRNAs/sangue , Schistosoma japonicum , Schistosoma mansoni , Esquistossomose Japônica/sangue , Esquistossomose mansoni/sangue , Adulto , Animais , Feminino , Humanos , Cirrose Hepática/etiologia , Cirrose Hepática/parasitologia , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Esquistossomose Japônica/complicações , Esquistossomose mansoni/complicaçõesRESUMO
BACKGROUND: Co-parasitism is a frequent occurrence in impoverished communities in the tropics resulting in a considerable disease burden. While there are extensive reports of intestinal helminthiases, including schistosomiasis japonica, the occurrence and extent of diseases caused by intestinal protozoa (IP) have yet to be investigated in depth in the Philippines. We present a detailed analysis of polyparasitism in a rural community of Northern Samar, focusing on co-infections of IP with Schistosoma japonicum. METHODS: A descriptive cross sectional study was carried out in 2015 across 18 barangays (villages) endemic for S. japonicum in Northern Samar, the Philippines to assess the burden of human schistosomiasis and IP infections. Faecal samples collected from 412 participants from the 18 barangays were included in the final molecular analysis. A multiplex quantitative PCR assay was developed and used for the detection of Blastocystis spp., Entamoeba histolytica, Cryptosporidium spp. and Giardia duodenalis in stool samples. The findings were combined with previous results of droplet digital PCR diagnosis of individuals from the same 18 barangays infected with S. japonicum determined using the same stool samples for analysis. RESULTS: Mean age of the study participants was 40.3 years (95% CI: 38.8-41.8) with 53% (n = 218) being males. Prevalence of S. japonicum (74.5%) and Blastocystis spp. (58.7%) was significantly higher compared to other infections, with E. histolytica having the lowest prevalence (12.1%). A majority of individuals were infected with more than one parasite with two infections being most common (n = 175, 42.5%). The prevalence of individuals with two parasites was significantly higher than all others with 27.9% (n = 115) subjects harbouring a single parasite species. Of individuals with two infections, S. japonicum and Blastocystis spp. were the most common combination (n = 110, 62.9%). Examining age within the population, 58.5% (n = 38) of school-aged children and 60.1% (n = 14) of women of child bearing age harboured at least two parasite species. CONCLUSIONS: The study revealed that polyparasitism with IP infections and schistosomiasis japonica is highly prevalent in individuals in Northern Samar which likely contributes to the significant public health and socio-economic burden suffered by this population. More generally, the findings are of relevance when considering implementation of integrated control strategies for intestinal parasites.
Assuntos
Coinfecção , Enteropatias Parasitárias/complicações , Infecções por Protozoários/complicações , População Rural , Esquistossomose Japônica/complicações , Adolescente , Adulto , Criança , Feminino , Humanos , Enteropatias Parasitárias/epidemiologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Filipinas , Prevalência , Infecções por Protozoários/epidemiologia , Fatores de Risco , Esquistossomose Japônica/epidemiologia , Adulto JovemRESUMO
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 EspecificidadeRESUMO
OBJECTIVE: This study assessed the impact of annual versus biennial praziquantel treatment regimens on the prevalence, intensity of infection, and liver fibrosis dynamics of Asiatic schistosomiasis (caused by Schistosoma japonicum) among individuals residing in 18 endemic barangays in Northern Samar, Philippines. METHODS: Five hundred and sixty-five subjects who reported symptoms of gastrointestinal illness and/or were believed to have clinical morbidity based on physical examination were selected for cohort follow-up. RESULTS: The mean prevalence of schistosomiasis was 34% and the mean intensity of infection was 123.1 eggs per gram. Moderate to severe hepatic fibrosis (grade II/III) was demonstrated in approximately 25% of the study population. As expected, a greater reduction in both the prevalence and intensity of infection was documented with two treatment rounds versus one. Overall, hepatic fibrosis (grades I-III) regressed in only 24.3% of those who received a single treatment and in only 19.3% of those who received two doses. The prevalence of grade II-III fibrosis at baseline (25.2%) remained unchanged 2 years after treatment. CONCLUSIONS: These findings suggest that in order to reverse moderate to severe liver fibrosis due to schistosomiasis and improve clinical outcomes, a higher clinical dosage of praziquantel (i.e., 60-80mg/kg) may be required over an extended duration.
Assuntos
Cirrose Hepática/mortalidade , Praziquantel/administração & dosagem , Esquistossomose/tratamento farmacológico , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Esquema de Medicação , Feminino , Humanos , Cirrose Hepática/epidemiologia , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Morbidade , Filipinas/epidemiologia , Schistosoma japonicum/efeitos dos fármacos , Esquistossomose/epidemiologia , Esquistossomose/mortalidade , Esquistossomose/parasitologia , Adulto JovemRESUMO
BACKGROUND: Subclinical morbidity due to schistosomiasis was evaluated in 565 patients, and the enhanced liver fibrosis (ELF) test was assessed for the first time as a potential screening tool for disease. METHODS: The prevalence and intensity of infection were determined by Kato-Katz thick smear stool examination at baseline and 2 years after curative treatment. The degree of hepatic fibrosis was assessed by ultrasound. Non-invasive serum biomarkers of hepatic fibrosis were also evaluated. RESULTS: The baseline human prevalence and infection intensity were found to be moderately high at 34% and 123 eggs per gram, respectively. However, hepatic parenchymal fibrosis occurred in 50% of subjects, with grade II fibrosis in 19% and grade III in 6%. The ELF score and higher serum levels of tissue inhibitor of metalloproteinase 1 (TIMP-1) and hyaluronic acid (HA) correlated with the grade of liver fibrosis. CONCLUSIONS: The findings of this study demonstrated that praziquantel treatment had a short-term impact on both the prevalence and intensity of infection, but less of an impact on established morbidity. Higher TIMP-1 and HA serum levels, and an ELF cut-off score of 8 were found to be correlated with the grade of liver fibrosis; these values may, therefore, assist physicians in identifying individuals at greater risk of disease.
Assuntos
Cirrose Hepática/diagnóstico , Esquistossomose/complicações , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Humanos , Ácido Hialurônico/sangue , Cirrose Hepática/sangue , Cirrose Hepática/etiologia , Cirrose Hepática/mortalidade , Masculino , Pessoa de Meia-Idade , Morbidade , Filipinas , Praziquantel/uso terapêutico , Prevalência , Esquistossomose/tratamento farmacológico , Esquistossomose Japônica/tratamento farmacológico , Inibidor Tecidual de Metaloproteinase-1/sangue , Ultrassonografia , Adulto JovemRESUMO
Zoonotic schistosomiasis has a long endemic history in the Philippines. Human mass drug administration has been the cornerstone of schistosomiasis control in the country for the past three decades. Recent publications utilizing retrospective national survey data have indicated that the national human prevalence of the disease is <1%, hence the disease is now close to elimination. However, the evidence for such a claim is weak, given that less than a third of the human population is currently being treated annually within endemic zones and only a third of those treated actually swallow the tablets. For those who consume the drug at the single oral dose of 40mg/kg, the estimated cure rate is 52% based on a recent meta-analysis. Thus, approximately 5% of the endemic human population is in reality receiving the appropriate treatment. To compound this public health problem, most of the bovines in the endemic communities are concurrently infected but are not treated under the current national control programme. Given this evidence, it is believed that the human prevalence of schistosomiasis within endemic regions has been grossly underestimated. Inherent flaws in the reporting of national schistosomiasis prevalence data are reported here, and the problems of utilizing national retrospective data in making geographic information system (GIS) risk maps and advising policy makers of the outcomes are highlighted.
Assuntos
Esquistossomose/epidemiologia , Zoonoses/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Efeitos Psicossociais da Doença , Doenças Endêmicas , Humanos , Filipinas/epidemiologia , Prevalência , Estudos Retrospectivos , Esquistossomose/prevenção & controle , Esquistossomose/veterinária , Inquéritos e QuestionáriosRESUMO
Childhood cataracts are a major cause of treatable blindness. Early recognition, surgical intervention and appropriate follow-up after surgery can result in good visual outcomes. However, several factors may impact on the availability of such services, including lack of an available, affordable and accessible comprehensive eye care centre, financial limitations affecting coverage by the national healthcare provider, and household socioeconomic status. We report a case of congenital cataracts in a 12-year-old male adolescent from Northern Samar, the Philippines, who was left blind since birth. This case highlights the disparities in essential health services in the developing world and the challenges patients face in getting the care they need.
Assuntos
Extração de Catarata , Catarata/congênito , Países em Desenvolvimento , Acessibilidade aos Serviços de Saúde , Extração de Catarata/economia , Criança , Acessibilidade aos Serviços de Saúde/economia , Humanos , Masculino , Filipinas , Fatores SocioeconômicosRESUMO
Anorectal malformations consist of a wide spectrum of conditions which can affect both sexes and involve the distal anus and rectum as well as the urinary and genital tracts. Patients have the best chance of a good functional outcome if the condition is diagnosed early and efficient anatomic repair is promptly instituted. This report describes a rare case of imperforate anus associated with both rectovaginal and rectocutaneous fistulas in a 6-year-old Filipino girl. The case highlights shortcomings in the healthcare delivery system combined with socio-economic factors that contributed to the delay in both diagnosis and the institution of adequate treatment. Care and preventive measures that can be implemented in low-resource settings to reduce the impact of birth defects are also discussed.
Assuntos
Canal Anal/anormalidades , Canal Anal/cirurgia , Anus Imperfurado/diagnóstico , Anus Imperfurado/cirurgia , Anormalidades Congênitas/cirurgia , Fístula Retovaginal/cirurgia , Reto/anormalidades , Malformações Anorretais , Criança , Países em Desenvolvimento , Feminino , Saúde Global , Acessibilidade aos Serviços de Saúde , Humanos , Filipinas , Fístula Retovaginal/complicações , Reto/cirurgiaRESUMO
Schistosomiasis was first reported in the Philippines in 1906. A variety of treatments have been deployed to cure infection and to control the disease in the long-term. We discuss the journey to combat the disease in the Philippines and the lessons learnt which have implications for schistosomiasis control globally.
Assuntos
Anti-Helmínticos/uso terapêutico , Controle de Doenças Transmissíveis/métodos , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Tratamento Farmacológico/métodos , Humanos , Filipinas/epidemiologia , Esquistossomose/tratamento farmacológicoRESUMO
Schistosomiasis is a neglected tropical disease that ranks second only to malaria in terms of human suffering in the tropics and subtropics. Five species are known to infect man and there are currently over 240 million people infected worldwide. The cornerstone of control to date has been mass drug administration with 40 mg/kg of praziquantel but there are problems with this approach. Human and bovine vaccines are in various stages of development. Integrated control, targeting the life cycle, is the only approach that will lead to sustainability and future elimination.
RESUMO
Diagnosis of schistosomiasis is made by demonstration of the parasite ova in stools, urine,and biopsy specimens from affected organs, or presence of antibodies to the different stages of the parasite or antigens circulating in body fluids by serologic techniques. DNA of schistosomes can now also be detected in serum and stool specimens by molecular technique.However, these tests are unable to determine the severity of target organ pathology and resultant complications. Accurate assessment of schistosome-induced morbidities is now made with the use of imaging techniques like ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI). US has made major contributions in the diagnosis of hepatosplenic and urinary form of disease. This imaging method provides real time results, is portable (can be carried to the bed side and the field) and is lower in cost than other imaging techniques. Typical findings in hepatosplenic schistosomiasis by US include: hyperechoic fibrotic bands along the portal vessels (Symmer's fibrosis), reduction in the size of the right lobe, hypertrophy of the left lobe, splenomegaly, and ascites. More advanced ultrasound equipment like the colour Doppler ultrasound can characterize portal vein perfusion, a procedure that is critical for the prediction of disease prognosis and for treatment options for complicated portal hypertension. Although CT and MRI are more expensive, are hospital based, and require highly additional specially-trained personnel, they provide more accurate description of the pathology, not only in hepatosplenic and urinary forms of schistosomiasis, but also in the diagnosis of ectopic forms of the disease,particularly involving thebrain and spinal cord. MRI demonstrates better tissue differentiation and lack of exposure to ionizing radiation compared with CT.
RESUMO
Schistosomiasis is a chronic enteropathogenic disease caused by blood flukes of the genus Schistosoma. The disease afflicts approximately 240 million individuals globally, causing approximately 70 million disability-adjusted life years lost. Chronic infections with morbidity and mortality occur as a result of granuloma formation in the intestine, liver, or in the case of Schistosoma haematobium, the bladder. Various methods are utilized to diagnose and evaluate liver fibrosis due to schistosomiasis. Liver biopsy is still considered the gold standard, but it is invasive. Diagnostic imaging has proven to be an invaluable method in assessing hepatic morbidity in the hospital setting, but has practical limitations in the field. The potential of non-invasive biological markers, serum antibodies, cytokines, and circulating host microRNAs to diagnose hepatic fibrosis is presently undergoing evaluation. This review provides an update on the recent advances made with respect to gastrointestinal disease associated with chronic schistosomiasis.
Assuntos
Esquistossomose/diagnóstico , Esquistossomose/parasitologia , Animais , Biomarcadores/sangue , Doença Crônica , Citocinas/sangue , Humanos , Cirrose Hepática/imunologia , Cirrose Hepática/parasitologia , Cirrose Hepática/patologia , Morbidade , Schistosoma/crescimento & desenvolvimento , Esquistossomose/patologiaRESUMO
Schistosomiasis japonica has a long history in the Philippines. In 1975, 24 endemic provinces were identified in the northern, central, and southern islands of the Philippines. More than five million people were at risk, with approximately one million infected. In 2003, new foci of infection were found in two provinces in the north and central areas. For the past 30 years, human mass drug administration (MDA), utilizing the drug praziquantel, has been the mainstay of control in the country. Recent studies have shown that the schistosomiasis prevalence ranges from 1% to 50% within different endemic zones. Severe end-organ morbidity is still present in many endemic areas, particularly in remote villages with poor treatment coverage. Moreover, subtle morbidities such as growth retardation, malnutrition, anemia, and poor cognitive function in infected children persist. There is now strong evidence that large mammals (e.g. water buffaloes, cattle) contribute significantly to disease transmission, complicating control efforts. Given the zoonotic nature of schistosomiasis in the Philippines, it is evident that the incidence, prevalence, and morbidity of the disease will not be controlled by MDA alone. There is a need for innovative cost-effective strategies to control schistosomiasis in the long term.