RESUMEN
The larval stages of the cestode parasites belonging to the genus Echinococcus grow within internal organs of humans and a range of animal species. The resulting diseases, collectively termed echinococcoses, include major neglected tropical diseases of humans and livestock. Echinococcus larvae are outwardly protected by the laminated layer (LL), an acellular structure that is unique to this genus. The LL is based on a fibrillar meshwork made up of mucins, which are decorated by galactose-rich O-glycans. In addition, in the species cluster termed E. granulosus sensu lato, the LL features nano-deposits of the calcium salt of myo-inositol hexakisphosphate (Insp6). The main purpose of our article is to update the immunobiology of the LL. Major recent advances in this area are (i) the demonstration of LL "debris" at the infection site and draining lymph nodes, (ii) the characterization of the decoy activity of calcium Insp6 with respect to complement, (iii) the evidence that the LL mucin carbohydrates interact specifically with a lectin receptor expressed in Kupffer cells (Clec4F), and (iv) the characterization of what appear to be receptor-independent effects of LL particles on dendritic cells and macrophages. Much information is missing on the immunology of this intriguing structure: we discuss gaps in knowledge and propose possible avenues for research.
Asunto(s)
Equinococosis , Echinococcus granulosus , Echinococcus , Animales , Calcio , Equinococosis/parasitología , Echinococcus/inmunología , Echinococcus granulosus/química , Echinococcus granulosus/inmunología , MucinasRESUMEN
The larval stages of the cestode parasites belonging to the genus Echinococcus grow within internal organs of humans and a range of animal species. The resulting diseases, collectively termed echinococcoses, include major neglected tropical diseases of humans and livestock. Echinococcus larvae are outwardly protected by the laminated layer (LL), an acellular structure that is unique to this genus. The LL is based on a fibrillar meshwork made up of mucins, which are decorated by galactose-rich O-glycans. In addition, in the species cluster termed E. granulosus sensu lato, the LL features nano-deposits of the calcium salt of myo-inositol hexakisphosphate (Insp6). The main purpose of our article is to update the immunobiology of the LL. Major recent advances in this area are (i) the demonstration of LL "debris" at the infection site and draining lymph nodes, (ii) the characterization of the decoy activity of calcium Insp6 with respect to complement, (iii) the evidence that the LL mucin carbohydrates interact specifically with a lectin receptor expressed in Kupffer cells (Clec4F), and (iv) the characterization of what appear to be receptor-independent effects of LL particles on dendritic cells and macrophages. Much information is missing on the immunology of this intriguing structure: we discuss gaps in knowledge and propose possible avenues for research.
Asunto(s)
Animales , Calcio , Equinococosis/parasitología , Echinococcus/inmunología , Echinococcus granulosus/inmunología , MucinasRESUMEN
BACKGROUND: The diagnosis of cystic echinococcosis (CE) is primarily based on imaging, while serology should be applied when imaging is inconclusive. CE cyst stage has been reported among the most important factors influencing the outcome of serodiagnosis. We performed a systematic review and meta-analysis of the relation between cyst stage of hepatic CE and diagnostic sensitivity of serological tests, to evaluate whether their relation is a consistent finding and provide guidance for the interpretation of results of serological tests. METHODOLOGY/PRINCIPAL FINDINGS: MEDLINE, EMBASE, CENTRAL, and Lilacs databases were searched on December 1st 2019. Original studies published after 2003 (year of publication of the CE cyst classification), reporting sensitivity of serological tests applied to the diagnosis of human hepatic CE, as diagnosed and staged by imaging, were included. The quality of studies was assessed using the Newcastle-Ottawa Scale. Data from 14 studies were included in the meta-analysis. Summary estimates of sensitivities and 95% confidence intervals were obtained using random effects meta-analysis. Overall, test sensitivity was highest in the presence of CE2 and CE3 (CE3a and/or CE3b), and lowest in the presence of CE5 and CE4 cysts. ELISA, ICT and WB showed the highest sensitivities, while IHA performed worst. CONCLUSIONS/SIGNIFICANCE: The results of our study confirm the presence of a clear and consistent relation between cyst stage and serological tests results. Limitations of evidence included the heterogeneity of the antigenic preparations used, which prevented to determine whether the relation between cyst stage and sensitivity was influenced by the type of antigenic preparation, the paucity of studies testing the same panel of sera with different assays, and the lack of studies assessing the performance of the same assay in both field and hospital-based settings. Our results indicate the absolute need to consider cyst staging when evaluating serological results of patients with hepatic CE.
Asunto(s)
Quistes/patología , Equinococosis Hepática/diagnóstico , Echinococcus/inmunología , Pruebas Serológicas/métodos , Animales , Anticuerpos Antihelmínticos/sangre , Equinococosis Hepática/sangre , Equinococosis Hepática/parasitología , Echinococcus/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática , Humanos , Sensibilidad y Especificidad , Factores de TiempoRESUMEN
Objective: Cystic echinococcosis (CE) is a common public health concern in Turkey. In this study, we investigated the agreement between the results of radiological imaging methods and serological tests through a 5-year retrospective evaluation in patients admitted to a university hospital with a suspicion of CE so as to determine the frequency of CE in the study region. Methods: The indirect hemagglutination test (IHA) results of 1.046 patients obtained from various clinics with the suspicion of CE between January 2014 and December 2018 were retrospectively analysed. Of these, patients with at least one radiological imaging report in the system (938 patients) were included in the study. Radiological imaging findings and IHA test results were compared and examined. Results: Seropositivity was detected by IHA test in 143 (15.2%) of 938 patients included in the study. The CE findings were recorded in at least one radiological imaging report in 130 (90.9%) of 143 patients with positive IHA test. At least one of the radiological imaging reports suggested presence of CE in 362 (38.5%) of all the patients. Conclusion: Thus, serological test and radiological imaging methods should be used in combination for the diagnosis of CE.
Asunto(s)
Equinococosis/diagnóstico , Animales , Equinococosis/diagnóstico por imagen , Echinococcus/inmunología , Echinococcus/aislamiento & purificación , Pruebas de Hemaglutinación , Hospitales Universitarios , Humanos , Radiografía , Estudios Retrospectivos , Turquía/epidemiologíaRESUMEN
OBJECTIVE: To evaluate the efficiency of three Chinese commercial anti-Echinococcus antibody-based assays for the serodiagnosis of echinococcosis. METHODS: A total of 142 sera from cystic echinococcosis patients, 89 sera from alveolar echinococcosis and 39 sera from healthy controls were sampled, and detected by kits A (ELISA), B (ELISA) and C (colloidal gold immunoassay). The routine blood testing results and biochemical parameters were compared between the cystic and alveolar echinococcosis patients, and the associations of the absorbance (A value) of the serum specific antibody detected by A and B kits with the routine blood testing results and biochemical parameters were examined in echinococcosis patients. In addition, the performance of these three assays for the serodiagnosis of echinococcosis was evaluated. RESULTS: There were no significant differences between the cystic and alveolar echinococcosis patients in terms of the median white blood cell count (WBC), neutrophil count (NEU), monocyte count (MONO), basophil count (BASO), alanine aminotransferase concentration (ALT), aspirate aminotransferase concentration (AST), total bilirubin (TBIL), direct bilirubin (DBIL), indirect bilirubin (IBIL) (all P values > 0.05), and higher median lymphocyte count (LYM) and albumin levels (ALB) were detected in cystic echinococcosis patients than in alveolar echinococcosis patients (both P values < 0.05), while the median eosinophil count (EOS) was greater in the alveolar echinococcosis patients than in the cystic echinococcosis patients (P < 0.01). The A value of the serum specific antibody detected by kit A showed a linear positive correlation with WBC (rs = 0.153, P < 0.05) and EOS (rs = 0.174, P < 0.05), and a linear negative correlation with TBIL (rs = -0.134, P < 0.05) and IBIL (rs = -0.146, P < 0.05), while the A value of the serum specific antibody detected by kit B showed a linear positive correlation with WBC (rs = 0.257, P < 0.01), NEU (rs = 0.203, P < 0.01), MONO (rs = 0.159, P < 0.05), EOS (rs = 0.330, P < 0.01), ALT (rs = 0.171, P < 0.01) and AST (rs = 0.160, P < 0.05), and a linear negative correlation with ALB (rs = -0.168, P < 0.05). The overall coincidence rate, sensitivity, specificity, Youden's index and Kappa value of A, B and C kits were 86.30%, 69.63% and 91.48%; 84.42%, 64.94% and 92.21%; 97.44%, 97.44% and 87.18%; 0.82, 0.62 and 0.79; and 0.600, 0.337 and 0.750 for the diagnosis of echinococcosis, respectively. The overall coincidence rate, sensitivity, specificity and Youden's index of A, B and C kits were 84.54%, 64.64% and 71.82%; 80.99%, 55.63% and 68.31%; 97.44%, 97.44% and 87.18%; and 0.78, 0.53 and 0.56 for the diagnosis of cystic echinococcosis, respectively, while the overall coincidence rate, sensitivity, specificity and Youden's index of A, B and C kits were 92.19%, 85.16% and 85.16%; 89.89%, 79.78% and 84.27%; 97.44%, 97.44% and 87.18%; and 0.87, 0.77 and 0.72 for the diagnosis of alveolar echinococcosis, respectively. The C kit showed cross-reactions in the serodiagnosis of cystic echinococcosis and alveolar echinococcosis. There were no significant difference in the area under the receiver operating characteristic curve (ROC) between A and B kits for the diagnosis of echinococcosis (0.970 vs. 0.948, Z = 1.618, P > 0.05), and there was a high agreement between A and B kits in the diagnosis of echinococcosis (Kappa = 0.585, P < 0.01). CONCLUSIONS: The three commercial anti-Echinococcus antibody-based kits exhibit a higher serodiagnostic efficiency for alveolar echinococcosis than for cystic echinococcosis. The A kit shows a high sensitivity and specificity for the diagnosis of echinococcosis, and has a relatively stable diagnostic performance and fewer influencing factors, which is suitable for the pre-surgical preliminary diagnosis and post-surgical follow-up monitoring of serum anti-Echinococcus antibody, while the C kit shows a high sensitivity and specificity for the diagnosis of echinococcosis, and is easy to perform and high in reporting rate, which is feasible for initial screening of echinococcosis.
Asunto(s)
Anticuerpos Antihelmínticos/análisis , Equinococosis/diagnóstico , Pruebas Serológicas , Animales , Antígenos Helmínticos , Estudios de Casos y Controles , Echinococcus/inmunología , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoensayo , Sensibilidad y EspecificidadRESUMEN
Objective: To determine the results of radiological and serological screenings in individuals who shared the same living space as patients with hydatid cyst in a State Hospital of Afghanistan. Methods: Patients presenting with hydatid cyst to a public hospital in Afghanistan were included in this study. Full sampling method was used. Also, the relatives of the patients were called to the hospital and investigated for the presence of hydatid cyst antibodies through direct chest X-ray, upper abdominal ultrasonography and ELISA. Results: During the study period, a total of 214 patients, including 102 male and 112 female, underwent radiological and serological screenings. While cysts were radiologically detected in the liver, lung and spleen in 8, 2 and 1 patient, respectively, the serology was positive in 22 patients. Conclusion: As a result of the study, it was concluded that the patients who shared the same environment as the patients who were diagnosed with hydatid cyst in an endemic region for cyst hydatid disease.
Asunto(s)
Equinococosis/epidemiología , Echinococcus/aislamiento & purificación , Adolescente , Adulto , Afganistán/epidemiología , Animales , Anticuerpos Antihelmínticos/sangre , Niño , Equinococosis/sangre , Equinococosis/diagnóstico , Equinococosis/diagnóstico por imagen , Echinococcus/inmunología , Ensayo de Inmunoadsorción Enzimática , Composición Familiar , Femenino , Hospitales Provinciales , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Ultrasonografía , Adulto JovenAsunto(s)
Equinococosis Pulmonar , Pulmón/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Animales , Anticuerpos Antihelmínticos/aislamiento & purificación , Tos/fisiopatología , Equinococosis Pulmonar/diagnóstico , Equinococosis Pulmonar/fisiopatología , Equinococosis Pulmonar/terapia , Echinococcus/inmunología , Echinococcus/aislamiento & purificación , Femenino , Humanos , Remisión Espontánea , Pruebas Serológicas/métodosRESUMEN
The aims of this study were an establishment of the domestic rabbit as an intermediate host for cystic echinococcosis (CE) and to evaluate the potency of the crude germinal layer and the protoscoleces antigens to protect against the CE. Firstly; Two groups of white Newzeland rabbits were infected orally either by 5000 active oncospheres or viable protoscoleces separately. After 20 weeks, the slaughtered rabbits showed the presence of hydatid cysts at different internal organs. Molecular detection of the resulted cysts was conducted. Secondly; 27 rabbits were divided into nine groups (nâ¯=â¯3). Groups 1 and 2 were immunized with the crude germinal layer antigen while the groups 3 and 4 were immunized with the crude protoscoleces antigen. Groups 5 and 6 received the adjuvant mineral oil. Groups 7 and 8 were used as positive control. The last 9 group was kept as a negative control. The obtained results showed a significant high protection percentage of 83.4% and high antibody titer was recorded in groups that received the crude germinal layer antigen comparing with the groups that immunized with the crude protoscoleces antigen as their protection percentage was 66.7% with lower IgG response. In conclusion, the domestic rabbits could be used as a laboratory model for CE. Developing of the germinal layer antigen is more immunogenic than the protoscoleces one and could be used as a promising vaccine. Attention should be directed towards the existing rabbit in the environment adjacent to infected dogs as it could be a part of Echinococcus life cycle.
Asunto(s)
Modelos Animales de Enfermedad , Equinococosis/prevención & control , Echinococcus/inmunología , Conejos , Vacunación , Vacunas , Análisis de Varianza , Animales , Antígenos Helmínticos/inmunología , ADN de Helmintos/aislamiento & purificación , Perros , Echinococcus/genética , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina G/biosíntesis , Riñón/parasitología , Hígado/parasitología , Pulmón/parasitología , Masculino , Epiplón/parasitología , Potencia de la VacunaRESUMEN
Objective: Alveolar echinococcosis (AE) is one of the most lethal parasitic zoonoses in the Northern Hemisphere, and early serological detection is important to start treatment and to improve survival. A total of 50 sera samples of patients diagnosed as having various diseases were examined for by two different serological diagnostic methods. Methods: Em2-Em18 ELISA (Bordier Affinity Products, Crissier, Switzerland) and Echinococcus Western Blot immünoglobulin G (IgG) (LDBIO Diagnostics, Lyon, France) were used for analyisis. Results: A high titer of antibodies was found in 9 of 10 patients diagnosed as having AE with Em2-Em18 ELISA, in 2 of 21 patients with cystic echinococcosis, in 1 of 2 patients with fascioliasis and in 1 patient with chronic hepatitis. The Echinococcus Western Blot IgG test, used as a confirmatory test, showed IgG antibody in 85.7% (18/21) of patients with CE, while all serum samples of 10 patients with AE were evaluated as positive. This method yielded an incorrect diagnosis in the patient with chronic hepatitis and in the patient with granulomatous inflammation with caseification. Samples taken from patients with liver-related diseases and other parasitic-related diseases were found to be negative. Conclusion: The serological methods used in the study were found to be important in the early diagnosis of alveolar echinococcosis in the endemic areas, since it could be used in sero-epidemiological studies.
Asunto(s)
Anticuerpos Antihelmínticos/sangre , Antígenos Helmínticos/inmunología , Equinococosis/diagnóstico , Echinococcus/inmunología , Inmunoglobulina G/sangre , Adulto , Animales , Western Blotting/métodos , Diagnóstico Diferencial , Equinococosis Hepática/diagnóstico , Ensayo de Inmunoadsorción Enzimática/métodos , Fascioliasis/diagnóstico , Femenino , Proteínas del Helminto/inmunología , Hepatitis Crónica/diagnóstico , Humanos , MasculinoRESUMEN
Cystic echinococcosis (CE) in sheep is a hazardous zoonotic parasitic disease that is caused by Echinococcus granulosus (Eg). At present, serological test is an important diagnostic method for Eg infection in domestic animals. Here, a fusion protein Eg mefAg-1 harboring 8 dominant B-cell epitopes of Eg such as antigen B, tetraspanin 1, tetraspanin 6, reticulon and Eg95 was produced in E. coli and evaluated for CE in sheep by indirect ELISA. Eg mefAg-1 showed in ELISA a high sensitivity (93.41%) and specificity (99.31%), with a coincidence rate of 97.02%. Overall, it is suggested that the Eg mefAg-1 could be a potential antigen candidate for CE serodiagnosis in sheep.
Asunto(s)
Anticuerpos Antihelmínticos/sangre , Antígenos Helmínticos/inmunología , Equinococosis/veterinaria , Echinococcus/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática/métodos , Pruebas Serológicas/métodos , Enfermedades de las Ovejas/diagnóstico , Animales , Antígenos Helmínticos/genética , Equinococosis/diagnóstico , Equinococosis/parasitología , Echinococcus/inmunología , Epítopos/genética , Epítopos/inmunología , Escherichia coli/genética , Escherichia coli/metabolismo , Incidencia , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Sensibilidad y Especificidad , Ovinos , Enfermedades de las Ovejas/parasitologíaAsunto(s)
Equinococosis/diagnóstico , Equinococosis/parasitología , Enfermedades Peritoneales/diagnóstico , Adolescente , Animales , Anticuerpos Antihelmínticos/análisis , Diagnóstico Diferencial , Equinococosis/cirugía , Echinococcus/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Enfermedades Peritoneales/parasitología , Enfermedades Peritoneales/cirugía , Espacio Retroperitoneal , Tomografía Computarizada por Rayos XRESUMEN
Cystic echinococcosis (CE) is a neglected zoonotic disease with a worldwide distribution and is a major public health problem in some areas. Diagnosis of CE is mainly based on clinical symptoms, imaging and serological testing, however, improvement in serodiagnosis is still needed. This study was aimed at detecting circulating Echinococcus antigen in CE patients using a lateral flow dipstick (LFD) assay. Three types of hydatid antigens i.e. hydatid cyst fluid (HCF), native antigen B (nAgB) and recombinant antigen B (rAgB) were prepared and polyclonal rabbit antiserum was raised against each antigen. Purified IgG fractions were prepared and a portion was conjugated to gold nanoparticles. After a series of optimizations, a final antigen detection LFD assay was developed using a combination of anti-nAgB-IgG and gold-conjugated anti-HCF-IgG. Evaluation of the assay showed that 27 out of 35 (77%) serum samples from CE patients gave positive results. Meanwhile, the test showed a diagnostic specificity of 82% when tested with sera from 38 healthy individuals and 13 patients with other parasitic diseases. In conclusion, the antigen detection LFD assay seemed to be useful for diagnosis of CE and possibly for post-treatment follow-up, and merit further evaluation studies. We foresee that it may improve serodiagnosis of CE when used in tandem with an antibody detection test.
Asunto(s)
Equinococosis/sangre , Equinococosis/diagnóstico , Echinococcus/inmunología , Proteínas del Helminto/sangre , Lipoproteínas/sangre , Pruebas Serológicas/métodos , Adolescente , Adulto , Anciano , Animales , Anticuerpos Antihelmínticos/inmunología , Niño , Líquido Quístico/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Proteínas del Helminto/inmunología , Humanos , Lipoproteínas/inmunología , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Adulto JovenRESUMEN
Background: Cystic echinococcosis (CE) is a helminthic disease caused by the larval form of Echinococcus granulosus. In the present study, the B8/2 subunit of antigen B (AgB) of E. granulosus was expressed in E. coli host and then applied in a diagnostic ELISA set up. Methods: The DNA sequence of AgB8/2 subunit from E. granulosus was extracted from the GenBank and codon-optimized according to E. coli codon usage. The target sequence was cloned in an expression vector (pGEX-4T-1). The produced antigen was used in an ELISA system, and its performance for the diagnosis of human hydatid cyst was evaluated, using sera from CE and non-CE patients, along with the sera from healthy subjects. Moreover, the diagnostic value of the recombinant protein was compared with native AgB, as well as with a commercial kit. Results: Antibodies to hydatid cyst were detected in 27 out of 30 patients corresponding to a sensitivity of 90% (95% CI: 73-98%). Cross-reaction with sera of non-CE subjects was seen in two cases resulted in a specificity of 93.5% (95% CI: 82-98%) for the test. A sensitivity of 87% and specificity of 90% were found for the native form of the antigen, while the ELISA commercial kit had a sensitivity of 97% and specificity of 95%. Conclusion: Our data show that rEgAgB8/2 is an appropriate source of antigen for the serological diagnosis of human hydatid cyst. Co-expression of the rEgAgB/2 along with other subunits of AgB may enhance the performances of these antigens for the serodiagnosis of human CE.
Asunto(s)
Antígenos Helmínticos/inmunología , Equinococosis/diagnóstico , Equinococosis/parasitología , Echinococcus/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Subunidades de Proteína/metabolismo , Juego de Reactivos para Diagnóstico , Proteínas Recombinantes/metabolismo , Animales , Antígenos Helmínticos/biosíntesis , Equinococosis/inmunología , Humanos , Subunidades de Proteína/biosíntesis , Subunidades de Proteína/aislamiento & purificación , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/aislamiento & purificaciónRESUMEN
OBJECTIVE: The aim of this study was to retrospectively evaluate the serological and radiological analysis and medical and surgical treatment results of patients diagnosed with cystic echinococcosis (CE). METHODS: Records belonging to a total of 67 patients diagnosed with CE who presented to the Kars Kafkas University Faculty of Medicine Research Hospital's Surgical Outpatient unit between January 2012 and December 2015 were retrospectively evaluated. RESULTS: Of 67 CE cases, 53 (79.1%) were females and 14 (20.9%) were males. The age ranged between 12 and 77 years, and the mean age was 47.37±17.81 years. The most common cyst location was the liver, in 60 patients (89.5%). Other localizations were found in 7 (10.5%) of the 67 cases. Open surgery was used to treat 32, and drainage accompanied by ultrasonography (USG) was used to treat 13 cystic cases. The remaining 22 patients were followed-up. Among the followed-up patients, the radiologic imaging findings of six patients were consistent with a hydatid cyst, but the indirect hemagglutination assay (IHA) results were negative. CONCLUSION: We concluded that CE is an important public health problem for the Kars region due to a low socioeconomic and educational level, where livestock breeding is also common. More comprehensive epidemiological studies should be undertaken and national control programs are required to keep the disease under control.
Asunto(s)
Equinococosis/epidemiología , Pacientes Ambulatorios , Adolescente , Adulto , Anciano , Animales , Niño , Equinococosis/diagnóstico , Equinococosis/diagnóstico por imagen , Echinococcus/inmunología , Femenino , Pruebas de Hemaglutinación , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Turquía/epidemiología , Ultrasonografía , Adulto JovenRESUMEN
BACKGROUND: As part of an ongoing program that aims to use early detection and timely treatment to improve the control of echinococcosis, especially in younger age groups, we undertook a series of active surveys among Qinghai-Tibetan children in the Qinghai Province of Northwestern China in 2011 and 2012. The significant outcomes that resulted from this study emphasize the need to draw attention to echinococcosis, both alveolar echinococcosis (AE) and cystic echinococcosis (CE), so that policy development is promoted and suitable avenues for control are identified in the highly endemic areas on the Tibetan Plateau. METHODS: A total of 19 629 primary school students, aged 6-18 years, with a dominant Tibetan background underwent abdominal ultrasound examination, and 86.4% of the compliant students donated 2-5 ml of venous blood for serological tests. All the abnormal ultrasound results were recorded. If identified as echinococcosis, the disease lesion was assessed according to the WHO-Informal Working Group on Echinococcosis (WHO-IWGE) classification for AE and CE. Among the surveyed students, the prevalence by school was compared among geo-locations, sex and age groups. The clinical image presentations were analyzed according to lesion number, size, the location in the liver and the classification stage. Statistical significance was set at P-value < 0.05 for comparisons among groups. RESULTS: A total of 341 students (1.7%) were identified by ultrasound as having either CE (119, 0.6%) or AE (222, 1.1%). The highest prevalence rates of childhood AE cases occurred in the Tehetu (12.1%) and Moba (11.8%) townships in Dari County. There was a high seropositive rate (37.0%) and a heterogeneous distribution of cases, with a prevalence ranged from 0 to 12.1% for AE and 0-2.9% for CE. Moreover, the seropositive rate ranged from 0.7-45.1% across different schools. CONCLUSIONS: The high prevalence of echinococcosis in Qinghai-Tibetan primary school students reflects a lack of knowledge about Echinococcus spp. transmission. The combination of systematic education for children and regularly performed anthelmintic treatment for dogs could achieve the goal of sustainable hydatidosis control.
Asunto(s)
Equinococosis/epidemiología , Adolescente , Animales , Anticuerpos Antihelmínticos/sangre , Niño , Equinococosis/sangre , Equinococosis/diagnóstico , Equinococosis/parasitología , Echinococcus/inmunología , Echinococcus/fisiología , Enfermedades Endémicas/estadística & datos numéricos , Femenino , Humanos , Masculino , Prevalencia , Instituciones Académicas/estadística & datos numéricos , Estudiantes/estadística & datos numéricos , Tibet/epidemiologíaRESUMEN
The present preliminary study intends to evaluate the in vitro use of hydatid antigen and their antibodies once labeled with iodine 125(I125) and characterized from viewpoint of radiochemical purity and immunoreactivity. Radiolabelled molecules gave satisfactory purity of 94% and 96%-98%, for hydatid antigen and IgG respectively. As regards, the specific activity of these latter, varied between 4.79 and 5.97⯵Ci/µg. The specificity test of radiolabelled IgG against the hydatid membranes showed a significant recognition that increased proportionally according to the contact surface. Likewise this immunoreactivity test performed with a simple binding assay, using human hydatid fluid antigen (HHF-Ag), previously fixed on a solid phase, gave satisfactory fixation rate of the order of 356⯱â¯48.08cpm, 2539⯱â¯550.12cpm and 6558⯱â¯712.76cpm for the concentrations of 0.1⯵g/ml, 2⯵g/ml and 25⯵g/ml respectively. Statistical study of 88 sera, carried out with radiolabelled antigen (125I-HHF-Ag) in competitive radioimmunoassay test (CRIA) showed highly significant difference (pâ¯<â¯0.0001) in the binding capacity of antigens from patients sera with hydatid disease (65.63⯱â¯9.12) compared to the negative sera (19.25⯱â¯14.84). No cross reaction was observed using sera from patients with toxoplasmosis (33, 07⯱â¯13, 07) and the difference was highly significant (pâ¯<â¯0.0001) compared to E granulosus infected patient sera. Furthermore, this test seemed to be sensitive since among the 43 sera tested, only 37 (86%) were found to be positive by passive hemagglutination (HAP), while the totality (100%) responded positively by CRIA. Our findings are encouraging, suggesting that these radiolabeled molecules could be useful for advancing toward new diagnostic and therapeutic modalities.
Asunto(s)
Anticuerpos Antihelmínticos/inmunología , Antígenos Helmínticos/inmunología , Equinococosis/diagnóstico , Echinococcus/inmunología , Animales , Cromatografía en Gel , Equinococosis/inmunología , Electroforesis en Gel de Poliacrilamida , Pruebas de Inhibición de Hemaglutinación , Humanos , Inmunodifusión , Inmunoelectroforesis , Inmunoglobulina G/inmunología , Inmunoglobulina G/aislamiento & purificación , Trazadores Radiactivos , RadioinmunoensayoRESUMEN
Granulomas are responses to persistent nonliving bodies or pathogens, centrally featuring specialized macrophage forms called epithelioid and multinucleated giant cells. The larval stages of the cestode parasites of the Taeniidae family (Taenia, Echinococcus) develop for years in fixed tissue sites in mammals. In consequence, they are targets of granulomatous responses. The information on tissue responses to larval taeniids is fragmented among host and parasite species and scattered over many decades. We attempt to draw an integrated picture of these responses in solid tissues. The intensity of inflammation around live parasites spans a spectrum from minimal to high, parasite vitality correlating with low inflammation. The low end of the inflammatory spectrum features collagen capsules proximal to the parasites and moderate distal infiltration. The middle of the spectrum is dominated by classical granulomatous responses, whereas the high end features massive eosinophil invasions. Across the range of parasite species, much observational evidence suggests that eosinophils are highly effective at killing larval taeniids in solid tissues, before and during chronic granulomatous responses. The evidence available also suggests that these parasites are adapted to inhibit host granulomatous responses, in part through the exacerbation of host regulatory mechanisms including regulatory T cells and TGF-ß.
Asunto(s)
Equinococosis/patología , Echinococcus/inmunología , Granuloma/parasitología , Larva/inmunología , Taenia/inmunología , Teniasis/patología , Animales , Equinococosis/parasitología , Eosinófilos/inmunología , Granuloma/inmunología , Inflamación/parasitología , Macrófagos/inmunología , Mamíferos/parasitología , Linfocitos T Reguladores/inmunología , Teniasis/parasitologíaRESUMEN
Cystic echinococcosis (CE) is a parasitic zoonosis especially affecting resource-poor populations in livestock raising areas. Imaging, in particular ultrasound (US), is crucial for the diagnosis, staging, and clinical management of abdominal CE in humans. Serology is a valuable complement to imaging, especially when ultrasound features of CE are absent or unclear. In rural endemic areas, where expertise in US is scant, and conventional serology techniques are unavailable due to lack of laboratory equipment, rapid diagnostic tests (RDTs) may be very useful. Several reports have described the performance of commercial and experimental RDTs in the diagnosis of CE, including a recent study by our group that compared the diagnostic performances of three commercial RDTs for the diagnosis of hepatic CE. To put RDTs for CE in context, we reviewed the available literature in English on this topic. Overall, RDTs appear to be useful in resourcepoor settings where they may replace conventional serodiagnostic tests. However, like other serodiagnostic tests, RDTs lack standardization and show unsatisfactory sensitivity and specificity. An important issue that needs to be addressed is that studies on the diagnostic performance of RDTs fail to take into account the variables known to influence results such as anatomical location and cyst stage.
Asunto(s)
Pruebas Diagnósticas de Rutina/métodos , Equinococosis/diagnóstico , Pruebas Serológicas/métodos , Animales , Anticuerpos Antihelmínticos/sangre , Equinococosis/sangre , Echinococcus/inmunología , Ensayo de Inmunoadsorción Enzimática , Humanos , Sensibilidad y Especificidad , Factores de TiempoRESUMEN
Among the species composing the genus Echinococcus, four species are of human clinical interest. The most prevalent species are Echinococcus granulosus and Echinococcus multilocularis, followed by Echinococcus vogeli and Echinococcus oligarthrus. The first two species cause cystic echinococcosis (CE) and alveolar echinococcosis (AE) respectively. Both diseases have a complex clinical management, in which laboratory diagnosis could be an adjunctive to the imaging techniques. To date, several approaches have been described for the laboratory diagnosis and followup of CE and AE, including antibody, antigen and cytokine detection. All of these approaches are far from being optimal as adjunctive diagnosis particularly for CE, since they do not reach enough sensitivity and/or specificity. A combination of several methods (e.g., antibody and antigen detection) or of several (recombinant) antigens could improve the performance of the adjunctive laboratory methods, although the complexity of echinococcosis and heterogeneity of clinical cases make necessary a deep understanding of the host-parasite relationships and the parasite phenotype at different developmental stages to reach the best diagnostic tool and to make it accepted in clinical practice. Standardization approaches and a deep understanding of the performance of each of the available antigens in the diagnosis of echinococcosis for the different clinical pictures are also needed. The detection of the parasite in definitive hosts is also reviewed in this chapter. Finally, the different methods for the detection of parasite DNA in different analytes and matrices are also reviewed.