Identification and immunological characterization of Echinostoma liei antigens: preliminary study for validation of its use in schistosomiasis control program

Several studies have proposed the use of larvae of Echinostoma in schistosomiasis biological control program, since Echinostoma rediae attack and even destroy S. mansoni sporocysts probably by induction of host's inflammatory response when they are in the same molluscan. The objective of the present work was to identify and immunologically characterize E. liei antigens to be presented as a promising tool in schistosomiasis control program. Two E. liei antigens were prepared namely metacercarial and adult worm antigens in addition to Schistosoma soluble egg antigen [SEA] and Schistosoma worm antigen [SWAP]. Analysis of the four antigens by sodium dodecyl sulphate polyacrylamide gel electrophoresis [SDS-PAGE] revealed a number of bands except for the metacercarial antigen of E. liei which appeared as a single band. Immunoblotting revealed three common bands between SEA, SWAP and E. liei worm antigen corresponding to 17, 29 and 97 kDa. Detection of specific total IgG and IgG4 isotype in sera of S. mansoni infected patients were measured by ELISA using all four studied antigens. The levels of both IgG and IG4 isotype showed no statistical significant difference between schistosomal SEA, SWAP and worm E. liei antigens. On the other hand, metacercarial antigen revealed statistically significant lower levels of both IgG and IgG4 when compared with schistosomal SEA [p< 0.05]. The highest sensitivity and specificity rates for detection of specific total IgG and IgG4 isotype were recorded when using schistosomal SEA. Owing to its rather promising results, further studies are needed to investigate the possible validity of using E. liei adult worm antigen in snail immunization against schistosomiasis especially in endemic areas where re-infection is commonly encountered

Detection of Fasciola Antigen in Serum and Stool Samples

Fascioliasis as a zoonotic disease that affects humans is more important than previously thought especially in endemic areas .This work estimates immunodiagnosis of Fasciola by detecting both circulating and copro-antigens. Rabbit anti-cysteine protease was prepared and used for antigen capture and detection by sandwich EUSA. Fasciola antigen detection in sera of naturally infected animals revealed high sensitivity [87.75%] and specificity [94.38%]. Copro antigen detection in stool of naturally infected animals yielded 93.19% sensitivity and 96.62% specificity respectively. A pilot application of both assays was performed for a sample of subjects. The sandwich ELISA detected antigen in sera of Fasciola patients with 92.4% sensitivity and 94.7% specificity. The sandwich ELISA achieved high sensitivity [100%] and specificity [90.63%] for coproantigen detection. Detection of Fasciola antigen in stool could be introduced as cost effective, non invasive standard assay for the screen diagnosis of Fasciola in humans living in endemic areas. These assays may be promising for inimunodiagnosis of fascioliasis that could be complementary tool to parasitological examination

Epidemiologic approach for early detection and control of renal and urinary tract diseases in rural populations

The dipstick testing, microscopic examination of urine and urine cytology were performed for inhabitants from two rural villages [El Shobak El Sharki, V.I and El Katta, V.2] in Giza G. The proliferating cell nuclear antigen [PCNA] and Schistosoma haematobium antigen were done by immuno-histochemical stain to confirm diagnosis. Also, they were subjected to medical questionnaire, clinical examination, ultra-sonography of kidneys and urinary tract. The results showed that V.2 had higher percentage of haematuria, proteinuria, glucosuria and lower urinary tract infection than V.I. Crystaluria was higher in V.I. Sensitivity of dipstick testing compared to microscopic examination was 26.6%, and specificity was 78.7%. Lower urinary tract infection cytologically detected was 44.2% sensitivity and 62.5% specificity compared to pyuria detected by microscopic examination of urine. Among those suffering variable urinary abnormalities, schistosome antigen was not detected in any fixed urine samples in comparison to corresponding confirmed positive controls. Urine cytology detected urinary tract infection, Crystaluria, dysplasia and atypia, squamous metaplasia and transitional cell carcinoma [TCC]. PCNA positivity was found in TCC [100%], dysplasia [50%] and squamous metaplasia [28.6%]. So, microscopic examination of urine proved valuable for tract abnormalities as pyuria, haematuria and crystaluria. Also, urine cytology is a must for malignancy of urinary tract especially in adult males

Role of secretory excretory products of Schistosoma mansoni eggs in modulating hepatic morbidity

In the present study the possible anti-morbidity effect of secretory excretory products [SEP] of Schistoma mansoni eggs [given to mice before infection] was investigated. Multiple small doses of SEP were injected intra-peritoneally into albino mice [100 micro g of purified SEP followed 2 weeks later by two booster doses of 50 micro g each at weekly intervals]. Data revealed reduction in CD4+ cells and increase in CD8+ cells of hepatic granuloma in SEP-immunized infected group, resulting in significant decrease in CD4+/CD8+ ratio, in comparison to infected control group. The serum cytokine level of both TNF--alpha and IFN-gamma were also significantly decreased. Histopathological examination of liver revealed remarkable increase in degenerated ova within hepatic granuloma which decreased in diameter [12%]. Significant reduction in worm burden [46%] and tissue egg loads [42.8% and 50% for hepatic and intestinal ova respectively] were observed. Mean while decreased percent of immature stages with increase in percent of dead ova in Oogram pattern was recorded. This work may help in decrease the severity of hepatic morbidity

Investigation of parasitic agents in diarrheic patients in a rural population

Infectious intestinal diseases are highly prevalent and diarrhea is among the commonest complaints. A cross sectional study was carried out on 56 diarrhea1 cases of El Shobak El Sharki villagers [Guiza Governorate]. The study aims at investigating the parasitic causative agents of diarrhea and comparing four different techniques for diagnosis. These were Merthiolate-Iodine-Formaldehyde [MIF] concentration technique, Modified Ziehl Neelsen [ZN] staining technique, Enzyme Imrnunoassay [EIA] and Merifluor Cryptosporidium /Giardia lmmunofluorescence Assay [IFA]. Depending on the diagnosis by the four methods together, Giardia lamblia was found in 46.4%, Cryptosporidium parvum in 37.5%, and Entamoeba histolytica in 7.1% of diarrheic cases. Comparison of the different techniques showed that IFA was superior in diagnosing C. parvum [90.5% sensitivity], while ZN stain had a sensitivity of 85.7%. The technique of EIA was not so efficient in diagnosing C. parvum [28.6% sensitivity]. As regards the diagnosis of G. lamblia, sensitivity of IFA was 84.6%, while EIA showed 65.4% sensitivity. Giardia lamblia could be diagnosed by MIF technique which showed u sensitivity of 30.8%. The four techniques showed 100% specificity with all studied protozoa. Many factors were correlated to the positive findings. Cryptosporidium parvum was found more in adult age groups than younger ones the reverse is true as regards infection with G. lamblia. Drinking water and swimming in water canals were potential sources of transmission, also finding the same parasite in members of the same family is discussed. In conclusion C. parvum represented more than one third the number of causative agents of diarrhea in rural population having diarrhea. So, health care professionals must be aware of the different diagnostic procedures plus its specific treatment. Routine stool analysis depending on MIF and modified ZN staining techniques is a cost-effective tool for screening of diarrhea. If the results are negative and parasitic agents for diarrhea could not be excluded clinically, referral should be made to reference laboratory to do Cryptosporidium/Giardia Merifluor IFA technique. If negative results are still obtained, repetition of IFA technique for successive days is recommended

Incidence of cryptosporidiosis in immunodeficient cancer patients in Egypt

A coproprotozoal study was carried out on 63 patients suffering from malignancy. The majority had cancer of the hemopoietic system. All patients were under chemotherapy and classified into two groups: Group A [33 children] and group B [30 adults], of whom 20 immunocompetent diarrheic patients of matched age and sex were considered as controls. Stool samples were examined by merthiolate iodine-formaldehyde concentration technique [MIF]. Modified Zeihl- Neelsen [ZN] stain was performed for Cryptosporidium oocysts. The detection of Cryptosporidium coproantigen by enzyme-linked immunoassay test [Ridascreen test] was used. Immunoglobulins [IgG, IgM, IgE and IgA], C3, C4 and CD4:CD8 ratio were measured. According to their levels, 25 out of 63 patients had both humoral and cellular immunodeficiency. The incidence of Cryptosporidium in cancer patients was 23.8%, while it was 37.7% and 91% in children and adults immunodeficient patients, respectively. ZN stain was able to diagnose Cryptosporidium in 13 out of 35 immunodeficient cases, while ELISA detected only 11 cases. Cryptosporidium infection in immunodeficient cancer patients had significantly more frequent and prolonged duration of diarrhea than in negative ones