Molecular assay and in vitro culture for Blastocystis prevalence in Dakahlia governorate, Egypt.

Blastocystis is a polymorphic enteric parasite with a worldwide distribution. It is one of the most common human intestinal protozoans in developing countries. The primary objective of this study was to determine the diagnostic value of microscopy, stool culture, and a polymerase chain reaction (PCR) technique for assessment of Blastocystis prevalence and risk factors. Human stool samples were collected from 110 individuals from Dakahlia governorate, Egypt as a part of a routine check-up or having gastrointestinal tract (GIT) symptoms. These samples were subjected to direct fecal smear microscopy, culture, and PCR for the detection of Blastocystis sp. Positive results for Blastocystis screening among the study population were 36 (32.7%), 41 (37.3%), and 43 (39.1%) by microscopy, PCR, and culture, respectively. Statistical analyses demonstrated that the agreement between the culture and PCR was perfect (Κ=0.925). Compared to culture, the sensitivity of PCR was 95% and the specificity was 97% while the sensitivity of microscopy was 84% and the specificity was 90.5%. We concluded that the in vitro culture and molecular assay have significant diagnostic value for the accurate detection and identification of Blastocystis in stool samples. The pathogenic potential of Blastocystis cannot be ruled out because our results found a link between Blastocystis carriage and gastrointestinal symptoms.

Conjugated silver nanoparticles as a diagnostic tool for circulating hydatid antigens.

Cystic hydatid disease is one of the most significant worldwide zoonotic diseases. The causative agent is the larval stage of Echinococcus granulosus. The diagnosis of cystic echinococcosis by clinical symptoms and scanning alone is often difficult and confusing. The definite diagnosis needs sensitive and reliable serological tests. This study aimed to evaluate a nano silver-based enzyme linked immunosorbent assay (ELISA) in the detection of circulating hydatid antigen in human serum samples. The study included 66 human serum samples (36 hydatidosis confirmed cases, 15 cases infected with other parasites, and 15 normal subjects as negative control). The circulating protoscolices antigen was assayed by the nano-silver dot ELISA, nano-silver sandwich ELISA and the traditional methods (dot ELISA and sandwich ELISA). Our study revealed that the sensitivity and specificity of the nano-silver dot ELISA were 97.2% and 93.3%, respectively. The sensitivity and specificity of nano-silver sandwich ELISA were 94.4% and 96.7% respectively. The nano-silver-based ELISA showed higher sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy than the traditional ELISA. In conclusion, the nano-silver-based ELISA can be proposed as a confirmatory test in the diagnosis of cystic echinococcosis.

External and intestinal parasites of pet dogs with reference to zoonotic toxocariasis.

Examination of 3000 pet dogs over two years at the Veterinary Teaching Hospital, Faculty of Veterinary Medicine revealed external and internal parasites. The external parasites were Rhipicephalus sanguineus, Ctenocephalus felis, Sarcoptes canis, and Sarcoptes scabiei. The internal parasites were Echinococcus granulosus, Dipylidium caninum, rare Heterophyes heterophyes, and Toxocara canis. Toxocara eggs were detected in 9.83%. The results were discussed with reference to zoonotic toxocariasis.

Kinetics of eosinophilia and IgE production in experimental murine toxocariasis.

Eosinophilia and immunoglobulin E (IgE) antibody are considered the first and important elements in host responses to helminth infection. Toxocara canis, which elicits prominent eosinophilia and IgE production in normal mice, may be useful in understanding the kinetics of circulating peripheral blood eosinophils and IgE antibody during infection. The onset, magnitude and duration of peripheral blood eosinophilia and total IgE production after primary T. canis infection in female outbred albino mice was investigated. Mice were either sham inoculated (controls) or were orally infected with 1000 embryonated eggs of T. canis. Patterns in leucocytic changes include significant increase in total WBC count between weeks 6 and 13 post infection (PI) with a peak on week 8 PI. Mice showed eosinophilia between weeks 2 to 17 PI with a peak on week 7. The development of eosinophilia in T. canis-infected mice was accompanied by the release of prominent level of serum IgE between weeks 2 to 21 with a peak at week 6 PI. These findings showed that eosinophilia in T. canis infected outbred mice can be T-cell dependent.

Phylogenetic evidence for recombination in SAG5 locus in Toxoplasma gondii.

The present study evaluated the hypothesis that genetic diversity in SAG5 genes was generated by recombination events. Three lines of evidence suggested that recombination occurred in SAG5 genes in T. gondii. The permutation test revealed strong signature of intragenic recombination, pairwise comparisons of nucleotide sequences of SAG5 genes revealed that SAG5A alleles have chimerical structures composed of segments derived through recombination events between different alleles, and phylogenetic trees reconstructed based on SAG5 sequences using neighbor-joining and maximum parsimony methods, showed statistically well-supported consensus clusters of T. gondii strains specific to each SAG5 gene. Topological discrepancies between trees based on the N-terminal variable domain and C-terminal conserved domain sequences, were observed, suggesting intragenic recombinetion between SAG5A and SAG5B/C genes. The results showed that recombination within SAG5 in T. gondii was a major evolutionary mechanism generating both allelic variation at SAG5 locus and contributing to genotypic diversity and to emergence of new T. gondii variants, allowing them to evade the host immune defence mechanism.

Mirazid alone or combined with Paromomycin in treating cryptosporidiosis parvum in immunocompetent hospitalized patients.

Sixty cryptosporidiosis patients from Mansoura University Hospitals, 36 males and 24 females, with age from few months to ten years (mean age 6.1) were divided into three cross-matched groups of 20 patients each. All patients received the glutamine-based oral rehydration solution with 111 mmol/l glutamine, 20 mg zinc acetate once a day and vitamin A supplementation (200,000 IU) once a day for 2 weeks. For cryptosporidiosis treatment, G1 received Mirazid (10 mg/kg for 2 weeks), G2 received Paromomycin (500 mg qid for 2 weeks), and G3 received a combination of Mirazid (10 mg/kg) and Paromomycin (500 mg) for two weeks. The result was assessed according to the scales: 0 = no improvement, 1 = symptoms began improvement (reduction of diarrhea frequency and stool volume, less abdominal pain, less nausea & vomiting), 2 = diarrhea eradication, 3 = weight gain, 4 = oocyst counts reduction, 5 = reduction in diarrhea and oocyst counts, 6 = eradication of diarrhea and oocysts. G3 showed significantly higher difference than G1 & G2 in the 1st week (p = .036, 0.025 respectively), no significant difference in 2nd week, a significantly higher difference than in G1 (0.003), & G2 (0.006) in 3rd week, and a significantly higher difference than G1 (0.014), & G2 (0.01) in 4th week, but without significant differences in oocyst shedding in the 3 groups.

Biochemical parameters in chronic fascioliasis.

Serum lipids, liver enzymes and total bile acids were measured in chronic Fasciola (cholestatic and non-cholestatic) patients. Variations in the biochemical parameters between infected and control groups were detected and typified by considerably higher serum triglycerides (TG, P < 0.001), alkaline phosphatase (ALP, P< 0.001) and total bile acids (TBA, P < 0.001) in the infected group. For cholestatic patients, TG, very low density lipoprotein (VLDL), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gammaglutamyl transferase (GGT) and ALP were statistically higher (P < 0.001 for each comparison) and total cholesterol (TC); low density lipoprotein (LDL) and high density lipoprotein (HDL), were statistically lower than non-cholestatic patients (P = 0.02, < 0.001, < 0.001 respectively). No statistically significant differences were found for the TC, HDL, VLDL, ALT, AST and GGT between non-cholestatic patients and healthy controls.