Molecular, biochemical, and morphometric characterization of Fasciola species potentially causing zoonotic disease in Egypt.

Fascioliasis is an important disease caused by Fasciola hepatica and Fasciola gigantica. The distributions of both species overlap in many areas of Asia and Africa including Egypt. Fifty adult Fasciola worms were collected from livers of cattle and sheep slaughtered in abattoirs, Cairo, Egypt. They were subjected to morphological and metric assessment of external features of fresh adults, morphological and metric assessment of internal anatomy of stained mounted worms, determination of electrophorezed bands of crude adult homogenates using SDS-PAGE, and molecular characterization of species-specific DNA segments using RFLP-PCR. It was found that the correlation between conventional morphology and its morphotype was statistically significant (P value = 0.00). Using SDS-PAGE, 13 bands were detected among both genotypes of Fasciola (35.7, 33.6, 32.4, 29.3, 27.5, 26, 24.4, 23, 21.45, 19, 16.75, 12.5, and 9.1 kDa).The most prevalent bands were that with a molecular weight of 29.3, 26, and 19 kDa. Bands detected were common for both species, but protein bands could not distinguish between F. hepatica and F. gigantica. The result of PCR for the amplification of the selected 28S rDNA fragment with the designed primer set yielded 618 bp long PCR products for F. hepatica and F. gigantica. Different band patterns generated after digestion of the 618 bp segment by the enzyme AvaII obtained with F. hepatica showed segments of the length 529, 62, 27 bp, while with F. gigantica 322, 269, 27 bp bands were obtained. Genotyping revealed no equivocal results. The conventional morphological parameters for species determination of Fasciola spp. endemic in Egypt were evaluated versus protein bands characterization and genotyping. It was concluded that conventional morphological and metric assessments were not useful for differentiation between F. gigantica and F. hepatica due to extensive overlap in the relative ranges. Similar conclusion was reached concerning protein band characterization where the patterns of protein banding were mostly similar. In contrast, genotyping using RFLP-PCR gave consistent results and clear differentiation between the two species. Considering the implications of proper speciation of endemic parasites on clinical evaluation, therapy, epidemiology, and control measures, speciation of parasites is currently revised on molecular basis. The presently used molecular tool is therefore recommended for further study to help draw a proper map for geographical distribution of Fasciola species.

Serological detection of Toxoplasma gondii in chronic renal failure patients and renal transplant recipients.

Toxoplasma gondii antibodies were detected in 78 patients with renal disease by ELISA. Patients were classified according to the renal status; chronic renal failure patients not on haemodialysis (G1 = 19), chronic renal failure patients on regular haemodialysis (G2 = 30), renal transplant recipient (G3 = 29) and 13 normal controls. Anti-Toxoplasma IgG & IgM antibodies were 36.8% & 10.5% in renal failure patients not on haemodialysis, 56.7% &16.7% in patients on regular haemodialysis and 69% & 24.1% in renal transplant recipients versus 23.1% & 0% in controls with statistical significant difference for Toxoplasma IgG antibodies only. Anti-Toxoplasma IgG antibodies levels of G3 were lower than that of G1. It was observed that the more the exposure to dialysis, the more the risk of toxoplasmosis. It was found that 85.71% of renal transplant recipient seropositive cases for anti-Toxoplasma IgM antibodies were detected in one year post-transplantation and 14.28% of cases after the first year of transplantation.

Risk factors predisposing to toxoplasmosis in chronic renal failure patients and renal transplant recipients.

This work evaluated risk factors predisposing to toxoplasmosis in chronic renal failure patients and renal transplant recipients. The present study included 91 cases classified according to their renal status into four groups; control group, renal failure patients not on haemodialysis, renal failure patients on regular haemodialysis and renal transplant recipients group. The age groups (< 20) and (30-) had the highest positivity for anti-Toxoplasma IgG & IgM antibodies in comparison to the other age groups. The results showed no sex difference in positivity rate for anti-Toxoplasma IgG & IgM in groups. There was no significant difference between groups regarding risk factors for contracting toxoplasmosis, clinical presentation suggestive of toxoplasmosis and diabetes mellitus. There was significant difference between all groups as regarding intake of immunosuppressive drugs and blood transfusion.