Nested PCR targeting intergenic spacer (IGS) in genotyping of Giardia duodenalis isolated from symptomatic and asymptomatic infected Egyptian school children.

Distinct sequences of Giardia duodenalis assemblages raised the hypothesis that certain assemblages may contribute to its clinical outcome. However, sequences analysis is time consuming, expensive, and needs many manual operations. Nested PCR targeting intergenic spacer (IGS) region was applied successfully to genotype G. duodenalis. This study aimed to identify the prevalence of G. duodenalis assemblages among giardiasis school children and its relation to the presence of symptoms using nested IGS/PCR. Of 65 microscopically confirmed Giardia-positive samples, 65 samples were genotyped proving high sensitivity (92.3%) of IGS/PCR. Negative IGS/PCR samples were also negative for ß-giardin gene. Subassemblage AI was the commonest with 66.6% (20/30) among asymptomatic children compared to 53.3% (16/30) of symptomatic, while assemblage B was found in 40% (12/30) of symptomatic compared to 20% (6/30) of asymptomatic. The difference was significant. AII was only found in asymptomatic with 13.4% (4/30), while mixed infections (AI&B) were recorded only in 6.6% (2/30) of symptomatic group. A significant relation was found between younger children susceptibility for AI and B infections as presented in 77.7 (12/16) and 83.3% (10/12) of symptomatic, respectively, and 80 (16/80) and 33.4% (2/4) of asymptomatic, respectively. Significant relations were found between AI with intermittent diarrhea and B with chronic. A significant relation was found between assemblage distributions and heavy infection intensity. In conclusion, higher incidence of assemblage B among symptomatic children compared to asymptomatic could denote its possible pathogenic potential.

INF-gamma, IL-5 and IgE profiles in chronic schistosomiasis mansoni Egyptian patients with or without hepatitis C infection.

The immune response against clinical forms of chronic schistosomiasis mansoni patients with or without HCV infection was evaluated by assays the serum levels of IFN-gamma and IL-5 for estimate the cell mediated immunity and IgE level to estimate the humoral immunity. This study included three patient groups. G.I included 25 patients with intestinal schistosomiasis, G.II included 15 patients with hepatosplenic schistosomiasis and G.III included 40 patients hepatosplenic schistosomiasis co-infected with HCV. Control G.IV included 15 healthy persons with matched age and sex. The intestinal group had high IFN-gamma (92%), normal level of IL-5 and IgE. The immune response was mainly 100% Th-1 response. The hepatosplenic patients had high IFN-gamma (26.7%), IL-5 (86.7%) and IgE (73.3%). The immune response was 73.4% Th-0, 13.3% Th-1 and 13.3% Th-2. The co-infected group had high IFN-gamma (62.7%), IL-5 (100%) and IgE (92.5%). The immune response was 62.5% Th-0 and 37.5% Th-2 immunity. The shift to Th-0 and Th-2 immunity as well as associated depression of Th-1 in mixed group of patients may be playing a role in the persistence and severity of both diseases. Such immunity defects add to decrease challenge against HCV clearance.