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To compare the phenotypic and gene frequencies of the HLA system in celiac and healthy subjects the same geographical area.HLA A, B, C, DR and DQ phenotypic and gene frequencies have been estimated in 38 celiac children and healthy subjects. The HLA typing has been done according to the microlymphocytotoxicity assay. The individual HLA antigen frequencies in each group have been compared by Chi-square test using Yates correction. For each specificity, the strength of association with celiac disease has been estimated by Odds Ratio and 95% confidence limit.The comparative study of both population show increased phenotypic and gene frequencies among celiac patients and significant differences compared with healthy subjects for B8, Cw7, DR3, DR7 and DQ2. On the contrary, Cw4 and DQ1 phenotypic and gene frequencies are significantly increased in the control population.Our findings support the role of HLA antigens as predisposing factors for celiac disease. The presence of Cw4 and DQ1 can be a protective factor against such disease.

Celiac disease is closely correlated with certain human lymphocyte antigen (HLA) alleles. The aim of this study was to compare linkage disequilibrium parameters and the frequencies of the two loci haplotypes: HLA A/B, A/C, A/DR, A/DQ; HLA B/C, B/DR, B/DQ; HLA C/DR, C/DQ and HLA DR/DQ in children with celiac disease and in a control population within the same geographical area.Thirty-eight children with celiac disease, aged 5months to 18years at diagnosis, were HLA typed by microlymphocytotoxicity assay using T and Bcells separated by monoclonal antibody labeled immunomagnetic particles. The frequency of each haplotype of two loci (Hij) depends on the frequency of each allele (pi and pj) and on a correction factor delta, according to the formula: Hij5 Dij1(pi3pj). The existence of a correction factor delta, or linkage disequilibrium, was assessed by a chi square test using 2 X 2contingency tables for gametic association.Among children with celiac disease the most frequent and significant haplotypes were A1/B8, A9/B5, A19/B12, A28/B22, A28/Cw1, A9/DQ3, B8/Cw7, B18/Cw5, B22/Cw1, B5/DR5, B8/DR3, B12/DR7, B5/DQ3, DR3/DQ2, DR4/DQ8 (3) and DR5/DQ3, showing a positive linkage disequilibrium. Negative linkage disequilibrium was found between B18/Cw7, B12/DR3, Cw4/DR3 and DR3/DQ3.Our findings show that the frequency of A1/B8,A19/B12, B8/DR3,B12/DR7 and DR3/DQ2 haplotypes is higher in children with celiac disease than in the control population and suggest that these two loci haplotypes confer susceptibility to celiac disease.

The persistence of serological positivity was studied in 21 children with surgically proven hydatidosis. The children had been previously operated on between 10 months and 7 4/12 years before serum samples were extracted. Forty-eight people (19 adult and 39 children) were included as a control group. E.L.I.S.A. specific IgE and indirect hemagglutination techniques were used for the diagnosis of hydatid disease. Studies of the immunoglobulins and complement components IgG, IgA, IgM, IgE, C3, C4, C5 and factor B were done on the sera from the 21 children with histories of equinococciasis. The results are expressed according to the location and physical condition of the cyst, the time passed after surgery, the number of cysts and the number of surgical operations. We found persistence of positivity of up to 5 4/12 years for indirect hemagglutination and up to 6 7/12 years for specific IgE, in cases without evidence of clinical parasitation so we think that the postoperative control must be based on several serological determinations. The concordance between the two specific serological tests (specific IgE and indirect hemagglutination) was 80.95%; specific IgE having appeared more sensitive especially in cases of hepatic location. The results concerning the total IgE determination were highlighted in the immunoglobulin studies. We consider total IgE as being only orientative, because of the frequency with which it is found elevated in childhood diseases.