High prevalence of coeliac disease in siblings of children with type 1 diabetes.
Coeliac disease has been shown to occur more frequently among first-degree relatives of diabetic patients than in the general population. Our objective was to assess the prevalence of endomysium antibodies (EMA) in non-diabetic siblings of Czech diabetic children and to evaluate the effects of HLA-DQ polymorphisms in determining the genetic susceptibility to coeliac disease (CD) in these subjects. We investigated 240 siblings of diabetic children from 213 families (125 males and 115 females, aged 12.6+/-4.9 years, mean +/- SD). All subjects were tested for the total IgA level to exclude IgA deficiency, and for endomysium IgA to disclose CD. In five IgA-deficient subjects, anti-gliadin IgG was used instead. Small bowel biopsy was offered to subjects with confirmed positive EMA. The HLA-DQA1, -DQB1 genotypes were determined using PCR-SSP. Positive EMA were found in 9/240 (3.8%) subjects (three males, six females). The biopsy confirmed CD in six children, two had a normal mucosal finding and one refused the biopsy. The HLA-DQ2 polymorphism was more frequent among siblings with EMA (seven of nine) than in siblings without EMA (33%), corrected P = 0.031.


CONCLUSIONS
The 3.8% frequency of coeliac disease found in siblings of diabetic children is close to the 4.3% found previously in Czech children with type 1 diabetes mellitus and is substantially higher than the rate in the healthy children population.
Department of Paediatrics, 2nd Faculty of Medicine, V Uvalu 84, 150 06 Prague 5, Czech Republic. Zdenek.Sumnik@Lfmotol.cuni.cz
Zdenek
Z
Sumnik
Stanislava
S
Kolouskova
Hana
H
Malcova
Jan
J
Vavrinec
Jitrenka
J
Venhacova
Jan
J
Lebl
Ondrej
O
Cinek
D000293:Adolescent; D000328:Adult; D000888:Antibodies, Anti-Idiotypic / Q000097:blood; D001706:Biopsy; D002446:Celiac Disease / Q000150:complications* / Q000235:genetics / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D018153:Czech Republic; D003922:Diabetes Mellitus, Type 1 / Q000150:complications*; D005260:Female; D006683:HLA-DQ Antigens / Q000032:analysis; D059848:HLA-DQ alpha-Chains; D059866:HLA-DQ beta-Chains; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D008297:Male; D015995:Prevalence; D035781:Siblings
D000888:Antibodies, Anti-Idiotypic; D006683:HLA-DQ Antigens; D059848:HLA-DQ alpha-Chains; D059866:HLA-DQ beta-Chains; C069050:HLA-DQA1 antigen; C069051:HLA-DQB1 antigen; D007070:Immunoglobulin A