title: GAD65 antibody prevalence and association with thyroid antibodies, HLA-DR in Chinese children with type 1 diabetes mellitus.
abstract: Persistent humoral autoimmunity to the enzyme glutamic acid decarboxylase (GAD) has been described in a substantial proportion of patients with type 1 diabetes mellitus. Higher prevalence of GAD antibody in diabetes patients using a new radioligand-binding assay with recombinant human GAD65 antibodies (GAD65Ab) has been seen in several studies. Using this method, we have reassessed the prevalence of GAD65Ab and investigated the association of GAD65Ab with HbA1C values, C-peptide values, HLA-DR typing and thyroid autoimmune antibody in 70 Chinese children with type 1 diabetes mellitus (mean age of onset 8.21+/-3.84 years, mean duration 3.39+/-2.54 years). Our result revealed that GAD65 antibodies were present in 54.3% (38/70) of diabetes children. There was no significant difference in gender, diabetes onset and duration, HbA1c, C-peptide concentration and frequencies of HLA DR3, DR4, DR9, DR3/DR4, DR3/DR9 and DR4/DR9 genotypes between GAD65Ab+ and GAD65Ab- groups. There was no negative correlation between GAD65Ab values and duration of diabetes in those with GAD65Ab positivity (r=-0.239, P>0.05). The frequencies of antimicrosomal and anti-thyroglobulin antibodies in GAD65Ab+ (13.5,8.1%, respectively) were not different from GAD65- patients (9.4,12.5%, respectively).
authors.affiliation: Department of Laboratory Medicine, Kaohsiung Medical University Hospital, No 100, Shih Chuan 1st Road, Kaohsiung, Taiwan, ROC. chen_bh@hotmail.com
authors.forename: B H
authors.initials: BH
authors.lastname: Chen
authors.forename: S B
authors.initials: SB
authors.lastname: Chung
authors.forename: W
authors.initials: W
authors.lastname: Chiang
authors.forename: M C
authors.initials: MC
authors.lastname: Chao
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D044466:Asian People; D001323:Autoantibodies / Q000097:blood*; D002096:C-Peptide / Q000097:blood; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000276:immunology*; D005260:Female; D005968:Glutamate Decarboxylase / Q000276:immunology*; D006442:Glycated Hemoglobin / Q000032:analysis; D006684:HLA-DR Antigens / Q000097:blood*; D006801:Humans; D018828:Immunoglobulins, Thyroid-Stimulating / Q000097:blood*; D007223:Infant; D007527:Isoenzymes / Q000276:immunology*; D008297:Male; D011869:Radioligand Assay; D011994:Recombinant Proteins; D013624:Taiwan
chemical_list: D001323:Autoantibodies; D002096:C-Peptide; D005968:Glutamate Decarboxylase; D006442:Glycated Hemoglobin; D006684:HLA-DR Antigens; D018828:Immunoglobulins, Thyroid-Stimulating; D007527:Isoenzymes; D011994:Recombinant Proteins; C401141:glutamate decarboxylase 2