title: Prevalence of beta-cell and thyroid autoantibody positivity in schoolchildren during three-year follow-up.
abstract: The prevalence of autoantibodies against the 65 kD isoform of glutamic acid decarboxylase (GAD65Ab), insulin (IAA), islet cells (ICA), thyroid peroxidase (TPOAb) and thyroglobulin (TgAb), in relation to HLA-DR types, was assessed in 310 (HLA in 280) twelve-year-old children during three-year follow-up. Altogether, 26.8% (83/310) of the children were found to carry at least one autoantibody. The HLA-DR3/DR4 genotype was significantly more prevalent in the subgroup of children GAD65Ab-positive on at least one occasion than among GAD65Ab-negative children [33% (2/6) vs. 5% (12/274); p = 0.031, as was the HLA-DR4/x genotype among children seropositive for at least one thyroid autoantibody, compared to the corresponding seronegative subgroup 152% (34/65) vs. 34% (74/215); p=0.01]. The proportion of children seropositive in at least one of the three tests was 1.9% (6/310) for GAD65Ab, 2.6% (8/310) for IAA, 5.2% (16/310) for ICA, 11.3% (35/310) for TPOAb and 19.4% (60/310) for TgAb. All autoantibodies except GAD65Ab tended to disappear during follow-up, and at the three-year follow-up IAA had disappeared in 50% (2/4) of cases, ICA in 67% (6/9), TPOAb in 30% (6/20) and TgAb in 38% (18/47) of cases. The turnover of seropositive subjects and the large proportion of children seropositive for at least one islet or thyroid autoantibody during a three-year follow-up suggest transient autoantibodies to be more common than is discernible in cross-sectional investigations.
authors.affiliation: Department of Pediatrics, University Hospital of Malmö, University of Lund, Sweden. bengt.lindberg@pediatrik.mas.lu.se
authors.forename: B
authors.initials: B
authors.lastname: Lindberg
authors.forename: A
authors.initials: A
authors.lastname: Carlsson
authors.forename: U B
authors.initials: UB
authors.lastname: Ericsson
authors.forename: I
authors.initials: I
authors.lastname: Kockum
authors.forename: A
authors.initials: A
authors.lastname: Lernmark
authors.forename: M
authors.initials: M
authors.lastname: Landin-Olsson
authors.forename: G
authors.initials: G
authors.lastname: Sundkvist
authors.forename: S A
authors.initials: SA
authors.lastname: Ivarsson
mesh_terms: D000293:Adolescent; D001323:Autoantibodies / Q000097:blood*; D002648:Child; D005500:Follow-Up Studies; D005968:Glutamate Decarboxylase / Q000276:immunology*; D015803:HLA-DR3 Antigen / Q000276:immunology; D015804:HLA-DR4 Antigen / Q000276:immunology; D006801:Humans; D007328:Insulin / Q000276:immunology*; D007453:Iodide Peroxidase / Q000276:immunology*; D007515:Islets of Langerhans / Q000276:immunology*; D007527:Isoenzymes / Q000276:immunology*; D013961:Thyroid Gland / Q000276:immunology*; D013997:Time Factors
chemical_list: D001323:Autoantibodies; D015803:HLA-DR3 Antigen; D015804:HLA-DR4 Antigen; D007328:Insulin; D007527:Isoenzymes; C024211:islet cell antibody; D007453:Iodide Peroxidase; D005968:Glutamate Decarboxylase; C401141:glutamate decarboxylase 2