Quantification of islet-cell antibodies and prediction of insulin-dependent diabetes.
The sensitivity and predictive value of islet-cell antibodies (ICA) for the future onset of insulin-dependent diabetes mellitus (IDDM) were determined in 719 first-degree relatives of IDDM patients. ICA were quantified in Juvenile Diabetes Foundation (JDF) units, by indirect immunofluorescence in serum samples taken during prospective follow-up of up to 10.5 years. The threshold of ICA detection was 4 JDF units. ICA were detected in the first sample of 26 (3.3%) of the relatives, compared with 12 (2.2%) of 540 controls (298 blood donors and 242 healthy children). ICA were detected in follow-up samples from a further 14 relatives. IDDM developed in 14 (35%) of the 40 relatives with detectable ICA at any time and in 2 (0.3%) relatives without detectable ICA. In all 5 relatives with peak ICA levels above 80 JDF units IDDM developed within follow-up of 7 years; survival without IDDM at 10 years was 27% among relatives with peak ICA levels of 20-80 JDF units and 82% for peak ICA levels of 4-20. The predictive value for IDDM development within 10 years ranged from 40% (threshold 4 JDF units) to 100% (80 JDF units) and the sensitivity from 31% (80 JDF units) to 88% (4 JDF units).
Bonifacio
E
E
Department of Immunology, University College, Middlesex School of Medicine, London, UK.
Bingley
P J
PJ
Shattock
M
M
Dean
B M
BM
Dunger
D
D
Gale
E A
EA
Bottazzo
G F
GF
D000206:Actuarial Analysis; D000293:Adolescent; D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000032:analysis*; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000209:etiology / Q000235:genetics / Q000276:immunology* / Q000517:prevention & control; D005260:Female; D005455:Fluorescent Antibody Technique; D005500:Follow-Up Studies; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis*; D007515:Islets of Langerhans / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies
D001323:Autoantibodies; D007074:Immunoglobulin G; C024211:islet cell antibody