Anti-CD38 autoimmunity in children with newly diagnosed type 1 diabetes mellitus.

Endocrinology Unit, Azienda Ospedaliera Careggi and University of Florence, Italy.
Journal of pediatric endocrinology & metabolism: JPEM (Impact Factor: 0.71). 12/2005; 18(12):1417-23. DOI: 10.1515/JPEM.2005.18.12.1417
Source: PubMed

ABSTRACT To test for anti-CD38 autoimmunity in children with newly-diagnosed type 1 diabetes mellitus (DM1).
Serum anti-CD38 autoantibodies were detected by Western blot in 270 children (130 girls, 140 boys, mean age 8 +/- 4 years) with newly-diagnosed DM1 and 179 gender- and age-matched non-diabetic children. In 126 diabetic children, another blood sample was obtained 15 +/- 4 months after the diagnosis.
Anti-CD38 autoantibody titers at least 3 SD above the mean value for the control group were found in 4.4% of children with DM1 vs 0.6% of controls (chi2 = 5.8, p <0.016). No statistical differences were observed between anti-CD38 positive and negative patients in terms of phenotype. At follow-up, of six diabetic children who were positive for anti-CD38 antibodies, two were new cases. A positive correlation was found between the antibody titer of diabetic sera at diagnosis and follow up (r = 0.46, p <0.0001).
An autoimmune reaction against CD38, a protein expressed in human islets, is associated with newly-diagnosed DM1. In children with DM1, CD38 autoimmunity increases with time and persists.

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