TRANSIENT NEONATAL DIABETES MELLITUS (TNDM) AND SUBSEQUENT (10 yr later) PERRANENT IDDM UNRELATED TO AUTOIMMUNITY

Abstract

We describe the sixth case reported until now of permanent diabetes not associated with serological evidence of autoimmunity in a child who developed INDM 10 yr earlier. A small for gestational age infant developed hyperglycemia at 25 days of age and required insulin therapy for the first 9 mo of life. During a 10 yr longitudinal follow-up, ICA, IAA and organ specific and non-specific autoantibodies were negative, but sequential IVGII showed a first phase insulin reponse (FPIR) < 1st centile (15-28) uU/ml) and mean HbA1c value was 6.1 ± 0.8%. Transient hyperglycemia and glucosuria were recorde at age 4 and 6.3 yr during and intercurrent illness. HLA type was DR2. At age 10 yr & 1 mo (Tanner stage 1-2)a progressive blood glucose increase was observed from 4 to 7 a.m. with a spontaneous normalisation before noon. FPIR was 12 uU/ml). Six isophane insulin units injected at 10 p.m. prevented glycemia increase. Six mo latter (FPIR = 18 uU/ml; ICA & IAA negative) & permanent insulin treatment was started. During 3 yr period preceding insulin therapy, a progressive decrease in growth velocity was observed with high stimulated GH and low IGF1 levels. With insulin therapy (0.51 ± 0.15 U/kg/day) a catch-up growth and a normalization of IGF1 were obtained. The physiological increase in insulin resistance during puberty could be at the origin of (definitive?) insulin dependence in this subject.