IMPE Abstracts

Neonatal Diabetes (ND) is a rare genetic disease (1 in 90,000 live births); most cases will be diagnosed before 6 months of age. The third cause by frequency, is mutations of the insulin gene (INS); the majority are heterozygous mutations affecting the structure of preproinsulin; these are transmitted in an autosomal dominant manner.

Clinical case: Third Child of non-consanguineous parents, male, controlled pregnancy at high obstetric risk by type 1 diabetic mother with insulin therapy, hypertension and doppler ultrasound with single umbilical, glycated hemoglobin (HbA1c) of pregnancy 6.3%, complete corticosteroid therapy, 34 weeks premature caesarean section premature rupture of the membrane, birth weight: 2kg. (SD -1.9) birth size: 39cm. (SD -3.3). Newborn physical exam unique umbilical artery, normal abdominal ultrasound, connatal infection received antibiotic treatment, glycemic alteration 7 days of life but no value above 190, it is performed echocardiography shows congenital heart disease, refer to our hospital for surgical. He was readmitted at one month of life, laryngeal stridor associated with severe respiratory distress with the need for nebulized adrenaline plus dexamethasone and subsequent connection to invasive mechanical ventilation with hyperglycemia up to 541 without acidosis or ketosis with Hba1c of 5.4%, GAD antibodies (-), rest negative, C peptide is not taken, start pump continuous insulin infusion up to 0.04 IU / kg / hour progressive decrease until suspension with normoglycemia. He was he was discharged home. After 6 months, he was readmitted to the intensive care unit due to pneumonia with glycemia up to 427mg/dl with ketones without acidosis, Hba1c of 11.8%, continuous insulin infusion pump started up to 0.08 iu / kg / hour, insulin was started subcutaneous, immunological markers of diabetes are taken again, resulting in all negative antibodies and c-peptide of 1.8ng / ml, a change from insulin to glibenclamide is made with initial a favorable response. 22q11.2 deletion syndrome study was negative. Normal Karyotype 46,XY. A genetic study was carried out on him and his parents where he and his mother resulted heterozygous for a pathogenic variant in the INS gene c.325T>G (p.Cys109Gly). With this result, glibenclamide was discontinued and intensified therapy with subcutaneous insulin was started.

Discussion: Heterozygous INS gene mutations can cause isolated permanent early-infancy diabetes. The identification of insulin mutations as a cause of neonatal diabetes will facilitate the diagnosis and possibly, in time, treatment of this disorder.