Introduction: Hyperglycemia is a common event in neonates, frequently associated with specific clinical conditions (sepsis, drugs or intravenous fluids) other than neonatal diabetes. Unusual endocrino-metabolic syndromes must be considered whenever initial studies are inconclusive.
Case report: Newborn term female was admitted at the NICU for intrauterine growth restriction with fluxometric changes and low birth weight (1710 g). Gestational history included oligoamnios and maternal hypertension and autoimmune thyroiditis. At day 11 tachycardia and hyperglycemia occurred, resolving with enteric pause and intravenous fluids with glucose 5 mg/kg per min; complete blood count and acid base status were normal and cultures were sterile. After returning to enteric feeding hyperglycemia recurred, and insulin therapy was maintained for 24 hours with normoglycemia; ketonemia and ketonuria were negative and glycated hemoglobin was 4.7%. At day 28 tachycardia and hyperglycemia recurred, resolving with enteric pause and intravenous fluids; blood chemistry showed severe hypertriglyceridemia (1589 mg/dl) and she initiated a very low lipid formula and supplementation with soy and corn oils. Genetic testing for congenital diabetes was negative; abdominal ultrasound and echocardiogram were normal. She was discharged at day 34, with a net weight increase of 20 g/day. In the next months, diet was managed targeting triglyceride levels, with continuous adjustments in the oils, low lipid formulas, LC-PUFAS and carbohydrates supplements. Glucose levels were normal, and apolipoproteins A, B and lipoprotein(a) were normal. Hyperinsulinemia (>100 uU/ml) was noted. At physical examination she progressively developed a lipodystrophic phenotype, with absent subcutaneous fat, muscle hypertrophy, hepatomegaly and phlebomegaly. At 8 months-old a breast button was noted, with no progression of sexual characters, normal growth velocity, and concordant skeletal and chronological age. At this time, Bernardinelli-Seip congenital lipodystrophy (BSCL) criteria were met, and genetic testing confirmed a compound heterozygous in BSCL2 gene: c.604C>T (p.Arg202*) and c.399C>A (p.Tyr133*). Echocardiogram revealed non-obstructive hypertrophic cardiomegaly, and abdominal ultrasound confirmed severe hepatomegaly with hepatic steatosis. Hypoleptinemia was found, and she is waiting authorization to start metreleptin therapy.
Discussion: The authors present a case of BSCL as the primary cause of neonatal insulin resistance and hyperglycemia. BSCL is characterized by the absence of functional adipocytes with storage of lipids in muscle and liver. Besides early insulin resistance, other endocrine manifestations that should be regularly surveilled include diabetes mellitus of difficult control, hirsutism, and precocious puberty.
27 - 29 Sep 2018
European Society for Paediatric Endocrinology