Transient or persistent neonatal hypoglycemia

Specialty: Pediatrics.

• Low blood glucose in the newborn
• symptomatic neonatal hypoglycemia

Why it occurs

• Transient hyperinsulinism in the infant of a diabetic mother (chronic maternal hyperglycemia induces hyperplasia of fetal pancreatic beta cells, which continue to produce excess insulin after birth)
• Decreased glycogen reserves due to intrauterine growth retardation (IUGR) or extreme prematurity (loss of glycogen and fat accumulation in the third trimester)
• Neonatal sepsis or hypoxic-ischemic encephalopathy (excessive glucose consumption due to systemic or cerebral metabolic stress)
• Congenital hyperinsulinism (most common persistent cause of severe refractory hypoglycemia due to mutations in the KATP potassium channels of the pancreatic beta cell, ABCC8 and KCNJ11 genes)
• Panhypopituitarism or isolated deficiency of growth hormone or cortisol (absence of counterregulatory glucose hormones).

Initial workup

Immediate determination of capillary glycemia always confirmed by analysis of glycemia in venous plasma. At the time of documenting severe hypoglycemia (less than 40 mg/dl), the critical blood sample ("critical hypoglycemia sample") should be drawn to measure: insulin, C-peptide, growth hormone, cortisol, lactate, free ketone bodies (acetoacetate and beta-hydroxybutyrate), acylcarnitine profile, and free fatty acids. Systematic urine in the first post-crisis urination to investigate ketonuria and reducing substances.

Standard management

• 10% Glucosated Whey — immediate treatment of choice; In asymptomatic patients at risk, oral or tube feeding is prioritized; If there are symptoms or blood glucose < 25 mg/dl, infuse a bolus of 2 ml/kg of 10% glucose solution intravenously over 5-10 minutes, followed by a continuous infusion of glucose at a glucose infusion rate [VIG] of 4 to 8 mg/kg/minute, increasing progressively as needed.
• Glucagon — counterregulatory hormone to mobilize emergency glycogen stores if an intravenous route is not available; dose of 0.1 to 0.2 mg/kg IM or SC
• Diazoxide (pancreatic potassium channel agonist drug, indicated in confirmed congenital hyperinsulinism; dose of 5 to 15 mg/kg/day orally divided into 3 doses; monitor fluid retention).