Severe, persistent neonatal hypoglycemia as a presenting feature in patients with congenital hypopituitarism: a review of our case series.

Background Persistent hypoglycemia (PH) beyond 3 days of life warrants investigation which includes a critical sample. We report our case series of five neonates who presented with PH as the first sign of congenital hypopituitarism. Design This is a case series. Methods/Results This is a case series of five neonates evaluated at our academic institution in a 3-year period (2013-2016), who presented with persistent severe hypoglycemia and were subsequently diagnosed with congenital hypopituitarism. All neonates were full term (mean gestational age 39.8 ± 1.4 weeks) born by caesarian section with a mean weight of 3.5 ± 0.16 kg and a mean length of 51.2 ± 1.2 cm at birth. All five neonates had PH beyond 3 days with an average blood glucose (BG) <35 mg/dL at presentation, requiring a mean glucose infusion rate (GIR) of 7.22 ± 1.98 mg/kg/min. The average BG during the critical sample was 42 ± 0.16 mg/dL (three patients). The mean duration of requirement of the glucose infusion was 6.2 ± 3 days during the immediate neonatal period. Diagnosis of the hypopituitarism took 2-52 days from the initial presentation of hypoglycemia. Besides growth hormone (GH) deficiency, cortisol deficiency was diagnosed in all the five neonates. Neuroimaging findings in all the neonates were consistent with pituitary stalk interruption syndrome (hypoplastic anterior pituitary, ectopic posterior pituitary [EPP] and interrupted pituitary stalk). Conclusions Hypoglycemia is a common metabolic complication affecting an infant in the immediate neonatal period. Delay in the diagnosis of hypopituitarism presenting as hypoglycemia is the result of the lack of awareness among neonatologists and/or pediatricians. We propose that providers be cognizant that PH can be the only presentation of hypopituitarism in the neonatal period. Therefore, having a high index of suspicion about this condition can avoid a delay in the evaluation, diagnosis and treatment of hypopituitarism.