Severe Hyperinsulinaemic Hypoglycaemia in a Baby Born to a Mother Taking Oral Ritodrine Therapy for Preterm Labour

Abstract

Hyperinsulinism of infancy is a major cause of persistent hypoglycaemia in the newborn period. Transient mild self-limiting hyperinsulinaemia and hypoglycaemia have been described in neonates born to mothers taking ritodrine therapy for premature labour. Ritodrine crosses the placental barrier and enters the fetal circulation readily but the mechanism of how it causes hyperinsulinaemia and hypoglycaemia is unclear. We report the case of severe prolonged hyperinsulinaemic hypoglycamia in a neonate born to a mother taking ritodrine therapy from 16 weeks’ gestation for preterm labour. The hyperinsulinaemic hypoglycaemia was managed with oral nifedipine as diazoxide was contraindicated due to fluid overload. Possible mechanisms of ritodrine-induced hypoglycaemia and insulin secretion are discussed.

Management Strategies for Neonatal Hypoglycemia

“…The times of additional interventions in these case reports vary greatly from within the first 36 hours of life 23 to 7 to 10 days of life. 24 It may be prudent to delay additional therapies as long as possible (up to 14 days of life) to allow the transient forms of hypoglycemia to resolve in order not to expose infants to unnecessary drug therapy. Other than the infant who continues to experience consistent episodes of hypoglycemia or requires persistently high dextrose concentrations (>D25%), most infants should remain on dextrose infusions for at least 7 to 10 days before the addition of other therapeutic options is considered.…”

“…This treatment approach has been discussed more recently in the literature in patients fro whom other therapeutic options have failed; however, only 4 patients have been described in the published case series. 24,48,49 Nifedipine was initiated at 0.25 to 0.3 mg/kg/day, orally, divided every 8 hours. Doses were increased by 0.1 mg/kg/day until patients were euglycemic and dextrose was weaned.…”

Prolonged neonatal-onset hyperinsulinism in the absence of predisposing factors

“…None of the infants were prenatally exposed to maternal drugs associated with neonatal hyperinsulinism, such as ritodrine or thiazide diuretics [16]. Perinatal complications that commonly predispose to prolonged neonatal hyperinsulinism, such as IUGR or severe asphyxia [6,7,17] were absent in all infants.…”

Drug-Induced Hypoglycemia in Neonates Born to Nondiabetic Women Treated with Medications during the Pregnancy or the Labor: A Systematic Review of the Literature

“…71 In one case, hypoglycemia was severe and recurrent. 72 Dose-response gradient: no dose effect has been evaluated.…”

“…74 Management: the management of severe transient hyperinsulinemic hypoglycemia in a neonate born to a mother taking ritodrine from 16 weeks of gestation for preterm labor required treatment with continuous IV glucose infusion (up to 12 mg/kg/min) and oral nifedipine. 72 Quality of the studies: the available data derive mainly from retrospective studies or case series with small sample sizes.…”