Absence or impaired response of fetal breathing to intravenous glucose is associated with pulmonary hypoplasia in congenital myotonic dystrophy.
Two fetuses of a patient affected with myotonic dystrophy were studied ultrasonically from 28 to 34 weeks' gestation. After a 1-hour observation period, an intravenous injection of 25 gm of 50% glucose solution was given to the mother. Fetal breathing movements were 0% during the control period and increased to only 10% at 90 minutes after the injection of glucose; the episode lasted approximately 30 minutes. The infants, who were delivered at 33 and 35 weeks, had generalized hypotonia, normal arterial cord blood gases, and died shortly after birth from pulmonary insufficiency, in spite of maximum ventilatory support. Postmortem pulmonary hypoplasia was confirmed by a lung weight/body weight ratio of less than 0.019. We postulate that fetal breathing activity and its response to the injection of glucose may be a potential clinical test by which normal fetuses can be differentiated from fetuses affected by neuromuscular disorders, including myotonic dystrophy.
D000328:Adult; D005260:Female; D005333:Fetus / Q000502:physiology*; D005947:Glucose / Q000008:administration & dosage*; D006801:Humans; D007231:Infant, Newborn; D007275:Injections, Intravenous; D008168:Lung / Q000002:abnormalities*; D009223:Myotonic Dystrophy / Q000150:complications / Q000151:congenital* / Q000175:diagnosis / Q000235:genetics; D009468:Neuromuscular Diseases / Q000151:congenital / Q000175:diagnosis; D011247:Pregnancy; D012119:Respiration
D005947:Glucose