Sleep apnea and respiratory dysfunction in congenital myotonic dystrophy.

A case of neonatal Myotonic Dystrophy (MD) is presented. A 35 week old 3570 g baby was born to a mother affected by MD and pregnancy-induced unstable diabetes. Soon after birth, he developed apnea, severe hypoglycemia, hypocalcemia, hypotonia and mild respiratory distress. His clinical course improved during the following days, but persistent episodes of desaturation and/or cyanosis did not subside; hypotonia was mild. A polysomnographic recording showed mixed central and obstructive apnea. DNA testing showed trinucleotide repeat expansion mutations diagnostic of MD. The baby was discharged with home-sleep monitoring and breast-feeding. Recurrent apnea/bradycardia was the main clinical feature in this case of congenital MD, with increased risk of an acute life-threatening event.