PROLONGED PROSTAGLANDIN INFUSION AND CORTICAL HYPEROSTOSIS IN AN INFANT WITH CYANOTIC CONGENITAL HEART DISEASE

Prostaglandins (PG) are commonly used in neonates with cyanotic congenital heart diseases to keep the ductus arteriosus patent. The definite treatment for these conditions is surgery. It is occasionally used for longer duration (weeks to months) in preterm babies. Reversible cortical hyperostosis is a relatively recently recognized side effect of prolonged prostaglandin therapy. We describe the case of an infant presenting this complication secondary to prolonged use of PGE1, with typical and extensive radiological findings. The enzymes (prostaglandin 15-OH dehydrogenase & prostaglandin -13 reductase) that catalyze the degradation of prostaglandins are widely distributed in many vascular beds including those of the spleen, kidney, adipose tissue, intestine, liver, testicles and lungs. PGE is normally rapidly inactivated by these tissues, particularly during passage through the lungs.18 However, infants with cyanotic congenital heart diseases that cause decreased pulmonary blood flow and reduced clearance of PGE may have a higher systemic concentration of PGE. In addition, these patients often receive pharmacologic doses of PGE to maintain the patency of the ductus arteriosus. The resultant higher PGE concentration in the blood may result in osseous changes. However the exact mechanism of cortical hyperostosis is not yet known. It may be a direct, dose-related stimulation of osteoblastic cells.