Suspected betamethasone-induced leukemoid reaction in a premature infant

The use of antenatal corticosteroids in threatened pregnancies of less than 34 weeks' duration is a valuable tool for assisting fetal lung maturation. Although this practice has existed for over 20 years, little is known about a rare extreme elevation of the newborn's white blood cell count, called a leukemoid reaction. A case of leukemoid reaction is discussed to assist the clinician with the current thought processes and diagnostic differential behind this benign condition.