alpha 1-antitrypsin deficiency with fatal intracranial hemorrhage in a newborn

A 4-week-old boy had a fatal intracranial hemorrhage resulting from vitamin K deficiency. The infant had received no vitamin K prophylaxis and was exc lusively breastfed. At autopsy, examination of the liver showed cholestasis and fibrosis. DNA was isolated from a blood spot on a Gutherie sample card obtained from the infant for routine metabolic screening. This DNA was use d for alpha 1-antitrypsin genotyping studies. Genotyping studies identified homozygosity for the point mutation 9989G-->A, confirming a diagnosis of a lpha 1-antitrypsin deficiency (ZZ phenotype), and resulted in appropriate s creening of siblings born after this child's death. alpha 1-antitrypsin def iciency should be considered in the differential diagnosis of infants with late hemorrhagic disease of the newborn. Use of blood from the metabolic sc reening card as a source of DNA allowed confirmation of this diagnosis afte r the infant's death.