Hemophilia B in a neonate: unusual early spontaneous gastrointestinal bleeding.

A full-term male, healthy newborn infant suddenly developed melena and rectal fresh blood oozing at age of 4 days. He is the second patient described in the literature presenting a spontaneous gastrointestinal bleeding in the neonatal period as the first clinical manifestation of hemophilia B. The early appearance and severity of the hemorrhage, its short duration, and good response to Factor IX (inefficiency of vitamin K) was the characteristics of the affected neonate.