Effect of granulocyte colony-stimulating factor on granulopoiesis of congenital neutropenic children.

We report on two patients with congenital neutropenia, who were treated with filgrastim (recombinant human granulocyte-colony stimulating factor, G-CSF). A poor growth of bone marrow colonies and low sensitivity of colony forming units to colony stimulating factor in vitro before treatment seemed to be associated with a requirement for higher doses of G-CSF to achieve good clinical response in vivo.