RESUMEN
PURPOSE: Neutrophils are central to the defences against bacterial infection, and in neonates the number of neutrophils are decreased due to inhibited production and phagocytic function. This induces high mortality rates in infants suffering from neonatal sepsis. Exogenous GM-CSF can increase the number of neutrophils and improve the phagocytic function. To establish the most cost effective dose of exogenous granulocyte-macrophage colony-stimulating factor in infected neonates, we divided infected patients into two groups. The serum level of granulocyte-macrophage colony stimulating factor, white blood cell count and absolute granulocyte count were compared. METHODS: This study included 22 infants with infection, admitted to the neonatal intensive care unit of Chungnam National University Hospital, between February 1998 and September 1999. Infected infants were divided into two treatment groups with exogenous GM-CSF 3 microgram/kg/day & 10 microgram/kg/day. The total WBC count, the absolute granulocyte count and the serum GM-CSF concentration of peripheral blood before use of GM-CSF, and those of 2nd, 5th and 7th day after use were compared. RESULTS: In 3 microgram/kg/day group, WBC count and the absolute granulocyte count and the serum GM-CSF concentration reached a peak after the 2nd injection of GM-CSF. In 10 microgram/kg/day group, the WBC count and the absolute granulocyte count increased gradually until 7th day. There was tendency for the total WBC counts, the absolute granulocyte count and the serum GM-CSF concentration of peripheral blood in 10 microgram/kg group to increase more than those of 3 microgram/kg group, after exogenous GM-CSF treatment. CONCLUSION: In neonates, we propose the exogenous GM-CSF treatment 10 microgram/kg/day as being more effective than 3 microgram/kg/day protocol, which is one of the safest and most effective methods to increase the total WBC count, the absolute granulocyte count and the serum GM-CSF concentration of peripheral blood.