Introduction: Brain edema is a rare, but feared complication of diabetic ketoacidosis (DKA) with highmortality and morbidity. Pathogenesis of the origin of brain edema is still uncertain and risk factors, which ensue in this severe complication, are not precisely defined. Methods: In the retrospective study the authors followed the frequency of occurrence of DKA and brain edema in children with diabetesmellitus of 1st type(DM1) in the period of January 1999 to June 2002. Risk factors involved in the development of brain edema were evaluated. Results: The criteria for DKA were fulfilled in 27 out of 101 children admitted for DM1, the diagnosis was established in 24 new patients. Clinical findings in four newly diagnosed patients corresponded to the established diagnosis of brain edema. All four patients with brain edema were transferred to their district children’s ward after 4 to 27 hours after admission. The values of pH and pCO2 in blood were lower in patients with brain edema than the mean values in other 23 children with DKA. The duration of Kussmaul’s breathing was markedly longer in patients with brain edema and corresponded to the duration of severe metabolic acidosis. Their mean age did not differ from other children with DKA. Blood levels of urea were comparable in both groups.None of the patients died during hospitalization. Conclusion: The duration of severe metabolic acidosis, hypocapnia and DKA as the first manifestation of DM1 were evaluated as risk factors for the development of brain edema in the course of DKA at the child age in accordance with present data in literature.

        Key words: diabetes mellitus, diabetic ketoacidosis, brain edema, hypocapnia