Pathogenesis of diabetic ketoacidosis: a reappraisal.

Abstract

This study reviews the pathogenic hormonal abnormalities (insulin deficiency and stress hormone excess) in diabetic ketoacidosis. The data both supporting and negating a primary role for insulin deficiency in the pathogenesis of diabetic ketoacidosis are examined. Evidence implicating excess stress hormone secretion as a necessary event in the development of severe metabolic decompensation is discussed. The data suggest that diabetic ketoacidosis may be prevented by correcting either the relative deficiency of insulin or the excess secreation of one or a combination of the stress hormones. Studies supporting a primary role for insulin deficiency in the pathogenesis of diabetic ketoacidosis include the beneficial therapeutic response to insulin administration in ketoacidosis, development of ketoacidosis; and (3) stress hormone excess is necessary for fulminant ketoacidosis to be manifested.s following insulin withdrawal from diabetic man and animals, and hypoglycemic and hypoketonemic effects of insulin. Studies negating a primary role for insulin deficiency in ketoacidosis include the "normal" plasma insulin concentration in the majority of ketoacidotic cases, delayed onset of ketoacidosis after insulin withdrawal from diabetic man, and lack of hypolipolytic and hypoketonemic effect of insulin without prior stress hormone adipocyte and hepatocyte stimulation. Evidence that stress hormones (glucagon, catecholamines, cortisol, and growth hormone) contribute to the metabolic decompensation of ketoacidosis includes: (1) in all cases of ketoacidosis, at least one stress hormone is always elevated; (2) pharmacologic blockade of each of the stress hormones reduces the rate and/or frequency of metabolic decompensation in diabetic man; (3) removal of the pituitary and/or the adrenal gland in diabetic animals completely prevents the development of ketoacidosis after insulin withdrawal; and (4) administration of each of the four stress hormones under appropriate conditions induces metabolic decompensation in diabetic man with "normal" circulating levels of plasma insulin concentration. From these studies, the following conclusions are supported: (1) absolute insulin deficiency is an unusual cause of ketoacidosis; (2) the presence of relative insulin deficiency is necessary for the development of ketoacidosis; and (3) stress hormone excess is necessary for fulminant ketoacidosis to be manifested.