Absolute and relative adrenal insufficiency in children with septic shock*

Abstract

Corticosteroid replacement improves outcome in adults with relative adrenal insufficiency and catecholamine-resistant septic shock. We evaluated the relationship of absolute and relative adrenal insufficiency to catecholamine-resistant septic shock in children. Prospective cohort study. University hospital pediatric intensive care unit in Brazil. Fifty-seven children with septic shock. Children with HIV infection, those with a history of adrenal insufficiency, and those submitted to any steroid therapy or etomidate within the week before diagnosis of septic shock were excluded. None. A short corticotropin test (250 microg) was performed, and cortisol levels were measured at baseline and 30 and 60 mins posttest. Adrenal insufficiency was defined by a response < or =9 microg/dL. Absolute adrenal insufficiency was further defined by a baseline cortisol <20 microg/dL and relative adrenal insufficiency by a baseline cortisol >20 microg/dL. Absolute adrenal insufficiency was observed in 18% of children, all of whom had catecholamine-resistant shock. Relative adrenal insufficiency was observed in 26% of children, of whom 80% had catecholamine-resistant and 20% had dopamine/dobutamine-responsive shock. All children with fluid-responsive shock had a cortisol response >9 microg/dL. Children with adrenal insufficiency had an increased risk of catecholamine-resistant shock (relative risk, 1.88; 95% confidence interval, 1.26-2.79). However, mortality was independently predicted by chronic illness or multiple organ failure (p < .05), not adrenal insufficiency. Absolute and relative adrenal insufficiency is common in children with catecholamine-resistant shock and absent in children with fluid-responsive shock. Studies are warranted to determine whether corticosteroid therapy has a survival benefit in children with relative adrenal insufficiency and catecholamine-resistant septic shock.