Plasma cortisol level and its relation to in-hospital mortality in acute kidney injury patients

Background Critically ill patients are at risk of developing critical illness-related corticosteroid insufficiency (CIRCI). This may present as hypotension, unresponsiveness to catecholamine infusions, and/or ventilator dependence. Acute kidney injury (AKI) usually complicates critically ill patients and is associated with hemodynamic instability. There is usually failure to predict the severity and to assess the response to therapy in AKI. The aim of this study was to assess the plasma cortisol level and its relation to hospital mortality in AKI patients. Patients and methods This is a prospective, observational study that included 66 patients with AKI admitted to the Dialysis and Nephrology Unit, Mansoura University Hospital, who were assessed clinically, followed by cortisol level assay done at the day of admission. Patients were followed clinically and biochemically till discharge. Patients were classified according to random plasma cortisol level into two groups: group 1 included 14 patients with random plasma cortisol of less than 10 μg/dl (CIRCI group) and group 2 included 52 patients with random plasma cortisol of greater than or equal to 10 μg/dl. Results There was a significant increase in platelet count in group 1 compared with group 2, while there was a significant decrease in serum potassium level in group 1 compared with group 2. Moreover, there was a significant decrease in urine output volume in group 1 compared with group 2 (P=0.03). Finally the hospital mortality rate was significantly higher in group 1 (CIRCI group) compared with group 2 (P=0.004). Conclusion AKI patients with low cortisol level at admission have higher mortality rate during the hospitalization period.