Objectives: To evaluate cortisol levels and prevalence of adrenal insufficiency in patients with severe community-acquired pneumonia (CAP).
Design and setting: Retrospective cohort study in a 24-bed medical-surgical intensive care unit (ICU).
Patients: Forty patients with severe CAP admitted to the ICU from March 2003 and May 2005.
Measurements and results: Random cortisol levels were measured up to 72 h after ICU admission. A threshold of 20 microg/dl was considered for the diagnosis of adrenal insufficiency. Median cortisol levels were 15.5 microg/dl (IQR 10.8-25.1), and 26 patients (65%) met the criteria for adrenal insufficiency. Other cutoff levels of cortisol were evaluated, and 30 patients (75%) had cortisol levels below 25 microg/dl and 19 (47.5%) had cortisol levels below 15 microg/dl. When only patients with septic shock (n=19) were evaluated, 12 (63%) had adrenal insufficiency.
Conclusions: Relative adrenal insufficiency occurs in a high proportion of patients with severe CAP. This finding highlights the importance of measuring cortisol levels and may help explain the potential benefits of hydrocortisone infusion in these patients.