Background: Serum procalcitonin is commonly used to differentiate systemic inflammation due to infection from non-infectious causes. Limited data exist on the value of procalcitonin in predicting relative adrenal insufficiency (RAI). This study evaluated the value of procalcitonin in predicting RAI and mortality in cirrhotic patients with septic shock.
Methods: This was a post-hoc analysis of a randomized placebo-controlled trial that evaluated low-dose hydrocortisone in cirrhotic patients with septic shock. Extracted first study-day data included serum procalcitonin, baseline serum cortisol, cortisol level after 250 µg - adrenocorticotropic hormone stimulation test and 28 - day mortality. RAI was defined as a baseline serum cortisol < 10 µg/dL or cortisol not rising by > 9 µg/dL after stimulation. Procalcitonin > 0.5 ng/mL was considered high.
Results: Forty-five patients had serum procalcitonin measured (mean = 2.7 ± 3.2 ng/mL, first and third quartiles were 0.3 and 3.3 ng/mL, respectively). Most (78%) patients had high procalcitonin levels. RAI was present in 34 (76%) patients. Patients with high procalcitonin were more likely to have RAI (odds ratio, 4.8; 95% confidence interval, 1.1 - 22.1). Receiver operator characteristic curve analysis showed that the best cut-off for detecting RAI was 1.0 ng/mL (sensitivity = 79% and specificity = 55%). High serum procalcitonin was not associated with 28 - day mortality (80% for normal procalcitonin and 77% for high procalcitonin, p = 0.61).
Conclusions: High serum procalcitonin was highly associated with RAI in cirrhotic patients with septic shock. Procalcitonin was not associated with 28 - day mortality in this patient population.