Serum procalcitonin levels predict acute kidney injury in critically ill patients.

Aim: To determine whether admission procalcitonin (PCT) was associated with the subsequent development of acute kidney injury (AKI) in a general population of critically ill patients.

Methods: The study was a retrospective observational study conducted in a multidisciplinary intensive care unit (ICU) over a period of 1 year. Adult patients who had a PCT performed on admission and who did not have chronic kidney disease (CKD) or AKI on admission, were evaluated for the development of AKI within the first week of ICU admission, according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria. The association between PCT on admission and the development of AKI was explored for the entire cohort and for septic and non-septic subgroups.

Results: Two hundred and one patients were included in the study. The incidence of AKI in the first 7 days of ICU admission was 36.8%. PCT, age, the presence of shock on admission, and sepsis were significantly associated with AKI on univariate analysis. Multivariable analysis of the entire cohort revealed that age, shock and sepsis remained independent predictors of AKI, while PCT was no longer significant. When the septic and non-septic patients were analyzed separately a PCT ≥10 ng/mL remained the only significant predictor of AKI in the non-septic patients (OR 4.430; 95% CI 1.464-13.399), but was not an independent predictor of AKI in septic patients.

Conclusion: The main finding of this study was the significant association of an elevated PCT on admission with the development of AKI in the non-septic patient. An elevated PCT in a non-septic patient identifies a patient at increased risk of AKI. PCT requires further study as a novel biomarker of AKI in non-septic patients.