Influence of renal dysfunction on the accuracy of procalcitonin for the diagnosis of postoperative infection after vascular surgery.
OBJECTIVE
Procalcitonin has been advocated as a specific biomarker for bacterial infection. We performed this study to determine whether accuracy of procalcitonin for diagnosis of postoperative bacterial infection is affected by renal function after aortic surgery.


METHODS
Single-center prospective study.


METHODS
University hospital.


METHODS
Two hundred seventy-six patients scheduled for elective major aortic surgery.


METHODS
Blood samples were taken before surgery and each day over the 5-day postoperative period, and measurement of serum procalcitonin was performed. Diagnosis of infection was performed by a blinded expert panel. Renal function was assessed using an estimate of creatinine clearance with the Cockcroft formulas. Renal dysfunction was defined as a creatinine clearance <50 mL x min(-1).


RESULTS
Infection was diagnosed in 67 patients. Seventy five patients (27%) had postoperative renal dysfunction. Procalcitonin was significantly higher in infected patients, with a peak reached at the fourth postoperative day, but it was significantly higher in patients with impaired renal function in both control and infected patients. The optimal threshold of procalcitonin markedly differed in patients with renal dysfunction compared with patients without renal dysfunction (2.57 vs. 0.80 ng x mL(-1), p < .05). The diagnostic accuracy of procalcitonin significantly increased (0.74 vs. 0.70, p < .05) when the threshold of procalcitonin was adapted to the renal function. The elevation of procalcitonin occurred 2 days before the medical team was able to diagnose infection.


CONCLUSIONS
Procalcitonin is a valuable marker of bacterial infections after major aortic surgery, but renal function is a major determinant of procalcitonin levels and thus different thresholds should be applied according to renal function impairment.
Amour
Julien
J
Department of Anesthesiology and Critical Care, Centre Hospitalo-Universitaire Pitié-Salpêtrière, Assitance Publique-Hôpitaux de Paris, Université Pierre et Marie Curie-Paris 6, Paris, France. julien.amour@psl.aphp.fr
Birenbaum
Aurélie
A
Langeron
Olivier
O
Le Manach
Yannick
Y
Bertrand
Michèle
M
Coriat
Pierre
P
Riou
Bruno
B
Bernard
Maguy
M
Hausfater
Pierre
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002116:Calcitonin / Q000097:blood*; D015740:Calcitonin Gene-Related Peptide; D003404:Creatinine / Q000097:blood*; D005260:Female; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000097:blood / Q000175:diagnosis* / Q000517:prevention & control; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood*; D012372:ROC Curve; D018805:Sepsis / Q000097:blood / Q000175:diagnosis* / Q000517:prevention & control; D014656:Vascular Surgical Procedures
D000900:Anti-Bacterial Agents; C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D003404:Creatinine; D015740:Calcitonin Gene-Related Peptide