I.v. N-acetylcysteine and emergency CT: use of serum creatinine and cystatin C as markers of radiocontrast nephrotoxicity.
OBJECTIVE
The purpose of this study was to assess the effect of i.v. administration of N-acetylcysteine (NAC) on serum levels of creatinine and cystatin C, two markers of renal function, in patients with renal insufficiency who undergo emergency contrast-enhanced CT.


METHODS
Eighty-seven adult patients with renal insufficiency who underwent emergency CT were randomized to two groups. In the first group, in addition to hydration, patients received a 900-mg injection of NAC 1 hour before and another immediately after injection of iodine contrast medium. Patients in the second group received hydration only. Serum levels of creatinine and cystatin C were measured at admission and on days 2 and 4 after CT. Nephrotoxicity was defined as a 25% or greater increase in serum creatinine or cystatin C concentration from baseline value.


RESULTS
A 25% or greater increase in serum creatinine concentration was found in nine (21%) of 43 patients in the control group and in two (5%) of 44 patients in the NAC group (p = 0.026). A 25% or greater increase in serum cystatin C concentration was found in nine (22%) of 40 patients in the control group and in seven (17%) of 41 patients in the NAC group (p = 0.59).


CONCLUSIONS
On the basis of serum creatinine concentration only, i.v. administration of NAC appears protective against the nephrotoxicity of contrast medium. No effect is found when serum cystatin C concentration is used to assess renal function. The effect of NAC on serum creatinine level remains unclear and may not be related to a renoprotective action.
Poletti
Pierre-Alexandre
PA
Department of Radiology, University Hospital of Geneva, 24, rue Micheli-du-Crest, 1211 Genève 14, Switzerland. pierre-alexandre.poletti@hcuge.ch
Saudan
Patrick
P
Platon
Alexandra
A
Mermillod
Bernadette
B
Sautter
Anna-Maria
AM
Vermeulen
Bernard
B
Sarasin
François P
FP
Becker
Christoph D
CD
Martin
Pierre-Yves
PY
D000111:Acetylcysteine / Q000008:administration & dosage*; D058186:Acute Kidney Injury / Q000097:blood / Q000139:chemically induced / Q000517:prevention & control; D000328:Adult; D015415:Biomarkers / Q000097:blood; D003287:Contrast Media / Q000009:adverse effects; D003404:Creatinine / Q000097:blood*; D055316:Cystatin C; D015891:Cystatins / Q000097:blood*; D004632:Emergency Medical Services / Q000379:methods; D005260:Female; D006801:Humans; D007275:Injections, Intravenous / Q000009:adverse effects; D007472:Iohexol / Q000009:adverse effects / Q000031:analogs & derivatives*; D008297:Male; D014057:Tomography, X-Ray Computed / Q000009:adverse effects*; D016896:Treatment Outcome
D015415:Biomarkers; C525030:CST3 protein, human; D003287:Contrast Media; D055316:Cystatin C; D015891:Cystatins; D007472:Iohexol; C038192:iopromide; D003404:Creatinine; D000111:Acetylcysteine