Evaluation of a handheld creatinine measurement device for real-time determination of serum creatinine in radiology departments.
OBJECTIVE
To assess the feasibility/accuracy of a commercial handheld device in the context of increased demand for point-of-care serum creatinine (SCr) determination.


METHODS
In this institutional review board-approved, prospective study, 401 patients referred for contrast-enhanced computed tomography were included at two centres. Capillary (c)SCr was determined using two devices A+B and venous (v)SCr was determined in the centre's laboratory. Method comparison statistics for both centres and for vSCr<>1.2 mg/dL, receiver operating characteristic analysis, negative predictive values (NPV), sensitivity and specificity were calculated pre-/post-curve offset correction with vSCr.


RESULTS
Pearson's coefficients for cSCr vs vSCr were: centre 1-A:0.93/B:0.92; centre 2-A:0.85/B:0.82 (all P < 0.0001). Overall correlation was better for vSCr > 1.2 mg/dL. The area under the receiver operating characteristic curves showed a high accuracy for cSCr, but the device underestimated SCr, which was confirmed by Bland-Altman plot. Addition of the offset correction factor to the original data from centre 1 resulted in an improvement in sensitivity for detecting patients at risk (> 1.2 mg/dL), whilst maintaining acceptable specificity and improving NPV.


CONCLUSIONS
This study showed the feasibility of SCr determination using the evaluated handheld device in a routine clinical setting. The device showed high sensitivity and high NPV, but may significantly underestimate SCr without offset correction to local laboratories.
Stefan Haneder, Alexandra Gutfleisch, Claudia Meier, Stefan O Schoenberg, Henrik J Michaely, Institute of Clinical Radiology and Nuclear Medicine, University Medical Centre Mannheim, University of Heidelberg, 68167 Mannheim, Germany.
Stefan
S
Haneder
Alexandra
A
Gutfleisch
Claudia
C
Meier
Joachim
J
Brade
Dieter
D
Hannak
Stefan O
SO
Schoenberg
Christoph R
CR
Becker
Henrik J
HJ
Michaely