The specificity of monoclonal fluorescence polarization immunoassay for cyclosporine in recipients of simultaneous pancreas-kidney transplants.
Simultaneous kidney-pancreas transplant (SPK) recipients have a higher rate of acute organ rejection than do recipients of a kidney-alone transplant. The etiology of this increased number of rejection episodes is unknown. Cyclosporine (CsA) monitoring in SPK recipients is an important tool in the care of these patients. Many centers use the monoclonal fluorescence polarization immunoassay (mFPIA) to monitor CsA levels in this group of organ recipients. The reported specificity of the mFPIA for the CsA parent compound has varied in several studies but has not been systematically studied in recipients of an SPK transplant. Twelve recipients of an SPK transplant from 1 month to 3 months after surgery had serial simultaneous whole blood high-performance liquid chromatography (HPLC) and mFPIA CsA concentrations evaluated. A control group of 15 nondiabetic kidney-alone recipients underwent a similar evaluation. The average mFPIA/HPLC ratio in recipients of an SPK was 1.71 +/- 0.05 (r = 0.94), whereas it was 1.56 +/- 0.03 (r = 0.98) in the kidney-alone group (p > 0.01). Interpatient variability (range, 1.41 to 2.13) was very high in the SPK group, whereas intrapatient variability was lower. Seven patients had AUC profiles. The average AUC mFPIA/HPLC ratio was not significantly different from each patient's respective trough ratios. Our study suggests that the mFPIA overestimates CsA parent compound to a greater extent in SPK recipients than in kidney-alone recipients. In addition, the large interpatient variability in the specificity of the mFPIA makes assessing individual patient's levels problematic.
Kaplan
B
B
Division of Nephrology and Transplantation, Northwestern University Medical School, Chicago, Illinois 60611, USA.
Wang
Z
Z
Keilani
T
T
Kaufman
D B
DB
D000328:Adult; D002851:Chromatography, High Pressure Liquid; D003524:Cyclosporins / Q000008:administration & dosage / Q000009:adverse effects / Q000097:blood* / Q000378:metabolism; D005260:Female; D016231:Fluorescence Polarization Immunoassay; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000097:blood* / Q000378:metabolism; D016030:Kidney Transplantation / Q000276:immunology / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016035:Pancreas Transplantation / Q000276:immunology / Q000379:methods*; D015203:Reproducibility of Results
D003524:Cyclosporins; D007166:Immunosuppressive Agents