Clinical Chemistry Link to Randox Laboratories Web Site
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Clinical Chemistry 36: 804-807, 1990;
This Article
Right arrow Full Text (PDF)
Right arrow Submit an electronic Letter to
the Editor about this paper
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Keown, P. A.
Right arrow Articles by Cameron, E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Keown, P. A.
Right arrow Articles by Cameron, E.

Clinical Chemistry, Vol 36, 804-807, Copyright © 1990 by American Association for Clinical Chemistry

Therapeutic monitoring of cyclosporine: impact of a change in standards on 125I-monoclonal RIA performance in comparison with liquid chromatography

PA Keown, J Glenn, J Denegri, U Maciejewska, D Seccombe, M Stawecki, D Freeman, C Stiller, C Shackleton and E Cameron
British Columbia Transplant Society, Vancouver, Canada.

This study examines the measurement of cyclosporine (CsA) by 125I- monoclonal RIA, and describes the impact of the recent change in the standard curve provided. CsA concentrations in serum and whole-blood control samples measured by 125I-RIA were initially 8-18% higher than those by HPLC. During the first two months of 1989, a significant and sustained deviation in the 125I-RIA produced results that exceeded the HPLC results by 21-28% (P less than 0.001). Introduction of the new standard curve in March 1989 returned the concentration of the whole- blood controls to the previous range (11-12% above HPLC, P less than 0.001). Measurement of clinical samples from heart, liver, and bone- marrow graft recipients by 125I-RIA by both old and new kit standards produced a close linear correlation (y = 0.89 x - 19.02; r = 0.99; n = 75, range = 40-850 micrograms/L), with use of the new standards yielding results 82 (SD 8)% of those with the preceding assay. However, even with the new standard curve, CsA concentrations by 125I-RIA in the clinical samples exceeded those by HPLC by a factor of 1.37 (SD 0.18) to 1.52 (SD 0.19). Segregation for transplant type did not affect the RIA/HPLC ratio. The results suggest cross-reactivity of the 125I-RIA with material present in vivo.




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1990 by the American Association for Clinical Chemistry.