|
|
||||||||
Hematology |
Departments of1 Laboratory Medicine and Pathology, 2 Internal Medicine/Division of Hematology, and 3 Division of Biostatistics, Mayo Clinic College of Medicine, Rochester, MN.
aAddress correspondence to this author at: Department of Laboratory Medicine and Pathology, Hilton Bldg. 210, Mayo Clinic, 200 First St. SW, Rochester, MN 55905. Fax 507-266-4088; e-mail katzmann{at}mayo.edu.
Background: The International Staging System for multiple myeloma has increased the importance of accurate measurement of serum albumin. Two common albumin assays, bromcresol green (BCG) and agarose gel protein electrophoresis (PEL), frequently yield discordant results, creating confusion regarding which assay is superior for use in myeloma.
Methods: We measured albumin by BCG on a Roche Modular system, by PEL with a Helena SPIFE SPE Vis agarose gel, and by immunonephelometry performed on a Dade Behring BNII nephelometer. BCG and PEL were used to measure albumin in 5777 patient samples, and all 3 methods were used in an additional 252 samples. The clinical impact was assessed on 698 myeloma patient samples.
Results: For sera with zero/low monoclonal immunoglobulin protein (M)-spike (0 to <15 g/L), results for both BCG and PEL correlated well to nephelometry, although median PEL results were 8 g/L lower than corresponding BCG measurements. Correlation between PEL and nephelometry or BCG diminished with increasing M-spike, with PEL eventually overestimating albumin compared with both other assays. IgG and IgA M-spikes showed significantly different effects on albumin discordance. For 35% of myeloma patients, discrepancy between BCG and PEL had a potentially clinically significant effect on staging, but no difference in group survival was found.
Conclusions: Both BCG and PEL correlate well to nephelometry in sera with zero/low M-spikes. In the presence of larger M-spikes, PEL correlates poorly to nephelometry or BCG, whereas BCG compares well with nephelometry regardless of M-spike. Thus, albumin measurement can be performed reliably in myeloma patient sera by use of inexpensive, automated BCG assays.
The following articles in journals at HighWire Press have cited this article:
![]() |
D. L. Murray, E. Ryu, M. R. Snyder, and J. A. Katzmann Quantitation of Serum Monoclonal Proteins: Relationship between Agarose Gel Electrophoresis and Immunonephelometry Clin. Chem., August 1, 2009; 55(8): 1523 - 1529. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. M. Quick, A. Klipp, G. L. Woods, J. W. Theus, and J. A. Bornhorst Comparison of Bromcresol Purple and Capillary Protein Electrophoresis for Quantification of Serum Albumin in Multiple Myeloma Clin. Chem., March 1, 2009; 55(3): 594 - 596. [Full Text] [PDF] |
||||
![]() |
P. Kapoor, C. L.H. Snozek, C. Colby, D. R. Larson, J. A. Katzmann, S. V. Rajkumar, and P. R. Greipp Clinical Impact of Discordance in Serum Albumin Measurements on Myeloma International Staging System J. Clin. Oncol., August 20, 2008; 26(24): 4051 - 4052. [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |