Capillary electrophoresis/immunosubtraction as a better alternative to immunofixation for detecting and immunotyping serum monoclonal proteins in patients with immunoglobulin light chain (AL) amyloidosis.
Capillary electrophoresis/immunosubtraction (CE/IS) is a simple method for detecting and immunotyping serum or urine monoclonal proteins. To our knowledge, there are no previous reports of the use of CE/IS for characterizing patients with Immunoglobulin light chain (AL) amyloidosis, and there are no convincing data available to compare CE/IS with serum immunofixation electrophoresis (IFE) and free light chain (FLC) assay. The aim of this study was to evaluate the clinical utility of CE/IS in patients with AL amyloidosis as a diagnostic accuracy study. This study included 50 patients with AL amyloidosis (17 newly diagnosed and 33 undergoing treatment). Serum IFE identified monoclonal proteins in 15/50 (30%) of all cases and in 7/17 (41%) of newly diagnosed cases. CE/IS identified monoclonal proteins in 16/50 (32%) of all cases and in 7/17 (41%) of newly diagnosed cases. The FLC assay detected an abnormal ratio of kappa and lambda light chains in 26/50 (52%) of all cases and in 15/17 (88%) of newly diagnosed cases. IFE and CE/IS combined with FLC assay identified monoclonal proteins more sensitive than IFE alone and CE/IS alone, in newly diagnosed patients (p = 0.002 and 0.002, respectively) and in patients undergoing treatment (p = 0.031 and 0.016, respectively). CE/IS is an acceptable alternative to IFE.
a Department of Hematology , Japanese Red Cross Medical Center , Tokyo , Japan.
Kanji
K
Miyazaki
a Department of Hematology , Japanese Red Cross Medical Center , Tokyo , Japan.
Kenshi
K
Suzuki
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D058227:Amyloidogenic Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000686:Amyloidosis / Q000175:diagnosis* / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D015415:Biomarkers / Q000378:metabolism; D019075:Electrophoresis, Capillary / Q000379:methods; D005260:Female; D015870:Gene Expression; D006801:Humans; D007118:Immunoassay / Q000379:methods; D007145:Immunoglobulin kappa-Chains / Q000097:blood / Q000737:chemistry* / Q000235:genetics; D007146:Immunoglobulin lambda-Chains / Q000097:blood / Q000737:chemistry* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D010950:Plasma Cells / Q000378:metabolism / Q000473:pathology; D011446:Prospective Studies; D016019:Survival Analysis
D058227:Amyloidogenic Proteins; D015415:Biomarkers; D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains
Congo red; free light chain; heavy chain; plasma cells; serum protein