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Jacobs JFM, van der Molen RG, Keren DF. Relatively restricted migration of polyclonal IgG4 may mimic a monoclonal gammopathy in IgG4-related disease. Am J Clin Pathol 2014; 142:76-81. [PMID: 24926089 DOI: 10.1309/ajcp41xcvbheqcel] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVES IgG4-related disease (IgG4-RD) is an increasingly recognized syndrome of unknown etiology that can affect a wide variety of organs. The commonly shared features include tumor-like swelling of the involved organs, a lymphoplasmacytic infiltrate enriched with polyclonal IgG4-positive plasma cells, variable degree of fibrosis, and elevated serum concentrations of polyclonal IgG4. METHODS In a qualitative retrospective study, the electrophoretic characteristics of serum from patients with increased polyclonal IgG4 were studied to see if a reproducible pattern could be identified. RESULTS We demonstrate that a characteristic focal band bridging the β and γ fraction by serum protein electrophoresis may be a first serologic indication for IgG4-RD. We further demonstrate that significant κ:λ skewing can occur in the polyclonal IgG4 fraction. CONCLUSIONS The focal band detected by electrophoresis in sera from patients with IgG4-RD can be confirmed as polyclonal by immunofixation or immunosubtraction. Because these bands may be predominately of one light chain isotype, they could be misinterpreted as monoclonal gammopathies.
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Keren DF, Shalhoub R, Gulbranson R, Hedstrom D. Expression of hemoglobin variant migration by capillary electrophoresis relative to hemoglobin A2 improves precision. Am J Clin Pathol 2012; 137:660-4. [PMID: 22431544 DOI: 10.1309/ajcpof8v0jjopsvf] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
We report the precision of the mean migration position of hemoglobin (Hb)S, HbC, HbG (Philadelphia), and HbD (Los Angeles) in 193 samples of whole blood assayed by capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC). By expressing the migration of Hb variants by CE relative to that of HbA(2) in the same sample, there was a significant improvement in the coefficient of variation for each variant studied. The potential usefulness of expressing Hb variants relative to that of HbA(2) was evaluated by comparing the separation of 2 closely migrating Hbs. When expressed by their initial migrations on CE, 25 of the 43 cases of HbG and HbD overlapped. However, when the migrations of these variants were expressed relative to the HbA(2) in the same sample, the 24 cases of HbG separated completely from the 19 cases of HbD. These findings suggest that expressing Hb variants relative to an internal standard, such as HbA(2), may be of value for establishing a library of variant Hbs evaluated by CE.
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Keren DF, Sample LR. Accounting for artifactually elevated HbA2 in cases of Hb hope when measured by capillary electrophoresis. Am J Clin Pathol 2011; 136:996-7; author reply 997-8. [PMID: 22095384 DOI: 10.1309/ajcpn5zfb6mdcokw] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022] Open
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Keren DF. Commentary. Clin Chem 2011; 57:951-2. [DOI: 10.1373/clinchem.2011.162669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Valenstein PN, Alpern GA, Keren DF. Responding to large-scale testing errors. Am J Clin Pathol 2010; 133:440-6. [PMID: 20154282 DOI: 10.1309/ajcpxlze0yynid0x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
Extensive use of automation in the clinical laboratory creates the potential for systematic errors that affect a large number of patient results before the error is discovered. When a large-scale testing error is found, the approaches recommended for responding to individual medical mishaps are often inadequate. This report uses 2 case studies to illustrate some of the unique challenges facing laboratory managers confronted with a large-scale testing error. We identify 9 distinct constituencies that may be impacted by large-scale testing errors, each of which requires laboratory management's thoughtful and timely attention.
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Mais DD, Gulbranson RD, Keren DF. The range of hemoglobin A(2) in hemoglobin E heterozygotes as determined by capillary electrophoresis. Am J Clin Pathol 2009; 132:34-8. [PMID: 19864231 DOI: 10.1309/ajcpp50jixxzvlss] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Capillary electrophoresis (CE) is capable of distinguishing hemoglobin E (HbE) from hemoglobin A(2) (HbA(2)), thus permitting quantification of HbA(2) in patients with HbE. In this study, routine samples submitted for evaluation of hemoglobinopathy that demonstrated HbE were studied by high-pressure liquid chromatography and CE. The data for 52 samples from adult HbE heterozygotes were compared with those for a control group consisting of 209 patients. The mean HbA(2) of patients with HbE trait was 3.4% (SD, 0.4%), which was significantly higher (P < .001) than the 2.6% (SD, 0.4%) for the control group. Seven samples from adults homozygous for HbE were also evaluated. The mean HbA(2) of HbE homozygotes was 4.4%, which was significantly greater (P < .001) than the HbA(2) values for the HbE heterozygotes. Data from these cases provide an estimate of the range of HbA(2) in patients with HbE when evaluated by CE.
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Keren DF. Commentary. Clin Chem 2009. [DOI: 10.1373/clinchem.2008.118596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Keren DF, Hedstrom D, Gulbranson R, Ou CN, Bak R. Comparison of Sebia Capillarys capillary electrophoresis with the Primus high-pressure liquid chromatography in the evaluation of hemoglobinopathies. Am J Clin Pathol 2008; 130:824-31. [PMID: 18854277 DOI: 10.1309/ajcpqy80hzwhhgzf] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
The Sebia Capillarys (capillary zone electrophoresis [CE]) and the Primus Resolution high-pressure liquid chromatography (HPLC) were used to prospectively evaluate 297 samples for hemoglobinopathies. Hemoglobin (Hb) A levels were similar on both techniques (mean, 96.2% and SD, 5.7% by CE; mean, 96.8% and SD, 5.5% by HPLC), but HbA2 levels were higher by CE (mean, 2.8%; SD, 0.8%) than by HPLC (mean, 2.3%; SD, 0.8%). HbS had higher values by CE (mean, 40.6%; SD, 18.9%) than by HPLC (mean, 38.4%; SD, 18.9%). In cases with Hg S, HbA2 levels were greater by HPLC (mean, 4.0%; SD, 1.0%) than by CE (mean, 3.1%; SD, 0.8%). HbA2 was occasionally not separated sufficiently from HbC for measurement by CE, but did separate from HbE by CE. Both methods identified HbS, HbC, HbE, HbS, and HbC together, HbA2&prime, HbD-Los Angeles, HbF variant, HbG-Philadelphia, HbS-G Philadelphia, and Hb Lepore.
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Mais DD, Boxer LA, Gulbranson RD, Keren DF. Hemoglobin Ypsilanti: a high-oxygen-affinity hemoglobin demonstrated by two automated high-pressure liquid chromatography systems. Am J Clin Pathol 2007; 128:850-3. [PMID: 17951209 DOI: 10.1309/wae8jnk656cqaql5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Hemoglobin (Hb) Ypsilanti is a rare high-oxygen-affinity hemoglobin. Like other high-oxygen-affinity hemoglobins, Hb Ypsilanti manifests as erythrocytosis. Because the migration of many high-oxygen-affinity variants on alkaline and acid gels does not differ from that of HbA, oxygen-hemoglobin dissociation studies are often used to document their presence. Hb Ypsilanti is a notable exception because its electrophoresis pattern on alkaline gel is highly characteristic, exemplifying the phenomenon of hybrid formation in variant hemoglobins. In the past few years, several laboratories have begun to use high-pressure liquid chromatography (HPLC) as a screen for hemoglobinopathies. We demonstrate the elution profile of Hb Ypsilanti on the 2 most widely used HPLC methods.
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Hayes MJ, Carey JL, Krauss JC, Hedstrom DL, Gulbranson RL, Keren DF. Low IgE monoclonal gammopathy level in serum highlights 20-yr survival in a case of IgE multiple myeloma. Eur J Haematol 2007; 78:353-7. [PMID: 17378894 DOI: 10.1111/j.1600-0609.2007.00825.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
This report describes the diagnosis, follow-up, and problems measuring serum immunoglobulin E (IgE) levels in a case of IgE myeloma with 20-yr survival. Serum and urine protein electrophoresis, immunofixation, and the N Latex IgE test were used to characterize the monoclonal proteins. The diagnosis of multiple myeloma in a 56-yr-old man was based on 5.4 g/24 h of monoclonal free lambda chain in urine and bone marrow findings of 23.5% plasma cells (19% mature and 4.5% atypical). IgE lambda monoclonal protein in serum measured 506,000 microg/L (210 833 IU/mL). The lack of other clinical findings of multiple myeloma places this case in the category of 'smoldering or indolent myeloma'. Measurement of serum IgE levels was complicated by the need to predilute serum to avoid antigen excess. Following chemotherapy, the patient went into clinical remission, eventually dying of complications of emphysema. This case expands the recognized clinical spectrum of IgE multiple myeloma.
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Lambert-Messerlian GM, Keren DF, Raphtis CS, Byberg K, Canick JA. Apparently low maternal serum inhibin A levels in second-trimester screening. Prenat Diagn 2005; 25:967-8. [PMID: 16193465 DOI: 10.1002/pd.1279] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Bakshi NA, Gulbranson R, Garstka D, Bradwell AR, Keren DF. Serum free light chain (FLC) measurement can aid capillary zone electrophoresis in detecting subtle FLC-producing M proteins. Am J Clin Pathol 2005; 124:214-8. [PMID: 16040291 DOI: 10.1309/xe3u-dark-w1b9-emwm] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2022] Open
Abstract
We hypothesized that using a free light chain (FLC) assay as an adjunct to capillary zone electrophoresis (CZE) could improve detection of lymphoplasmacytic processes. We prospectively studied 1,003 consecutive serum samples submitted for routine protein electrophoresis and/or immunofixation electrophoresis by CZE and FLC. Samples from patients previously characterized as having M proteins were excluded. Protein electrophoresis was read by a pathologist unaware of the FLC results. Sixteen cases revealed an abnormal free kappa/lambda ratio in which CZE did not demonstrate an M protein. Nine cases of B-lymphocyte or plasma cell proliferative processes were detected by an abnormal free kappa/lambda ratio in which CZE did not demonstrate an M protein. Cases with low free kappa/lambda ratios included 1 chronic lymphocytic leukemia (CLL), 1 IgM lambda with aplastic anemia, and 1 lambda light chain myeloma. Cases with high free kappa/lambda ratios included 2 CLL, 1 lymphocytosis (possibly early CLL), 1 kappa light chain myeloma, 1 atypical lymphoma with neuropathy, and 1 nonsecretory myeloma. Addition of the free kappa/lambda ratio to CZE increases the yield of lymphocyte and plasma cell proliferative processes detected by 56%.
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Bakshi NA, Gulbranson R, Garstka D, Bradwell AR, Keren DF. Serum Free Light Chain (FLC) Measurement Can Aid Capillary Zone Electrophoresis in Detecting Subtle FLC-Producing M Proteins. Am J Clin Pathol 2005. [DOI: 10.1309/xe3udarkw1b9emwm] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Keren DF. Speak out for quality pathology and laboratory medicine. Am J Clin Pathol 2004; 122:314. [PMID: 15323149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023] Open
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Keren DF, Gulbranson R, Ebrom SJ. False-Negative Urine Protein Electrophoresis by Semiautomated Gel Electrophoresis. Clin Chem 2004; 50:933-4. [PMID: 15105351 DOI: 10.1373/clinchem.2003.029199] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Keren DF. Leading the way for laboratory week. Am J Clin Pathol 2004; 121:600. [PMID: 15080314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023] Open
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Keren DF. You can be an ASCP advocate. Am J Clin Pathol 2004; 121:437. [PMID: 15023049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023] Open
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Keren DF. Optimizing Detection of Oligoclonal Bands in Cerebrospinal Fluid by Use of Isoelectric Focusing With IgG Immunoblotting. Am J Clin Pathol 2003. [DOI: 10.1309/vgahdtdn3n5qmxuc] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Keren DF. Optimizing detection of oligoclonal bands in cerebrospinal fluid by use of isoelectric focusing with IgG immunoblotting. Am J Clin Pathol 2003; 120:649-51. [PMID: 14608888 DOI: 10.1309/vgah-dtdn-3n5q-mxuc] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023] Open
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Abstract
The ANA test is an excellent screening test for patients with SLE and a few other connective tissue diseases. The LE cell preparation is an assay that is subjective and costly. Because of the presence of a superior screening test (the ANA) and superior specific auto-antibody tests, the author recommends that the use of LE cell preparations be discontinued. ANA screening tests may be performed either by indirect microscopic serology (usually IFA) or EIA. The latter technique is readily automated and many new products for this screening test have appeared in the past decade. The products differ, however, and laboratories are cautioned to test each in the context of the clinical needs of their clinicians. Proper use of the ANA test requires each laboratory to determine the cutoff used under their conditions of assay. Although either ANA screening test has a high negative predictive value in numerous studies, proper selection of patients to be tested is key to improving the predictive value of a positive result. The American College of Rheumatism criteria are reviewed and recommended as part of the patient selection process for this testing.
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Martin CA, Keren DF. Comparison of murex single-use diagnostic system with traditional enzyme immunoassay for detection of exposure to human immunodeficiency virus. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2002; 9:187-9. [PMID: 11777853 PMCID: PMC119866 DOI: 10.1128/cdli.9.1.187-189.2002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Because a retrospective study detected 13 negative Western blots out of 38 single-use diagnostic system (SUDS)-positive cases over a 1-year period, we performed a prospective study to compare the performance of the SUDS test with that of enzyme immunoassay (EIA). Of 888 SUDS-tested sera, 875 (98.4%) were both SUDS and EIA negative and 5 (0.6%) were SUDS, EIA, and Western blot positive. The rate of SUDS-positive samples decreased from 3.16/month in the retrospective study to 1.33/month in the prospective study. The immunoassays had sensitivities and specificities of 100 and 99.7 (SUDS) and 100 and 99.4% (traditional EIA), respectively. In laboratories with experienced personnel, the SUDS test performs as well as the EIA as a screen for infection with the human immunodeficiency virus.
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Keren DF, Gulbranson R, Carey JL, Krauss JC. 2-Mercaptoethanol treatment improves measurement of an IgMkappa M-protein by capillary electrophoresis. Clin Chem 2001; 47:1326-7. [PMID: 11427473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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Keren DF, Gulbranson R, Carey JL, Krauss JC. 2-Mercaptoethanol Treatment Improves Measurement of an IgMκ M-Protein by Capillary Electrophoresis. Clin Chem 2001. [DOI: 10.1093/clinchem/47.7.1326] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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McCoy JP, Keren DF. Current practices in clinical flow cytometry. A practice survey by the American Society of Clinical Pathologists. Am J Clin Pathol 1999; 111:161-8. [PMID: 9930136 DOI: 10.1093/ajcp/111.2.161] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The American Society of Clinical Pathologists surveyed 136 laboratories actively engaged in performing clinical flow cytometric testing to determine the demographics of these laboratories, the credentials of the personnel involved with testing, the volume and types of tests performed, and how data are analyzed and interpreted. These results are reported with commentary based on previous surveys and recommended practice guidelines.
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