Quantification of β-region IgA monoclonal proteins – should we include immunochemical Hevylite® measurements? Point

2016 ◽  
Vol 54 (6) ◽  
Author(s):  
Josie A.R. Evans ◽  
Ellen L. Jenner ◽  
Hugh D. Carr Smith ◽  
Oscar Berlanga ◽  
Stephen J. Harding
Keyword(s):  
Light Chain ◽  
Residual Disease ◽  
Response Assessment ◽  
Protein Electrophoresis ◽  
Monoclonal Protein ◽  
Laboratory Staff ◽  
Additional Information ◽  
Significant Challenge ◽  
Alternative Methodology ◽  
Monoclonal Proteins

AbstractAccurate measurement of IgA monoclonal proteins presents a significant challenge to laboratory staff. IgA heavy/light chain (Hevylite, HLC) analysis is an alternative methodology for monoclonal protein assessment, giving an independent measure of IgAκ and IgAλ concentrations. Clonality is assessed by calculating the ratio of involved immunoglobulin to background uninvolved immunoglobulin concentrations (e.g. IgAκ/IgAλ in an IgAκ patient). Here we discuss the challenges faced by the laboratory in IgA monoclonal protein assessment, and compare the performance of Hevylite assays with electrophoresis and total IgA results. We present data which validates the use of Hevylite for response assessment: in most cases, Hevylite provides comparable response assignment to that provided by serum protein electrophoresis (SPE) and total IgA; in other cases Hevylite provides additional information, such as detection of residual disease or relapse.

Impact of Normalized Free Light Chain Ratio for Assessment of Monoclonal Protein in Patients with Light Chain Only and Oligosecretory Myeloma

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2074-2074
Author(s):  
Kentaro Narita ◽  
Yoshiaki Usui ◽  
Yoshiaki Abe ◽  
Masami Takeuchi ◽  
Kosei Matsue
Keyword(s):  
Light Chain ◽  
Urine Analysis ◽  
Residual Disease ◽  
Response Assessment ◽  
Protein Electrophoresis ◽  
Free Light Chain ◽  
Reference Ranges ◽  
Immunofixation Electrophoresis ◽  
The Impact ◽  
Monoclonal Component

Abstract Background: Monitoring of serum free light chain (sFLC) ratio after treatment in multiple myeloma (MM) patients is valuable for assessing monoclonal component of free light chain (FLC). However, the recent International Myeloma Working Group guidelines did not recommend replacing 24-hour urine analysis with FLC analysis in diagnosis or response assessment of MM, and previous studies indicated discordance between urine analysis and sFLC levels in light chain-only MM (LCMM). This is clinically relevant because sFLC normalization was considered a surrogate for improved outcome in both LCMM and intact immunoglobulin MM (IIMM). The clinical impact of FLC ratio normalization on detection of monoclonal component may differ between LCMM or oligosecretory myeloma (OSMM) and IIMM. This study explored the utility of sFLC ratio as a surrogate for residual clonal monoclonal component compared with 24-hour urine immunofixation electrophoresis (uIFx) after treatment. We evaluated the impact of normalization of sFLC ratio in patients with LCMM/OSMM that obtained very good partial response (VGPR), complete response (CR), and immunophenotypic CR (iCR; sIFx/uIF negative plus ≤ 10-4 clonal PCs) determined by multicolor flow cytometry (MFC). Methods: We included 176 patients (51 with LCMM and OSMM, 125 with IIMM) treated between April 2006 and January 2016 at Kameda Medical Center, Japan. Immunoglobulin levels in serum and urine samples were examined by serum protein electrophoresis (SPEP), serum immunofixation electrophoresis (sIFx), urine protein electrophoresis (UPEP), uIFx, and sFLC for response assessment. Minimal residual disease (MRD) assessments after treatment were performed by 6-color MFC and the results were compared to other tests of monoclonal components, including SPEP, UPEP, sIFx, uIFx, and FLC. Agreement between sFLC normalization and MRD by MFC was assessed using kappa statistic. Disease response was evaluated using IMWG criteria. sFLC was measured by Fleelite® assay (The Binding Site Group Ltd.). Reference ranges for sFLC have been previously published. Statistical analyses were performed with EZR, which is a graphical user interface for R ver. 3.2.1. Ethical considerations: This study was approved by the local ethics committee and conducted in accordance with the Declaration of Helsinki and Good Clinical Practice Guidelines. Results: All of 51 LCMM/OSMM patients (100%) and 95 of the 125 IIMM patients (72%) had measurable and abnormal involved sFLC (≥ 100 mg/L) and positive uIFx at presentation. VGPR, CR, and iCR were obtained in 31 (61%), 25 (49%), and 14 (27%) patients with LCMM/OSMM, respectively, and normalization of sFLC ratio at VGPR, CR and iCR was seen in 1/31 (3%), 13/25 (48%), and 8/14 (57%) of these patients, respectively. Among the LCMM/OSMM patients with iCR, 4 patients obtained deeper iCR (≤ 10-5 clonal PCs) and all of them had normal sFLC ratio, while sFLC ratio remained abnormal in the rest of 10 iCR patients that did not achieve deeper iCR. In IIMM patients, VGPR, CR, and iCR were obtained in 78 (61%), 52 (42%), and 20 (16%) patients, respectively. In contrast to the LCMM/OSMM patients, normalization of the sFLC ratio at VGPR, CR, and iCR was seen in 52/78 (67%), 39/52 (75%), and 17/20 (85%) of IIMM patients, respectively. Thirteen of the 14 IIMM patients (93%) that obtained deeper iCR had normal sFLC ratio. Among the patients with IIMM, percentage of patients with normalized sFLC ratio did not differ between the response groups (p=0.11), while it was significantly different in LCMM/OSMM patients (p<0.001) (Figure 1). These observations indicated that the normalization of sFLC ratio is significantly associated with deeper response in LCMM/OSMM patients, but not in IIMM patients. Conclusions: Our observations indicated that sFLC test has greater sensitivity than urine immunofixation for detection of the monoclonal component of sFLC, especially in patients with LCMM/OSMM. In addition, we also showed that normalization of sFLC ratio is correlated with the depth of response assessed by MFC in patients with LCMM/OSMM, but not in IIMM patients. These findings suggest that FLC ratio provides greater sensitivity for residual disease monitoring than uPEP or uIFx in patients with LCMM and OSMM, and therefore could be considered as an alternative to urine analysis for monitoring of LCMM/OSMM patients. Disclosures No relevant conflicts of interest to declare.

Serum Free Kappa to Free Lambda Ratios as an Adjunct to Serum Protein Electrophoresis for the Detection of Monoclonal Proteins in the Serum.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4856-4856
Author(s):  
Arthur R. Bradwell ◽  
Jean Garbincius ◽  
Earle W. Holmes
Keyword(s):  
Serum Protein ◽  
Light Chain ◽  
Protein Electrophoresis ◽  
Free Light Chain ◽  
Serum Protein Electrophoresis ◽  
Serum Free ◽  
Monoclonal Protein ◽  
Serum Free Light Chain ◽  
Monoclonal Proteins

Abstract Serum free light chain measurements have been shown to be useful in the diagnosis and monitoring of patients with monoclonal gammopathies. The present study was undertaken to evaluate the effect of adding the measurement of serum free light chain kappa to lambda ratios to the serum protein electrophoresis evaluation that we typically use as an initial screen for the detection of monoclonal proteins. We retrospectively tested 347 consecutive samples from individuals who had no previous history of plasma cell dyscrasia and had not previously had a serum or urine electrophoresis or immunofixation electrophoresis test at our institution. The quantitative serum protein electrophoresis test that was ordered was performed using Hydragel Beta 1- Beta 2 gels and Hydrasis instrument (Sebia, Inc., Norcross, GA). The protein content of the electrophoresis zones were quantitated by scanning densitometry and the electrophoresis pattern of each sample was qualitatively examined for abnormal bands and suspicious findings by a single, experienced observer. Serum free light chain concentrations and the serum free light chain kappa to lambda ratios were determined using the Freelite Human Kappa and Lambda Kits (The Binding Site Ltd, Birmingham, UK) and the Immage analyzer (Beckman Coulter Inc., Brea, CA). The serum free light chain kappa to lambda ratios were outside the reference interval (0.25 to1.65) in 23 of the samples. Ten abnormal ratios were observed among a group of 57 samples that had either positive or suspicious qualitative evaluations for the presence of a restriction or that demonstrated hypo-gammaglobulinemia. Both abnormalities led to recommendations for follow-up testing, which confirmed the presence of a monoclonal protein in 21 of the samples. Six abnormal ratios were observed among a group of 159 specimens that had quantitative abnormalities in albumin or one or more of globulin fractions (hypo-gammaglobulinemia excepted) and normal qualitative evaluations. Seven abnormal ratios were observed among a group of 131 samples that had normal quantitative results and normal qualitative evaluations. Follow-up testing is not usually recommended for serum protein electrophoresis results like those in the latter two groups. We found that the addition of the serum free light chain kappa to lambda ratio to the serum protein electrophoresis test increased the number of abnormal screens that would have required further clinical and/or laboratory evaluation by 23%(i.e. from 57 to 70). Given the high specificity of the serum free light chain kappa to lambda ratio for monoclonal light chains, the additional 13 abnormal samples identified by this test are expected to have a high likelihood of harboring a monoclonal protein that would have otherwise eluded detection. Pending a definitive prospective study, we estimate that the addition of a serum free light chain kappa to lambda ratio to the serum protein electrophoresis screen would increase the rate of detection of serum monoclonal proteins by as much as 1.6-fold.

Immunoglobulin Heavy/Light Chain Ratios as An Alternative to Immunofixation In the Identification of Monoclonal Gammopathies

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 5018-5018
Author(s):  
Anandram Seetharam ◽  
Tracy Lovatt ◽  
Alan Macwhannell ◽  
Abe Jacob ◽  
Sunil Honda ◽  
...  
Keyword(s):  
Light Chain ◽  
Hematological Malignancies ◽  
Protein Electrophoresis ◽  
Free Light Chain ◽  
Low Risk ◽  
Close Monitoring ◽  
Haematological Malignancies ◽  
Monoclonal Protein ◽  
M Proteins ◽  
Monoclonal Proteins

Abstract Abstract 5018 Introduction Historically, serum protein electrophoresis (SPE), urine protein electrophoresis (UPE) and immunofixation (IFE) have been used to identify and quantify monoclonal proteins (M-proteins). Whilst this approach is adequate for the identification of intact immunoglobulin multiple myeloma (MM), it is not sensitive enough to detect free light chain MM (LCMM). Therefore, an algorithm which utilises SPE, serum free light chain (FLC) immunoassays and IFE for the identification of M-proteins has been suggested. Assays have now been developed which utilise polyclonal antisera raised against the kappa and lambda light chain types of IgG, IgA and IgM immunoglobulins (HLC). Here we report the use of these assays as an alternative to IFE and propose a screening algorithm which utilises SPE, FLC and HLC Materials and Methods Serum FLC measurement was added to 1063 requests for SPE, from primary care or from a hospital source. Samples from patients with previously diagnosed MM, Waldenstrom's Macroglobulinemia and lymphoma were, where possible, removed. Sera showing monoclonal proteins or hypogammaglobulinemia (by SPE) or an abnormal FLC ratio were tested further by IFE and IgG, IgA, IgM HLC assays. SPE and IFE were performed on a SEBIA Hydrasys system, and gels were interpreted by experienced clinical chemists. FLC and HLC measurements were performed on a Siemens BN™II nephelometer. HLC results were compared with IFE results and clinical diagnoses. The study was approved by the Wolverhampton, New Cross, NHS Trust Review Board Results 80/1063 patients were identified as having abnormal SPE or abnormal FLC results. 42/80 patients had positive IFE results. 24/42 of these patients were positive by HLC (Table 1), 11/42 had light chain only myeloma/MGUS, the remaining 7/42 were MGUS patients. The 7 MGUS patients (6 IgG and 1 IgM) with normal HLC ratios and positive IFE all had less than 2g/L monoclonal protein measured by SPE densitometry and a normal FLC ratio. Of the 38/80 with normal IFE's all had been investigated further because of abnormal FLC results. 9/38 had abnormal HLC ratios of which 3/9 had confirmed hematological malignancies (1× chronic lymphocytic leukemia (CLL), 1× small lymphocytic lymphoma (SLL) and 1× asymptomatic MM (ASMM)). The use of FLC immunoassays alongside SPE as part of the primary screening protocol identified 10 additional hematological malignancies (1× ASMM, 6×CLL, 2× non-Hodgkin lymphoma, 1× SLL). Discussion HLC ratio analysis matched IFE for the identification of all symptomatic haematological malignancies. Abnormal FLC ratios identified 10 additional haematological malignancies of which 3 also had abnormal HLC ratios, which would have been missed using SPE/ IFE. In 7/19 MGUS (6×IgG, 1×IgM) patients there were normal HLC ratios. In all cases the monoclonal protein load was below 2g/L and the FLC ratio was normal; identifying the IgG patients as having a low risk and the IgM patient as having a low/intermediate risk of progression. It may be beneficial not to identify these patients, who do not require therapeutic intervention or justify close monitoring. Another advantage of using HLC analysis instead of IFE is that the HLC ratio has been found to be a prognostic indicator in myeloma and MGUS. It would also form a useful “baseline” comparison if HLC assays were used in monitoring or for the detection of residual disease. Conclusions HLC analysis identified all symptomatic patients who were IFE positive and in an additional 3 hematological malignancies. Low risk MGUS patients may not be identified using these tests but this might be beneficial to patients and physicians alike Disclosures: Harding: Binding Site Group Ltd: Employment.

scholarly journals Quantitative Immunoprecipitation Free Light Chain Mass Spectrometry (QIP-FLC-MS) Simplifies Monoclonal Protein Assessment and Provides Added Clinical Value in Systemic AL Amyloidosis

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4375-4375 ◽  
Author(s):  
Faye Amelia Sharpley ◽  
Hannah Victoria Giles ◽  
Richa Manwani ◽  
Shameem Mahmood ◽  
Sajitha Sachchithanantham ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Light Chain ◽  
Residual Disease ◽  
Renal Involvement ◽  
Light Chains ◽  
Al Amyloidosis ◽  
Free Light Chains ◽  
Accurate Identification ◽  
Monoclonal Protein ◽  
Serum And Urine

Introduction Early diagnosis, effective therapy and precise monitoring are central for improving clinical outcomes in systemic light chain (AL) amyloidosis. Diagnosis and disease response assessment is primarily based on the presence of monoclonal immunoglobulins and free light chains (FLC). The ideal goal of therapy associated with best outcomes is a complete responses (CR), defined by the absence of serological clonal markers. In both instances, detection of the monoclonal component (M-component) is based on serum FLC assessment together with traditional serum and urine electrophoretic approaches, which present inherent limitations and lack sensitivity particularly in AL where the levels are typically low. Novel mass spectrometry methods provide sensitive, accurate identification of the M-component and may prove instrumental in the timely management of patients with low-level amyloidogenic light chain production. Here we assess the performance of quantitative immunoprecipitation FLC mass spectrometry (QIP-FLC-MS) at diagnosis and during monitoring of AL amyloidosis patients treated with bortezomib-based regimens. Methods We included 46 serial patients with systemic AL amyloidosis diagnosed and treated at the UK National Amyloidosis Centre (UK-NAC). All patients had detailed baseline assessments of organ function and serum FLC measurements. Baseline, +6- and +12-month serum samples were retrospectively analysed by QIP-FLC-MS. Briefly, magnetic microparticles were covalently coated with modified polyclonal sheep antibodies monospecific for free kappa light chains (anti-free κ) and free lambda light chains (anti-free λ). The microparticles were incubated with patient sera, washed and treated with acetic acid (5% v/v) containing TCEP (20 mM) in order to elute FLC in monomeric form. Mass spectra were acquired on a MALDI-TOF-MS system (Bruker, GmbH). Results were compared to serum FLC measurements (Freelite®, The Binding Site Group Ltd), as well as electrophoretic assessment of serum and urine proteins (SPE, sIFE, UPE and uIFE). Results Cardiac (37(80%) patients) and renal (31(67%) patients) involvement were most common; 25(54%) patients presented with both. Other organs involved included liver (n=12), soft tissue (n=4), gastrointestinal tract (n=3) and peripheral nervous system (n=2). Baseline Freelite, SPE, sIFE and uIFE measurements identified a monoclonal protein in 42(91%), 22(48%), 34(74%) and 21(46%) patients, respectively. A panel consisting of Freelite + sIFE identified the M-component in 100% of the samples. QIP-FLC-MS alone also identified an M-component in 100% of the samples and was 100% concordant with Freelite for typing the monoclonal FLC (8 kappa, 34 lambda). In 4 patients, QIP-FLC-MS identified an additional M-protein that was not detected by the other techniques. In addition, 4/8(50%) kappa and 4/38(11%) lambda patients showed a glycosylation pattern of monoclonal FLCs at baseline by mass spectrometry. Interestingly, the frequency of renal involvement was significantly lower for patients with non-glycosylated forms (25% vs 76%, p=0.01), while no similar relationship was found for any other organs. During the 1-year follow-up period, 17 patients achieved a CR; QIP-FLC-MS identified serum residual disease in 13(76%) of these patients. Conclusion In our series, QIP-FLC-MS was concordant with current serum methods for identifying the amyloidogenic light chain type and provided, against all other individual tests, improved sensitivity for the detection of the monoclonal protein at diagnosis and during monitoring. The ability to measure the unique molecular mass of each monoclonal protein offers clone-specific tracking over time. Glycosylation of free light chains is over-represented in AL patients which may allow earlier diagnosis and better risk-assessment of organ involvement. Persistence of QIP-FLC-MS positive M component in patients otherwise in CR may allow targeted therapy. Overall, QIP-FLC-MS demonstrates potential to be exploited as a single serum test for precise serial assessment of monoclonal proteins in patients with AL amyloidosis. Disclosures Wechalekar: GSK: Honoraria; Janssen-Cilag: Honoraria; Amgen: Research Funding; Takeda: Honoraria; Celgene: Honoraria.

Correlation of Serum Free Light Chain Levels with Other Parameters in Myeloma.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 5019-5019
Author(s):  
Regina Stein ◽  
Jayesh Mehta ◽  
Eric Vickrey ◽  
William Resseguie ◽  
Seema Singhal
Keyword(s):  
Light Chain ◽  
Poor Correlation ◽  
Serum Free ◽  
Monoclonal Protein ◽  
Additional Information ◽  
Serum Free Light Chain ◽  
Light Chain Disease ◽  
Total Light ◽  
Plasma Cell Dyscrasias ◽  
Anuric Renal Failure

Abstract Estimation of serum free light chains (SFLC; SFKLC - kappa, SFLLC - lambda, SFKLR - kappa:lambda ratio; normal 0.26–1.65.) is useful in selected patients with non-secretory myeloma, and in light chain disease with anuric renal failure. Its utility in other clinical situations is unclear. 489 SFLC levels in 135 myeloma patients were analyzed to see if there was a significant correlation between them and other, more conventional immunologic parameters such as serum total light chain (STLC; STKLC - kappa, STLLC - lambda) levels and immunoglobulin (Ig) levels. The underlying premise was that lack of significant correlation would suggest potential value of SFLC independent of standard tests, whereas significant correlation would suggest questionable independent value of SFLC. The table below shows SFLC and STLC levels and ratios. Parameter Median (range) Correlation with SFKLC Correlation with SFLLC Correlation with free k:l ratio SFKLC 14.4 (0.59–11525) SFLLC 18.2 (0.72–10100) Free k:l ratio 0.83 (0–1211.76) STKLC 745 (11–8810) r=0.08; P=0.07 STLLC 256 (11.6–11000) r=0.11; P=0.01 Total k:l ratio 2.51 (0–245) r=0.12; P=0.008 Poor correlation between free and total results within each light chain subtype (Figure 1 - log scale) and between free and total ratios (Figure 2- log scale) suggests that SFLC values provide information that is independent of STLC values because STLC values cannot be used to predict SFLC values. Figure Figure Figure Figure The table below shows correlation between Ig and SFLC/STLC levels. For these analyses, the total Ig of the specific heavy chain subtype and SFLC/STLC of the specific light chain subtype were studied (IgG and SFKLC with IgG kappa monoclonal protein, IgA and STLLC with IgA lambda monoclonal protein, etc). Very strong correlation between STLC and Ig levels suggests that STLC values do not provide information that is independent of Ig levels. On the other hand, poor correlation between SFLC and Ig levels suggests that SFLC values do provide information that is independent of Ig values. Monoclonal protein SFLC correlation STLC correlation IgG kappa r=0.04; P=0.66 r=0.89; P&lt;0.0001 IgG lambda r=0.13; P=0.51 r=0.99; P&lt;0.0001 IgA kappa r=0.49; P=0.004 r=0.77; P&lt;0.0001 IgA lambda r=-0.04; P=0.89 r=0.94; P&lt;0.0001 These data show that SFLC estimation provides information that is independent of standard quantitative serologic tests used in plasma cell dyscrasias. However, rigorous prospective evaluation of the test is needed to see if this additional information is of any clinical relevance in settings other than non-secretory disease and light chain disease with anuria.

Free Light Chains, Monoclonal Proteins, and Chronic Lymphocytic Leukemia.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4697-4697 ◽  
Author(s):  
Rosa Ruchlemer ◽  
Constantine Reinus ◽  
Esther Paz ◽  
Ahuva Cohen ◽  
Natalia Melnikov ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Light Chain ◽  
Lymphocytic Leukemia ◽  
Light Chains ◽  
P Value ◽  
Advanced Stage ◽  
Free Light Chains ◽  
Monoclonal Protein ◽  
Low Levels ◽  
Monoclonal Proteins

Abstract Monoclonal proteins(MPs) can frequently be detected in the serum/urine of chronic lymphocytic leukemia(CLL) patients. Serum free light chains(FLC) assays can detect MPs in the absence of M bands on immunofixation(IMF).An abnormal FLC ratio indicates excess of one light chain type suggesting clonality.We evaluated fresh serum/urine samples from 34 CLL patients at various stages of disease by quantitative nephelometric assay,IMF and FLC assay.Median age was 66 yrs(43–87),M:F 1.9:1 and median time from diagnosis 41.5 mos(5–288). 45% had advanced stage and 39% prior treatment with 1–7 therapies.Only 2 patients had mild renal failure.Serum immunoglobulins were normal/low in 94% of patients:IgG (171–1580 mg/l, median 803 mg/l), IgA(<25–310 mg/l, median 88 mg/l),IgM(<18–290 mg/l, median 38 mg/l), irrespective of the presence of a monoclonal protein. 71% of patients had evidence of abnormal immunoglobulin synthesis: by IMF alone (8),IMF and FLC(10) or FLC alone(8).Abnormal FLC ratios were more frequently associated with advanced stage disease and increased κ chains(see table 1). Abnormal FLC ratios(< 0.26 or >1.65) were measured in 18(53%) patients, 8 of whom did not have MPs by IMF. Two advanced stage patients had abnormal FLC ratios due to very low levels of a single light chain, most probably reflecting secondary hypogammaglobulinemia due to CLL and/or chemotherapy.Abnormal FLC ratios reverted to normal after 1 course of chemotherapy(FC+/−R) in 3 patients despite persistence of minimal residual disease(MRD).FLC were of the same type as expressed on the surface of CLL cells, with discrepancies observed in 5 patients.BM biopsy staining for light chains revealed IgAκ MGUS in addition to λ chain restricted CLL in one patient, but was noncontributory in the other 4. Conclusions: Neither IMF nor the FLC assay alone could detect all MPs. Normal FLC ratios do not exclude the presence of MPs. The FLC ratio should be interpreted with caution in CLL patients with advanced disease and hypogammaglobulinemia. Monoclonal bands and abnormal FLC ratios can be detected despite normal or low levels of serum immunoglobulins in CLL patients. The significance of these monoclonal gammopathies in CLL is not clear and warrants further study in a larger group of patients. Discrepancies between surface immunoglobulins and serum/urine MPs might suggest the presence of an additional condition:ex. MGUS. FLC may not be a sensitive measure of MRD. Normal FLC ratio Abnormal FLC ratio P value *median No. patients 16(47%) 18(53%) M:F 1.3:1 3.5:1 NS Age* 62.5 yrs(49–73) 68 yrs(43–87) NS Time from CLL diagnosis* 25.3 mos(0–282) 59 mos(0–210) NS Adv stage(Rai III/IV-Binet C) 25% 66.7% 0.018 Untreated 62% 50% NS CLL:κ:λ restriction 7:8(0.88:1) 11:6(1.8:1) NS Monoclonal protein 8(50%) 10(56%) NS Increased freeκ no. 8 15 0.043 Freeκ level* 19.6(4.5–200) 39.2(2.9–386) 0.0064 Increased freeλ no 4 3 NS Free λ level* 19.3(12.4–146) 15.4(0.1–517) NS Serum β 2m* 3.1(1.8–6.7) 4.3(2.2–10.2) NS Zap70≥20 86% 36% 0.002 CD38≥30 44% 44% NS 17pdel/11qdel 40% 44% NS

Effect of Different Integration Approaches to the M-Spike Quantification in Serum Protein Electrophoresis and How It Correlates to the New Heavy/Light Chain Assay

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 5345-5345
Author(s):  
Juana Jiménez Jiménez ◽  
Tiago Pais ◽  
Luisa Campos ◽  
Carmen Hernando de Larramendi
Keyword(s):  
Binding Site ◽  
Serum Protein ◽  
Light Chain ◽  
Relative Difference ◽  
Protein Electrophoresis ◽  
Integration Methods ◽  
Monoclonal Protein ◽  
M Spike ◽  
Total Immunoglobulin ◽  
Better Than

Abstract Introduction To measure the Monoclonal Protein (MP) is essential in monoclonal gammopathies (MG) for both diagnosis and response assessment. However, the M-spike quantification may be affected by the inherent subjectivity and by the opted integration method to determine the area under the M-spike corresponding to the MP in a serum protein electrophoresis (SPE). Co-migration with other serum proteins and strong polyclonal background may also affect the MP accurate measurement. Due to its pivotal role in managing MG, and since new automatized techniques have been developed for the MP quantification, this study aims at compare different M-spike integration methods on the measurement of MP, and compare it to the new Heavy/Light chain assay (HLC/ Hevylite®), which allows to separately quantify, by automated nephelo/turbidimetry, the serum levels of IgG-K, IgG-L, IgA-K, IgA-L, IgM-K and IgM-L. Material and Methods 147 samples from 143 MGUS and MM patients were included. All the samples were analyzed by SPE (SEBIA- HYDRASYS 2) and two integration methods were used for quantifying the MP: MP1: peak defined until baseline; MP2: peak defined excluding the polyclonal part. The size of the paraprotein measured by the MP1 method was used to divide the samples in MP<10g/L and MP>10g/L. Statistical analysis included Passing-Bablok (PB) and Bland-Altman (Analyse-It®) and Mann-Whitney test (GraphPad Prism). Results The MP quantification by the MP1 and MP2 methods was significantly different (medians: 7.4 g/L vs 4.1 g/L, P<0.0001), with a relative difference of -64.36%. When dividing samples according to the MP size, the mean relative difference found was higher in samples with MP<10g/L than MP>10g/L (MP1:-85.02% vs MP2:-28.23%; medians: 5.4g/L vs 2.2g/L, P<0.0001; and 18.45g/L vs 14.65g/L, P=0.0253; respectively). Likewise, the correlation between MP1 and MP2 was good (r=0.991) but it weakened to r=0.864 in samples with MP< 10g/L. Therefore, the two integration methods diverged more in the quantification of small MP. In all analysis, MP1 correlated better than the MP2 method with the involved HLC (iHLC) (r=0.886 and r=0.87, respectively) and the total Ig (r=0.924 and r=0.9, respectively), with lower mean relative differences. The MP1 correlation with iHLC was considerably better in samples with MP>10g/L in respect to MP<10g/L (r=0.837 and r=0.55, respectively). PB analysis further revealed an agreement between MP1 and iHLC quantification in samples with MP>10g/L: iHLC=2.096+1.045PM1 (95%CI: Intercept -3.978 to 5.719; Slope: 0.8568 to 1.320), confirming that Hevylite is a useful tool for the MP quantification. Moreover, PB analysis on the summation of Heavy/Light pairs of the same immunoglobulin isotype resulted in an agreement with the levels of total Immunoglobulin (tIg) (r=0.857. PB: ∑HLC=0.1819+0.9211tIg; 95%CI: Intercept -0.9733 to 1.331; Slope: 0.8454 to 1.006), being slightly better in MP<10g/L than >10g/L, indicating the HLC analysis is valid for small MP measurements. HLC analysis also allows measuring the uninvolved-HLC pair (uHLC), a new immunoparesis parameter than has been suggested to have prognostic value. In this study, 32/34 MM and 49/109 MGUS samples had suppressed levels of uHLC. Interestingly, the MP1 and MP2 correlation with iHLC was better in MM than in GMSI samples (r=0,864 and r=0,857, versus, r=0,678 and r=0,606, respectively), which may be due both to generally higher levels of MP or lower polyclonal background in MM samples. Furthermore, 2/109 MGUS samples resulted in a different risk-of-progression category depending on the method of M-spike integration, with the iHLC being in agreement with the MP1 in one of the samples and discordant with the other. Conclusions The MP measurement by M-spike integration until baseline correlated with the iHLC and total immunoglobulin measurement better than when the M-spike integration excludes the polyclonal part. The good agreement between the iHLC and SPE in the quantification of the monoclonal protein puts this assay as an alternative method especially relevant at low concentration levels, which may help correcting for methodology associated variability within clinical laboratories. Finally, HLC may be easier to standardize than the SPE analysis and could eliminate the need for total Ig quantification. Disclosures Pais: The Binding Site Spain: Employment. Campos:The Binding Site Spain: Employment.

scholarly journals Immunoglobulin D amyloidosis: a distinct entity

Blood ◽  
2012 ◽  
Vol 119 (1) ◽  
pp. 44-48 ◽  
Author(s):  
Morie A. Gertz ◽  
Francis K. Buadi ◽  
Suzanne R. Hayman ◽  
David Dingli ◽  
Angela Dispenzieri ◽  
...  
Keyword(s):  
Light Chain ◽  
Monoclonal Gammopathy ◽  
Cardiac Involvement ◽  
Distinct Entity ◽  
Monoclonal Protein ◽  
Light Chain Amyloidosis ◽  
Clinical Syndromes ◽  
Immunoglobulin D ◽  
History Of ◽  
Monoclonal Proteins

Abstract IgD monoclonal gammopathies are uncommon. They are seen rarely as a monoclonal gammopathy of undetermined significance and are present in 1%-2% of patients with multiple myeloma. In light-chain amyloidosis, IgD monoclonal proteins are found in ap-proximately 1% of patients. When an IgD monoclonal protein is found, amyloidosis is often omitted from the differential diagnosis. In the present study, we reviewed the natural history of IgD-associated amyloidosis among 53 patients seen over 41 years. The distribution of clinical syndromes suggests that these patients have a lower frequency of renal and cardiac involvement. The overall survival of these patients does not appear to be different from that of patients who have light-chain amyloidosis associated with another monoclonal protein.

Laboratory testing requirements for diagnosis and follow-up of multiple myeloma and related plasma cell dyscrasias

2016 ◽  
Vol 54 (6) ◽  
Author(s):  
Maria A.V. Willrich ◽  
Jerry A. Katzmann
Keyword(s):  
Multiple Myeloma ◽  
Serum Protein ◽  
Plasma Cell ◽  
Light Chain ◽  
Cell Clone ◽  
Protein Electrophoresis ◽  
Free Light Chain ◽  
Molecular Weights ◽  
Immunofixation Electrophoresis ◽  
Monoclonal Proteins

AbstractMonoclonal immunoglobulins are markers of plasma cell proliferative diseases and have been described as the first (and perhaps best) serological tumor marker. The unique structure of each monoclonal protein makes them highly specific for each plasma cell clone. The difficulties of using monoclonal proteins for diagnosing and monitoring multiple myeloma, however, stem from the diverse disease presentations and broad range of serum protein concentrations and molecular weights. Because of these challenges, no single test can confidently diagnose or monitor all patients. Panels of tests have been recommended for sensitivity and efficiency. In this review we discuss the various disease presentations and the use of various tests such as protein electrophoresis and immunofixation electrophoresis as well as immunoglobulin quantitation, free light chain quantitation, and heavy-light chain quantitation by immuno-nephelometry. The choice of tests for inclusion in diagnostic and monitoring panels may need to be tailored to each patient, and examples are provided. The panel currently recommended for diagnostic screening is serum protein electrophoresis, immunofixation electrophoresis, and free light chain quantitation.

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