Application of an optimized interpretation model in capillary hemoglobin electrophoresis for newborn thalassemia screening.

INTRODUCTION: Newborn screening is an important supplement to thalassemia control and prevention. Capillary electrophoresis (CE) technology has several advantages for thalassemia screening but with low sensitivity, especially for thalassemia carriers. This study aims to illustrate the application of an optimized interpretation model in newborn thalassemia screening by capillary hemoglobin electrophoresis. METHODS: Two thousand, two hundred fifty-eight neonates selected from four regions in China were enrolled and were screened for α-thalassemia and ß-thalassemia by capillary electrophoresis. Results were interpreted based on an optimized model integrated with multiple parameters. Molecular analysis was carried out in synchrony and used as the gold standard for the screening performance assessment. The consistency among different regions and thalassemia genotypes were also investigated. RESULTS: Among the 2258 neonates, 485 were identified to have a likely diagnosis of thalassemia, and 422 α-thalassemia, 80 ß-thalassemia, and 21 α/ß-thalassemia cases were confirmed by molecular analysis, including 277 α-thalassemia silent carriers, 135 α-thalassemia trait carriers, 10 Hemoglobin H disease, and 80 ß-thalassemia trait carriers. The screening sensitivity, specificity, positive, and negative predictive value for α-thalassemia and ß-thalassemia were 84.83%, 99.14%, 95.98%, 96.41%, and 88.75%, 98.73%, 76.34%, and 99.48%, respectively. The optimized interpretation model showed higher performance for thalassemia carriers, though some neonates with silent α-thalassemia genotypes (-α3.7 /αα, -α4.2 /αα, and αWS α/αα) and ß-28 /ßN genotype were still missed. The screening performance among different regions was comparable. CONCLUSIONS: Capillary hemoglobin electrophoresis with the optimized interpretation model shows reliable performance for newborn thalassemia screening. It is applicable to large-scale population screening.

Analytical sensitivity and diagnostic performance of serum protein electrophoresis on the HYDRAGEL 30 PROTEIN(E) ß1-ß2 Sebia Hydrasys system.

BACKGROUND: Serum protein electrophoresis (SPE) and immunofixation electrophoresis (IFE) are used in the diagnosis and monitoring of plasma cell dyscrasias. IFE is considered the most sensitive method for the detection of monoclonal proteins (M-proteins), but it is not quantitative. The goal of this study was to establish the analytical sensitivity and diagnostic performance of SPE on the Sebia Hydrasys using HYDRAGEL 30 PROTEIN(E) ß1-ß2. METHODOLOGY: Patient sera with a previously identified M-protein (IgG, IgA or IgM) were serially diluted with a normal serum pool and electrophoresed on the Sebia Hydrasys using HYDRAGEL 30 PROTEIN(E) ß1-ß2. The SPE gels were individually interpreted by five independent observers and IFE was performed on selected samples. Limit of detection was determined as the lowest concentration of M-protein band visible on the gel. SPE diagnostic performance was evaluated against the "gold standard" IFE according CLSI EP12-A2 guidelines. RESULTS: Detection limit was comparable among all M-proteins migrating in the gamma region, IgG-κ (0.18±0.08g/L; n=6), IgG-λ (0.36±0.25g/L; n=8), IgA-κ (0.40±0.13g/L; n=7), IgA-λ (0.37±0.23g/L; n=4), IgM-κ (0.47±0.20g/L; n=13) and IgM-λ (0.29±0.24g/L; n=6). Percentage agreement with IFE for IgG and IgA in the gamma region ranged from 65% to 100%, whereas IgM migrating in the gamma region and immunoglobulins co-migrating with alpha or beta globulins, showed poor (0-38%) agreement. CONCLUSIONS: This study evaluates the analytical sensitivity and diagnostic performance of SPE on the Sebia Hydrasys using HYDRAGEL 30 PROTEIN(E) ß1-ß2. There was acceptable agreement between SPE and IFE for IgG-κ/λ and IgA-κ/λ migrating in the gamma region, suggesting that repeating IFE for samples with these isotypes, when the previous IFE and second SPE are both negative, may not be necessary.

Crioglobulinas: características y metodología de estudio. Recomendación (2014) / Cryoglobulins: features and methodology of study. Recommendation (2014)

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Moving towards harmonized reporting of serum and urine protein electrophoresis.

During the last decade, surveys by questionnaire in Canada, Australia and New Zealand revealed wide variation in reporting practices by laboratories and individual practitioners in the interpretation of serum and urine protein electrophoresis (PE). Such variation has potential to adversely impact patient outcomes if report structure is inconsistent or if the messaging is incorrectly perceived by the receiving physician. Concerted efforts have been initiated to promote harmonization in the use of interpretative comments. The primary goal is to add value through clear communication with requesting physicians in the interest of quality patient care. Resistance to a harmonized approach largely reflects longstanding personal reporting habits and preferences but change can be more readily embraced if the new system is intuitive, easy to use and saves time in reporting.

Value of reflex testing based on hypogammaglobulinemia as demonstrated in serum protein electrophoresis.

OBJECTIVES: Hypo-gammaglobulinemia (hypoGG) in serum protein electrophoresis (SPE) reflects, variably, reduced serum immunoglobulin (Ig) concentrations, which may be caused by hematological neoplasms, among other causes. HypoGG in the absence of a discernible M-spike (MC) has been the basis of reflexive testing e.g., by immunofixation electrophoresis (IFE). However, the utility of this practice has not been fully evaluated. Thus, we aimed to (1) determine the predictive power of hypoGG for reduced Ig levels, (2) compare the IFE positive rates and sensitivity between hypoGG and non-hypoGG patients, and (3) examine the M-protein isotype distributions. METHODS: We retrospectively analyzed 3974 matched SPE and IFE results at the Sunnybrook Health Sciences Centre from January 2010 to June 2013. SPE and IFE were performed on the Sebia Capillarys™ 2 and Hydrasys™ systems respectively. RESULTS: 2723/3974 (68.5%) patients were SPE negative, 246/2723 (9%) had hypoGG and 192 (7.1%) were IFE positive. HypoGG predicted 93.1% cases with at least one Ig reduction. Among SPE-negative patients, the IFE positive rate and sensitivity in hypoGG were 12.2% and 15.6% respectively, compared to 6.4% and 77.1% in normo-GG. Proportion of non-IgG isotypes in both groups were comparable but fewer MC were detected in hypoGG. CONCLUSIONS: Both the 7% false negative rate of SPE and the poor sensitivity (16%) of reflex testing based on hypoGG should be taken into consideration when devising a screening strategy based on SPE.

γ/IgG ratio: role in distinguishing monoclonal spikes from fibrinogen.

Serum protein electrophoresis (SPEP) is a standard screening method for detecting monoclonal gammopathies. Presence of fibrinogen, however, can mimic a true monoclonal spike and interfere with accurate monoclonal protein identification. We describe a novel approach for distinguishing fibrinogen spikes from true monoclonal spikes. We classified 600 individual patient samples into four groups: group 1, 58 samples with a fibrinogen spike; group 2, 127 samples with a spike due to a monoclonal gammopathy; group 3, 181 samples with previously established monoclonal gammopathies but resolved posttreatment; and group 4, 234 control samples without monoclonal gammopathies. The value of using a γ region fraction/IgG ratio in distinguishing fibrinogen from true monoclonal spikes was assessed. The γ/IgG ratio in the fibrinogen group is significantly (P<0.0001) higher than this ratio in the other three groups. A γ/IgG ratio cut-off value of 1.13 discriminates true monoclonal gammopathies from fibrinogen. Moreover, exclusion of elevated IgA or IgM cases improves the ratio's predictive power. The probability cut-off is 0.756, corresponding to a γ/IgG ratio of 1 (93% sensitivity, 91% specificity). Using the γ/IgG ratio improves the screening power of SPEP and offers a simple and reliable diagnostic tool for distinguishing fibrinogen spikes from true monoclonal spikes.

Reference values for serum proteins of common laboratory rodent strains.

Protein electrophoresis is a common proven technique to determine the protein components of plasma or serum in human, veterinary, and laboratory animal medicine. Changes in albumin and globulin protein levels can provide early and valuable diagnostic and prognostic information. Here we describe a preliminary analysis of the distribution of serum protein fractions in adult BALB/c, C57BL/6, and CD1 mice and Sprague-Dawley rats and describe the changes in protein values from birth to maturity in BALB/c mice and Sprague-Dawley rats. Quantifiable changes in the electrophoretic profile were apparent in mice with chronic-active dermatitis.

Effect of hemolysis on plasma protein levels and plasma electrophoresis in birds.

Protein electrophoresis is recognized as a reliable diagnostic tool for birds even though results are seldom pathognomonic. Unfortunately, this technique is underused in avian medicine because many factors interfere with electrophoresis patterns; hemolysis is one of these factors and is often associated with improper specimen handling. In human laboratory medicine, hemolysis is a known interference factor that can lead to erroneous results. Published data on the influence of hemolysis on protein electrophoresis in birds is currently restricted to a single study in Psittacidae. The aim of this study was to further investigate this effect and to analyze potential interspecific differences. Blood samples were drawn from 28 Black Kites (Milvus migrans) and 19 Bar-headed Geese (Anser indicus) and separated into two aliquots. One aliquot was dipped into liquid nitrogen for 5 sec in order to cause freeze-thawing hemolysis before centrifugation. Total plasma protein concentration, plasma hemoglobin concentration, and plasma protein electrophoresis patterns were determined for both hemolyzed and nonhemolyzed samples. In both species, hemolysis resulted in falsely elevated total plasma protein concentration. In Bar-headed Geese, hemolysis caused a rise in the gamma fraction. In Black Kites, this rise involved not only the gamma fraction but also the beta fraction, stressing the potential for species-related differences. In both species, the effects of hemolysis mimicked a chronic inflammatory condition with resulting antigenic stimulation.

Serum free light chains; the need to establish local reference intervals.

BACKGROUND: The purpose of this study was to compare The Binding Site serum free light chain assay on two analytical platforms; the Dade Behring BNII and the Olympus AU400. Reference intervals were subsequently established on each analyser. METHODS: In total, 112 serum samples routinely submitted to the laboratory for protein electrophoresis were used for the comparison study. Reference interval data was generated from 126 ostensibly healthy anonymous individuals. RESULTS: Serum free light chain results on the BNII and AU400 analysers are not directly comparable. The BNII produces results which are significantly higher than the AU400. CONCLUSIONS: Laboratories using The Binding Site serum free light chain assay are strongly advised to establish local reference intervals.

Plasma electrophoretogram in feline immunodeficiency virus (FIV) and/or feline leukaemia virus (FeLV) infections.

The electrophoretogram of 89 cats, including those infected by feline immunodeficiency virus (FIV+), feline leukaemia virus (FeLV+) and non-infected, showed statistically significant differences in several of the fractions. FIV+ cats had very high protein values (mean, 8.10 g/dl), mostly because of hypergammaglobulinemia (mean, 2.81 g/dl) as compared with non-infected animals and FeLV+. In addition, in these FIV+ animals, the albumin/globulins ratio (A/G) was very low (mean, 0.72). Statistically significant differences in A/G and alpha2-globulin fraction were observed in FeLV+ group (A/G mean, 0.88 +/- 0.08; alpha2-globulin, mean, 0.84 +/- 0.07 g/dl) when compared with non-infected group (A/G mean, 1.06 +/- 0.08; alpha2-globulin mean, 0.68 +/- 0.04 g/dl). The alpha1-globulin fraction was higher in double infected animals (FIV and FeLV positive, F-F) (3.55 g/dl), than in FeLV+ or FIV+ cats (3.10 and 3.07 g/dl respectively), but no statistical conclusions may be drawn from this fact because of the low number of F-F animals. This technique may help to assess the initial clinical status of retrovirus-infected cats, and the clinical course of these chronic diseases, specifically during and after suitable therapy.

Understanding and interpreting serum protein electrophoresis.

Serum protein electrophoresis is used to identify patients with multiple myeloma and other serum protein disorders. Electrophoresis separates proteins based on their physical properties, and the subsets of these proteins are used in interpreting the results. Plasma protein levels display reasonably predictable changes in response to acute inflammation, malignancy, trauma, necrosis, infarction, burns, and chemical injury. A homogeneous spike-like peak in a focal region of the gamma-globulin zone indicates a monoclonal gammopathy. Monoclonal gammopathies are associated with a clonal process that is malignant or potentially malignant, including multiple myeloma, Waldenstrom's macroglobulinemia, solitary plasmacytoma, smoldering multiple myeloma, monoclonal gammopathy of undetermined significance, plasma cell leukemia, heavy chain disease, and amyloidosis. The quantity of M protein, the results of bone marrow biopsy, and other characteristics can help differentiate multiple myeloma from the other causes of monoclonal gammopathy. In contrast, polyclonal gammopathies may be caused by any reactive or inflammatory process.

Quality control and quality assurance aspects of the routine use of capillary electrophoresis for serum and urine proteins in clinical laboratories.

Using capillary electrophoresis (CE) for serum protein electrophoresis, the quality of results begins with monitoring a well-functioning instrument, using scrupulously clean capillaries, well-calibrated methods as well as regular use of an internal quality control material. Quality assurance programs are available in countries such as Australia, United Kingdom, United States, and European countries such as Sweden and Germany. The present commercial control material that is available gives percentages of albumin, alpha 1, alpha 2, beta- and gamma-globulins, the gamma-component being of normal distribution, and not containing any monoclonal protein component. We feel that a quantitative commercial control material containing a monoclonal protein at decision level for treating myeloma patients would be beneficial to all laboratories as a serum protein electrophoresis control, whether the analysis is by CE or agarose gels. The same applies for control material for urinary protein electrophoresis.

[Serum protein immunofixation in malignant hemopathies other than multiple myeloma and Waldenstrom's macroglobulinemia]. / Immunofixation des protéines sériques dans les hémopathies malignes autres que le myélome multiple et la maladie de Waldenström.

The interest of serum protein immunofixation in myeloma and Waldenstr m's macroglobulinemia is widely known. It is not so well defined in other malignant hemopathies. The purpose of this study was to determine immunofixation abnormalities in malignant hemopathies other than multiple myeloma and Waldenstr m's macroglobulinemia. We selected serum immunofixations of 61 patients affected by malignant hemopathies and 53 patients affected by other pathologies susceptible to give immunofixation's alterations. We showed that the frequency of immunofixation abnormalities was more important in patients affected by malignant hemopathies than in patients affected by other pathologies (70.5% vs 35.8%). A high frequency of monoclonal immunoglobulins was found in patients with lymphoma (53.3%) and oligoclonal immunoglobulins in other hemopathies (48.2%). No significant difference of the frequency of the monoclonal immunoglobulin isotypes was found. In summary, this retrospective study demonstrates a high frequency of immunofixation abnormalities in malignant hemopathies other than multiple myeloma and Waldenstr m's macroglobulinemia and different immunofixation characteristics between lymphomas and other hemopathies.