PROTEIN ELECTROPHORESIS AND REFERENCE INTERVALS OF SERUM PROTEINS OF A CAPTIVE POPULATION OF ROTI ISLAND SNAKE-NECKED TURTLES (CHELODINA MCCORDI).

Protein electrophoresis (PEP) is an important tool in mammals to characterize specific dysproteinemias and detect acute and chronic inflammatory responses. In reptiles, PEP is the gold standard method for globulin fraction determination and albumin measurement. In this study, preliminary reference intervals were established for serum PEP in 22 clinically healthy adult Roti Island snake-necked turtles (Chelodina mccordi), a critically endangered species, kept in captivity and sampled over two monsoon seasons. The species has a prominent prealbumin fraction and ß-globulins were the dominant globulin fraction. Significant differences between females and males were found in prealbumin (P < 0.01), albumin (P = 0.02), α1-globulin (P = 0.05) and γ-globulin (P = 0.01). Gravid females had significantly lower total protein (P < 0.01), prealbumin (P < 0.01), albumin (P < 0.01) and albumin:globulin ratio (P = 0.01). These preliminary reference intervals should aid in clinical investigation in this species as well as further research studies seeking to understand the application of PEP in reptilian species.

Serum Protein Electrophoresis Patterns in Patients with Osteoarticular Tuberculosis.

CONTEXT AND AIMS: Tuberculosis (TB) is a leading cause of infectious disease deaths in India. It is also one of the most challenging diseases to diagnose and treat effectively. TB can occur both in the lungs and in extrapulmonary locations through hematogenous spread. Osteoarticular TB is a type of extrapulmonary characterized by atypical presentation. If diagnosed early, it can be treated effectively with reduced risk of mortality. SUBJECTS AND METHODS: At Nalanda medical college and hospital, an 18-month prospective research was undertaken. The study included a total of 120 patients with osteoarticular TB. Serum electrophoresis of blood samples was performed at baseline, 2 months, and 4 months following antitubercular medication administration. The fractions of albumin, α1, α2, ß, and γ globulins were estimated and compared with the baseline value. RESULTS: It was observed that as the disease progressed and became more chronic, there was a decrease in albumin and an increase in α1, α2, ß, and γ globulin percentages of serum proteins. Upon follow-up, the serum electrophoresis revealed that these values observed during baseline could be reversed by the administration of antitubercular drugs. CONCLUSIONS: This study suggests that analyzing serum protein fractions could be a cost-effective strategy to determine the presence of osteoarticular TB and also aid in initiating antitubercular treatment.

RésuméContexte et objectifs: La tuberculose (TB) est l'une des principales causes de décès par maladies infectieuses en Inde. C'est également l'une des maladies les plus difficiles à diagnostiquer et à traiter efficacement. La tuberculose peut survenir à la fois dans les poumons et dans des localisations extrapulmonaires par propagation hématogène. La tuberculose ostéoarticulaire est un type de tuberculose extrapulmonaire caractérisée par une présentation atypique. Si elle est diagnostiquée tôt, elle peut être traitée efficacement avec un risque de mortalité réduit. Sujets et méthodes: À la faculté de médecine et à l'hôpital de Nalanda, une recherche prospective de 18 mois a été entreprise. L'étude a inclus un total de 120 patients atteints de tuberculose ostéoarticulaire. L'électrophorèse sérique des échantillons de sang a été réalisée au départ, 2 mois et 4 mois après l'administration de médicaments antituberculeux. Les fractions d'albumine, a1, a2, b et g globulines ont été estimées et comparées à la valeur de base. Résultats: Il a été observé qu'à mesure que la maladie progressait et devenait plus chronique, il y avait une diminution de l'albumine et une augmentation des pourcentages de globulines a1, a2, b et g des protéines sériques. Lors du suivi, l'électrophorèse sérique a révélé que ces valeurs observées au départ pouvaient être inversées par l'administration de médicaments antituberculeux. Conclusions : Cette étude suggère que l'analyse des fractions protéiques sériques pourrait constituer une stratégie rentable pour déterminer la présence d'une tuberculose ostéoarticulaire et également faciliter l'initiation d'un traitement antituberculeux.

Expert-level detection of M-proteins in serum protein electrophoresis using machine learning.

OBJECTIVES: Serum protein electrophoresis (SPE) in combination with immunotyping (IMT) is the diagnostic standard for detecting monoclonal proteins (M-proteins). However, interpretation of SPE and IMT is weakly standardized, time consuming and investigator dependent. Here, we present five machine learning (ML) approaches for automated detection of M-proteins on SPE on an unprecedented large and well-curated data set and compare the performance with that of laboratory experts. METHODS: SPE and IMT were performed in serum samples from 69,722 individuals from Norway. IMT results were used to label the samples as M-protein present (positive, n=4,273) or absent (negative n=65,449). Four feature-based ML algorithms and one convolutional neural network (CNN) were trained on 68,722 randomly selected SPE patterns to detect M-proteins. Algorithm performance was compared to that of an expert group of clinical pathologists and laboratory technicians (n=10) on a test set of 1,000 samples. RESULTS: The random forest classifier showed the best performance (F1-Score 93.2 %, accuracy 99.1 %, sensitivity 89.9 %, specificity 99.8 %, positive predictive value 96.9 %, negative predictive value 99.3 %) and outperformed the experts (F1-Score 61.2 ± 16.0 %, accuracy 89.2 ± 10.2 %, sensitivity 94.3 ± 2.8 %, specificity 88.9 ± 10.9 %, positive predictive value 47.3 ± 16.2 %, negative predictive value 99.5 ± 0.2 %) on the test set. Interestingly the performance of the RFC saturated, the CNN performance increased steadily within our training set (n=68,722). CONCLUSIONS: Feature-based ML systems are capable of automated detection of M-proteins on SPE beyond expert-level and show potential for use in the clinical laboratory.

PLASMA PROTEIN ELECTROPHORESIS IN THE WHITE STORK (CICONIA CICONIA): AGREEMENT BETWEEN AGAROSE GEL VERSUS CAPILLARY ZONE METHODS AND DEVELOPMENT OF REFERENCE INTERVALS.

The white stork (Ciconia ciconia) is a ciconiiform species widely represented in zoological institutions. Plasma protein electrophoresis is widely used in avian patients for assessment of inflammatory conditions, but reference intervals for this testing modality are lacking for the white stork. The two main electrophoretic methods are agarose gel electrophoresis (AGE) and capillary zone electrophoresis (CZE). This study assessed fresh plasma samples of healthy adult white storks (n = 30). Statistical analyses were performed to evaluate agreement between AGE and CZE. Typical electrophoretic fractions were obtained from both methods (prealbumin, albumin, α1, α2, ß, γ1, and γ2). The AGE and CZE methods were not equivalent for determining major electrophoretic fractions (except ß-globulins) and albumin:globulin ratio on plasma samples. An additional prealbumin fraction was seen with CZE. Reference intervals were established for each method as the smallest n group was 27 individuals for a given value; most values had normal distribution, and robust or parametric methods were used on the data.

Significance of serum protein electrophoresis in the diagnosis of Tsukayama type IV periprosthetic joint infection.

Objectives: To investigate the efficacy of serum protein electrophoresis (SPE) in the diagnosis of periprosthetic joint infection (PJI) after hip and knee arthroplasty. Methods: The medical records of patients undergoing hip and knee arthroplasty at a class A tertiary hospital between August 2013 and January 2021 were retrospectively investigated. A total of 179 patients were included and divided into two groups: 66 patients in the PJI group and 113 patients in the aseptic loosening (AL) group. Serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), D-dimer, Fibrinogen, Serum albumin and the proportion of serum protein in SPE were compared between the two groups. The diagnostic sensitivity and specificity were determined using the receiver operating characteristic (ROC) curve, and the diagnostic value was compared using the area under the ROC curve (AUC). Results: There was no significant difference in age, sex and body mass index (BMI) between PJI group and AL group (P>0.05), but there was significant difference in the ratio of hip to knee (X2 = 22.043, P<0.001). The CRP, ESR, D-dimer, Fibrinogen and the proportion of α1 globulin band in PJI group was 22.99(10.55,40.58) mg/L, 37.00(23.00,61.70) mm/h, 790.00(500.00,1500.00) ng/ml, 4.84(3.81,5.55) g/L and 5.80(5.00,7.73) % which was higher than that in AL group [1.89(0.50,4.12) mg/L, U=7.984, P<0.001; 10.10(7.00,16.90) mm/h, U=8.095, P<0.001; 570.00(372.50,780.00) ng/ml, U=3.448, P<0.001; 2.84(2.45,3.43) g/L, U=8.053, P<0.001 and 4.20(3.90,4.80) %, U=8.154, P<0.001]. The Serum albumin and the proportion of Albumin band in PJI group was 36.10(33.10,39.00) g/L and 49.00(44.95,52.20) % which was lower than that in AL group [38.10(34.00,41.10) g/L, U=-2.383, P=0.017 and 54.40(51.55,56.70) %, U=-6.162, P<0.001]. The proportion of In PJI group, the AUC of proportion of α1 globulin was 0.8654, which was equivalent to CRP (0.8698), ESR (0.8680) and outperformed that of fibrinogen (0.8025). Conclusions: Elevated proportion of α1 globulin in SPE presented with good diagnostic value for Tsukayama type IV PJI, and its accuracy was comparable to those of ESR and CRP. And α1 globulin can assist with CRP and ESR to determining the timing of second-stage revision.

Association of serum protein electrophoresis with clinicopathological characteristics and its prognostic relevance in chronic lymphocytic leukaemia patients.

Objective: To assess the association of serum protein electrophoresis abnormalities with clinicopathological characteristics, and its impact on overall survival in chronic lymphocytic leukaemia patients. METHODS: The prospective study was conducted at Haematology and Immunology departments of the University of Health Sciences, Lahore, Pakistan, from 2019 to 2022, and comprised newly diagnosed chronic lymphocytic leukaemia patients. Lactate dehydrogenase and beta-2 microglobulin levels were measured by spectrophotometric principle, whereas serum protein electrophoresis was determined through commercially available capillary electrophoresis systems. Patients were followed up for 2 years post-diagnosis. Data was analysed using SPSS 21. RESULTS: Of the 50 patients, 40(80%) were males and 10(20%) were females. The overall mean age was 60±11 years. Serum protein electrophoresis was available for 40(80%) patients, and, among them, 12(30%) patients had abnormal levels, while 29(72.5%) required treatment. Overall response rate was 25(86.2%), and median two-year overall survival was 16.5 months (95% confidence interval: 10-20 months). Abnormal serum protein electrophoresis was significantly associated with Binet stage C, lower mean haemoglobin levels and higher median levels of lactate dehydrogenase and beta-2 microglobulin (p<0.05)). Regarding overall survival, the survival curves of chronic lymphocytic leukaemia patients with normal and abnormal serum protein electrophoresis status differed significantly (p=0.04). Conclusion: Abnormal serum protein electrophoresis could be considered a surrogate marker for advanced chronic lymphocytic leukaemia disease.

An up-conversion fluorescence lateral-flow immunoassay for rapid detection of Daratumumab in serum protein electrophoresis clinical samples.

BACKGROUND: Daratumumab (DARA) is a commonly used monoclonal antibody (mAb) drug for the treatment of multiple myeloma (MM). Its appearance as a visible abnormal band in the γ-region of a serum protein electrophoresis (SPEP) gel may interfere with the SPEP result interpretation. With the advantages of portability and rapid testing capabilities, up-conversion fluorescence lateral-flow immunoassay (LFA) can be an ideal solution to detect DARA interference. METHODS: An up-conversion fluorescence LFA strip was designed and constructed to perform semi-quantitative DARA testing in clinical samples. The LFA strip test was evaluated for limit of detection (LOD), dynamic range, and analytical interference. RESULTS: To demonstrate the clinical utility of the LFA strip, 43 SPEP-positive patient serum samples were tested for the presence of DARA, and the results exactly matched the DARA usage history in patient medical records. CONCLUSIONS: The performance of the up-conversion fluorescence LFA strip meets the purpose of clarifying DARA interference in SPEP results. It may be used as an independent and objective confirmation of the presence of DARA in clinical samples. The LFA strip offers a cost-effective rapid on-site test to check for DARA interference alongside standard SPEP equipment, which significantly improves the interpretation of ambiguous SPEP results involving DARA, and does not intervene the current SPEP workflow in clinical laboratory practice.

Discrepant serum creatinine concentrations caused by paraprotein interference preceding diagnosis of monoclonal gammopathy of undetermined significance.

We report a man in his 70s who presented with discrepant serum creatinine concentrations in different hospitals at the same time. Further examinations of these discrepancies revealed turbidity of the serum sample and, thus, a reagent reaction and false hypercreatinine caused by paraprotein interference were suspected. Serum protein electrophoresis revealed a small amount of monoclonal γ globulin (2.9 g/L), which may have been involved in paraprotein interference. Monoclonal λ-type IgG was detected in the serum, resulting in a diagnosis of monoclonal gammopathy of undetermined significance. Previous studies indicated paraprotein interference in serum containing monoclonal IgM or a large amount of IgG (> 25 g/L). Although this case of paraprotein interference induced by a small amount of IgG is rare, a discrepancy in creatinine results may be an indicator leading to the diagnosis of plasma cell proliferative diseases.

Characteristics of isatuximab-derived interference in serum protein electrophoresis and immunofixation, and an absence of sustained in vivo interference due to belantamab mafodotin and denosumab.

OBJECTIVES: Some therapeutic monoclonal antibodies, like daratumumab and elotuzumab, produce interfering monoclonal bands on serum protein electrophoresis (SPEP) and immunofixation electrophoresis (IFE). Whether other common therapeutic antibodies also produce interference has not been systematically evaluated. DESIGN AND METHODS: SPEP/IFE from patients receiving isatuximab (48 patients), belantamab mafodotin (BM; 41), and denosumab (41) were retrospectively reviewed for therapeutic antibody interference. Cases exhibiting isatuximab interference were quantified and the maximum duration of isatuximab effect was evaluated. To characterize band position, neat human serum was spiked with BM or denosumab at supratherapeutic concentrations. Band migration patterns were compared on SPEP and IFE, with band position expressed relative to other constant protein fractions. RESULTS: Isatuximab-induced IFE interference was common (81.3 % of evaluated patients) with a maximum observed duration of 8 weeks. 10.4 % of isatuximab patients had IgG kappa monoclonal gammopathies that co-migrated with the drug; this subset could benefit from HYDRASHIFT 2/4 isatuximab testing. 8.3 % of IFE cases were negative for an isatuximab band but showed large, endogenous M-spikes migrating elsewhere. All patients in this group expired within 1 year of this finding. We hypothesize that an inability to detect isatuximab in this setting corresponds to a large residual myeloma burden that reduces isatuximab serum concentration. This observation may serve as a negative prognostic factor. Spiking studies demonstrated that BM and denosumab produce interference in vitro, but sustained interference was not observed in >40 treated patients. CONCLUSIONS: Therapeutic antibody interference in patients receiving isatuximab is common, and can persist for at least 8 weeks after administration. >10 % of patients receiving isatuximab may benefit from HYDRASHIFT testing post-therapy. In contrast, BM and denosumab fail to produce sustained interference in treated patients.

SARS-CoV-2 infection is not associated with the emergence of monoclonal gammopathies.

BACKGROUND: Upon infection activated plasma cells produce large quantities of antibodies which can lead to the emergence of a monoclonal component (MC), detectable by serum protein electrophoresis (SPEP). This study aims to investigate any correlation between SARS-CoV-2 infection and MC development and, if identified, whether it persists during follow-up. METHODS: SPEPs of 786 patients admitted to hospitals between March 01 2020 and March 31 2022 were evaluated. Positive (SARS-CoV-2+) and negative (SARS-CoV-2-) patients to nasopharyngeal swab for SARS-CoV-2 by RT-PCR were included. The persistence/new occurrence of MC was investigated for all patients during follow-up. Patient groups were compared by chi-square analysis. RESULTS: MC was identified in 12% of all patients admitted to hospital, of which 28.7% were SARS-CoV-2+. The most common immunoglobulin isotype in both groups was IgG-k. There was no correlation between MC development and SARS-CoV-2 infection (p = 0.173). Furthermore, the risk of MC persistence in SARS-CoV-2-negative patients was revealed to be higher than in the SARS-CoV-2+ at follow-up (HR = 0.591, p = 0.05). CONCLUSIONS: Our study suggests that the detection of MC during SARS-CoV-2 infection is most likely due to the hyperstimulation of the humoral immune system, as also occurs in other viral infections.

Plasma cell myeloma with double M bands on Serum protein electrophoresis: A diagnostic conundrum?

ABSTRACT: Plasma cell myeloma (PCM) is a monoclonal gammopathy (MGM) characterized by proliferation of abnormal clone of plasma cells infiltrating the bone marrow with consequent end organ damage. The clonal plasma cells secrete a single clone of immunoglobulins (Ig) leading to presence of M-protein in the serum and/or urine. The M-protein is appreciated as a discrete band on serum protein electrophoresis (SPE) in the gamma globulin region, also called the M-band. Biclonal gammopathy (BGM) occurs due to neoplastic transformation of a plasma cell clone undergoing Ig class switching or due to an independent neoplastic transformation event yielding proliferation of unrelated plasma cell clones, therefore resulting in two distinct M-bands on SPE. It is, however, vital to distinguish a true BGM from an apparent one (MGM presenting with two distinct bands on SPE) so as to make an accurate diagnosis. Hereby, we report a case of a 61-year-old man, diagnosed with PCM and presenting with two discrete bands on SPE (simulating a BGM) which turned out to be monoclonal in nature.

Update on the outcome of M-protein screening program of multiple myeloma in China: A 7-year cohort study.

BACKGROUND: To improve the early detection rate of multiple myeloma (MM), the M-protein screening system has been performed in the hospital population at Zhongshan Hospital Fudan University since 2014, with electrophoretic-based monoclonal immunoglobulin (M-protein) screening integrated into the blood biochemistry panel. This study updated 7-year follow-up findings of MM patients diagnosed by screening-driven and symptom-driven approaches. METHODS: The retrospective study compared the characteristics and outcomes of patients diagnosed through two patterns by reviewing the plasma cell disease database from January 2014 to October 2021. The screening-driven group included patients diagnosed through the screening system during workups of unrelated medical conditions or routine checkups. In contrast, patients who visited or were referred to the hematological department due to myeloma-related end-organ damage were categorized into the symptom-driven group. RESULTS: There were 3,110,218 serum protein electrophoresis (SPEP) tests performed during 7 years, with 1.95% (60,609) patients yielding positive SPEP results. Of 911 confirmed MM cases (excluding concurrent amyloidosis), 366 were assigned to the screening-driven group, while 545 were to the symptom-driven group. Compared to the symptom-driven group, the screening group had more IgG subtypes, earlier International Stage System stages, fewer disease-related symptoms, lower ECOG scores, less extramedullary disease, a lower percentage of bone marrow plasma cells, and a lower level of lactate dehydrogenase. Frontline response results of two groups were similar. Patients detected through screening had a significantly improved median progression-free survival (PFS) than the symptom-driven group (62.2 vs. 24.9 months, p < 0.001, HR: 2.12, 95% CIs: 1.69-2.65), with median follow-ups of 32.6 and 27.4 months. Furthermore, the median overall survival (OS) was significantly longer in patients of the screening group (not reached vs. 62.3 months, p < 0.001, HR: 2.49, 95% CIs: 1.81-3.41). After being adjusted for well-acknowledged myeloma prognostic factors, the screening-driven diagnostic pattern remained an independent prognostic factor indicating improved PFS and OS in MM patients. CONCLUSION: Routine M-protein screening for MM in the hospital population results in an earlier diagnosis and better patient outcomes.

Early screening of thalassemia in pregnant women in northern China by capillary electrophoresis for the determination of hemoglobin electrophoresis.

The objective of this study was to analyze the effectiveness of capillary electrophoresis detection of hemoglobin electrophoresis (HE) for the early screening of thalassemia. In the first choice, 974 pregnant women were selected for capillary electrophoresis to detect HE, which showed that 46 of them were abnormal (4.72%), including 16 cases with HbA2<2.5% and 28 cases with HbA2>3.5% and/or HbF≥2.0%. In one case each of HbH and HbBart's abnormal bands was found. The genotype test results showed the presence of thalassemia in 34 cases, using the genotype test results as the gold standard, after calculation it was seen that capillary electrophoresis for HE diagnosis of the occurrence of thalassemia had a sensitivity and specificity of 54.34% and 70.97% (P<0.05). These results suggest that in the screening of thalassemia in northern China, capillary electrophoresis for HE has good application and can be used as one of the routine screening tools, but further confirmation by genotype testing is still needed.

Evusheld, a SARS-CoV-2 spike protein-directed attachment inhibitor, appears in serum protein electrophoresis and immunofixation: a case study.

Serum protein electrophoresis (SPE) and immunofixation (IFE) assays are commonly used to diagnose and monitor patients with multiple myeloma (MM). Identifying analytical interferences in SPE and IFE caused by therapeutic monoclonal antibodies (tmAbs) can be challenging. Here we report the case of a 72-year-old male with a long history of relapsed immunoglobulin (Ig)G kappa MM. A follow-up SPE showed the original peak plus 2 additional cathode peaks. Immunofixation was ordered as a reflex test to investigate the new peaks that showed initial patient monoclonal IgG kappa in addition to 2 restricted bands of the IgG kappa type. Therapeutic monoclonal antibody interference was suspected and the patient's chart was reviewed. The patient was not on any antimyeloma monoclonal antibody therapy. However, preexposure prophylaxis therapeutic monoclonal antibodies tixagevimab plus cilgavimab (Evusheld) for severe acute SARS-CoV-2 was administered approximately 45 minutes before sample collection, which led to the identifiable spikes and correlated bands. After 2 days, the IgG kappa bands disappeared, confirming this therapy's effect on SPE and IFE. Therefore, clinical pathologists should be aware of when providers prescribe new monoclonal antibody therapy and become familiar with the position of commonly prescribed (tmAbs) therapies at their institutions.

[Causes of Abnormal Hemoglobin Electrophoresis].

OBJECTIVE: To investigate the possible causes of abnormal hemoglobin electrophoresis results. METHODS: The hemoglobin electrophoresis results of 5 696 patients in the First Affiliated Hospital of Chengdu Medical College from September 2018 to July 2021 were collected, and the abnormal results and clinical significance were analyzed. RESULTS: The results of 486 patients (accounting for 8.53%) were abnormal, of which 300 cases had increased HbA2, 135 cases had decreased HbA2, 44 cases had increased F alone, and 7 cases had abnormal hemoglobin bands. Among the 486 patients, 246 patients were thalassemia gene positive (the positive rate was 50.62%), including 29 cases of α thalassemia, 208 cases of ß thalassemia and 9 cases of αß thalassemia. Among the patients with elevated HbA2, 68.67% were detected ß thalassemia, 3.00% αß thalassemia, 9.33% were suspected to be caused by macrocytosis, 6.33% by thyroid dysfunction, and 12.67% by uncertainty of the method. Among the patients with reduced HbA2, 21.48% were detected α thalassemia, 60.00% iron deficiency anemia, 8.15% were suspected to be caused by thyroid dysfunction, and 10.37% by uncertainty of the method. Among the patients with elevated F alone, the results of thalassemia gene detection were negative, 40.91% of them were suspected to be caused by macrocytosis, 27.27% by hereditary persistence of fetal hemoglobin, 29.55% by special physiological condition of pregnant women, and 2.27% by hyperthyroidism. Abnormal hemoglobin bands were detected in 7 patients, including 4 cases of hemoglobin D, 2 cases of hemoglobin E, and 1 case of hemoglobin J. CONCLUSION: Thalassemia, iron deficiency anemia, macrocytosis such as megaloblastic anemia and non-severe aplastic anemia, thyroid dysfunction, hereditary persistence of fetal hemoglobin, abnormal hemoglobin diseases, the uncertainty of the method are all important causes of abnormal hemoglobin electrophoresis results. In clinical work, the patient's indicators should be comprehensively analyzed to determine the possible cause.

Reference intervals for erythrocyte parameters and hemoglobin electrophoresis parameters for young children in Guangxi.

BACKGROUND: Erythrocyte parameter analysis is the important means for diagnosis and treatment of hematological diseases, which are essential for screening of thalassemia in southern China combined with hemoglobin electrophoresis analysis. But little is known regarding the reference intervals (RIs) in healthy pediatrics in these two areas. METHODS: 95% RIs of erythrocyte parameters were calculated from 853 healthy preschoolers, aged from 1 days to <6 years, according to the C28-A3C guidelines of the Institute of Clinical and Laboratory Standards. To express the magnitude of sex and age variation, standard deviation ratio (SDR) was calculated using ANOVA. Concurrently, we selected 3814 thalassemia carriers as carriers group and drew receiver operating characteristic (ROC) curves to establish the optimal cut-off values of hemoglobin electrophoresis parameters, which were used as the upper/lower limits of RIs to efficiently screen thalassemia. RESULTS: All parameters except red blood cell (RBC) required age partitioning, confirmed by SDRage above .4. There was no need for sex partitioning on all parameters, confirmed by SDRsex below .4. The optimal cut-off value of Hemoglobin A2 (Hb A2) in the four subgroups was <7.8% (Hb A), 2.3%-3.2%, 2.5%-3.6% and 2.6%-3.6%, respectively. CONCLUSION: In this study, the establishment of RIs improved the diagnostic efficiency of hematological disease (especially thalassaemia) for children in Guangxi. It provides reliable hematological references for the identification and diagnosis, treatment monitoring, and health screening of children's clinical diseases.

[Detection of paraprotein in plasma cell tumors].

Paraprotein is a laboratory biomarker of plasma cell tumors and other lymphoproliferative diseases. Its determination is necessary for diagnosing, monitoring and assessment of therapy effectiveness. The lecture presents the main methods of qualitative and quantative analysis of monoclonal proteins: gel electrophoresis, capillary electrophoresis, immunofixation and nephelometry features, possibilities and limitations are reviewed. The main sources of errors and artifacts during these studies are considered. Also the difficulties in the diagnosis and interpretation of the results of serum and urine tests are highlighted.