Case report: Interference from isatuximab on serum protein electrophoresis prevented demonstration of complete remission in a myeloma patient

Multiple myeloma is a haematological cancer caused by malignant plasma cells in the bone marrow that can result in organ dysfunction and death. Recent novel treatments have contributed to improved survival rates, including monoclonal antibody therapies that target the CD38 protein on the surface of plasma cells. Anti-CD38 therapies are IgG kappa monoclonal antibodies that are given in doses high enough for the drug to be visible on serum protein electrophoresis as a small paraprotein. We present a case where isatuximab, the most recent anti-CD38 monoclonal antibody to be approved for treatment of myeloma, obscured the patient’s paraprotein on gel immunofixation, so that complete remission could not be demonstrated. This was resolved using the isatuximab Hydrashift assay. The interference on gel immunofixation was unexpected because isatuximab migrated in a position distinct from the patient’s paraprotein on capillary zone electrophoresis. We demonstrate the surprising finding that isatuximab migrates in a different position on gel electrophoresis compared to capillary zone electrophoresis. It is vital that laboratories are aware of the possible interference on electrophoresis from anti-CD38 monoclonal antibody therapies, and are able to recognise these drugs on protein electrophoresis. The difference in isatuximab’s electrophoretic mobility on capillary and gel protein electrophoresis makes this particularly challenging. Laboratories should have a strategy for alternative analyses in the event that the drugs interfere with assessment of the patient’s paraprotein.

Elevated serum gamma globulins in apparently healthy Nigerians living in Ogbomoso: A possible manifestation of phagocytic dysfunction

Background: Serum protein electrophoresis abnormalities, particularly elevated gamma globulins (hypergammaglobulinemia), have been reported in apparently healthy Nigerians living in Ogbomoso and elsewhere. Since the mechanisms for this phenomenon have not been fully substantiated, we hypothesized that impaired neutrophil phagocytosis could contribute to this condition. Methods: Healthy humans exhibiting hypergammaglobulinemia (HGG) were identified using serum protein electrophoresis (SPE) performed on cellulose acetate gel in barbital buffer (pH 8.6). GelQuant image analysis and quantitation software were further employed to quantify gamma globulin fraction. Neutrophils were isolated from K3EDTA anticoagulated peripheral blood using neutrophil isolation histopaque of Kayman Chemical, USA. Neutrophil phagocytic activity was analyzed using a non-subjective commercial colorimetric phagocytosis assay kit obtained from Cell-Biolab Inc, USA. Results: The purity and viability of isolated neutrophils were approximately 94 % and 92 %, respectively. Ex-vivo phagocytic activity of neutrophils isolated from apparently healthy subjects exhibiting HGG, expressed in absorbance unit (AU), was 48.1±8.6 % which was significantly lower (p<0.05); compared to the controls (98.9±14.3 %). Conclusion: Since neutrophils play crucial roles in innate immune responses, impairment of neutrophil phagocytic activity may lead to persistent antigenic stimulations of the adaptive immune system. This could in turn orchestrate γ-globulins expression leading to HGG. Statement of novelty: We demonstrated a reduced neutrophil phagocytic activity as a possible basis for hypergammaglobulinemia in healthy Nigerians, perhaps for the first time.

Serum Protein Electrophoresis May Be Used as a Screening Tool for Antibody Deficiency in Children and Adolescents

BackgroundPatients with antibody deficiency may experience exceptionally long diagnostic delays, increasing the risk of life-threatening infections, end-organ damage, mortality, and health costs.ObjectiveThis study aimed to analyze serum protein electrophoresis and verify the correlation between calculated globulin (CG, total protein minus albumin levels) or electrophoretically determined serum gamma globulin fraction (Gamma) with IgG levels in children and adolescents under 18 years old (yo).MethodsWe analyzed serum protein electrophoresis (GC or Gamma) and IgG levels from 1215 children and adolescents under 18 yo, classified into 5 age groups. We verified the correlation between CG or Gamma with serum IgG levels.ResultsSerum IgG levels varied according to age groups (from 4.3 ± 2.3 g/l in children under 6 months old to 11.4 ± 3.2 g/l in adolescents in the 10-&lt;18 yo group). CG sensitivity and specificity to detect IgG below the reference range for all patients were 93.1% and 81.8%, respectively, and varied according to age group. Gamma sensitivity and specificity for all patients were 100% and 87.8%, respectively, and varied according to age group as well. We found serum IgG levels below the age reference level in 29 patients (2.4% of the cases) using CG or Gamma levels.ConclusionBoth CG and Gamma levels may be of utility as a screening tool for earlier diagnosis of antibody deficiency in children and adolescents under 18 yo.

Characterization of serum protein electrophoresis patterns and C-reactive protein in canine tick-borne diseases

Background and Aim: Canine tick-borne diseases are important diseases with a worldwide distribution. In Thailand, the most important canine tick-borne diseases are ehrlichiosis, babesiosis, and hepatozoonosis. This study aimed to determine the serum protein electrophoresis patterns (SPEPs) and C-reactive protein (CRP) levels associated with Ehrlichia canis, Babesia canis, or Hepatozoon canis single infections. Materials and Methods: A total of 650 canine blood samples were collected from animal hospitals and clinics in Bangkok and its vicinity to examine health status and blood parasite infection. Suspected blood parasite infections were examined by buffy coat thin blood smear and confirmed by polymerase chain reaction. Normal dog and positive E. canis, B. canis, and H. canis single infections and serum protein profiles were determined by agarose gel electrophoresis. CRP concentration was measured by fluorescent immunoassay. Results: In dogs infected with E. canis, B. canis, and H. canis single infections, albumin levels and A/G ratios significantly decreased, whereas β2-globulin levels increased (p<0.05). The γ-globulin level significantly increased in E. canis and H. canis infections (p<0.05). A monoclonal gammopathy pattern was observed in E. canis and B. canis single infections, whereas β-γ bridging patterns and increased β- and γ-globulin fractions were found in H. canis single infections. The CRP level increased in dogs with blood parasite single infections and may be related to the pathogenesis of the infection. Conclusion: SPEPs and CRP levels can be used to monitor health status and blood parasite problems in infected dogs.

In vitro evaluation of potential interference of lokivetmab with protein electrophoresis and immunofixation

Objective In humans, misdiagnoses of monoclonal gammopathy after use of therapeutic monoclonal antibodies has been documented. This triggers concerns for similar misdiagnoses in animals treated with monoclonal antibodies. The aim of this study was to evaluate if lokivetmab interferes with serum protein electrophoresis and immunofixation electrophoresis in dogs. Material and methods Residual sera from 25 client-owned, healthy blood donor dogs from 2 veterinary hospitals in Germany were used. The residual sera were analysed with serum protein electrophoresis and immunofixation electrophoresis before and after being spiked with lokivetmab at a concentration of 10 µg/ml (corresponding to the mean peak serum concentration after a subcutaneous injection of 2 mg/kg lokivetmab). Results No monoclonal gammopathy was observed on serum protein electrophoresis and all proteins had a normal distribution pattern without any pathologic bands on immunofixation electrophoresis. The absolute γ-globulin values of spiked samples, however, were significantly higher than in the native sera although they remained within the reference interval. No other globulin fractions were significantly different. Conclusion and clinical relevance This study suggests that lokivetmab at a dose of 2 mg/kg is not detected as a monoclonal peak on serum protein electrophoresis or immunofixation electrophoresis, and thus is unlikely to lead to a misdiagnosis of other diseases that are characterised by monoclonal gammopathies.

The Association between serum protein electrophoresis patterns and severity of patients infected with SARS-CoV-2 virus

Background:-The Coronavirus epidemic 2019 (COVID-19) is really a highly infectious sickness that is causing a huge danger to human life throughout the world. The induction of acute cytokine storm and immunosuppressive in COVID- 19 patients causes a rise in cytokines levels in the blood. Furthermore, the full extent of serum protein alterations in COVID-19 patients remains unclear. Patients and methods: -In a cross-sectional study, 80 SARS-CoV-2 virus-infected patients aged 18 to 80 were categorized according to severity of the infection and their serum protein electrophoresis assessment in relation to the severity of Covid-19. Results:-SPE for patients infected with the SARS-CoV-2 virus showed a significant difference in albumin, beta, and gamma and there was no significant relation with the α1 and α2 all in comparison between the subgroups themselves. Conclusion:-We conclude from the finding: albumin, beta, and gamma fractions showed a decrease in levels In conjunction with disease severity.

Bisalbuminemia: A Pathologist’s Insight of an Uncommon Phenomenon

Background The incidence of a bifid electrophoretic pattern in the albumin region on serum protein electrophoresis is an infrequent phenomenon. The availability of literature from India is scarce and is limited to case reports. Objective The aim of the study is to analyze the frequency of bisalbuminemia in an Indian referral facility. The study delved into their clinical associations. Material and Methods The retrospective case records of the patient from the departmental database were scrutinized. The study subjects were for an 8-year study period. Results There were about 39,900 serum electrophoresis performed in an 8-year study period. A total of 40 cases of bisalbuminemia were detected. The incidence in our cohort was 0.01%. Conclusion Bisalbuminemia, an overtly benign condition, is infrequent in Indian population although not rare. It is associated with several clinical disorders; however, the association seems to be plausibly coincidental.

Diagnosing Paraproteinemic Keratopathy: A Case Report

A 65-year-old man presented with bilateral, painless, progressive blurring of vision over 9 years. Slit-lamp examination revealed bilateral subepithelial corneal opacities in clusters located at the mid-periphery. Anterior segment optical coherence tomography, in vivo confocal microscopy (IVCM), serum protein electrophoresis, and molecular genetic testing were performed to evaluate the cause of corneal opacities. Anterior segment optical coherence tomography revealed a band-like, hyperreflective lesion in the Bowman layer and anterior stroma of both corneas. IVCM revealed hyperreflective deposits in the epithelium, anterior stroma, and endothelium. Serum protein electrophoresis identified the presence of paraproteins (immunoglobulin kappa), and molecular genetic testing revealed absence of mutations in the transforming growth factor beta-induced gene (<i>TGFBI</i>) and collagen type XVII alpha 1 gene (<i>COL17A1</i>). The ocular diagnosis of paraproteinemic keratopathy eventually led to a systemic diagnosis of monoclonal gammopathy of undetermined significance by our hematologist/oncologist. Paraproteinemic keratopathy is a rare differential diagnosis in patients with bilateral corneal opacities and therefore may be misdiagnosed as corneal dystrophy or neglected as scars. In patients with bilateral corneal opacities of unknown cause, serological examination, adjunct anterior segment imaging, and molecular genetic testing play a role in establishing the diagnosis.