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The antibody-related immune response is mediated by immunoglobulins (Igs), soluble circulating glycoproteins produced by activated B cells that, upon the recognition of specific epitopes on pathogen surfaces, activate, proliferate, and differentiate into antibody-secreting plasma cells. Although the antibodies are effectors of the humoral immune adaptive response, their overproduction in response to a dysregulated proliferation of clonal plasma cell production in tumoral conditions (i.e., multiple myeloma), enriches the serum and urinary matrices, assuming the crucial role of biomarkers. Multiple myeloma (MM) is a plasma cell dyscrasia characterized by the expansion and accumulation of clonally activated plasma cells in bone marrow, determining the release of high amounts of monoclonal component (MC) that can be detected as intact immunoglobulin (Ig), immunoglobulin fragments, or free light chains (FLCs). The importance of detecting biomarkers for the diagnosis, monitoring, and prognosis of diseases is highlighted by the international guidelines that recommend specific assays for the analysis of intact Igs and FLC. Moreover, a developed assay called Hevylite® allows for the quantification of immunoglobulins that are both involved (iHLC) and not involved (uHLC) in the tumor process; this is a fundamental aspect of following up the patient’s workup and evaluating the progression of disease, together with the treatments response. We here summarize the major points of the complex scenario involving monoclonal gammopathies and MM clinical management in view of advantages derived for the use of Hevylite®.

Objectives: To assess serum immunoglobulin G (IgG) subclasses in a cohort of systemic sclerosis (SSc) patients and to evaluate the influence of IgG subclasses in the main complications of the disease. Methods: The serum level of IgG subclasses was evaluated in 67 SSc patients and 48 healthy controls (HC), matched for sex and age. Serum samples were collected and measured IgG1–4 subclasses by turbidimetry. Results: SSc patients had lower median total IgG [9.88 g/l (IQR 8.18–11.42 g/l) vs. 12.09 g/l (IQR 10.24–13.54 g/l), p < 0.001], IgG1 [5.09 g/l (IQR 4.25–6.38 g/l) vs. 6.03 g/l (IQR 5.39–7.90 g/l), p < 0.001], and IgG3 [0.59 g/l (IQR 0.40–0.77 g/l) vs. 0.80 g/l (IQR 0.46–1 g/l), p < 0.05] serum levels compared to HC. The logistic regression analysis showed IgG3 as the only variable associated with the diffusing capacity of the lung for carbon monoxide (DLco) ≤60% of the predicted [OR 9.734 (CI 95%: 1.312–72.221), p < 0.05] and modified Rodnan skin score (mRSS) [OR 1.124 (CI 95%: 1.019–1.240), p < 0.05], anti-topoisomerase I [OR 0.060 (CI 95%: 0.007–0.535), p < 0.05], and IgG3 [OR 14.062 (CI 95%: 1.352–146.229), p < 0.05] as variables associated with radiological interstitial lung disease (ILD). Conclusion: SSc patients have reduced levels of total IgG and an altered IgG subclass distribution compared to HC. Moreover, SSc patients show different serum IgG subclasses profiles according to the main involvement of the disease.

The iPTH upper reference limit (URL) reported by our laboratory provider (Abbott Laboratories) at Tor Vergata University Hospital was evaluated by internal verification procedures as not representative of our population and resulting as underestimated. In this study, a new reference interval has been investigated and established by comparing a direct and an indirect method based on a statistical reduction from results stored in the laboratory database.For reference interval calculation from the healthy population, we analyzed a cohort of 100 blood donors (84% males and 16% females) screened with no bone-related and malabsorption diseases. We analyzed a cohort of 495 patients retrieved from more than 800 iPTH results by excluding subjects with pathological measurement for calcium, phosphorus, and creatinine for the reference interval evaluation. Patients with vitamin D results were included in the analysis. Vitamin D sufficiency status during the period from January to September 2020 was also evaluated by investigating 3,050 patients.The iPTH reference interval of a healthy blood donor population was measured as 25.2-109.1 pg/mL (2.7-11.6 pmol/L) at 2.5 and 97.5 distribution percentile. The iPTH reference interval from data stored in the laboratory database was 19.3-112.5 pg/mL (2.0-11.9 pmol/L). Furthermore, 60% of the whole population had prevalently insufficient vitamin D concentration (30 ng/dL;75 nmol/L). The impact of vitamin D concentration on the iPTH reference interval was measured for insufficient vitamin D (30 ng/dL;75 nmol/L) as 15.2-127.7 pg/mL (1.6-13.5 pmol/L), desirable vitamin D (30-40 ng/ml; 75-100 nmol/L) as 25.6-105 pg/mL (2.7-10.7 pmol/L) and optimal vitamin D (40 ng/ml;100 nmol/L) as 26.2-89.2 pg/mL (2.8-9.4 pmol/L), respectively.The URL reported in manufacturer datasheets likely refers to a normal population with non-pathological vitamin D levels. On the contrary, the considered population was mostly vitamin D insufficient, resulting in a URL shift. On this basis, we suggest describing in medical reports the iPTH range for vitamin D deficiency for diagnosis of primary hyperparathyroidism even when a specific vitamin D request is lacking. On the other hand, reporting optimal vitamin D-based iPTH reference interval could be clinically relevant in supplemented patients as a marker of treatment efficacy.

Glycated hemoglobin (HbA1c) measurement provides the most important medium to long-term marker of time-averaged glycemic status. Its relationship to clinical outcome in diabetes has been convincingly demonstrated for both type 1 and type 2 diabetes. The main HbA1c measurement methods for clinical routine are as follows: ion-exchange chromatography; affinity chromatography, capillary electrophoresis, immunoassay and enzymatic methods. In this study, we evaluated the analytical performances of a new HPLC instrument (Tosoh HLC-723 G11 in the VAR mode) in HbA1c analysis and compared it with a capillary electrophoresis instrument (Sebia Capillarys 2 Flex Piercing). HbA1c analysis was performed in parallel by both methods for 250 samples randomly chosen from healthy and diabetic subjects at 'Tor Vergata' University Hospital of Rome. Tosoh HLC-723 G11 showed good reproducibility for 10 days both in quality controls and in samples analyzed (%CV

Glycated hemoglobin (HbA

Background Glycated hemoglobin (HbA1c) provides a useful estimate of mean glycemia in patients with diabetes and is directly related to risks for diabetes complications. The aim of this study is to compare a capillary electrophoresis method and two high-performance liquid chromatography (HPLC) cation-exchange analyzers (Variant II (Bio-Rad Laboratories, Inc., Hercules, CA) and G8 (Tosoh Biosciences, San Francisco, CA)) to identify the most reliable method in Hb variants' presence. Methods Measurements of HbA1c were carried out in blood samples from 200 Tor Vergata Hospital patients, using G8 Tosoh, and from 107 San Filippo Neri Hospital patients, using Variant II Bio-Rad methods. All samples were analyzed by Capillarys 2 Flex Piercing (FP; Sebia, Lisses, France). Results There was a good concordance between the results of capillary electrophoresis and HPLC methods (R2 = 0.99, P < 0.0001 for G8 HPLC; R2 = 0.99, P < 0.0001 for Variant II HPLC). During the study, we observed that some Hb variants, HbS and HbD-Iran, can alter the HbA1c level. Conclusions Since the HbA1c test is now recommended for diagnosing diabetes, and minimal variation of the concentration affects the clinical therapy, it is very important that the results are reliable and interference-free. Capillarys 2-FP analyzer is suitable for this purpose and sometimes it showed some advantages with respect to the HPLC analyzers tested, especially when Hb variants are present.

Il diabete e diventato un’“epidemia globale”, come riportato dall’Organizzazione Mondiale della Sanita (OMS). L’emoglobina glicata (HbA1c), considerata una delle metodiche di elezione per la diagnosi di diabete, riflette la glicemia nel corso delle ultime 6–8 settimane. Valori elevati di HbA1c sono associati allo sviluppo di complicanze a lungo termine nel diabete sia di tipo 1 sia di tipo 2. Secondo le linee guida dell’OMS, valori di HbA1c ≥ 48 mmol/mol (6,5%) possono essere utilizzati per diagnosticare il diabete; attualmente questa raccomandazione non prevede differenze in base al genere. Lo scopo di questo studio e stato determinare valori di HbA1c in soggetti sani per verificare se vi sono differenze significative. Sono stati analizzati, mediante Capillarys 2-FP (Sebia, Lisses, Francia), 515 campioni di sangue ottenuti da donatori sani di etnia bianca caucasica afferenti all’Ospedale “San Filippo Neri” e al Policlinico Universitario “Tor Vergata”. I dati ottenuti hanno mostrato valori medi di HbA1c di 32,2 ± 4,0 mmol/mol per i maschi e 30 ± 3,8 mmol/mol per le femmine, con una differenza statisticamente significativa (p

BACKGROUND: Glycated hemoglobin (HbA(1c)) provides a useful estimate of mean glycemia in patients with diabetes and is directly related to risks for diabetes complications. The aim of this study is to compare a capillary electrophoresis method and two high‐performance liquid chromatography (HPLC) cation‐exchange analyzers (Variant II (Bio‐Rad Laboratories, Inc., Hercules, CA) and G8 (Tosoh Biosciences, San Francisco, CA)) to identify the most reliable method in Hb variants' presence. METHODS: Measurements of HbA(1c) were carried out in blood samples from 200 Tor Vergata Hospital patients, using G8 Tosoh, and from 107 San Filippo Neri Hospital patients, using Variant II Bio‐Rad methods. All samples were analyzed by Capillarys 2 Flex Piercing (FP; Sebia, Lisses, France). RESULTS: There was a good concordance between the results of capillary electrophoresis and HPLC methods (R (2) = 0.99, P < 0.0001 for G8 HPLC; R (2) = 0.99, P < 0.0001 for Variant II HPLC). During the study, we observed that some Hb variants, HbS and HbD‐Iran, can alter the HbA(1c) level. CONCLUSIONS: Since the HbA(1c) test is now recommended for diagnosing diabetes, and minimal variation of the concentration affects the clinical therapy, it is very important that the results are reliable and interference‐free. Capillarys 2‐FP analyzer is suitable for this purpose and sometimes it showed some advantages with respect to the HPLC analyzers tested, especially when Hb variants are present.