Publications by authors named "Sara Altinier"

24 Publications

  • Page 1 of 1

Serum Free Light Chains in Common Variable Immunodeficiency Disorders: Role in Differential Diagnosis and Association With Clinical Phenotype.

Front Immunol 2020 31;11:319. Epub 2020 Mar 31.

Department of Medicine-DIMED, University of Padova, Padova, Italy.

We report on an observational, multicenter study of 345 adult CVID patients, designed to assess the diagnostic value and the clinical association of serum free light chain (sFLC) pattern in Common Variable Immunodeficiency disorders (CVID). Sixty CVID patients were tested twice in order to assess intraindividual variability of sFLC. As control groups we included 138 patients affected by undefined primary antibody defects (UAD), lymphoproliferative diseases (LPDs), and secondary antibody deficiencies not related to hematological malignancies (SID). CVID patients presented lower κ and λ chain concentration compared to controls, showing low intraindividual sFLC variability. On the basis of the sFLC pattern, patients were classified into four groups: κ-λ+, κ+λ-, κ-λ-, κ+λ+. The most common pattern in CVID patients was κ-λ- (51%), followed by κ-λ+, (25%), κ+λ+ (22%), and κ+λ- (3%). In UAD, LPD, and SID groups κ+λ+ was the most common pattern observed. By analyzing the possible association between sFLC patterns and disease-related complications of CVID, we observed that patients belonging to the κ-λ- group presented more commonly unexplained enteropathy compared to the κ+λ+ group and showed higher frequency of bronchiectasis and splenomegaly compared to both the κ-λ+ and κ+λ+ patients. When compared to the other groups, κ-λ- had also lower serum IgG, IgA, and IgM concentrations at diagnosis, lower frequency of CD27+IgD-IgM- switched memory B cells, and higher frequency of CD21 B cells, receiving earlier CVID diagnosis. Thus, lower levels of sFLC might be an epiphenomenon of impairment in B cell differentiation, possibly leading κ-λ- patients to a higher risk for bacterial infections and chronic lung damage. Based on these results, we suggest adding sFLC assay to the diagnostic work-up of hypogammaglobulinemia and during follow-up. The assay may be useful to differentiate CVID from other causes of hypogammaglobulinemia and to early detect monoclonal lymphoproliferation occurring over years. Moreover, since the sFLC pattern seems to be related to disease phenotypes and clinical manifestations of CVID and after confirmation by further studies, sFLC assay might be considered a promising prognostic tool for identifying patients at higher risk of developing enteropathy and chronic lung damage or splenomegaly. This will allow designing a tailored follow-up for CVID patients.
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http://dx.doi.org/10.3389/fimmu.2020.00319DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7136404PMC
March 2021

Prothrombin Is Responsible for the Lupus Cofactor Phenomenon in a Patient with Lupus Anticoagulant/Hypoprothrombinemia Syndrome.

TH Open 2020 Jan 9;4(1):e40-e44. Epub 2020 Mar 9.

Cardiology Clinic, Thrombosis Centre, Department of Cardiac, Thoracic and Vascular Sciences, University of Padua, Padova, Italy.

Lupus anticoagulant is a misnomer as it is commonly associated with thromboembolic events. In few cases, the name retains its literal meaning when it characterizes patients with a bleeding disorder. We describe a patient with lupus anticoagulant, hypoprothrombinemia, and major bleeding (lupus anticoagulant/hypoprothrombinemia syndrome). Immunological studies revealed a huge amount of circulating monoclonal immunoglobulin M lambda (IgMλ) antiphosphatidylserine/prothrombin antibodies (14,400 U/mL). Affinity purified monoclonal antibodies (440 U/mL) prolonged the coagulation time of normal plasma by 12.2 seconds (diluted Russell viper venom time) and 25.5 seconds (silica clotting time). The original patient's plasma mixed 1:1 with normal plasma showed a marked prolongation of coagulation times (lupus cofactor) from a ratio of 2.94 to 5.23 in diluted Russel viper venom time and from 2.30 to 3.00 using the silica clotting time. Human prothrombin added to original patient's plasma caused a marked prolongation of coagulation times in diluted Russell viper venom test thus unequivocally explaining the lupus cofactor phenomenon. In conclusion, we have shown that lupus anticoagulant/hypoprothrombinemia syndrome is attributable to monoclonal IgMλ antibodies directed to phosphatidylserine/prothrombin and that prothrombin is the protein responsible for the observed lupus cofactor phenomenon.
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http://dx.doi.org/10.1055/s-0040-1705091DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7062548PMC
January 2020

An international multi-center serum protein electrophoresis accuracy and M-protein isotyping study. Part II: limit of detection and follow-up of patients with small M-proteins.

Clin Chem Lab Med 2020 03;58(4):547-559

Division of Clinical Biochemistry and Immunology, Department of Laboratory Medicine and Pathology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.

Background Electrophoretic methods to detect, characterize and quantify M-proteins play an important role in the management of patients with monoclonal gammopathies (MGs). Significant uncertainty in the quantification and limit of detection (LOD) is documented when M-proteins are <10 g/L. Using spiked sera, we aimed to assess the variability in intact M-protein quantification and LOD across 16 laboratories. Methods Sera with normal, hypo- or hyper-gammaglobulinemia were spiked with daratumumab or elotuzumab, with concentrations from 0.125 to 10 g/L (n = 62) along with a beta-migrating sample (n = 9). Laboratories blindly analyzed samples according to their serum protein electrophoresis (SPEP)/isotyping standard operating procedures. LOD and intra-laboratory percent coefficient of variation (%CV) were calculated and further specified with regard to the method (gel/capillary electrophoresis [CZE]), gating strategy (perpendicular drop [PD]/tangent skimming [TS]), isotyping (immunofixation/immunosubtraction [ISUB]) and manufacturer (Helena/Sebia). Results All M-proteins ≥1 g/L were detected by SPEP. With isotyping the LOD was moderately more sensitive than with SPEP. The intensity of polyclonal background had the biggest negative impact on LOD. Independent of the method used, the intra-laboratory imprecision of M-protein quantification was small (mean CV = 5.0%). Low M-protein concentration and high polyclonal background had the strongest negative impact on intra-laboratory precision. All laboratories were able to follow trend of M-protein concentrations down to 1 g/L. Conclusions In this study, we describe a large variation in the reported LOD for both SPEP and isotyping; overall LOD is most affected by the polyclonal immunoglobulin background. Satisfactory intra-laboratory precision was demonstrated. This indicates that the quantification of small M-proteins to monitor patients over time is appropriate, when subsequent testing is performed within the same laboratory.
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http://dx.doi.org/10.1515/cclm-2019-1105DOI Listing
March 2020

An international multi-center serum protein electrophoresis accuracy and M-protein isotyping study. Part I: factors impacting limit of quantitation of serum protein electrophoresis.

Clin Chem Lab Med 2020 03;58(4):533-546

Division of Clinical Biochemistry and Immunology, Department of Laboratory Medicine and Pathology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.

Background Serum protein electrophoresis (SPEP) is used to quantify the serum monoclonal component or M-protein, for diagnosis and monitoring of monoclonal gammopathies. Significant imprecision and inaccuracy pose challenges in reporting small M-proteins. Using therapeutic monoclonal antibody-spiked sera and a pooled beta-migrating M-protein, we aimed to assess SPEP limitations and variability across 16 laboratories in three continents. Methods Sera with normal, hypo- or hypergammaglobulinemia were spiked with daratumumab, Dara (cathodal migrating), or elotuzumab, Elo (central-gamma migrating), with concentrations from 0.125 to 10 g/L (n = 62) along with a beta-migrating sample (n = 9). Provided with total protein (reverse biuret, Siemens), laboratories blindly analyzed samples according to their SPEP and immunofixation (IFE) or immunosubtraction (ISUB) standard operating procedures. Sixteen laboratories reported the perpendicular drop (PD) method of gating the M-protein, while 10 used tangent skimming (TS). A mean percent recovery range of 80%-120% was set as acceptable. The inter-laboratory %CV was calculated. Results Gamma globulin background, migration pattern and concentration all affect the precision and accuracy of quantifying M-proteins by SPEP. As the background increases, imprecision increases and accuracy decreases leading to overestimation of M-protein quantitation especially evident in hypergamma samples, and more prominent with PD. Cathodal migrating M-proteins were associated with less imprecision and higher accuracy compared to central-gamma migrating M-proteins, which is attributed to the increased gamma background contribution in M-proteins migrating in the middle of the gamma fraction. There is greater imprecision and loss of accuracy at lower M-protein concentrations. Conclusions This study suggests that quantifying exceedingly low concentrations of M-proteins, although possible, may not yield adequate accuracy and precision between laboratories.
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http://dx.doi.org/10.1515/cclm-2019-1104DOI Listing
March 2020

Free light chains in cerebrospinal fluid of multiple sclerosis patients negative for IgG oligoclonal bands.

Clin Chim Acta 2019 Sep 21;496:117-120. Epub 2019 Jun 21.

Department of Laboratory Medicine, University-Hospital of Padova, Via Giustiniani 2, 35128 Padova, Italy.

The detection of IgG oligoclonal bands (OCBs) in cerebrospinal fluid (CSF) is, as yet, the recommended biochemical marker for the diagnosis of multiple sclerosis (MS). Aim of this study was to investigate the behaviour of free light chains (FLC) in OCBs negative (OCBs-) MS patients compared with that in OCBs positive (OCBs+) MS patients and in a control group (CG) of subjects without cerebrospinal inflammatory disease. At multiple comparisons between the three groups, statistically significant differences (p < .001 for all) were found for κFLC. Conversely, λFLC values evidenced a greater overlapping in the three groups. Receiver operating characteristics (ROC) curves made with κFLC values, evidenced the greater differences of areas under curves (AUCs) between OCBs- and OCBs+ (AUCs: κFLC 0.98, QκFLC 0.98, κFLC index 0.96) with respect to the differences between OCBs- and CG (AUCs: κFLC 0.77, QκFLC 0.86, κFLC index 0.77): indeed >50% of MS OCBs- subjects studied evidenced the same values of κFLC, QκFLC and κFLC index found in CG. Conversely, if the aim is to select MS subjects while avoiding undertaking the more complex isoelectrofocusing test, values with absolute specificity for MS (QκFLC = 15, sensitivity = 0.76 and κFLCindex = 3.09, sensitivity = 0.72) could be used. The values found in this study call for confirmation with data from more subjects, including those with other CSF inflammatory diseases. Anyway, the most important finding was that, for some OCBs- subjects, κFLC are more effective than OCBs in diagnosing MS.
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http://dx.doi.org/10.1016/j.cca.2019.06.016DOI Listing
September 2019

Idelalisib plus rituximab is effective in systemic AL amyloidosis secondary to chronic lymphocytic leukaemia.

Hematol Oncol 2018 Feb 3;36(1):366-369. Epub 2017 Oct 3.

Hematology and Clinical Immunology Unit, Department of Medicine, University of Padua, Padua, Italy.

Light chain amyloidosis is characterized by the progressive deposition of immunoglobulin light chains into the extracellular tissue, leading to organ dysfunction. Usually, it is associated with an underlying clonal plasma cell dyscrasia and rarely with chronic lymphocytic leukaemia. Herein, we described the first report of a patient with relapsed chronic lymphocytic leukaemia harbouring TP53 abnormalities who developed, histologically proven, systemic light chain amyloidosis who was treated with the PI3K inhibitor, idelalisib, and rituximab. Unfortunately, the patient had sudden death during sleep, likely caused by arrhythmia secondary to amyloid cardiomyopathy. Idelalisib was at least effective in reducing secretory free light chain, chronic lymphocytic leukaemia burden, and to improve the survival of patient.
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http://dx.doi.org/10.1002/hon.2480DOI Listing
February 2018

Free light chains and heavy/light chains in monitoring POEMS patients.

Clin Chem Lab Med 2016 Jun;54(6):1065-71

Background: POEMS syndrome is defined by Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal gammopathy and Skin changes. The vascular endothelial growth factor (VEGF) appears to play a key role in the pathogenesis of the syndrome, and its concentrations are deemed to correlate to disease activity. The aim of the present study was to verify whether other biochemical markers including serum free light chains (FLC) and heavy/light chains (HLC) would be of value in monitoring POEMS patients.

Methods: Fifty-three serum samples were collected from seven POEMS patients at diagnosis and during a follow-up period (range 14-56 months). VEGF was measured using an ELISA method, while FLC and HLC concentrations were measured using Binding Site reagents on a BNII (Siemens) nephelometer.

Results: At diagnosis all patients presented high VEGF concentrations, while the κ/λFLC ratio (FLCr) was within the reference range. Four patients had abnormal HLC, HLCκ/HLCλ (HLCr) and FLC values. The relationship between the trend of VEGF and both HLC and FLC during the follow-up was analysed by means of Cohen's κ coefficient. VEGF and HLC values displayed a significant κ-Cohen (0.537, p=0.002) in all chemotherapy-responder patients while in non-responders it did not. Conversely, in both responders and non-responders, VEGF and FLC values did not attain a significance on κ-Cohen analysis. In three out of four responders HLCr values increased, thus reflecting an improved clinical condition.

Conclusions: The findings made in the present study indicate that HLC, either as intact immunoglobulin or as HLCr, may provide useful information, particularly in identifying responders and confirm that the role of FLC is unreliable in monitoring patients with POEMS syndrome.
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http://dx.doi.org/10.1515/cclm-2015-0910DOI Listing
June 2016

An IgE multiple myeloma: contradictory findings in clinical laboratory testing.

Clin Chim Acta 2013 Oct 17;425:114-6. Epub 2013 Jul 17.

Department of Laboratory Medicine, University-Hospital of Padova, Italy. Electronic address:

Background: IgE multiple myeloma is a rare kind of plasma cell disorder, characterized by an aggressive clinical course, where laboratory testing plays a fundamental role for the correct diagnosis in order to start a targeted therapy. In the present paper it is described a case of IgE myeloma where contradictory findings between immunometric and separative techniques were found.

Materials And Methods: Serum and 24h urine samples were tested using electrophoresis and immunofixation electrophoresis employing IgE antiserum and IgE were quantified using an immunometric method.

Results: Serum immunofixation evidenced a monoclonal band ascribable to IgE lambda and IgE serum concentration was 1,364,00 kU/L. Urine electrophoresis evidenced a band compatible with IgE, and urine concentration was 2715 kU/L. On the contrary in the immunofixation of the urine sample no band reacting with IgE antiserum was found.

Conclusions: Considering that the immunometric method measured IgE in urine sample and the electrophoresis of urine sample evidenced a band compatible with IgE, the explanation could be that during renal filtration or because of some characteristics related to urine matrix, the immunoglobulin IgE could had been modified in the site recognized by the antiserum used in immunofixation, and not in the one used in the immunometric method.
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http://dx.doi.org/10.1016/j.cca.2013.07.006DOI Listing
October 2013

Multicenter evaluation of hemoglobin A1c assay on capillary electrophoresis.

Clin Chim Acta 2013 Sep 20;424:207-11. Epub 2013 Jun 20.

Department of Laboratory Medicine, University Hospital of Padova, Via Giustiniani 2, 35128 Padova, Italy.

Background: Hemoglobin A1c (HbA1c) measurement is currently used for the routine monitoring of long-term glycemic status, thus playing a fundamental role in the management of this disease. Since this marker has recently been recommended as an additional tool for diagnosing diabetes, it's of the utmost importance to ensure that the precision and accuracy of HbA1c methods are satisfactory.

Methods: We assessed the analytical performances of the Capillarys 2 Flex Piercing® analyzer and compared the results obtained with those from two other widely used HPLC instruments. Furthermore, we evaluated the convenience and ergonomics of the system in authentic routine work conditions in three centers.

Results: Within-laboratory (n=40) and between-laboratory (n=120) imprecision CV% using four blood samples with different concentrations of HbA1c were <3.4% and <3.1% using IFCC units and <2.1% and <2.0% using NGSP units, respectively. The obtained trueness (<3 mmol/mol, <0.3%) was highly satisfactory, nor was HbA1c measurement compromised by the presence of the commonly present hemoglobinopathies. The comparison made with established methods revealed excellent agreement (r>0.985).

Conclusions: The evaluated method is precise, accurate and robust, with a high throughput. It also allows the identification of the most frequent Hb variants and therefore may be a valid alternative to other methods currently proposed for routine use in clinical laboratories.
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http://dx.doi.org/10.1016/j.cca.2013.06.014DOI Listing
September 2013

Serum free light chain reference values: a critical approach.

Clin Biochem 2013 May 4;46(7-8):691-3. Epub 2013 Feb 4.

Department of Laboratory Medicine, University-Hospital of Padova, Italy.

Objectives: The clinical usefulness of serum free light chain (FLC) measurement in the management of patients with plasma cell proliferative disorders has been reported in several papers, and most clinical studies use the reference ranges declared by the manufacturer. The aim of the present study was to evaluate the reproducibility of FLCs immunoassay and to validate the reference range, before introducing it in routine setting.

Design And Methods: Internal quality control materials and a pool of fresh serum samples were used to evaluate imprecision; 162 fresh sera from healthy blood donors were analyzed to evaluate the reference range for FLCs. In order to verify the κ/λ FLC ratio, 43 sera from patients with polyclonal hypergammaglobulinemia were tested. The FLC immunoassay was performed using a nephelometer with the Freelite reagents.

Results: The imprecision studies performed using a serum pool tested with two different lots of reagents showed a mean CV of 16.09% for κFLC and of 16.72% for λFLC. Lower CV%s and different mean values were found by calculating the results from each specific lot separately, while different results were obtained using the control materials provided by the manufacturer. In reference subjects, the 2.5-97.5th percentiles were found to be 4.52-22.33 and 4.84-21.88mg/L for κFLC and λFLC, respectively. The range for κ/λ ratio (0.65-2.36) was validated with the values obtained from subjects with polyclonal hypergammaglobulinemia. In retesting 15 samples from blood donor subjects with a different lot of reagents, mean bias percentages of 17.60 for κFLC and 15.26 for λFLC were obtained.

Conclusions: These findings confirm the lot-to-lot variability of the FLC assays also in the measurement of polyclonal light chains, as well as the need to carefully validate the reference values.
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http://dx.doi.org/10.1016/j.clinbiochem.2013.01.014DOI Listing
May 2013

Identification and quantification of hemoglobins in whole blood: the analytical and organizational aspects of Capillarys 2 Flex Piercing compared with agarose electrophoresis and HPLC methods.

Clin Chem Lab Med 2013 Apr;51(4):791-7

Department of Laboratory Medicine , University-Hospital of Padova, Via Giustiniani 2 35128 Padova, Italy.

Background: The present study was conducted to evaluate the analytical performance and the organizational aspects of Capillarys 2 Flex Piercing system (CFP) respect to agarose electrophoresis and HPLC methods in hemoglobinopathies screening.

Methods: The measurement of imprecision in HbA 2 and HbF quantification was verified on HbA 2 CFP control and on three samples; 74 whole blood samples were used to evaluate migration time imprecision of hemoglobin variants S, C and E (HbS, HbC, and HbE); to compare methods, 451 samples were tested on CFP and HPLC; reference values were verified as value distribution in 160 blood donors and at ROC curve analysis on 449 samples from routine analysis.

Results: Imprecision: the analytical CV % s ranged from 1.25 to 3.9 at HbA 2 quantification, the CV % was 3.78 at HbF quantification; the running time imprecision for HbS and HbC and HbE ranged from 0.20 to 0.69 % . Method comparison: at regression analysis findings were HbA 2: CFP=1.21×HPLC–0.64, HbF: CFP=1.31×HPLC−0.75, HbS: CFP=1.10×HPLC−3.24. Reference values: the HbA 2 95th percentile range was 2.5–2.8; HbF was undetectable in 154 out 160 samples tested; at ROC curve analysis the best combination of sensitivity and diagnostic efficiency was obtained using 2.2 and 3.0, as reference values, for HbA 2 and 1.1 as the upper reference limit for HbF. Organizational aspects: with respect to the procedures currently implemented in our laboratory CFP requires 2 h less time and obviates the need for some manual steps.

Conclusions: The quantification, reproducibility and diagnostic efficiency provided by CFP in identification and quantification of hemoglobins appear accurate. In addition, the use of primary tubes allows improved safety, and the avoidance of some manual steps, that prolong working time and are a source of possible errors.
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http://dx.doi.org/10.1515/cclm-2012-0061DOI Listing
April 2013

Heterophilic antibody interference in a non-endogenous molecule assay: an apparent elevation in the tacrolimus concentration.

Clin Chim Acta 2009 Apr 25;402(1-2):193-5. Epub 2008 Dec 25.

Department of Laboratory Medicine University-Hospital of Padova, Italy.

Background: In drug monitoring assays the most common interferences are due to hematocrit, other drugs or their metabolites, while the interference by heterophilic antibodies has been reported only when measuring endogenous molecules. In the present paper a heterophilic antibody interference in the tacrolimus measurement is described.

Methods: Samples from a patient treated with tacrolimus were analyzed on RxL Dimension analyzer. Ranging drug concentrations from 49 to 12.5 microg/L, even after the interruption of the treatment, confirmation analysis were performed using heterophilic blocking tubes before tacrolimus measurement on the same analyzer, then testing the samples on V-Twin System, finally incubating the samples with chlorophenol red beta-d-galactopyranoside, beta-galactosidase, polyclonal mouse IgG, protein A and Protein G resin.

Results: The elevated tacrolimus concentrations were due to the presence of an interference attributable to heterophilic antibodies, as confirmed by treating the samples with heterophilic blocking tubes and protein G resin.

Conclusions: a) The interference caused by heterophilic antibodies can be found not only in immunoassays measuring endogenous molecules, but also in those for exogenous molecules; b) the pre-treatment sample procedure, which represent the main difference between the methods affected and unaffected by the interference, is a fundamental step in removing the antibodies responsible of the interference.
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http://dx.doi.org/10.1016/j.cca.2008.12.021DOI Listing
April 2009

An expert system for the classification of serum protein electrophoresis patterns.

Clin Chem Lab Med 2008 ;46(10):1458-63

Department of Laboratory Medicine, University Hospital of Padova, Padova, Italy.

Background: With the improvement of capillary electrophoresis, much progress has been made in terms of sensitivity and automation, but the interpretation of the patterns, actually, depends totally on expert personnel. The aim of this work was to evaluate Neurosoft-Sebia, an expert system developed to discriminate between regular and anomalous serum protein electrophoresis patterns performed on Capillarys2.

Methods: Neurosoft-Sebia, based on six auto-associative neural networks, was trained to create the initial knowledge base. In the tuning phase, 3000 electrophoretic patterns were performed in three different laboratories, and the discordances between human experts and Neurosoft-Sebia classifications were added to the initial knowledge base. Finally, the performances of Neurosoft-Sebia were evaluated using a benchmark dataset.

Results: The initial knowledge base was created with 2685 fractions. In the tuning phase, 241 discordances were found: 56 as regular by Neurosoft-Sebia and anomalous by human experts, and 185 as anomalous by Neurosoft-Sebia and regular by human experts. Sensitivity values were evidenced as the ability of Neurosoft-Sebia in selecting anomalous fractions, with an increase from 66.67% using the initial knowledge base to 97.40% using the enriched knowledge base.

Conclusions: This work demonstrated how the ability of Neurosoft-Sebia in selecting anomalous pattern was comparable to that of human experts, saving time and providing rapid and standardized interpretations.
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http://dx.doi.org/10.1515/CCLM.2008.284DOI Listing
December 2008

Analytical and clinical performance of a fully automated cardiac multi-markers strategy based on protein biochip microarray technology.

Clin Biochem 2007 Nov 10;40(16-17):1245-51. Epub 2007 Aug 10.

Department of Laboratory Medicine, University-Hospital of Padova, Via Giustiniani 2, 35128 Padova, Italy.

Objectives: The analytical and clinical performance of the Evidence Cardiac Panel were evaluated.

Design And Methods: The Evidence Cardiac Panel, an automated protein biochip microarray system, allows the simultaneous determination of creatine kinase MB (CK-MB), myoglobin (MYO), glycogen phosphorylase BB (GPBB), heart-type fatty acid-binding protein (H-FABP), carbonic anhydrase III (CA III), cardiac troponin I (cTnI). Precision: 3 levels of quality control (QC) and 2 in house pools (P) were assayed. Method comparison: MYO and cTnI concentrations measured on Evidence (E) and on Dimension RxL (D) analyzers were compared. Clinical study: 132 non-consecutive patients admitted to the Emergency Department for chest pain were enrolled.

Results And Conclusions: The between-day imprecision was CK-MB=6.80-10.08%; MYO=5.36-16.50%; GPBB=6.51-12.12%; H-FABP=6.26-12.63%; CA III=6.98-13.61%; cTnI=6.02-9.80%. Method comparison: E-MYO vs. D-MYO, Bias=-29.22, 95% CI from -40.25 to -18.18; E-cTnI vs. D-cTnI, Bias=-2.75, 95% CI from -4.04 to -1.46. In patients studied (at discharge: AMI, acute myocardial infarction n=42; non-AMI, n=90) H-FABP showed the highest accuracy (ROC analysis, AUC=0.92) and "cTnI+H-FABP" the greatest diagnostic efficacy (89.4%) in AMI diagnosis.
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http://dx.doi.org/10.1016/j.clinbiochem.2007.07.018DOI Listing
November 2007

New biochemical markers: from bench to bedside.

Clin Chim Acta 2007 May 22;381(1):14-20. Epub 2007 Feb 22.

Department of Laboratory Medicine, University-Hospital of Padova, Italy.

Background: Evaluation of patients presenting to hospital with chest pain or other signs or symptoms suggesting acute coronary syndrome (ACS) is problematic, time-consuming and sometimes expensive, even if new biochemical markers, such as troponins, have improved the ability to detect cardiac injury. However, patients with normal troponin values are not necessarily risk-free for major cardiac events.

Methods: Recent investigations indicate that the overall patient risk may be assessed earlier than before, thanks to new knowledge acquired concerning the pathobiology of atherosclerosis and molecular events involved in the progression of disease, thus allowing the development of new biochemical markers. Some selected markers are released during the different phases of development of cardiovascular disease and may be useful for the diagnosis of patients with cardiovascular disease. In particular, the identification of emerging markers that provide relevant information on the inflammatory process, and the development of biomarkers whose circulating concentrations suggest the status of plaque instability and rupture, seems to be of particular value in prognosis and risk stratification. The overall expectations for a cardiovascular biochemical marker are not only its biological plausibility but also the availability at a reasonable cost of rapid, high quality assays, and their correct interpretation by clinicians using optimal cut-offs.

Conclusion: The crossing from bench to bedside for each new marker discovered, must be associated with concurrent advances in the characterization of analytical features and the development of routine assay, in the assessment of analytical performance and in interpretative reporting of test results as well as in the training of physicians to use the array of biomarkers available appropriately and to interpret them correctly. This approach calls for the coordinated support of clinicians, technology experts, statisticians and the industry so that new biochemical developments can be of optimal value.
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http://dx.doi.org/10.1016/j.cca.2007.02.028DOI Listing
May 2007

High-sensitivity C-reactive protein in umbilical cord of small-for-gestational-age neonates.

Neonatology 2007 29;91(3):186-9. Epub 2006 Nov 29.

Neonatal Intensive Care Unit, Department of Pediatrics, Medical School, University of Padova - Padova Hospital, Azienda Ospedaliera, Padova, Italy.

Background: Several epidemiological studies reported a significant correlation between low birth weight and cardiovascular disease in adult life. Recent studies showed that an inflammatory response has been associated with the development of atherosclerosis. High-sensitivity C-reactive protein (hs-CRP) has been demonstrated to be a sensitive marker of this inflammatory process giving prognostic information in apparently healthy general population as well as in patients with symptomatic atherosclerosis. We hypothesized that the chronic inflammatory process, involved in the future atherosclerotic injury, could be found during the fetal period.

Objectives: To compare umbilical cord hs-CRP concentrations between small-for-gestational-age (SGA) and appropriate-for-gestational age (AGA) neonates.

Methods: Concentrations of hs-CRP (Dade Boehring) were measured in 35 SGA infants (gestational age: mean +/- SD, 34.6 +/- 3.0 weeks) and in 69 AGA neonates (34.2 +/- 3.4 weeks). Neonates with a history of suspected or proven feto-maternal infection were excluded.

Results: In SGA infants, hs-CRP concentrations were significantly higher than in AGA neonates: median (range); 0.06 mg/l (0.02-5.53) vs. 0.02 mg/l (0.02-0.55); p = 0.003. Concentrations of hs-CRP were higher than the detection limit (0.04 mg/l) in 25 (71.5%) SGA infants and in 28 (40.6%) AGA neonates (p = 0.002).

Conclusions: In SGA infants, hs-CRP concentrations are higher than in AGA neonates suggesting the presence of an inflammatory process in this group of patients during the fetal life. This finding could be involved in the previously reported relationship between low birth weight and cardiovascular disease in adult life.
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http://dx.doi.org/10.1159/000097451DOI Listing
May 2007

Analytical and clinical evaluation of a new heart-type fatty acid-binding protein automated assay.

Clin Chem Lab Med 2006 ;44(11):1383-5

Department of Laboratory Medicine, University Hospital of Padova, Padova, Italy.

Background: The accurate and rapid recognition of myocardial injury in patients presenting in the emergency department (ED) with chest pain continues to be a clinical challenge. Heart-type fatty acid-binding protein (H-FABP) appears to be one of the best candidates among the new early cardiac markers studied.

Methods: We evaluated the analytical characteristics of a new quantitative and fully automated H-FABP assay (Randox Laboratories Ltd., Crumlin, UK) and compared its clinical performance with respect to the myoglobin (Myo) assay (Dade Behring, Milan, Italy). A precision study was carried out by testing three levels of quality control (QC) material and two in-house pool (P) samples. To test the accuracy of H-FABP determinations in plasma (lithium-heparin) samples, H-FABP concentrations measured in a set of matched sera and plasma samples were compared. A total of 77 non-consecutive patients (51 males and 26 females; 62+/-16 years) who presented to the ED with chest pain suggesting myocardial ischemia were enrolled. The patients were classified into two groups (acute myocardial infarction, n=22; non-acute myocardial infarction, n=55) on the basis of the discharge diagnosis.

Results: The between-day imprecision for three levels of control material and serum pool samples was 6.26%-8.04% (range 2.32-44.03 microg/L) and 9.03%-12.63% (range 11.85-65.13 microg/L), respectively. In the serum vs. plasma study, bias was +0.178 (95% CI -0.033 to +0.389). The best cut-off and the associated diagnostic efficacy were 95 microg/L and 89.47% for Myo and 5.09 microg/L and 98.70% for H-FABP, respectively.

Conclusions: H-FABP determination in patients with ischemic symptoms may be a more reliable early indication of cardiac damage than myoglobin.
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http://dx.doi.org/10.1515/CCLM.2006.246DOI Listing
January 2007

Innotrac Aio!: a point-of-care or a routine analyzer? Analytical performance and plasma/whole blood comparison.

Clin Chem Lab Med 2006 ;44(10):1278-82

Department of Laboratory Medicine, University-Hospital of Padova, Padova, Italy.

Background And Methods: The aim of the present study was to evaluate the analytical performance of the Innotrac Aio! analyzer in measuring the cardiac markers troponin I (TnI), myoglobin (Myo) and creatine kinase-MB (CK-MB), both in lithium heparin plasma and in whole blood.

Results: TnI analytical sensitivity was 0.012 microg/L and the concentration corresponding to CV=10% was 0.036 microg/L. In healthy subjects, the 99th percentile TnI values were 0.023 and 0.016 microg/L in whole blood and in plasma, respectively. One hundred samples were tested both in whole blood and in plasma: TnI-whole-blood=1.16-plasma+0.011, bias=+0.18 (95% CI from -0.22 to +0.59); Myo-whole-blood=1.04-plasma-1.93, bias=+1.08 (95% CI from -6.17 to +8.32); CK-MB-whole-blood=1.11-plasma-0.09, bias=+0.96 (95% CI from -0.53 to +2.45). The method comparison with the RxL Dimension analyzer for TnI and Myo gave the following results: TnI Aio!=0.30 TnI RxL+0.00; bias=-5.80 (95% CI from -7.81 to -3.78), Myo Aio!=1.33 Myo RxL+0.42, bias=+53.09 (95% CI from +38.44 to +67.74).

Conclusions: The analytical performance of the Innotrac Aio! analyzer was satisfactory for all three cardiac markers evaluated and, in particular, the TnI method provided sensitive and accurate results. The most important finding in this study is the possibility to perform the tests as either routine or point-of-care analysis, thus overcoming the variability of results obtained employing different methods.
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http://dx.doi.org/10.1515/CCLM.2006.223DOI Listing
January 2007

Cardiac troponin I in asphyxiated neonates.

Biol Neonate 2006 17;89(3):190-3. Epub 2005 Nov 17.

Department of Pediatric, Medical School, University of Padova, Azienda Ospedaliera di Padova, Padova, Italy.

Background: Cardiac troponins T (cTnT) and I (cTnI) are well-established markers in detecting myocardial ischemic damage in adults. Perinatal asphyxia is associated with cardiac dysfunction.

Objectives: To evaluate serum concentrations of cTnI in asphyxiated neonates and to investigate whether cTnI is correlated with the traditional markers of asphyxia.

Methods: Blood samples were collected from 13 asphyxiated neonates (umbilical artery pH<7.18 and either a 1-min Apgar score<4 or a 5-min Apgar score<7) and 39 controls. Data on gestation, birth weight, sex, Apgar scores, mode of delivery, umbilical pH, creatinine, serum activity of aspartate and alanine aminotransferase, and QTc interval were investigated.

Results: Median (range) cTnI concentrations were significantly higher in asphyxiated neonates with respect to healthy infants: 0.36 microg/l (0.05-11) versus 0.04 microg/l (0.04-0.06); p<0.01. In asphyxiated babies, no statistically significant correlations were found between concentrations of cTnI and the other markers of asphyxia.

Conclusions: In asphyxiated neonates, cTnI concentrations are higher with respect to healthy infants, suggesting the presence of myocardial damage in this group of high-risk patients. cTnI does not correlate with the traditional markers of asphyxia.
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http://dx.doi.org/10.1159/000089795DOI Listing
May 2006

NT-proBNP in the differential diagnosis of acute dyspnea in the emergency department.

Clin Biochem 2005 Nov 6;38(11):1041-4. Epub 2005 Sep 6.

Department of Laboratory Medicine, University-Hospital, Padova, Italy.

Objectives: The purpose of this study was to verify the usefulness of NT-proBNP in the differential diagnosis of dyspnea in a population of patients presenting in the ER with breathlessness.

Design And Methods: In samples from 122 patients presenting in the ER with acute-severe dyspnea and from 25 subjects enrolled as a "comparison group" (NORM), NT-proBNP levels were measured. Patients have been classified on the basis of discharge diagnosis: pulmonary disease (PD, n = 23), pulmonary concomitant to cardiac disease (MIXED, n = 17), pulmonary embolism (EMB, n = 8), cardiac disease (CARD, n = 56), acute myocardial infarction (AMI, n = 11) and other disease (OTHER, n = 7).

Results: A significant difference in NT-proBNP values (P
Conclusions: NT-proBNP measurement represents a useful biochemical tool helping the ER physician in the rapid and reliable recognition of cardiac involvement in patients presenting in the ER with acute-severe dyspnea.
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http://dx.doi.org/10.1016/j.clinbiochem.2005.07.010DOI Listing
November 2005

Cord blood cardiac troponin T and troponin I levels in multiple-gestation neonates.

Biol Neonate 2004 21;85(4):269-72. Epub 2004 Jan 21.

Pediatric Department, University of Padova Medical School, Padova, Italy.

The increased mortality and morbidity rates in multiple-gestation neonates are not completely understood. Troponin measurements have a role in situations where the evaluation of the cardiac damage is difficult, such as in cases of unexplained intrauterine fetal growth restriction or death. These conditions, along with perinatal hypoxic risk and in utero ischemic damage, are frequently found in multiple gestations. In this context, a myocardial damage could be expected more frequently in multiple than in singleton births. We hypothesized that cord blood cardiac troponin T and troponin I, markers of myocardial damage, could be different between singleton and multiple pregnancies and, among twins, between the first- and the second-born twin. Troponins T and I and creatine kinase MB concentrations were not increased in twins at birth and were not different between the first- and the second-born twin. These data suggest that myocardial damage, evaluated by cardiac troponin T, troponin I, and creatine kinase MB measurements, does not seem to be a relevant problem in multiple-gestation neonates.
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http://dx.doi.org/10.1159/000076365DOI Listing
December 2004