Cardiomuscular Biomarkers in the Diagnosis and Prognostication of Immune Checkpoint Inhibitor Myocarditis.

BACKGROUND: Immune checkpoint inhibitors (ICIs) are approved for multiple cancers but can result in ICI-associated myocarditis, an infrequent but life-threatening condition. Elevations in cardiac biomarkers, specifically troponin-I (cTnI), troponin-T (cTnT), and creatine kinase (CK), are used for diagnosis. However, the association between temporal elevations of these biomarkers with disease trajectory and outcomes has not been established. METHODS: We analyzed the diagnostic accuracy and prognostic performances of cTnI, cTnT, and CK in patients with ICI myocarditis (n=60) through 1-year follow-up in 2 cardio-oncology units (APHP Sorbonne, Paris, France and Heidelberg, Germany). A total of 1751 (1 cTnT assay type), 920 (4 cTnI assay types), and 1191 CK sampling time points were available. Major adverse cardiomyotoxic events (MACE) were defined as heart failure, ventricular arrhythmia, atrioventricular or sinus block requiring pacemaker, respiratory muscle failure requiring mechanical ventilation, and sudden cardiac death. Diagnostic performance of cTnI and cTnT was also assessed in an international ICI myocarditis registry. RESULTS: Within 72 hours of admission, cTnT, cTnI, and CK were increased compared with upper reference limits (URLs) in 56 of 57 (98%), 37 of 42 ([88%] P=0.03 versus cTnT), and 43 of 57 ([75%] P<0.001 versus cTnT), respectively. This increased rate of positivity for cTnT (93%) versus cTnI ([64%] P<0.001) on admission was confirmed in 87 independent cases from an international registry. In the Franco-German cohort, 24 of 60 (40%) patients developed ≥1 MACE (total, 52; median time to first MACE, 5 [interquartile range, 2-16] days). The highest value of cTnT:URL within the first 72 hours of admission performed best in terms of association with MACE within 90 days (area under the curve, 0.84) than CK:URL (area under the curve, 0.70). A cTnT:URL ≥32 within 72 hours of admission was the best cut-off associated with MACE within 90 days (hazard ratio, 11.1 [95% CI, 3.2-38.0]; P<0.001), after adjustment for age and sex. cTnT was increased in all patients within 72 hours of the first MACE (23 of 23 [100%]), whereas cTnI and CK values were less than the URL in 2 of 19 (11%) and 6 of 22 (27%) of patients (P<0.001), respectively. CONCLUSIONS: cTnT is associated with MACE and is sensitive for diagnosis and surveillance in patients with ICI myocarditis. A cTnT:URL ratio <32 within 72 hours of diagnosis is associated with a subgroup at low risk for MACE. Potential differences in diagnostic and prognostic performances between cTnT and cTnI as a function of the assays used deserve further evaluation in ICI myocarditis.

Cell-Cycle Arrest Biomarkers: Usefulness for Cardiac Surgery-Related Acute Kidney Injury in Neonates and Infants.

OBJECTIVES: Cell cycle arrest urine biomarkers have recently been shown to be early indicators of acute kidney injury in various clinical settings in critically ill adults and children. The product of tissue inhibitor metalloproteinase -1 and insulin-like growth factor binding protein-7 concentrations/1,000 (TIMP-1) × (IGFBP-7) provides stratification of acute kidney injury-risk in adults with critical illness. The present study explores the predictive accuracy of (TIMP-1) × (IGFBP-7) measured early after cardiopulmonary bypass for cardiac surgery-related acute kidney injury in neonates and infants, a population in whom such data are not yet available. DESIGN: Prospective, observational. SETTING: A tertiary referral pediatric cardiac ICU. PATIENTS: Fifty-seven neonates and 110 infants undergoing surgery with cardiopulmonary bypass. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: (TIMP-1) × (IGFBP-7) was measured on the NephroCheck (Astute Medical, San Diego, CA) platform preoperatively, less than 1 hour of cardiopulmonary bypass and 1-3 hours of cardiopulmonary bypass. The incidence of postoperative acute kidney injury, dialysis, and/or death were compared among quintiles of postoperative (TIMP-1) × (IGFBP-7). Multivariable regression was used to assess the added predictive value for renal events of (TIMP-1) × (IGFBP-7) over clinical models. Basal (TIMP-1) × (IGFBP-7) increased with age at surgery (regression coefficient = 0.004 ± 0.001; p = 0.005). (TIMP-1) × (IGFBP-7) increased after cardiopulmonary bypass. Neonates had lower postoperative (TIMP-1) × (IGFBP-7) compared with older infants, despite undergoing longer surgeries and experiencing a higher incidence of postoperative renal events. (TIMP-1) × (IGFBP-7) was not associated with acute kidney injury, dialysis, and/or death and was not a predictor of the aforementioned events when added to a clinical acute kidney injury model including age, duration of cardiopulmonary bypass, and mechanical ventilation prior to surgery. CONCLUSIONS: These findings question the usefulness of (TIMP-1) × (IGFBP-7) for the prediction of cardiac surgery-related acute kidney injury in neonates and infants when measured within 3 hours of cardiopulmonary bypass.

Multicenter Evaluation of Cystatin C Measurement after Assay Standardization.

BACKGROUND: Since 2010, a certified reference material ERM-DA471/IFCC has been available for cystatin C (CysC). This study aimed to assess the sources of uncertainty in results for clinical samples measured using standardized assays. METHODS: This evaluation was performed in 2015 and involved 7 clinical laboratories located in France and Belgium. CysC was measured in a panel of 4 serum pools using 8 automated assays and a candidate isotope dilution mass spectrometry reference measurement procedure. Sources of uncertainty (imprecision and bias) were evaluated to calculate the relative expanded combined uncertainty for each CysC assay. Uncertainty was judged against the performance specifications derived from the biological variation model. RESULTS: Only Siemens reagents on the Siemens systems and, to a lesser extent, DiaSys reagents on the Cobas system, provided results that met the minimum performance criterion calculated according to the intraindividual and interindividual biological variations. Although the imprecision was acceptable for almost all assays, an increase in the bias with concentration was observed for Gentian reagents, and unacceptably high biases were observed for Abbott and Roche reagents on their own systems. CONCLUSIONS: This comprehensive picture of the market situation since the release of ERM-DA471/IFCC shows that bias remains the major component of the combined uncertainty because of possible problems associated with the implementation of traceability. Although some manufacturers have clearly improved their calibration protocols relative to ERM-DA471, most of them failed to meet the criteria for acceptable CysC measurements.

[Immuno-analytical characteristics of PSA and derived biomarkers (total PSA, free PSA, p2PSA)]. / Caractéristiques immuno-analytiques du PSA et des biomarqueurs dérivés (PSA total, PSA libre et P2ProPSA).

Prostate-specific antigen (PSA) is the recommended tumor marker for individual screening and follow-up of prostate cancer. This paper reviews main structural and physiological data about prostate specific antigen isoforms: total PSA, free PSA, [-2]proPSA (also named p2PSA). It describes the pre-, per- and post-analytical conditions for these different parameters. It presents the interpretation of results and derived calculated indices (free/total PSA ratio, Prostate Health Index or PHI) for the management of prostate cancer (initial diagnosis and follow-up).

Cell and cytokine analyses from bronchoalveolar lavage in non-critical COVID-19 pneumonia.

Cell and cytokine analyses from bronchoalveolar lavage (BAL) in non-critically ill patients with COVID-19 pneumonia are poorly described. This study focused on patients hospitalized in the non-intensive care unit for either suspected COVID-19 pneumonia or persistent respiratory symptoms following proven COVID-19 pneumonia. Overall, 54 patients who underwent BAL between April 2020 and February 2021 for suspected or follow-up of proven COVID-19 pneumonia were included. Based on SARS-CoV-2 polymerase chain reaction test results and clinical follow-up, three pulmonary disease groups were defined: non-COVID-19 (n = 20), acute COVID-19 (n = 13), and post-COVID-19 (n = 24) pneumonia patients. Cytological and cytokine analyses were performed on BAL fluid (IL-1ß, IL-6, IL-8, IL-10, TNF-α, IFN-γ, HGF, and TGF-ß), with investigators blinded to the patient groups. Lymphocytic alveolitis with plasmocytes was observed in acute COVID-19 pneumonia, returning to normal post-COVID-19. The highest cytokine levels were observed in COVID-19 patients, with significantly increased IFN-γ, IL-10, and HGF levels compared to non-COVID-19 patients, while significantly decreased IL-6, IL-8, IL-10, IFN-γ, TNF-α, and HGF levels were noted in post-COVID-19 patients. In COVID-19 patients, correlations between IL-10, TNF-α and IFN-γ concentrations were found. Lymphocytic alveolitis with plasmacytosis was found in non-critical COVID-19 pneumonia This alveolitis is associated with the presence of IL-6, IL-8, IL-10, TNF-α, IFN-γ and HGF. Alveolitis and cytokines levels decreased in post-COVID-19 pneumonia.

Prognostic value of serum Krebs von den Lungen-6 (KL-6) levels in COVID-19 pneumonia.

BACKGROUND AND OBJECTIVES: Krebs von den Lungen-6 (KL-6), expressed by damaged type II pneumocytes, is useful in the diagnosis and severity assessment of many diffuse interstitial lung diseases. The objective of our study was to determine the prognostic value of the initial KL-6 plasma level in COVID-19 pneumonia. METHODS: All patients hospitalized for a suspected COVID-19 pneumonia between March and May 2020 in our Chest department of a French university hospital were included. KL-6 serum concentrations were measured within 72 h of diagnostic suspicion by chemiluminescence enzyme immunoassay Survival analysis was performed using a Cox regression and modeled by a Kaplan-Meier curve. RESULTS: Sixty-six COVID-19 patients (average age = 64 ± 14 years, 71.2 % males) with KL-6 serum measurement were included. Median KL-6 serum concentration was 409 ± 312 U/mL. KL-6 was significantly higher in men (p = 0.003), elders (p = 0.0001) and in patients with greater Charlson's score (p = 0.002). Higher KL-6 concentration was significantly associated with in-hospital mortality (HR: 8.66; 95 % CI:1.1-69.2, p = 0.014), radiological extension of lesions on chest CT scan (p = 0.004) and higher WHO severity score (p = 0.042), but not with admission in intensive care unit. In 9 (14 %) non-surviving COVID-19 patients, KL-6 serum concentration increased whereas it remained stable or decreased in survivors. At 3 months follow-up (n = 48), DLCO was negatively correlated with the initial KL-6 value (r = 0.47, p = 0.001), while FVC, FEV1 and MRC score were not. CONCLUSION: Initial KL-6 serum concentration is significantly associated with in-hospital mortality, unfavorable outcome, and persistent impairment of DLCO at 3 months. Initial KL-6 plasma determination appears as a prognostic biomarker in COVID-19 pneumonia.

Pulmonary hypertension without heart failure causes cardiorenal syndrome in a porcine model.

Cardiorenal syndromes type 1 and 2 are complex disorders in which cardiac dysfunction leads to kidney dysfunction. However, the mechanisms remain incompletely explained, during pulmonary hypertension in particular. The objective of this study is to develop an original preclinical model of cardiorenal syndrome secondary to a pulmonary hypertension in piglets. Twelve 2-month-old Large White piglets were randomized in two groups: (1) induction of pulmonary hypertension by ligation of the left pulmonary artery and iterative embolizations of the right lower pulmonary artery, or (2) Sham interventions. We evaluated the cardiac function using right heart catheterization, echocardiography and measurement of biochemistry markers). Kidney was characterized using laboratory blood and urine tests, histological evaluation, immunostainings for renal damage and repair, and a longitudinal weekly assessment of the glomerular filtration rate using creatinine-based estimation and intravenous injection of an exogenous tracer on one piglet. At the end of the protocol (6 weeks), the mean pulmonary artery pressure (32 ± 10 vs. 13 ± 2 mmHg; p = 0.001), pulmonary vascular resistance (9.3 ± 4.7 vs. 2.5 ± 0.4 WU; p = 0.004) and central venous pressure were significantly higher in the pulmonary hypertension group while the cardiac index was not different. Piglets with pulmonary hypertension had higher troponin I. We found significant tubular damage and an increase in albuminuria in the pulmonary hypertension group and negative correlation between pulmonary hypertension and renal function. We report here the first porcine model of cardiorenal syndrome secondary to pulmonary hypertension.

How useful is an oral calcium load test for diagnosing recurrent calcium stone formers?

Hypercalciuria is the main risk factor for recurrent calcium urolithiasis. The goal of our study is to determinate how useful an oral calcium load test is for stone formers to classify different forms of hypercalciuria in pathogenetic categories defined as renal or absorptive according to the current knowledge. Between June 2013 and February 2016, a prospective study was carried out on 117 documented recurrent hypercalciuric stone formers undergoing an oral calcium load test modified from the original description by Pak. After 2 days of calcium-restricted diet, urine and blood were analyzed at baseline and 120 min after receiving orally 1 g of calcium. Total and ionized calcium, parathyroid hormone from serum and urine calcium and creatinine were assessed in order to divide patients in three groups as previously described: resorptive, absorptive, and renal hypercalciuria. This allowed the identification of 19, 39, 34 and 33 patients with normocalcemic primary hyperparathyroidism (NPHPT), renal hypercalciuria aka renal calcium leak (RCL), absorptive hypercalciuria (AH) and unidentified cause, respectively. Patients with NPHPT (who required parathyroidectomy) experienced a lower PTH decrease (41.41 ± 12.82 vs. 54.06 ± 13.84% p < 0.01), higher beta-crosslaps, as well as lower TmP/GFR and distal third radius bone mineral density. RCL resulted in increased fasting urine calcium-to-creatinine ratio (Uca/Cr), i.e., > 0.37 mmol/mmol), without hyperparathyroidism. AH was diagnosed by the presence of ΔUCa/Cr > 0.60 mmol/mmol between baseline and 120 min without any other anomaly. For all remaining patients, results were inconclusive due to the lack of sufficient increase in serum calcium or because the cause of lithogenesis could not be clearly identified. The oral calcium load test is useful in nearly 80% of patients by identifying the different forms of hypercalciuria causing urolithiasis and by guiding treatment, including parathyroid surgery.

How the diagnosis and the management of genetic renal phosphate leak impact the life of kidney stone formers?

Genetic renal phosphate leak is one of the rare disorders in recurrent stone formers with absorptive hypercalciuria. Diagnosis and appropriate management may change the life of patients. To provide answers on how and when to make the diagnosis of genetic renal phosphate leak and how medical management prevents the recurrences and changes patients' life, we conducted a retrospective study including nine patients with recurrent nephrolithiasis and a confirmed genetic mutation of a phosphate transporter between 2008 and 2019 in our multidisciplinary center at the Pitié Salpetriere Hospital, Paris, France. We compared the number and the annual rate of urological intervention before and after the diagnosis and management using the Wilcoxon test. A qualitative survey was done to evaluate the quality of life of patients. A total of 9 patients were included in this study. Patient baseline characteristics and elements supporting the diagnosis are described. We showed an effective decrease in urological intervention number (p = 0.0078) and annual rate (p = 0.0117) after the diagnosis and the appropriate management, and an improvement in the patients' quality of life. The diagnosis and the appropriate management of genetic renal phosphate leak disorder improve the quality of life by preventing stone recurrence and decreasing the number of surgical intervention.

[Recommendations for the selection and alignment techniques for the determination of creatinine]. / Recommandations pour le choix et l'harmonisation des techniques de dosage de la créatinine.

In 2010, a working group from the French Society of Clinical Chemistry (Société française de biologie clinique - SFBC) and the French Society of Nephrologie (SN) make a proposal to up-date the guidelines for measuring plasma creatinine.

Urinary strips for protein assays: easy to do but difficult to interpret!

Urine samples can be readily obtained from patients in everyday clinical practice. Therefore, the availability of urine allows physicians to obtain relevant clinical information in a timely manner. Since the measurement of urinary protein levels is essential in diagnosing and treating a host of diseases, the potential detection of urinary proteins by urinary strips in an easy, quick, and cheap way is very attractive. However, to ensure optimal use of urinary strips, one needs to be aware of their characteristics and their limitations. In this review, we discuss the characteristics of the urinary strips available for testing urinary protein levels and for detecting urinary albumin. We then consider their analytical performances in their most widely used clinical applications (e.g., in pregnancy, chronic kidney disease, diabetes, and screening of the general population).

[POCT-management during the first wave of Covid-19 in France. Results of a national survey leaded by the SFBC-POCT Working Group]. / Gestion de la biologie délocalisée lors de la première vague de Covid-19 en France. Résultats de l'enquête nationale menée par le groupe de travail des EBMD de la SFBC.

During the first wave of Covid-19 in France, in spring 2020, healthcare institution's laboratory had to adapt itself quickly to the growing demand for emergency biology, in particular by reorganizing their POCT analyzers: redeployment of analyzers and/or new installations. In order to analyze this management, a subgroup of 15 hospital biologists from the SFBC Working Group "Biochemical markers of Covid-19" sent, in fall 2020, an on-line survey to French hospital laboratories using POCT. Answers analysis (n = 86) shows a territorial disparity related to the severity of the first wave: increased activity essentially in red zones, management of unexpected situations, training of additional nursing staff for 40 % of the laboratories... The survey also showed simplification of aspects related to accreditation those periods of health crisis. An additional survey, carried out in the spring of 2021, showed good overall satisfaction of the healthcare services (n = 139) concerning the services provided by biology in the POCT sector. Because of their great adaptation capacity, the laboratories and their POCT-teams have played a key role in the management of the first wave of Covid-19 in France. However, the success of these organizations requires an essential collaboration between laboratories and healthcare services. The results of this survey are fundamental in the context of the prolongation of the pandemia throughout the world with a POCT sector appearing to be growing.

[Creatinine: past and present]. / La créatinine: d'hier à aujourd'hui.

Serum creatinine is certainly one of the most prescribed biological parameters. In this review article, we remind some historical data regarding creatinine. Different methodologies to measure creatinine in blood and urine are deeply described. We also discuss the physiological reason for its use as a glomerular filtration rate marker. However, analytical and physiological limitations are described and discussed. Creatinine clearance usefulness is finally largely discussed.

Chronic Kidney Disease in Adolescents after Surgery for Congenital Heart Disease.

BACKGROUND: The onset of chronic kidney disease (CKD) is an important prognostic factor in young adults with congenital heart disease (CHD). Although it is likely that CKD is manifest early in CHD patients, the prevalence among adolescents is still unknown. The National Kidney Foundation's Kidney Disease Improving Global Outcomes guidelines 2012 recommend new equations for the estimated glomerular filtration rate (eGFR) and highlight the importance of albuminuria for CKD screening. The objective of the present study was to estimate the prevalence of CKD in CHD adolescents. METHODS: This observational cross-sectional study included 115 patients aged 10-18 years attending the cardiologic outpatient clinic at our institution as a follow-up after cardiac surgery in infancy related to various CHDs. CKD assessment used the CKD criteria 2012, including eGFR equations based on serum creatinine and cystatin C, and measurement of albuminuria. RESULTS: No patient had an eGFR <60 mL min-1 1.73 m-2. However, 28.7% of all patients (95% CI 20.7-37.9) had eGFRbetween 60 and 89 mL min-1 1.73 m-2 when estimated by the bedside Schwartz creatinine-based equation,and 17.4% (95% CI 11.2-24.1) had eGFRbetween 60 and 89 mL min-1 1.73 m-2 when estimated by the Zappitelli equation, combining creatinine and cystatin C. Of all patients, 20.0% (95% CI 12.1-26.7) had orthostatic proteinuria, and none had persistent albuminuria. CONCLUSIONS: There was no evidence of CKD in the present population aged 10-18 years. The significance of an eGFR between 60 and 90 mL min-1 1.73 m-2 is not concordant for this age range and requires further investigations.

[Examples of accreditation of serum and urinary proteins electrophoresis]. / Expériences d'accréditation des électrophorèses sériques et urinaires.

Serum proteins and urinary proteins electrophoresis are useful biological tests. They are often prescribed for the screening of monoclonal gammopathys and also during follow-up for treatment response. This test can be accredited according to standard NF ISO 15189 since laboratories use analysers and adapted reagents, but there are numerous protocols for the method validation. This paper present the results of a survey proposed in 2019 to biologists by CNBH and SFBC. The aim of this survey is to give biologists a choice among several protocols that have been positively evaluated by COFRAC.

[SFBC working group "Biochemical markers of COVID-19"]. / Groupe de travail SFBC « Marqueurs biochimiques de COVID-19 ¼.

The SARS-CoV-2 virus is responsible for an epidemic disease called COVID-19, which was initially evidenced in Wuhan, China, and spread very rapidly in China and around the world. In France, the first isolated case seems now to be reported in December 2019, stage 3 of the COVID-19 epidemic was triggered on March 14th, the start of the planned containment exit from May 11th. Healthcare services have faced a large influx of patients who may be beyond their capacity to receive and care, particularly in the Large-East and Ile-de-France regions. Some patients show an evolution of the disease never observed before with other coronaviruses and develop in a few days a very important inflammatory reaction, which can lead to death of patients. A working group of the French Society of Clinical Biology (SFBC) was set up with the objective of providing updated information on the current status of the biological prescriptions (focusing on biochemistry ones) and their evolution during the epidemic, and of analyzing the biological parameters associated with comorbidities and patient evolution in order to link biological results with medical events. The expanded working group covers all sectors of medical biology in France and extends to the French-speaking world: hospital sectors (CHU and CH, Army Training Hospitals) and the private sector opening a field of view on the biological situation in establishments for dependent elderly, social establishments and clinical medical institutions. The purpose of this article is the presentation of this working group and its immediate and future actions.

[Management of a global health crisis: first COVID-19 disease feedback from Overseas and French-speaking countries medical biologists]. / Gestion d'une crise sanitaire mondiale : premiers retours d'expérience de biologistes médicaux d'Outre-mer et de francophonie face au COVID-19.

The French society of clinical biology "Biochemical markers of COVID-19" has set up a working group with the primary aim of reviewing, analyzing and monitoring the evolution of biological prescriptions according to the patient's care path and to look for markers of progression and severity of the disease. This study covers all public and private sectors of medical biology located in metropolitan and overseas France and also extends to the French-speaking world. This article presents the testimonies and data obtained for the "Overseas and French-speaking countries" sub-working group made up of 45 volunteer correspondents, located in 20 regions of the world. In view of the delayed spread of the SARS-CoV-2 virus, the overseas regions and the French-speaking regions have benefited from feedback from the first territories confronted with COVID-19. Thus, the entry of the virus or its spread in epidemic form could be avoided, thanks to the rapid closure of borders. The overseas territories depend very strongly on air and/or sea links with the metropolis or with the neighboring continent. The isolation of these countries is responsible for reagent supply difficulties and has necessitated emergency orders and the establishment of stocks lasting several months, in order to avoid shortages and maintain adequate patient care. In addition, in countries located in tropical or intertropical zones, the diagnosis of COVID-19 is complicated by the presence of various zoonoses (dengue, Zika, malaria, leptospirosis, etc.).

Proteinuria prescription in 2019.

Today, medical prescriptions of proteinuria or albuminuria, which are depending on medical status of patients, still depend on doctors. Indeed, according to their medical specialty or to the recommendations they are following, they could prescribe either proteinuria or albuminuria. The consequences are practical for laboratories and economical for patients and doctors. This article resumes different situations, which result in an erroneous interpretation of medical prescriptions.