Heart failure is the most frequent cardiac complication of chronic kidney disease (CKD). Biomarkers help identify high-risk patients. Natriuretic peptides (BNP and NT-proBNP) are largely used for monitoring patients with cardiac failure but are highly dependent on glomerular filtration rate (GFR). Soluble suppression of tumorigenicity 2 (sST2) biomarker is well identified in risk stratification of cardiovascular (CV) events in heart failure. Furthermore, sST2 is included in a bioclinical score to stratify mortality risk. The aims of this study were to evaluate (i) the interest of circulating sST2 level in heart dysfunction and (ii) the bioclinical score (Barcelona Bio-Heart Failure risk calculator) to predict the risk of composite outcome (major adverse coronary events) and mortality in the CKD population. A retrospective study was carried out on 218 CKD patients enrolled from 2004 to 2015 at Montpellier University Hospital. sST2 was measured by ELISA (Presage ST2® kit). GFR was estimated by the CKD-EPI equation (eGFR). Indices of cardiac parameters were performed by cardiac echography. No patient had reduced ejection fraction. 112 patients had left ventricular hypertrophy, and 184 presented cardiac dysfunction, with structural, functional abnormalities or both. sST2 was independent of age and eGFR (ρ=0.05, p=0.44, and ρ=−0.07, p=0.3, respectively). Regarding echocardiogram data, sST2 was correlated with left ventricular mass index (ρ=0.16, p=0.02), left atrial diameter (ρ=0.14, p=0.04), and volume index (ρ=0.13, p=0.05). sST2 alone did not change risk prediction of death and/or CV events compared to natriuretic peptides. Included in the Barcelona Bio-Heart Failure (BCN Bio-HF) score, sST2 added value and better stratified the risk of CV events and/or death in CKD patients (p<0.0001). To conclude, sST2 was associated with cardiac remodeling independently of eGFR, unlike other cardiac biomarkers. Added to the BCN Bio-HF score, the risk stratification of death and/or CV events in nondialyzed CKD patients was highly improved.

A newly developed fully automated Lumipulse G AMH method (Fujirebio Diagnostics) was recently introduced in clinical laboratories for quantitative determination of anti-Müllerian hormone (AMH) level in human serum or plasma. AMH has emerged as value-added biomarker in the assessment of ovarian reserve, in diagnosis of granulosa cells cancer and in the investigation of gonadal disorders. We compared Lumipulse G AMH assay performances with other methods largely applied for AMH measurements. The Lumipulse G AMH method based on two-step sandwich chemiluminescence enzyme immunoassay was assessed on Lumipulse G600II analyzer. The evaluation study included imprecisions, sensitivity and linearity whereas a comparison study was performed on a heterogeneous population of 114 patients by using the Elecsys AMH Plus assay on COBAS 8000 e602 module (Roche Diagnostics). Lumipulse G AMH system showed good repeatability (within-run imprecision) with CV values below 1% (0.5% and 0.9% for high and low serum pools). Similarly within-laboratory imprecision was assessed with CV values of 2.5% and 1.6% for high and low level controls respectively. A linearity regression formula of 1.0119x-0.067 with a coefficient of determination (r2) equal to 0.999 was obtained in a range from 0.044 to 22.42 ​ng/ml. Passing-Bablok regression analysis was performed for assay comparability of AMH measurements. Results were closely correlated (correlation coefficient ​= ​0.997) with a regression equation (y ​= ​1.230x-0.025) showing a positive slope. Also, Bland-Altman analysis confirmed a good agreement between Lumipulse G AMH and Roche Elecsys AMH Plus assays with a bias of 17.76% in a large measurement range. The performance of Lumipulse G AMH system was highly comparable with that of Roche Elecsys AMH Plus assay although approximately 10% higher values of AMH levels were observed for Lumipulse AMH system at all range of concentrations. Nevertheless the Lumipulse G system seems to be largely suitable for quantitative determination of AMH level in small-scale laboratory because of the reduced size and the use of single cartridge per test assuring flexibility and easy handling.

Objectives: Aldosterone and renin determinations play an important role in the etiological diagnosis of secondary hypertension. The analytical performances of new aldosterone and renin immunoassays on the Lumipulse G600II^® system (Fujierbio) were investigated and compared with those of the iSYS^® system (IDS) on patients concerned by medical investigations in a context of suspected or proven Primary aldosteronism. Methods: By using the Lumipulse^® G Aldosterone and Renin assays we performed imprecision study, linearity and method comparison (n=107). Accuracy of this new renin assay was tested using the International Standard (WHO IS 68/356). We also assessed the equivalence of the different samples types (n=29). Results: The imprecision evaluation showed all CVs <3% and <6% for Lumipulse^® G Aldosterone and Renin assays respectively. The linearity was excellent over the clinical range and the comparison with the iSYS^® assays (n=79) showed a strong correlation (R²=1) despite a slight tendency to underestimation (bias of −17.53 pg/mL or 48.56 pmol/L for aldosterone and −15.395 pg/mL for renin). Moreover, the contingency studies based on diagnostic criteria showed that Lumipulse^® G results lead to the same clinical diagnosis that iSYS^® results. A clear correlation was obtained between EDTA and heparin plasma as well as with the serum for all range of measures. Conclusions: The Lumipulse^® G Aldosterone and Renin assays present performances compatible with a routine use in medical laboratories. The precise quantification in the low range can be of interest in some clinical contexts especially standing/laying tests. However, the standardisation against the WHO International Standard Renin would be advisable.

Objectives Human growth hormone (hGH) provocation test is an essential tool to assess growth hormone deficiency (GHD) in children and young adults. It is important to have a robust method to determine the hGH peak of stimulation. This work aimed to compare three common automated immunoassays for hGH quantification and to ascertain whether there are still result-related differences which can impact clinical decision. Methods We analyzed the GH provocation test for 39 young subjects from pediatric department of Montpellier hospital, admitted for suspicion of growth hormone deficiency. The full range of measurements as well as the peak level of serum GH were compared using three automated immunoassays on three different immunoanalyzers: IDS-hGH on iSYS, LIAISON-hGH on Liaison XL and Elecsys ROCHE-hGH, on COBAS 8000. Results A good correlation was obtained between methods for all measurements (r²>0.99) by using Passing–Bablok regression analysis. Bland–Altman analysis showed the best agreement between IDS-hGH and LIAISON-hGH systems (bias=−14.5%) compared to Elecsys ROCHE-hGH (bias=28.3%). When considering stratification of the study population and a unique cutoff, there were some discrepancies in interpretation of the results especially concerning the more recent Elecsys ROCHE-hGH assay. Nevertheless, when the adequate cutoff for each method was taken into account results were well correlated for all systems. Conclusions A cutoff for Elecsys Roche-hGH method was established to better explain the results. Clinician must be aware of the use of assay-specific cutoff to correctly integrate the results of GH tests in the GHD diagnosis.