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Background Epidemiological studies in humans show increased concentrations of copeptin, a surrogate marker of arginine vasopressin (AVP), to be associated with increased risk for type 2 diabetes. Objectives To examine the acute and independent effect of osmotically stimulated AVP, measured via the surrogate marker copeptin, on glucose regulation in healthy adults. Methods Sixty subjects (30 females) participated in this crossover design study. On 2 trial days, separated by ≥7 d (males) or 1 menstrual cycle (females), subjects were infused for 120 min with either 0.9% NaCl [isotonic (ISO)] or 3.0% NaCl [hypertonic (HYPER)]. Postinfusion, a 240-min oral-glucose-tolerance test (OGTT; 75 g) was administered. Results During HYPER, plasma osmolality and copeptin increased (P  < 0.05) and remained elevated during the entire 6-h protocol, whereas renin-angiotensin-aldosterone system hormones were within the lower normal physiological range at the beginning of the protocol and declined following infusion. Fasting plasma glucose did not differ between trials (P  > 0.05) at baseline and during the 120 min of infusion. During the OGTT the incremental AUC for glucose from postinfusion baseline (positive integer) was greater during HYPER (401.5 ± 190.5 mmol/L·min) compared with the ISO trial (354.0 ± 205.8 mmol/L·min; P <  0.05). The positive integer of the AUC for insulin during OGTT did not differ between trials (HYPER 55,850 ± 36,488 pmol/L·min compared with ISO 57,205 ± 31,119 pmol/L·min). Baseline values of serum glucagon were not different between the 2 trials; however, the AUC of glucagon during the OGTT was also significantly greater in HYPER (19,303 ± 3939 ng/L·min) compared with the ISO trial (18,600 ± 3755 ng/L·min; P  < 0.05). Conclusions The present data indicate that acute osmotic stimulation of copeptin induced greater hyperglycemic responses during the oral glucose challenge, possibly due to greater glucagon concentrations. This study was registered at clinicaltrials.gov as NCT02761434. [ABSTRACT FROM AUTHOR]

During the past decades the healthcare systems have rapidly changed and today hospital care is primarily advocated for critical patients and acute treatments, for which laboratory test results are crucial and need to be always reported in predictably short turnaround time (TAT). Laboratories in the hospital setting can face this challenge by changing their organization from a compartmentalized laboratory department toward a decision making-based laboratory department. This requires the implementation of a core laboratory, that exploits total laboratory automation (TLA) using technological innovation in analytical platforms, track systems and information technology, including middleware, and a number of satellite specialized laboratory sections cooperating with care teams for specific medical conditions. In this laboratory department model, the short TAT for all first-line tests performed by TLA in the core laboratory represents the key paradigm, where no more stat testing is required because all samples are handled in real-time and (auto)validated results dispatched in a time that fulfills clinical needs. To optimally reach this goal, laboratories should be actively involved in managing all the steps covering the total examination process, speeding up also extra-laboratory phases, such sample delivery. Furthermore, to warrant effectiveness and not only efficiency, all the processes, e.g. specimen integrity check, should be managed by middleware through a predefined set of rules defined in light of the clinical governance. [ABSTRACT FROM AUTHOR]

Objective: To compare the effectiveness of a single-layered polyethylene survival bag (P), a single-layered polyethylene survival bag with a hot drink (P+HD), a multi-layered metalized plastic sheeting survival bag (MPS: Blizzard Survival), and a multi-layered MPS survival bag with 4 large chemical heat pads (MPS+HP: Blizzard Heat) to treat cold casualties.Methods: Portable cold casualty treatment methods were compared by examining core and skin temperature, metabolic heat production, and thermal comfort during a 3-hour, 0°C cold air exposure in 7 shivering, near-hypothermic men (35.4°C). The hot drink (70°C, ~400 ml, ~28 kJ) was consumed at 0, 1, and 2 hours during the cold air exposure.Results: During the cold air exposure, core rewarming and thermal comfort were similar on all trials (P = .45 and P = .36, respectively). However, skin temperature was higher (10%-13%; P < .001; large effect sizes d > 2.7) and metabolic heat production lower (15%-39%; P < .05; large effect sizes d > .9) on MPS and MPS+HP than P and P+HD. The addition of heat pads further lowered metabolic heat production by 15% (MPS+HP vs MPS; P = .05; large effect size d = .9). The addition of the hot drink to polyethylene survival bag did not increase skin temperature or lower metabolic heat production.Conclusions: Near-hypothermic cold casualties are rewarmed with less peripheral cold stress and shivering thermogenesis using a multi-layered MPS survival bag compared with a polyethylene survival bag. Prehospital rewarming is further aided by large chemical heat pads but not by hot drinks. [ABSTRACT FROM AUTHOR]

Background: The identification of beverages that promote longer-term fluid retention and maintenance of fluid balance is of real clinical and practical benefit in situations in which free access to fluids is limited or when frequent breaks for urination are not desirable. The postingestion diuretic response is likely to be influenced by several beverage characteristics, including the volume ingested, energy density, electrolyte content, and the presence of diuretic agents. Objective: This study investigated the effects of 13 different commonly consumed drinks on urine output and fluid balance when ingested in a euhydrated state, with a view to establishing a beverage hydration index (BHI), i.e., the volume of urine produced after drinking expressed relative to a standard treatment (still water) for each beverage. Design: Each subject (n = 72, euhydrated and fasted male subjects) ingested 1 L still water or 1 of 3 other commercially available beverages over a period of 30 min. Urine output was then collected for the subsequent 4 h. The BHI was corrected for the water content of drinks and was calculated as the amount of water retained at 2 h after ingestion relative to that observed after the ingestion of still water. Results: Total urine masses (mean ± SD) over 4 h were smaller than the still-water control (1337 ± 330 g) after an oral rehydration solution (ORS) (1038 ± 333 g, P < 0.001), full-fat milk (1052 ± 267 g, P < 0.001), and skimmed milk (1049 ± 334 g, P < 0.001). Cumulative urine output at 4 h after ingestion of cola, diet cola, hot tea, iced tea, coffee, lager, orange juice, sparkling water, and a sports drink were not different from the response to water ingestion. The mean BHI at 2 h was 1.54 ± 0.74 for the ORS, 1.50 ± 0.58 for full-fat milk, and 1.58 ± 0.60 for skimmed milk. Conclusions: BHI may be a useful measure to identify the short-term hydration potential of different beverages when ingested in a euhydrated state. This trial was registered at www.isrctn.com as ISRCTN13014105. [ABSTRACT FROM AUTHOR]

Abstract: The major source of errors producing unreliable laboratory test results is the pre-analytical phase with hemolysis accounting for approximately half of them and being the leading cause of unsuitable blood specimens. Hemolysis may produce interference in many laboratory tests by a variety of biological and analytical mechanisms. Consequently, laboratories need to systematically detect and reliably quantify hemolysis in every collected sample by means of objective and consistent technical tools that assess sample integrity. This is currently done by automated estimation of hemolysis index (HI), available on almost all clinical chemistry platforms, making the hemolysis detection reliable and reportable patient test results more accurate. Despite these advantages, a degree of variability still affects the HI estimate and more efforts should be placed on harmonization of this index. The harmonization of HI results from different analytical systems should be the immediate goal, but the scope of harmonization should go beyond analytical steps to include other aspects, such as HI decision thresholds, criteria for result interpretation and application in clinical practice as well as report formats. With regard to this, relevant issues to overcome remain the objective definition of a maximum allowable bias for hemolysis interference based on the clinical application of the measurements and the management of unsuitable samples. Particularly, for the latter a recommended harmonized approach is required when not reporting numerical results of unsuitable samples with significantly increased HI and replacing the test result with a specific comment highlighting hemolysis of the sample. [Copyright &y& Elsevier]

Abstract: Background: Glycated hemoglobin (HbA1c) has a key role for diagnosing diabetes and monitoring glycemic state. As recently reviewed, available data on HbA1c biological variation show marked heterogeneity. Here we experimentally revaluated these data using a well designed protocol. Methods: We took five EDTA whole blood specimens from 18 apparently healthy subjects on the same day, every two weeks for two months. Samples were stored at −80°C until analysis and assayed in duplicate in a single run by Roche Tina-quant® Gen.2 immunoassay. Data were analyzed by the ANOVA. To assess the assay traceability to the IFCC reference method, we preliminarily carried out a correlation experiment. Results: The bias (mean±SD) of the Roche immunoassay was 0.3%±0.7%, confirming the traceability of the employed assay. No difference was found in HbA1c values between men and women. Within- and between-subject CV were 2.5% and 7.1%, respectively. Derived desirable analytical goals for imprecision, bias, and total error resulted 1.3%, 1.9%, and 3.9%, respectively. HbA1c had marked individuality, limiting the use of population-based reference limits for test interpretation. The estimated critical difference was ~10%. Conclusions: For the first time we defined biological variation and derived indices for the clinical application of HbA1c measurements using an accurately designed protocol and an assay standardized according to the IFCC. [Copyright &y& Elsevier]

• The management strategy of affected results in haemolysed samples is widely debated. • A dedicated approach tailored to the characteristics of young patients is desirable. • We propose an alternative approach for laboratory reports of paediatric wards. • Our report can act as a driving force for improving the phlebotomy quality. The management of affected results in haemolysed samples (HS) is debated. In an infant-maternity setting, for reporting interfered test results, we provided the result itself, the degree of haemolysis (as free haemoglobin concentration), and a warning recommending sample recollection. We investigated the impact of this approach on sample quality and clinicians' decision-making. Free haemoglobin was measured on Beckman Coulter AU680 as haemolytic index. We estimated the total HS number, the clinical wards more affected by HS, the most interfered analytes, and the retesting rate of interfered tests, by comparing data from Apr-Dec 2017, the period just after the introduction of the new policy, vs. Apr-Dec 2018. One year after the new report introduction, a significant HS decrease (5.8% vs. 7.8%, P < 0.001) was detected, together with a reduction of the frequency by which haemolysis affected results. The most affected wards, i.e., Paediatric and Neonatal Intensive Care Units, showed an improvement in sample quality (HS rate, 30.6% to 16.1%, P < 0.001, and 25.2% to 20.9%, P = 0.048, respectively). We noted a significant decrease in retesting after an alerted result for aspartate aminotransferase, magnesium, potassium, conjugated bilirubin, and lactate dehydrogenase. Our approach led to a HS decrease, suggesting that the provided report could be a driving force for improvement of phlebotomy quality, also helping clinicians in deciding if retesting is essential or not. [ABSTRACT FROM AUTHOR]

Abstract: Determination of serum soluble transferrin receptor (sTfR) has been proposed to identify iron-deficiency anemia (IDA) in patients affected by concurrent inflammatory disease that may spuriously increase ferritin concentration. The aim of this study was to critically review the available literature to assess the diagnostic efficacy of sTfR in complicated anemia. The criteria for study selection were: enrolment of patients with complicated anemia; bone marrow examination used as diagnostic gold standard for IDA; evaluation of sTfR vs. ferritin and binary data presentation. Six published studies met the criteria. However, the small size and wide heterogeneity of the studies did not allow us to conduct a meta-analysis. sTfR was overall more sensitive, even though it was evident that the ferritin sensitivity was influenced by selected cut-offs. Well-designed studies are still needed to define the added value, if any, of sTfR to ferritin for IDA detection in complicated anemia. [Copyright &y& Elsevier]

Background Automatic photometric determination of the hemolysis index (HI) on serum and plasma samples is central to detect potential interferences of in vitro hemolysis on laboratory tests. When HI is above an established cut-off for interference, results may suffer from a significant bias and undermine clinical reliability of the test. Despite its undeniable importance for patient safety, the analytical performance of HI estimation is not usually checked in laboratories. Here we evaluated for the first time the random source of measurement uncertainty of HI determination on the two Abbott Architect c16000 platforms in use in our laboratory. Methods From January 2016 to September 2017, we collected data from daily photometric determination of HI on a fresh-frozen serum pool with a predetermined HI value of ~ 100 (corresponding to ~ 1 g/L of free hemoglobin). Monthly and cumulative CVs were calculated. Results During 21 months, 442 and 451 measurements were performed on the two platforms, respectively. Monthly CVs ranged from 0.7% to 2.7% on c16000–1 and from 0.8% to 2.5% on c16000-2, with a between-platform cumulative CV of 1.82% (corresponding to an expanded uncertainty of 3.64%). Mean HI values on the two platforms were just slightly biased (101.3 vs. 103.1, 1.76%), but, due to the high precision of measurements, this difference assumed statistical significance (p < 0.0001). Conclusions Even though no quality specifications are available to date, our study shows that the HI measurement on Architect c16000 platform has nice reproducibility that could be considered in establishing the state of the art of the measurement. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Chromogranin A (CgA) and neuron-specific enolase (NSE) are biomarkers for neuroendocrine tumors. Although the knowledge of their biological variation (BV) is critical, only one study for CgA and no data for NSE are available. We report a definitive assessment of BV components of these biomarkers in the same cohort of subjects by an accurately experimental protocol. Design and methods: We collected five blood specimens from each of 22 healthy volunteers (10 men and 12 women, 23–54years) on the same day every two weeks for two months. Serum specimens were stored at −80°C until analysis and analyzed in a single run in duplicate. Data were analyzed by ANOVA. Results: Serum CgA concentrations were significantly higher for women than for men (P=0.01), whereas no difference was found for NSE. Intra-individual variance was not different between genders for both biomarkers. Within- and between-subject CVs were 16.3% and 33.5% for CgA and 13.6% and 11.5% for NSE, respectively. CgA showed marked individuality, suggesting that the use of population-based reference limits is inadequate for its interpretation. Conversely, the low individuality of NSE allows the use of a single reference interval. Reference change values were 46% for CgA and 39% for NSE. Desirable analytical goals for imprecision, bias, and total error were <8.2%, ±9.3%, and ±22.8% for CgA, and <6.8%, ±4.5%, and ±15.7% for NSE, respectively. Conclusion: In this study, we defined BV components of serum CgA and NSE and derived indices that may improve the clinical use of these biomarkers. [Copyright &y& Elsevier]

Abstract: Folic acid is believed to play a role in protection from oxidant stress. Low levels of folic acid had been found in serum from patients with Alzheimer disease (AD). Folate concentration was evaluated in sera from 136 patients with cortical dementia [AD, n =108; frontotemporal dementia (FTD), n =28], 57 patients with subcortical dementia [Lewy body disease (LBD), n =9; corticobasal degeneration (CBD), n =5; progressive supranuclear palsy (PSP), n =6; Parkinson disease with dementia (PD-Dem), n =37], and 76 nondemented, healthy age-matched people. Serum folic acid levels were decreased in patients with AD and FTD as compared with either controls or patients with subcortical dementia (3.60±2.22 and 5.37±2.92μg/L versus 6.87±3.50μg/L, respectively; P <0.01). A tendency towards decreased folate concentration was found in LBD and CBD, but not to a significant extent. The highest proportion of folate-deficient patients was found in CBD, FTD and AD (respectively, 60, 48.2 and 46.3% versus 7.9% in controls; P <0.001). Folate deficiency characterizes FTD as well as AD. These differences observed among different clinical dementing syndromes may be related to neocortical damage. [Copyright &y& Elsevier]