Hemolysis and blood gas analysis: it's time for a change!

Modern blood gas analyzers are not able to identify hemolysis, lipemia and icterus; therefore, the aim of this study was to assess the influence of hemolysis on blood gas samples. Blood gas analysis represents an essential part in the diagnosis and treatment of critically ill patients, including those affected by the pandemic coronavirus disease 2019 (COVID-19). Hemolysis, lipemia, and icterus, are causes of clinical misinterpretation of laboratory tests. A total of 1244 blood gas specimens were collected over a one-week period from different clinical wards, including the Emergency Department, and were assessed for serum indices on Cobas C6000 CE (Roche Diagnostics, Mannheim, Germany). The prevalence of hemolysis, lipemia, and icterus were 5%, 12%, and 14%, respectively. Sample storage at room temperature, delivery to central laboratory using pneumatic tube system, as well as small sample size, strongly affected blood gas parameters (p < .01). Hemolysis led to an increase in analytical bias for pH, pO2, and potassium, and a significant decrease for pCO2, HCO3-, sodium, and Ca2+ (p <.01). Currently, hemolysis detection systems are not yet widespread, and a rapid centrifugation of samples after blood gas analysis along with the assessment of serum indices represent the only prompt approach to identify unsuitable results, avoiding pitfalls in clinical decision-making, although it cannot be applied to the Emergency Department routine. Blood gas analyzers manufacturers and suppliers should implement automated built-in serum indices detection systems.

Arg tyrosine kinase modulates TGF-ß1 production in human renal tubular cells under high-glucose conditions.

Renal tubular cells are involved in the tubular interstitial fibrosis observed in diabetic nephropathy. It is debated whether epithelial-mesenchymal transition (EMT) affects tubular cells, which under high-glucose conditions overproduce transforming growth factor-ß (TGF-ß), a fibrogenic cytokine involved in interstitial fibrosis development. Our study investigated the involvement of non-receptor tyrosine kinase Arg (also called Abl2) in TGF-ß production. Human primary tubular cell cultures exposed to high-glucose conditions were used. These cells showed an elongated morphology, stress fibers and vimentin increment but maintained most of the epithelial marker expression and distribution. In these cells exposed to high glucose, which overexpressed and secreted active TGF-ß1, Arg protein and activity was downregulated. A further TGF-ß1 increase was induced by Arg silencing with siRNA, as with the Arg tyrosine kinase inhibitor Imatinib. In the cells exposed to high glucose, reactive oxygen species (ROS)-dependent Arg kinase downregulation induced both RhoA activation, through p190RhoGAPA (also known as ARHGAP35) modulation, and proteasome activity inhibition. These data evidence a new specific involvement of Arg kinase into the regulation of TGF-ß1 expression in tubular cells under high-glucose conditions and provide cues for new translational approaches in diabetic nephropathy.

High-dose intravenous immunoglobulins reduce nerve macrophage infiltration and the severity of bortezomib-induced peripheral neurotoxicity in rats.

BACKGROUND: Chemotherapy-induced peripheral neurotoxicity (CIPN) is a severe adverse effect in patients receiving antitumor agents, and no effective treatment is available. Although the mechanisms responsible for the development of CIPN are poorly understood, recent findings make neuroinflammation an attractive target to be investigated, particularly when neuropathic pain is a prominent feature such as after bortezomib administration. The aim of our study was to evaluate the effect of intravenous immunoglobulins (IVIg) delivery in chronic CIPN. The related neuro-immune aspects were investigated in a well-characterized rat model of bortezomib-induced peripheral neurotoxicity (BIPN). METHODS: After determination of a suitable schedule based on a preliminary pharmacokinetic pilot study, female Wistar rats were treated with IVIg 1 g/kg every 2 weeks. IVIg treatment was started at the beginning of bortezomib administration ("preventive" schedule), or once BIPN was already ensued after 4 weeks of treatment ("therapeutic" schedule). Neurophysiological and behavioral studies were performed to assess the extent of painful peripheral neurotoxicity induced by bortezomib, and these functional assessments were completed by pathologic examination of peripheral nerves and intraepidermal nerve fiber quantification (IENF). The role of the innate immune response in BIPN was investigated by immunochemistry characterization of macrophage infiltration in peripheral nerves. RESULTS: Both schedules of IVIg administration were able to significantly reduce bortezomib-induced heat and mechanical allodynia. Although these changes were not evidenced at the neurophysiological examination of peripheral nerves, they behavioral effects were paralleled in the animals treated with the preventive schedule by reduced axonopathy in peripheral nerves and significant protection from loss of IENF. Moreover, IVIg administration was very effective in reducing infiltration in peripheral nerves of macrophages with the M1, pro-inflammatory phenotype. CONCLUSION: Our results suggest a prominent role of neuroinflammation in BIPN and that IVIg might be considered as a possible safe and effective therapeutic option preventing M1 macrophage infiltration. However, since neuropathic pain is frequent also in other CIPN types, it also indicates the need for further investigation in other forms of CIPN.

Cerebrospinal fluid analysis and the determination of oligoclonal bands.

This document presents the guidelines for the cerebrospinal fluid (CSF) analysis and the determination of oligoclonal bands (OCBs) as pivotal tests in neuroinflammatory pathologies of the central nervous system. The guidelines have been developed following a consensus process built on questionnaire-based surveys, internet contacts, and discussions at workshops of the sponsoring Italian Association of Neuroimmunology (AINI) congresses. Essential clinical information on the pathologies in which the CSF analysis is indicated, and, particularly, on those characterized by the presence of OCBs in the intrathecal compartment, indications and limits of CSF analysis and OCB determination, instructions for result interpretation, and agreed laboratory protocols (Appendix) are reported for the communicative community of neurologists and clinical pathologists.

K index utility as diagnostic and prognostic biomarker in the assessment of patients with suspected Multiple Sclerosis.

The aim of the present study is to evaluate the composite role of k index in the initial assessment of Multiple Sclerosis (MS) patients and to select useful cut-offs exportable in clinical practice. We analysed CSF/serum samples of 140 patients and followed-up the CIS/MS subgroup for 7 years. Our results suggest κ index as a quantitative diagnostic and prognostic biomarker in MS, significantly associated to baseline lesion load and to successive clinical course. We propose k index ≥106 as a prognostic cut-off to select patients at major risk of relapse, potentially influencing initial therapeutic decisions.

Synchronization of cortisol circadian rhythm by the pineal hormone melatonin in untreatable metastatic solid tumor patients and its possible prognostic significance on tumor progression.

BACKGROUND: Cancer progression has been associated with neuroendocrine alterations involved in the control of the circadian rhythms, particularly those of cortisol. Moreover, the evidence of an altered cortisol rhythm may predict a poor prognosis in cancer patients. Finally, cancer progression has been proven to be associated with alterations in the pineal gland, which plays a fundamental role in the control of circadian biological rhythms. On this basis, a study was planned to evaluate the effects of a chronic treatment with the pineal hormone melatonin (MLT) in advanced cancer patients with altered cortisol circadian rhythm. PATIENTS AND METHODS: The study included 14 untreatable metastatic cancer patients showing alterations of cortisol rhythm. They were treated by MLT at 20 mg/day orally, in the evening, for 3 consecutive months. RESULTS: a normalization of cortisol rhythm was achieved in 4/14 (29%) patients. Moreover, stable disease (SD) was obtained in 6/14 (43%) patients under MLT therapy, whereas the other 8 patients had progressive disease (PD). Finally, the percentage of cortisol rhythm normalization achieved in patients with SD was significantly higher than that observed in patients with PD. CONCLUSION: These results show that MLT may normalize cortisol rhythm in advanced cancer patients and this effect appears to be associated with SD, thus confirming the negative prognostic significance of cortisol rhythm alterations in cancer.

[Pre-analytical errors in blood sampling: an observational study on specimen collection technique and laboratory results]. / Gli errori preanalitici nel prelievo ematico: uno studio osservazionale sulle modalità di raccolta dei campioni e sugli esiti di laboratorio.

INTRODUCTION: Around 60-70% of diagnostic and therapeutic decisions are based on blood exams. Several errors occur during the pre-analytic phase. AIMS: of this study were: to describe nurses' behaviours in blood specimen collection; to describe prevalence and type of pre-analytical errors; to assess the association between pre-analytical errors and occurrence of unsuitable specimens. METHODS: An observational cross-sectional study was conducted by means of a structured form based on up-to-date clinical recommendations. A researcher observed nurses' behaviors during 172 blood sampling procedures in medical, surgical and emergency care settings. Unsuitable procedures were registered. RESULTS: Most behaviours were correct, however some significantly diverged from recommended practices: active and passive patient identification; respect of antiseptic solution's drying time; rapid removal of tourniquet when blood started flowing. The prevalence of unsuitable specimen reports was significantly higher when the procedure involved a small calibre vein (RP: 0.19; IC95% 0.04 - 0.98; p = 0.03) and when blood drawing was difficult (RP; 3.83; IC95% 1.63 - 9.01; p <0.001). CONCLUSIONS: The pre-analytical phase is important for the diagnostic process and safety of patients. Although some factors ­ as patients' characteristics ­ are non-modifiable, some nurses' behaviours could be improved to reduce risk of pre-analytical errors. Further studies are needed to clarify the associations between pre-analytical errors and laboratory outcomes.

Endocrine effects of erythropoietin in cancer patients.

The recent advances in the knowledge of the psychoneuroimmunological pathogenesis of human neoplasms have demonstrated the existence of feed-back mechanisms operating between interleukins and endocrine secretions, which play an important role in the regulation of the immune responses, including the anticancer immunity. In contrast, few studies only have been performed to investigate the possible relation between endocrine activities and hematopoietic growth factors. The present study was performed to analyze the acute endocrine effects of erythropoietin-alpha (EPO) on the main endocrine secretions. The study was carried out in 10 advanced solid tumor patients. EPO was injected subcutaneously at a dose of 10,000 U, and venous blood samples were collected before and 2, 4 and 6 h after EPO administration. No significant changes in mean serum levels of FSH, LH and TSH were seen in response to EPO. Cortisol and DHEAS concentrations increased after EPO injection, whereas those of PRL decreased, but none of these differences was statistically significant. Finally, mean serum levels of both growth hormone (GH) and somatomedin-C (IGF-1) significantly decreased after EPO administration. This preliminary study shows that EPO may inhibit GH secretion from the pituitary gland and IGF-1 production. Since GH would stimulate EPO release, the results of this study may suggest the existence of feedback mechanism operating between GH secretion and EPO production, with inhibitory effect of EPO on GH secretion, and stimulatory action of GH on EPO production. Therefore, this study would describe the first example of hemato-endocrine feedback mechanisms. Moreover, this study, by showing an inhibitory effect of EPO on IGF-1 secretion, would suggest a possible use of EPO in the medical oncology not only for the treatment of cancer related anemia, but also to counteract tumor growth by blocking IGF-1 production, which has been proven to be a growth factor for several tumor histotypes. Obviously, IGF-1 is not the only tumor growth factor, but it could play a fundamental role in the regulation of production and activity of several other tumor growth factors. In any case, this study describes the only acute endocrine effects of EPO. Therefore, further studies, by evaluating the endocrine effects of a chronic treatment with EPO, will be required to establish which may be its effect on IGF-1 endogenous production, and its consequence on survival time.