Red blood cell deformability and aggregation in chronic venous disease patients with varicose veins

Introduction: Red blood cells’ (RBC) rheological properties are disturbed in chronic venous disease (CVD). The aim of the study was to compare deformability and aggregation of erythrocytes taken from the varicose vein and the antecubital vein of patients with chronic venous disease.Materials and Methods: Blood samples were taken from twelve CVD patients presenting clinical, aetiological, anatomical and pathological elements (CEAP) stages II and III. Blood was sampled from varicose veins and antecubital veins of patients (as control). Deformability and aggregation of RBC were analysed with a Laser-assisted Optical Rotational Cell Analyser (LORCA).Results: A significant increase in deformability was found in varicose vein RBC for shear stress values 4.24, 8.23 and 15.96 Pa as compared to RBC from the antecubital vein. The aggregation index was significantly lower and aggregation halftime was significantly increased for RBC taken from antecubital veins than for RBC from varicose veins.Discussion: In conclusion, RBC taken from varicose and antecubital veins of CVD patients are not entirely rheologically comparable and show different deformability and aggregation. Varicose vein RBC are more deformable and show a higher tendency for aggregation than antecubital vein RBC. Perhaps the deformability of varicose vein RBC has been increased as a compensation mechanism in subjects with CVD, due to increased resistance in their microcirculation

Changes in Red Blood Cell Properties and Platelet Function during Extracorporeal Membrane Oxygenation

Extracorporeal membrane oxygenation (ECMO) is associated with frequent hemorrhagic and thromboembolic complications. The multiple effects of ECMO include inflammatory response on contact with the circuit; hemolysis acquired von Willebrand syndrome likely affects the function of red blood cells (RBC) and platelets. The aim of this prospective observational study was to analyze RBC aggregation and elongation (deformability) and platelet aggregation in the first week of ECMO. Sixteen patients were included. Blood samples were taken prior to initiation of ECMO and on days 1, 2, 3, 5, and 7. RBC aggregation and elongation were analyzed using the laser-assisted optical rotational red cell analyzer (Lorrca). Upstroke, top, and amplitude as indices of aggregation showed significant time effects. RBC elongation was not affected at low shear stress. At high shear stress there was an increase in the elongation index at day 2 (p = 0.004), followed by a decrease. Platelet function was analyzed using multiple electrode aggregometry (Multiplate®). In pairwise comparison in the days 1–7 to the value prior to ECMO there was no significant difference in platelet aggregation by any of the three agonists (ADP p = 0.61; TRAP p = 0.77; Ristocetin p = 0.25). This implies that the rheology of RBCs seemed to be more affected by ECMO than platelets. Especially the red blood cell deformability continues to decline at higher shear stress

Rheological properties of erythrocytes in patients infected with Clostridium difficile

Clostridium difficile infection (CDI) is a bacterial infection of the digestive tract. Acute infections are accompanied by increased risk for venous thromboembolism (VTE). To date, there have been no studies of the rheological properties of blood during the course of digestive tract infections. The aim of our study was to examine the effects of CDI on red blood cell (RBC) rheology, specifically RBC deformability, RBC aggregation, and plasma viscosity. In addition, the activity of glucose 6 phosphate dehydrogenase (G6PD) and acetylcholinesterase (AChE) in RBC was studied. Our study group included 20 patients with CDI, 20 healthy persons comprised the control group. We examined the effects of CDI on the rheology of RBCs, their deformability and aggregation, using a Laser–assisted Optical Rotational Cell Analyzer (LORCA). Plasma viscosity was determined using a capillary tube plasma viscosymeter. Moreover, we estimated the activity of AChE and G6PD in RBC using spectrophotometric method. A statistically significant increase was found in the aggregation index, viscosity and activity of G6PD whereas the amount of time to reach half of maximum aggregation (t½) and the amplitude of aggregation (AMP) both showed statistically significantly decreases among patients with CDI compared to the control group. We also observed that the Elongation Index (EI) was decreased when shear stress values were low, between 0.3 Pa and 0.58 Pa, whereas EI was increased for shear stress in the range of 1.13 - 59.97 Pa. These observations were statistically significant. We report for the first time that acute infection of the gastrointestinal tract with Clostridium difficile is associated with abnormalities in rheological properties of blood, increased serum viscosity as well as increased aggregation of RBCs, which correlated with severity of inflammation. These abnormalities may be an additional mechanism causing increased incidence of VTE in CDI

Changes in the morphological, rheological, and biochemical blood indicators in triathletes

The aim of this study was to assess how the influence of intense physical effort changes the morphological, rheological, and biochemical blood indicators in triathletes. The study group comprised 10 triathletes aged 30-45 years, members of the Active Side of Life Association (Kraków, Poland). Venous blood was collected from the study participants twice, before and after the DiablakBeskid Extreme Triathlon 2016 (the Carpathians, Poland), and once from the control group for analysis of the selected blood indicators. Statistically significant changes were observed in the study group before and after the triathlon in morphological blood indicators, in the elongation index at the shear stress of 0.30 and 0.58 Pa, in levels of electrolytes, creatinine (mmol/l), serum protein parameters, and high-sensitivity troponin (ng/l). No such differences were reported for the remaining parameters. In turn, when comparing the study group before the triathlon with the control group, statistically significant differences were recorded in MCHC (g/dl), in the elongation index at the shear stress of 0.30 and 0.58 Pa, and Cl– (mmol/l) levels. No such differences were reported for the remaining parameters. Blood haematological and biochemical indicators in individuals that participate in triathlons characterize the actual range and direction of effort-related changes well and allow for the diagnosis of transient adaptive effects. Rheological parameters, involving the evaluation of erythrocyte deformability and aggregation, are useful for monitoring the particularly undesirable, short- and long-term effects of practicing extreme sports such as triathlons

The Influence of Early Onset Preeclampsia on Perinatal Red Blood Cell Characteristics of Neonates

Preeclampsia is the leading cause of complicated neonatal adaptation. The present investigation aimed to study the hemorheological factors during the early perinatal period (cord blood, 24 and 72 h after delivery) in newborns of early-onset preeclamptic mothers (n = 13) and healthy neonates (n = 17). Hematocrit, plasma, and whole blood viscosity (WBV), red blood cell (RBC) aggregation, and deformability were investigated. There were no significant differences in hematocrit. WBV was significantly lower in preterm neonates at birth than in the term 24 and 72 h samples. Plasma viscosity was significantly lower in preterm neonates’ cord blood than in healthy controls. RBC aggregation parameters were significantly lower in preterm newborns’ cord blood than in term neonates’ cord blood 24 and 72 h samples. RBC elongation indices were significantly lower in the term group than in preterm neonates 72 h’ sample at the high and middle shear stress range. Changes in the hemorheological parameters, especially RBC aggregation properties, refer to better microcirculation of preterm neonates at birth, which could be an adaptation mechanism to the impaired uteroplacental microcirculation in preeclampsia

Peripartum Investigation of Red Blood Cell Properties in Women Diagnosed with Early-Onset Preeclampsia

We investigated peripartum maternal red blood cell (RBC) properties in early-onset preeclampsia (PE). Repeated blood samples were taken prospectively for hemorheological measurements at PE diagnosis (n = 13) or during 26–34 weeks of gestation in healthy pregnancies (n = 24), then at delivery, and 72 h postpartum. RBC aggregation was characterized by M index (infrared light transmission between the aggregated RBCs in stasis) and aggregation index (AI—laser backscattering from the RBC aggregates). We observed significantly elevated RBC aggregation (M index = 9.8 vs. 8.5; AI = 72.9% vs. 67.5%; p < 0.001) and reduced RBC deformability in PE (p < 0.05). A positive linear relationship was observed between AI and gestational age at birth in PE by regression analysis (R 2 = 0.554; p = 0.006). ROC analysis of AI showed an AUC of 0.84 (0.68–0.99) (p = 0.001) for PE and indicated a cutoff of 69.4% (sensitivity = 83.3%; specificity = 62.5%), while M values showed an AUC of 0.75 (0.58–0.92) (p = 0.019) and indicated a cutoff of 8.39 (sensitivity = 90.9% and specificity = 50%). The predicted probabilities from the combination of AI and M variables showed increased AUC = 0.90 (0.79–1.00) (p < 0.001). Our results established impaired microcirculation in early-onset PE manifesting as deteriorated maternal RBC properties. The longer the pathologic pregnancy persists, the more pronounced the maternal erythrocyte aggregation. AI and M index could help in the prognostication of early-onset PE, but further investigations are warranted to confirm the prognostic role before the onset of symptoms

The Pathophysiology of Preeclampsia and Eclampsia

Preeclampsia is a hypertensive disorder of pregnancy, diagnosed after the 20th week of gestation in women experiencing new-onset hypertension along with symptoms affecting the liver, kidneys, or brain. In some cases, women with preeclampsia develop novel seizures or unexplained coma, at which time they are diagnosed with eclampsia. The mechanisms contributing to preeclampsia and eclampsia are not fully elucidated, although the placenta seems to play a critical role. Previous studies suggest that improper placentation stimulates mitochondrial dysfunction and the exaggerated release of placental-derived molecules including inflammatory cytokines, anti-angiogenic factors, reactive oxygen species, and cell-free nucleic acids into the maternal circulation that cause systemic vascular dysfunction. These, along with maternally derived molecules, act in concert, leading to hypertension and target organ damage during pregnancies complicated by preeclampsia and eclampsia.In this reprint, we present the original research articles and review papers published as part of the Special Issue: "The Pathophysiology of Preeclampsia and Eclampsia" in Cells