Changes In Mean Corpuscular Volume Research Articles

The possible role of the vasopressin system in hematopoiesis

Vasopressin is a pleiotropic hormone that controls body fluid homeostasis. Vasopressin has also been proposed to be involved in erythropoiesis, thrombocyte activity and inflammation. However, whether increasing vasopressin is associated with changes in hematopoietic markers is not known. To evaluate this gap of knowledge we measured the vasopressin marker copeptin and markers of erythropoiesis (erythrocyte count, hemoglobin (Hb), red blood cell distribution width (RDW), mean corpuscular volume (MCV), erythrocyte volume fraction (EVF)), leukocyte count (total count, lymphocytes, neutrophils) and thrombocyte count in 5312 participants from the Swedish CArdioPulmonary bioImage Study (SCAPIS). The associations between increasing copeptin tertile and the hematopoietic markers were analyzed in multivariate linear regression analyses. We found that increasing copeptin tertile was significantly (p < 0.001) associated with increasing erythrocytes, RDW, EVF, Hb, leukocytes and neutrophils after adjustment for age, sex, current smoking, prevalent diabetes, hypertension, creatinine, body mass index and physical activity. Increasing copeptin tertile was, however, not associated with change in MCV, lymphocyte or thrombocyte count. In conclusion, we found that increasing copeptin levels are positively associated with markers of erythropoiesis and leukocyte count in the general population. These results warrant further research on possible mechanistic effects of vasopressin on hematopoiesis.

Fetal Hemoglobin Decrease during Voxelotor Treatment

Sickle cell disease (SCD) is an inherited disorder caused by a point mutation in the β-globin gene leading to the formation of hemoglobin S (HbS). The polymerization of deoxygenated HbS is the first event in the molecular pathogenesis of SCD resulting in sickling of red blood cells (RBC), and hemolytic anemia which has been shown to be associated with organ damage and early death. Hemolytic anemia is defined by an accelerated rate of destruction RBC resulting in a lowered Hb level and a reduced gas transport capacity. Because Hb S in its oxy (R) conformation do not polymerize, drugs modifying hemoglobin (Hb) to increase the proportion of oxy-HbS have been propose to inhibit HbS polymerization. Voxelotor is such a molecule, which allosterically modifies Hb-oxygen affinity improving anemia and reducing hemolysis. However, the impact of Voxelotor on HbF levels is unknown. We describe here variations of %HbF and Mean corpuscular HbF (MCHbF) in a cohort of homozygous SCD patients treated with Voxelotor in our Sickle Cell Referral center. We conducted a prospective register study to analyze clinical and biological evolution of SCD patients treated with Voxelotor at 1500mg taken orally once daily. From December 2021 through December 2022, 25 SCD adult patients were followed during a median of 7 months [1-12]. Among them, HbF values were analyzable for 15 patients (SS gentype n=14; women in 73%; median age of 50 years [24-61]) who completed 6 months of Voxelotor with no transfusion during the same period; and with a stable dose of hydroxyurea (HU), for at least 3 months before inclusion and during the study in case of patients treated by HU (n=10). The dose of Voxelotor was stable for 13/15 patients and was decreased in 2 patients due to skin allergy (n=1) and moderate digestive intolerance. One patient died after 6 months of treatment in a context of end-stage renal failure and severe pulmonary hypertension not related to Voxelotor treatment. Mean corpuscular HbF (MCHbF) was calculated (MCHbF (pg) = MCH x %HbF). HbF percentage was measured by high performance liquid chromatography (Biorad, Variant II, beta-thal dual program). All participants provided written informed consent (CPP Erythropedie). From baseline to 6 months of follow up mean Hb (g/dL) concentration increased from 7.4 [5.4-8.5] to 8 [5-11.9] (p=0,0003; Figure A); absolute reticulocyte count (ARC ; Giga/L) decreased from 158 to 145 (p=0,005), %HbF decreased by 63% in all patients from 7,1% to 3,3% (p=0,008; Figure B) and MCHbF (pg) decreased from 3,36 to 1,03 (p=0,001; Figure D). A decrease in % HbF was observed from the first 15 days of treatment in both groups of patients treated or not with HU (Figure C) ; no changes in mean corpuscular volume (p=0.15) was observed in patients treated with HU during follow up. The HbF decrease in SCD patients treated with Voxelotor could be explained by different mechanisms: - Reduction of stress erythropoiesis which is due to an increase in erythroid output in response to anemic stress associated with a reduced expression of BCL11A, a transcriptional repressor that inhibits adult-stage HbF expression. This hypothesis is supported by the reduction in reticulocytes in patients treated with Voxelotor - The loss of an HbF-related survival advantage for SCD RBCs, while the normal RBC lifespan is approximatively 120 days, in SCD RBCs it is only a sixth of it. HbF is a major modulator of SCD and prolonge SCD RBCs survival. Its protective effect relies on its quantity and distribution among the RBC population, which is often heterogeneous in SCD patients. Protection against polymerisation of Voxelotor is probably more homogeneous among RBCs. As a result, RBCs containing low levels of HbF, which would normally disappear, have a prolonged lifespan. Similarly, it was presumed that sickling of erythroblasts could lead to ineffective terminal erythroid differentiation with an anti-apoptotic role for HbF during the terminal stages of erythroid differentiation. However we found no significant difference for index of ineffective erythropoiesis (soluble transferrin receptor / absolute reticulocyte count) before and after 6 months of treatment. The question raised is therefore that of the risk of a rebound effect upon discontinuation of Voxelotor, which has a short half-life, during the time it takes for HbF to increase. To better study this hypothesis, distribution of HbF/RBC will be studied in the HEMOPROVE trial (NCT05199766) currently in progress.

Defective iron homeostasis and hematological abnormalities in Niemann-Pick disease type C1.

Background: Niemann-Pick disease type C1 (NPC1) is a neurodegenerative lysosomal storage disorder characterized by the accumulation of multiple lipids in the late endosome/lysosomal system and reduced acidic store calcium. The lysosomal system regulates key aspects of iron homeostasis, which prompted us to investigate whether there are hematological abnormalities and iron metabolism defects in NPC1. Methods: Iron-related hematological parameters, systemic and tissue metal ion and relevant hormonal and proteins levels, expression of specific pro-inflammatory mediators and erythrophagocytosis were evaluated in an authentic mouse model and in a large cohort of NPC patients. Results: Significant changes in mean corpuscular volume and corpuscular hemoglobin were detected in Npc1 -/- mice from an early age. Hematocrit, red cell distribution width and hemoglobin changes were observed in late-stage disease animals. Systemic iron deficiency, increased circulating hepcidin, decreased ferritin and abnormal pro-inflammatory cytokine levels were also found. Furthermore, there is evidence of defective erythrophagocytosis in Npc1 -/- mice and in an in vitro NPC1 cellular model. Comparable hematological changes, including low normal serum iron and transferrin saturation and low cerebrospinal fluidferritin were confirmed in NPC1 patients. Conclusions: These data suggest loss of iron homeostasis and hematological abnormalities in NPC1 may contribute to the pathophysiology of this disease.

Defective iron homeostasis and hematological abnormalities in Niemann-Pick disease type C1

Background: Niemann-Pick disease type C1 (NPC1) is a neurodegenerative lysosomal storage disorder characterized by the accumulation of multiple lipids in the late endosome/lysosomal system and reduced acidic store calcium. The lysosomal system regulates key aspects of iron homeostasis, which prompted us to investigate whether there are hematological abnormalities and iron metabolism defects in NPC1. Methods: Iron-related hematological parameters, systemic and tissue metal ion and relevant hormonal and proteins levels, expression of specific pro-inflammatory mediators and erythrophagocytosis were evaluated in an authentic mouse model and in a large cohort of NPC patients. Results: Significant changes in mean corpuscular volume and corpuscular hemoglobin were detected in Npc1 -/- mice from an early age. Hematocrit, red cell distribution width and hemoglobin changes were observed in late-stage disease animals. Systemic iron deficiency, increased circulating hepcidin, decreased ferritin and abnormal pro-inflammatory cytokine levels were also found. Furthermore, there is evidence of defective erythrophagocytosis in Npc1 -/- mice and in an in vitro NPC1 cellular model. Comparable hematological changes, including low normal serum iron and transferrin saturation and low cerebrospinal fluidferritin were confirmed in NPC1 patients. Conclusions: These data suggest loss of iron homeostasis and hematological abnormalities in NPC1 may contribute to the pathophysiology of this disease.

Sunitinib-Induced Elevation of Mean Corpuscular Volume (MCV)-Exploring Its Possible Clinical Relevance in Cancer Patients.

Sunitinib is a broad-spectrum multitargeted tyrosine kinase inhibitor mainly used as second-line therapy for non-resectable gastrointestinal stromal or first-line treatment option of metastatic renal cell carcinoma (mRCC), and as an “off-label” option in pediatric oncology. It has been previously reported that sunitinib elevates the mean corpuscular volume of erythrocytes (MCV) in treated subjects. The aim of this study was to assess time-dependent changes of this effect and evaluate its possible clinical relevance. In this study, 179 adult and 21 pediatric patients with solid tumors treated with sunitinib were retrospectively analyzed. The laboratory and treatment-related data were collected for each treatment period. The regression model with a broken-line relationship was used to fit time dependence of the MCV. In the adult group, the MCV was increasing during the first 21.6 weeks (median) of treatment in a median level of 99.8 fL, where it stabilized. MCV increase was faster in the patients who suffered from treatment-related adverse events (21.3 vs. 24.6 weeks, p = 0.010). In the pediatric cohort, the MCV dynamics were similar to adults. In conclusion, MCV changes during sunitinib treatment in pediatric and adult patients may be of clinical utility in monitoring sunitinib treatment course.

Age-related changes in mean corpuscular volumes in patients without anaemia: An analysis of large-volume data from a single institute.

Although the mean corpuscular volume (MCV) has been associated with various diseases, these associations in relation to the age‐related trends in MCV remain unclear. Therefore, we used a dataset with over one million values to identify the relationship between ageing and MCV changes. All laboratory data obtained between November 1998 and November 2019 at Chungbuk National University Hospital were retrospectively collected. After excluding cases with missing values for individual complete blood count parameters, outlier MCV values, and ages less than 1 year and more than 88 years, 977,335 MCV values were obtained from 309,393 patients. Principal component analysis of blood components with ages and analysis of the median value changes for each blood component across decade‐wise age groups were conducted to identify relationships between ageing and changes in blood components. The median values of MCV showed gradual increments with age. The linear relationship for patients aged 1–25 years had a larger slope than that for patients aged 26–88 years. For MCV, the equation for patients aged 1–25 years was 0.40*(age) + 81.24 in females and 0.45*(age) + 79.58 in males. The equation for patients aged 26–90 years was 0.04*(age) + 88.97 in females and 0.06*age + 88.30 in males. Among patients aged >40 years, the MCV value was higher in men than in women. Analysis of a large dataset showed that the MCV gradually increased with age and the linear relationship differed between patients aged 1–25 and 26–88 years.

OA26 Erythrocyte mean corpuscular volume as a surrogate marker for methotrexate polyglutamation during early treatment in rheumatoid arthritis

Abstract Background/Aims The long-term outcomes for patients with rheumatoid arthritis (RA) depend on early and effective disease control. Methotrexate remains the key first-line disease-modifying therapy for the majority of patients. The gradual onset of action of methotrexate has been proposed to be linked to the build-up of intracellular stores of the drug, achieved through the process of polyglutamation. This is a complex and expensive assay. Recent work has shown an association between the increase in mean corpuscular volume (MCV) of erythrocytes and improvements in disease activity. This study seeks to relate intracellular methotrexate and 5-methyl-tetrahydrofolate polyglutamate concentrations with changes in MCV and their association with early ‘steroid free’ remission in RA patients. Methods 68 drug-naïve, newly diagnosed RA patients were recruited form the Newcastle Early Arthritis Clinic (NEAC). These patients were followed up for 6 months with serial blood sampling and quantification of the erythrocyte methotrexate and 5-methyl-tetrahydrofolate polyglutamate levels by liquid chromatography-mass spectrometry (LC-MS). This was then related to the contemporaneous erythrocyte MCV values from the clinical monitoring bloods on those occasions and the treatment outcome at 6 months. The outcome measure used was 4 component DAS28CRP remission (&amp;lt;2.4) with only the baseline intramuscular steroid permitted for the definition of remission. Results The majority of patients displayed a gradual increase in MCV over the first 6 months of treatment (MCV change from patient baseline used to normalise the data). When grouped by the ‘steroid free’ remission outcome, there was a divergence in MCV change with greater MCV increases observed in those achieving remission from 4 months of treatment onward (p &amp;lt; 0.05). In the same patient group, the accumulation of longer chain methotrexate polyglutamates (chain length 3 to 5) was observed to follow a similar trend to MCV with higher polyglutamate concentrations in those achieving the remission outcome from 2 months of treatment (P &amp;lt; 0.05). When the contemporaneous MCV and MTX polyglutamate samples were compared, an association was observed between the longer chain MTX polyglutamates and the change in MCV values (R2 = 0.39, p &amp;lt; 0.001), but not between intracellular 5-methyl-tetrahydrofolate and MCV (R2 = 0.01, p = NS). Conclusion Change in MCV shows an association with early remission induction with MTX therapy in treatment-naïve RA patients. This change in MCV appears to be associated with the accumulation of intracellular MTX metabolites, rather than via depletion of intracellular folates. MCV may therefore represent a tractable proxy measure of methotrexate polyglutamation for application in larger studies or for the purpose of drug monitoring. Disclosure P.M. Brown: None. A.G. Pratt: None. A.E. Anderson: None. A.W. Morgan: None. J.D. Isaacs: None.

Sex-Specific Differences of Adenosine Triphosphate Levels in Red Blood Cells Isolated From ApoE/LDLR Double-Deficient Mice

In this study for the first time, we investigated the correlation between sex-specific differences in adenosine triphosphate (ATP) levels in red blood cells (RBCs) and their mechanical, biochemical, and morphological alterations during the progression of atherosclerosis in ApoE/LDLR double-deficient (ApoE/LDLR−/−) mice. Our results indicate that both sex and age affect alterations in RBCs of both ApoE/LDLR−/− and C57BL/6J mice. When compared with male RBCs, female RBCs were characterized by lower basal ATP and mean corpuscular hemoglobin concentration (MCHC), higher hemoglobin concentration (HGB), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), deformability, and phosphatidylserine (PS) exposure levels, regardless of age in both, ApoE/LDLR−/− and C57BL/6J mice. ApoE/LDLR−/− mice compared with age-matched controls showed lower basal ATP levels regardless of age and sex. Intracellular ATP level of RBCs was decreased solely in senescent female C57BL/6J mice, while it was elevated in males. Basal extracellular ATP levels were 400 times lower than corresponding intracellular level. In conclusion, basal ATP levels, RBC morphology, deformability, PS exposure levels alterations are sex-dependent in mice. Changes in basal ATP levels were correlated with PS exposure and trends of changes in MCV. Trends of changes of the most RBC parameters were similar in both sexes of ApoE/LDLR−/− mice compared with age-matched controls; however, their kinetics and levels vary greatly between different stages of disease progression.

First Report of Reversible Macrocytic Anemia with Dysplastic Features Associated with Palbociclib Use in Patients with Metastatic Breast Cancer

Palbociclib is a reversible cyclin dependent kinase 4 and 6 (CDK4/6) inhibitor that is approved for the treatment of hormone-receptor positive metastatic breast cancer (ER+/HER2- MBC). CDK4/6 inhibitors exert their anti-tumor effect by preventing the G1 to S phase cell cycle transition, resulting in G1 cell cycle arrest. The most commonly reported hematologic side effect of palbociclib is neutropenia. Here we report 3 cases of reversible macrocytic anemia with dysplastic changes as a result of palbociclib use. Next, we present a retrospective study of 32 patients treated with palbociclib. Finally, CDK4 and CDK6 levels were measured in CD34+ stem/progenitor cells (HSPC) from myelodysplastic syndrome (MDS) patients and compared to healthy controls.Methods & ResultsFour months into starting treatment with palbociclib plus an aromatase inhibitor for refractory ER+/HER2- MBC, 3 female patients developed macrocytic anemia, with a mean corpuscular volume (MCV) of >100 femtoliters per cell (fL) and a decrease in hemoglobin (Hb) by 2 grams per deciliter (g/dL). Work-up for macrocytosis was unrevealing except for peripheral blood smears showing dysplastic changes including pseudo-Pelger-Huёt anomaly, suggestive of MDS (see Figure (Fig) 1). Bone marrow aspirates were obtained, which also showed morphology similar to MDS including hypocellular marrow (10% cellularity), dysplastic erythroid forms including binucleated forms and nuclear budding, and small hypolobated megakaryocytes (see Fig 2). Cytogenetic, molecular, and flow analyses were normal. Patients were managed expectantly, and when palbociclib was discontinued for breast cancer progression, the macrocytic anemia resolved to baseline Hb and MCV values within 4 months of stopping therapy.A retrospective study to assess hematological characteristics of 32 patients with ER+/HER2- MBC treated with palbociclib for more than 3 months between 1/1/2015 to 3/1/2017 was performed. Statistical analysis included Wilcoxon signed-rank test and Kaplan Meier estimator. Median age was 65 years and 10 (31%) patients had received prior chemotherapy (see Table 1). Median baseline MCV was 89.75 fL compared to 100.5 fL post palbociclib (p <0.0001), and 16 (52%) patients developed macrocytosis (MCV >100 fL). The median progression-free-survival (PFS) for patients who developed a significant MCV increase (highest MCV >10 fL from baseline MCV) was 422 days compared to 216 days for those without a significant MCV increase (highest MCV ≤10 fL from baseline MCV) (HR 0.29, p=0.035). However, this PFS difference was not seen when the change in MCV was analyzed as a time-dependent variable.As palbociclib treatment appears to induce hematologic and bone marrow changes phenotypically similar to MDS, we examined whether alterations in CDK4/6 expression is observed in human MDS. We evaluated CDK4 and CDK6 expression by qRT-PCR in 183 samples from MDS patient-derived HSPC and 17 healthy marrow control HSPC and found that CDK6, but not CDK4, expression was significantly decreased in MDS HSPC when compared to healthy HSPC (p=0.04) (see Fig 3). We then evaluated MDS phenotype by high (>median) and low (≤median) CDK6 expression, and found that patients with low CDK6 expression had a 1 g/dL lower Hb at presentation when compared to those with high CDK6 expression (p=0.001). Further, when healthy marrow HSPC were treated with palbociclib in vitro, we observed a dose dependent decrease in erythroid colony formation and maturation, replicating the anemia phenotype seen in patients.In conclusion, palbociclib treatment can cause a reversible macrocytic and dysplastic anemia. Macrocytosis is a potential indicator of in vivo CDK4/6 inhibition that could be associated with increased PFS in patients with ER+/HER2- MBC who are treated with palbociclib. Low CDK6 expression in MDS correlates with a worsened anemia phenotype. Further clinical studies with larger sample sizes are needed. Continued safety monitoring of patients on palbociclib is suggested. [Display omitted] DisclosuresSteidl:Aileron Therapeutics: Consultancy, Research Funding; GlaxoSmithKline: Research Funding; Novartis: Research Funding; Celgene: Consultancy; Bayer Healthcare: Consultancy.

O07 The increase in erythrocyte mean corpuscular volume by methotrexate is potentiated by hydroxychloroquine and is an early indicator of clinical response in rheumatoid arthritis

Background/Aims Rheumatologists are facing a significant challenge in the management of early rheumatoid arthritis (RA) due to limitations placed on outpatient visits during the COVID-19 pandemic. Frequent clinical assessments of disease activity are recommended during implementation of the treat to target strategy to achieve remission. A biomarker indicating response to methotrexate during the early phase of therapy could complement clinical examination. Methotrexate increases erythrocyte mean corpuscular volume (MCV), which is measured routinely, prompting us to investigate whether changes in MCV could act as an early indicator of response. Methods Patients with early RA who were started on methotrexate therapy were included from two independent cohorts. The larger cohort (discovery cohort, n = 655) was used to build the model and the second cohort (validation cohort, n = 225) was applied to test the prediction of the model. Conventional statistical, and machine learning approaches were adopted to identify key determinants that influence the potential relationship between MCV and clinical response, defined as attainment of remission or low disease activity, at six months after starting methotrexate. Results A LASSO penalised logistic regression model was built with the discovery cohort [area under the receiver operating characteristics (AUROC) curve = 0.76], where change of MCV from three months [Odds ratio (OR) 1.53 (95% CI 1.38-1.70)], concomitant use of hydroxychloroquine [OR 2.16 (95% CI 1.52 - 3.07, p < 0.001)], and seropositivity [OR 1.83 (95% CI 1.12 - 3.03, p = 0.02)] were associated with favourable methotrexate response [accuracy 81% (95% CI 76%-86%) of the model testing against discovery model]. Different machine learning classification methods were applied. Random forest exhibited the maximum accuracy and AUROC (89%, and 86%, respectively), confirming the above three predictors as the most significant. Two latent classes (class 1: smaller MCV increase and class 2: greater MCV increase) were identified based on the MCV changes over six months. Class 1 had fewer responders and a lower number of patients on hydroxychloroquine compared to class 2. The earliest time point of significant difference of MCV between responders and non-responders was three months [mean difference 1.43 (95% CI 0.57-2.3)]. Combination hydroxychloroquine and methotrexate caused the greatest increase in MCV with a difference between responders and non-responders at 2 months. Change of MCV at three months showed AUROC of 0.75 to predict treatment response to the combination of methotrexate and hydroxychloroquine at six months with an optimal cut-point of MCV 3.5 fL (95% CI 3.5-3.6) with 71% sensitivity and 75%, specificity. Conclusion Our data provides mechanistic insight into the synergistic clinical benefit of concomitant hydroxychloroquine with methotrexate, boosting the rise in erythrocyte MCV which could serve as an early biomarker of treatment response. Disclosure M.R. Shipa: Grants/research support; Versus arthritis. S. Yeoh: Grants/research support; Royal College of Physicians, Rosetrees Trust, NIHR University College London Hospitals Biomedical Research Centre, UCLH Charities. A. Embleton-Thirsk: None. D. Mukerjee: None. M.R. Ehrenstein: Grants/research support; University College London Hospital Biomedical Research Centre.

Dhatri Lauha in the management of iron deficiency anemia: A prospective open-label single-arm multi-center trial.

The burden of iron-deficiency anemia (IDA) remains persistently high in India due to the poor tolerability of oral iron supplementation. Therefore, more focus is required to explore traditional medicine for safe and effective options for managing IDA. To assess the clinical safety and efficacy of Dhatri Lauha in patients with IDA. An open-label, prospective, single-arm, multi-center trial was conducted at 12 centers with a sample size of 40 participants per study site. Patients with IDA aged 18-60 years with hemoglobin levels in the range of 6-10gm/dl, mean corpuscular volume (MCV) <80 fl, mean corpuscular hemoglobin concentration (MCHC) <34 μg/dl, serum ferritin <30 μg/dl and serum iron <50 μg/dl were included in the study. Dhatri Lauha 500 mg capsule was administered twice daily with lukewarm water after meals for 45 days. The primary outcome measure was the change in hemoglobin (Hb%) level from baseline to day 45. Secondary outcome measures included the change in MCV, MCHC, serum iron and ferritin levels, incidence of adverse events, and change in safety parameters (liver and kidney function tests). The mean (statistical) change in outcome measures from baseline to day 45 was compared using a paired sample t-test. Out of 458 participants enrolled in the study, 400 contributed to the final analysis. A significant difference was observed in the outcome parameters such as Hb%, MCV, MCHC, serum ferritin, and serum iron levels (P < 0.001) after 45 days of treatment. Mean Hb% changed from 8.46 ± 1.14 g/dl at baseline to 9.18 ± 1.61 g/dl on day 45 (P < 0.001). LFT and KFT were within the normal limits after the study period. No participant withdrew from the study due to adverse events. Dhatri Lauha is a safe intervention and can be expected to improve hemoglobin levels, red blood cell parameters, and iron stores in patients with IDA. Future RCTs with a larger sample size, standard care as control and a longer follow-up may produce more accurate and reliable results.

Inherited microcytic anemias.

Inherited microcytic anemias can be broadly classified into 3 subgroups: (1) defects in globin chains (hemoglobinopathies or thalassemias), (2) defects in heme synthesis, and (3) defects in iron availability or iron acquisition by the erythroid precursors. These conditions are characterized by a decreased availability of hemoglobin (Hb) components (globins, iron, and heme) that in turn causes a reduced Hb content in red cell precursors with subsequent delayed erythroid differentiation. Iron metabolism alterations remain central to the diagnosis of microcytic anemia, and, in general, the iron status has to be evaluated in cases of microcytosis. Besides the very common microcytic anemia due to acquired iron deficiency, a range of hereditary abnormalities that result in actual or functional iron deficiency are now being recognized. Atransferrinemia, DMT1 deficiency, ferroportin disease, and iron-refractory iron deficiency anemia are hereditary disorders due to iron metabolism abnormalities, some of which are associated with iron overload. Because causes of microcytosis other than iron deficiency should be considered, it is important to evaluate several other red blood cell and iron parameters in patients with a reduced mean corpuscular volume (MCV), including mean corpuscular hemoglobin, red blood cell distribution width, reticulocyte hemoglobin content, serum iron and serum ferritin levels, total iron-binding capacity, transferrin saturation, hemoglobin electrophoresis, and sometimes reticulocyte count. From the epidemiological perspective, hemoglobinopathies/thalassemias are the most common forms of hereditary microcytic anemia, ranging from inconsequential changes in MCV to severe anemia syndromes.

Erythrocyte Characteristics and the Risk of Depression in Late Life: A Population-Based Prospective Study

ObjectivesInflammation and vascular dysregulation may contribute to the development of depression and impose a burden on erythropoiesis. This study aimed to identify the association of erythrocyte indices with the severity of depressive symptoms and risk of developing depressive disorders in the older people. DesignA prospective cohort study on a randomly sampled Korean older population; the baseline assessment from 2010 to 2012, the first follow-up assessment from 2012 to 2014, and the second follow-up assessment from 2014 to 2016 (mean follow-up duration = 3.4 years). SettingA nationwide and community-based cohort. ParticipantsA total of 4451 Koreans aged 60 years or older. MethodsWe examined the associations of the values and changes in mean corpuscular volume, mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) with the risk of prevalent and incident depression using logistic regression analyses. ResultsHigh MCH and MCHC in female participants and high MCHC in male participants were associated with high geriatric depression scale scores and risk of prevalent depression. In female participants, high- and middle-MCH tertile groups showed a 2.68- and 2.34-fold higher risk of incident depression than did the low tertile group. In male participants, the high-MCH tertile group showed a 1.79-fold higher risk of incident depression than did the low tertile group. In both sexes, the participants whose MCV changed to the high or middle tertile or remained in the high or middle tertile during the follow-up period, and whose MCH increased to the high tertile or remained in the high tertile, were at a higher risk of incident depression. Conclusions and ImplicationsChanges in erythrocyte may be associated with the risk of depression in older adults. This prospective study proposes a new perspective of the old hematologic parameters for understanding the pathophysiology of late-life depression.

Iron Sucrose in Patients with Left Ventricular Assist Devices and Iron Deficiency

Intravenous iron repletion in patients with heart failure with reduced ejection fraction (HFrEF) and iron deficiency has been shown to safely improve functional capacity and quality of life. Despite common use of intravenous (IV) iron repletion in patients with left ventricular assist devices (LVADs) and iron deficiency, there is insufficient evidence regarding outcomes in this patient population. In this study, we quantified safety and efficacy endpoints in patients with LVADs and iron deficiency who were treated as inpatients with IV iron sucrose. We performed a retrospective analysis of patients on LVAD support with iron deficiency who received inpatient IV iron sucrose. Patient data was collected from a single, large academic medical center between 3/2017 and 7/2019. The primary endpoint was change in hemoglobin from baseline to 12 weeks post-infusion. Secondary endpoints were a change in mean corpuscular volume (MCV), ferritin, transferrin saturation, or New York Heart Association (NYHA) class from baseline to 12 weeks post-infusion. Safety endpoints included anaphylaxis, arrhythmias, or infections post-infusion and during admission. Iron deficiency was pre-defined as ferritin <100 ug/L or ferritin 100-299 ug/L with iron saturation < 20%. Patients with previous IV iron administration were excluded. A total of 54 patients (median age 59, IQR 50-68, 80% male) on LVAD support with iron deficiency received inpatient iron sucrose infusions between 3/2017 and 7/2019. Mean difference in hemoglobin at 12 weeks post-infusion was +2.2 g/dL (9.3 to 11.5 g/dL; p <0.001). Excluding patients who received blood products prior to the hemoglobin result at 12 weeks (17%, N=9), the mean difference was similar: +2.4 g/dL (9.3 to 11.7 g/dL; p <0.001). Prior to iron infusion, 35% of patients had an NYHA I or II compared to 73% at 12 weeks post infusion (p <0.001). Following IV iron administration, no patients experienced anaphylaxis, 2% had arrhythmias, and 3% had infections. Use of IV iron therapy in patients with continuous-flow LVAD is well-tolerated and associated with longitudinal improvements in hemoglobin and functional capacity. This adds to limited data regarding IV iron use in patients supported by LVAD.

Changes in Mean Corpuscular Volume and RBC Distribution Width Predict Erythrocyte Engraftment Following ABO-Incompatible Hematopoietic Stem Cell Transplantation.

The purpose of this study was to identify laboratory parameters representing erythrocyte engraftment to be used as an indicator to change the recipient to donor ABO group and Rh type following an ABO-incompatible hematopoietic stem cell transplant (HSCT). Studies have shown that ABO incompatibility does not have an effect on outcome of HSCT; however, the serologic consequences of these ABO-incompatible transplants can make it difficult to decide when to begin support with donor ABO/Rh-type blood products. This study explored the use of RBC distribution width (RDW), mean corpuscular volume, and hemoglobin as regularly tested laboratory parameters that could be used as surrogate markers for RBC engraftment in 65 patients who received ABO/Rh-incompatible HSCT. The appearance of engrafted donor RBCs correlated with a peak in RDW (P = .002). In addition, our findings suggest that serologic changes in ABO/Rh appear to correspond with a peak in RDW (P = .002). High values of RDW likely result from a substantial proportion of large, young erythrocytes from recent engraftment with smaller, older pretransplant erythrocytes from the recipient. Our findings suggest that peak RDW may be an indicator of erythrocyte engraftment, following an ABO/Rh-incompatible HSCT.

Abstract P1-19-42: Evaluation of mean corpuscular volume (MCV) as a pharmacodynamic predictive biomarker in patients receiving CDK4/6 inhibitors for metastatic breast cancer (MBC)

Abstract Introduction: CDK 4/6 inhibitors (CDK4/6i) are FDA approved for treatment of hormone receptor (HR) positive, HER2 negative metastatic breast cancer (MBC). Recent work demonstrated that a rise in MCV was correlated with longer median progression free survival (Anampa et al, Haemoatologica 2018). We performed a single-institution retrospective analysis to evaluate whether palbociclib induced early changes in MCV serve as a pharmacodynamic biomarker to predict response to CDK4/6i. Methods: We identified a retrospective cohort of 81 patients with HR+, HER2- MBC treated with CDK4/6i as first line metastatic treatment at Mayo Clinic, Rochester. Hematologic indices were abstracted pretreatment and at the start of each cycle through the start of cycle 4 (C4). Wilcoxon signed test was used to examine the changes in MCV (ΔMCV) comparing pretreatment up to C4 and ΔMCV between cycles. Optimal cut points for ΔMCV were determined using Cutoff finder (Budczies et al., PLOS One 2012). Cox proportional hazard regression analysis was performed to evaluate associations of MCV and time to treatment failure (TTF), which was defined as the time from the start of the analyzed cycle to treatment discontinuation for any reason(in months). As eight comparisons were made, a Bonferroni correction established p-value &amp;lt;0.00625 as the adequate cutoff for statistical significance. Statistical analyses were performed using JMP (SAS Institute Inc, Cary, NC). Results: 60/81 patients had pretreatment and at least one subsequent lab data point that included MCV. The pretreatment mean hemoglobin (Hgb) was 12.8 [standard deviation (SD) 1.37 g/dL] and 6/60 (10.2%) patients with Hgb &amp;lt;11.0 g/dL. Mean pretreatment MCV was 89.0 femtoliters/cell [fl (SD 4.63)] and no macrocytosis (defined as MCV &amp;gt;100 fl) was observed. At C4, the mean Hgb was 12.1 g/dL (SD 1.11) with 4/49 (8.2%) with Hgb &amp;lt;11.0 g/dL. The C4 mean MCV was 96.6 fl (SD 5.23) and 8/29 (16.3%) developed macrocytosis. Wilcoxon signed analysis showed a significant increase in ΔMCV pretreatment to C2 [n=51, median 1.5 with interquartile range (IQR) -0.1-3.2, p&amp;lt;0.0001], C2 to C3 (n=44, median 2.9, IQR 1.4-5.2, p&amp;lt;0.0001), and C3 to C4 (n=41, median 3.4, IQR 1.9-4.9, p&amp;lt;0.0001). A rise in MCV≥8.15 from pretreatment to C4 was associated with a non-statistically significant improvement in TTF [n=49, hazard ratio (HR) 0.38, p = 0.06]. Between C2 and C3, a rise in MCV ≥2.9 was associated favorably with TTF (n=44, HR 0.36, p = 0.029). The estimated probability of remaining on treatment at 30 months was higher in those with C2-C3 ΔMCV ≥2.9 [44.1%; 95% Confidence Interval (CI) 17.3-68.2%] compared to those with a C2-C3 ΔMCV &amp;lt;2.9 (10.1%; 95%CI 1.5-28.7%). Discussion: We observed an increase in MCV in all patients receiving CDK4/6i by start of C4. The rise in MCV during CDK4/6i treatment may reflect drug induced cell-cycle arrest in hematopoietic cells. Evaluation in larger studies is needed to validate dynamic changes in MCV as a predictive biomarker of response to CDK4/6i therapy. Citation Format: Grace Mei Yee Choong, Roberto A Leon-Ferre, Ciara C O'Sullivan, Kathyrn J Ruddy, Tufia C Haddad, Timothy J Hobday, Prema P Peethambaram, Charles L Loprinizi, Minetta C Liu, Vera J Suman, Matthew P Goetz, Karthik V Giridhar. Evaluation of mean corpuscular volume (MCV) as a pharmacodynamic predictive biomarker in patients receiving CDK4/6 inhibitors for metastatic breast cancer (MBC) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-19-42.

Ameliorative effects of vitamin B17 on the kidney against Ehrlich ascites carcinoma induced renal toxicity in mice.

Cancer is the major cause of death and many factors that lead to its occurrences, such as environmental pollution and pesticides and other factors. Ehrlich carcinoma development depends on many things associated with the environment, nutrition, personal habits, and family history. The present study aimed to evaluate the potential protective effects of vitamin B17 (VB17) against Ehrlich ascites carcinoma (EAC) that induced kidney toxicity in female mice. The mice were divided into five groups (first group, control group; second group, VB17 group; third group, EAC group; fourth group, pretreated EAC with VB17; fifth group, cotreated EAC with VB17). Results showed the VB17 in pretreated (G4) and cotreated (G5) groups lead to an improvement in DNA damage and cytological examination, in addition significantly (P < .05) increase in Na+ , red blood cell, hemoglobin, hematocrit value, mean corpuscular hemoglobin (MCH), and MCH concentration, whereas significantly (P < .05) decrease in urea, creatinine, K+ , platelets, and white blood cells while insignificant (P < .05) changes in mean corpuscular volume when compared to the EAC group. Many histopathological changes were observed in kidney sections in EAC as marked damage and degenerated, glomerular atrophy, the Malpighian corpuscles that lost their characteristic configuration. On the other hand, a moderate improvement and arrangement in the kidney histological structure in pretreated VB17 + EAC, while a mild enhancement and arrangement of the kidney structure in cotreated EAC + VB17. In addition, depletion in renal P53 and PCNA protein expression compared with the EAC group. It could be concluded that VB17 has a potential renal protective effect against EAC cells induced kidney injury.

Concomitant Hydroxyurea and Voxelotor: Results from the HOPE Study

Background: Sickle cell disease (SCD) is a chronic, debilitating disorder caused by a mutation in beta globin, which leads to the production of sickle hemoglobin (HbS). Deoxygenated HbS polymerization results in red blood cell (RBC) sickling, which leads to anemia, hemolysis, vaso-occlusion, and organ damage. Voxelotor a first-in-class therapy in development for the treatment of SCD, stabilizes HbS in the oxygenated state and has been shown to reduce anemia and hemolysis. Hydroxyurea induces fetal hemoglobin (HbF) and is an FDA- and EMA-approved treatment for SCD. Because both voxelotor and hydroxyurea can affect anemia and hemolysis, and potentially have additive mechanisms of protection against HbS polymerization, the effects of concomitant hydroxyurea in the setting of voxelotor treatment were investigated. The objective of this analysis was to evaluate RBC parameters, such as hemoglobin (Hb), mean corpuscular volume (MCV), %HbF, absolute reticulocyte count (ARC), and red cell distribution width (RDW), as well as the absolute neutrophil count (ANC) to examine the potential impact of concomitant hydroxyurea use on the effects of voxelotor and on medication adherence during the treatment period. Serum erythropoietin (EPO) levels were also monitored to investigate the effects of increased Hb concentrations on oxygen delivery. Methods: The HOPE study is a phase 3, randomized, placebo-controlled, double-blind, multicenter study comparing the efficacy and safety of voxelotor (1500 mg and 900 mg daily) versus placebo in participants aged 12 to 65 years with SCD. A per-protocol analysis was performed using available data for all participants at the interim data cutoff on October 31,2018. Concomitant hydroxyurea treatment was permitted per protocol if the dose was stable at enrollment and maintained, unless dose adjustments were required due to toxicities. Laboratory parameters were compared in participants with or without concomitant hydroxyurea use. Results: From the HOPE study, 274 participants with lab values for the specified parameters (Hb, MCV, %HbF, ARC, RDW, ANC, EPO) available through week 24 were analyzed. A total of 179 of 274 (65%) participants were receiving hydroxyurea at study enrollment, and they were evenly distributed across the 3 treatment arms. Baseline lab values documented the effects of current hydroxyurea treatment, with higher average Hb, MCV, and %HbF but slightly lower average ARC and ANC compared with those not receiving hydroxyurea. Voxelotor treatment led to significant dose-dependent Hb increases, regardless of concomitant hydroxyurea therapy (Table 1), but the average MCV, %HbF, ANC, and RDW were unchanged. A lower average ARC was noted, which was attributed to the increased Hb level, whereas EPO levels showed wide variability but no significant changes from baseline. Conclusions: The HOPE study demonstrated that voxelotor treatment increased Hb levels in study participants with SCD, irrespective of hydroxyurea use. Significant voxelotor-associated Hb increases were observed for participants on stable-dose hydroxyurea and were equivalent to those observed in participants not taking hydroxyurea. The lack of observed changes in MCV and ANC was consistent with stable hydroxyurea exposure throughout the treatment period, thus addressing questions about potential changes in hydroxyurea compliance during the study. The additive treatment effects on anemia and hemolysis by voxelotor suggest that combination therapy with hydroxyurea may be safe and effective for optimal disease modification. Disclosures Ware: Addmedica: Other: Research Drug Donation; CSL Behring: Membership on an entity's Board of Directors or advisory committees; Novartis: Other: DSMB; Nova Laboratories: Membership on an entity's Board of Directors or advisory committees; Global Blood Therapeutics: Membership on an entity's Board of Directors or advisory committees; Agios: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Other: Research Drug Donation. Brown:Novartis, Inc: Research Funding; Imara, Inc: Consultancy, Research Funding; Global Blood Therapeutics, Inc: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Research Funding. de Montalembert:bluebird bio, Inc: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; AddMedica: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Tonda:Global Blood Therapeutics: Employment, Equity Ownership. Tong:Global Blood Therapeutics: Employment, Equity Ownership. Hoppe:Novartis: Consultancy; Bioverativ: Consultancy; Global Blood Therapeutics: Employment, Equity Ownership; Imara: Consultancy. Lehrer-Graiwer:Global Blood Therapeutics: Employment, Equity Ownership. Abboud:Novartis: Consultancy, Honoraria, Research Funding; GBT: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AstraZeneca: Membership on an entity's Board of Directors or advisory committees, Research Funding; Modus: Research Funding; Novo Nordisk: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Eli Lilly: Research Funding; Amgen: Other: Travel support; CRSPR Therapeutics: Membership on an entity's Board of Directors or advisory committees.

Changes of the erythrocyte phenotype and blood biochemistry in dairy calves during the first ten weeks of age.

BackgroundBovine erythrocytes undergo important changes in their morphology and chemical composition during the first weeks of age, which must be understood to accurately interpret hematology results in calves. The objectives of this prospective cohort study were to describe physiological changes of calf erythrocytes and to investigate mechanisms potentially causing these changes.MethodsBlood samples from 30 clinically healthy dairy calves were obtained from birth to the tenth week of age in weekly intervals. Hematological and plasma biochemical parameters as well as the mineral electrolyte content of erythrocytes were determined and followed over time. The changes of parameters characterizing the erythrocyte phenotype over time were compared to the changes of plasma and erythrocyte biochemical parameters and possible associations were investigated using correlation and stepwise regression analyses.ResultsAlthough the erythrocyte mean corpuscular volume (MCV) declined from 43.6 ± 3.7 fL to 35.6 ± 3.2 fL between the first and seventh week, the red blood cell count (RBC) increased from 7.2 ± 1.1 × 1012/L to 9.3 ± 1.0 × 1012/L until the fifth week of age. The blood hemoglobin (Hb) concentration increased from 0.96 ± 0.16 g/L to 1.16 ± 0.11 g/L in the first three weeks of age and remained at this level until the end of the study. Changes in MCV were accompanied by a decline of the erythrocyte potassium content (KERY) from 91.9 ± 13.5 to 24.6 ± 7.2 mmol/L and a concomitant increase of the erythrocyte sodium content from 45.0 ± 32.0 to 102.7 ± 26.5 mmol/L. MCV was found to be associated with KERY, the primary determinant of the intra-erythrocyte osmotic pressure from the sixth week of age and with blood hemoglobin, the primary determinant of the intra-erythrocyte oncotic pressure from the eighth week of age, when KERY, blood Hb and MCV already had reached or approached normal levels of adult cattle. The plasma iron concentration was not found to be associated to any of the studied hematological parameters.ConclusionA volume reduction of 20% in bovine neonatal erythrocytes is a physiological change occurring during the first weeks of age and is neither associated with sideropenia nor with anemia in healthy calves. The mechanism driving the observed erythrocyte volume change could not be identified. Results of the correlation and regression analyses indicate that changes in intra-erythrocyte osmotic or oncotic pressure are improbable underlying causes. Results reported here show that KERY is an unreliable indicator for the K homeostasis of the intracellular space in neonatal calves and that a decrease in MCV in early life per-se is an unreliable indicator for the development of microcytic anemia.

Aconitum Napellus: Detoxification and Acute Toxicity Investigation Followed by Sub-Acute Toxicity and Bioavailability Assessment of Highest and Lowest LD50 Extract

In spite of high toxicological risk Aconitum napellus (ACON) is tremendously used for the treatment of rheumatoid and joint pain. The acute toxicity study was assessed for cow milk treated (CMT), goat milk treated (GMT) and water treated (WT) extracts of Aconitum napellus (ACON) in mice, expressed as LD50 (25, 50, 10 and 5 mg/kg respectively). The sub-acute toxicity of ACON (0.5 mg/kg/day) and GMT (5 mg/kg/day) were also performed in SD-rats for 28 days. The GMT not showed any treatment related changes, however ACON produced significant clinical changes in mean corpuscular volume and mean corpuscular hemoglobin level. Moreover creatinine, bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase levels significantly increased (p < 0.001), and abnormal histoarchitecture of kidney and liver were also observed as compared to control. In vivo pharmacokinetic study also confirmed that GMT constituted lesser amount of aconitine (Cmax = 1.84±1.98) than standard aconitine (Cmax = 6.82±3.1) and ACON (Cmax = 4.62±2.2). Moreover dose of GMT revealed 10 times safer than ACON. Overall processed ACON not produced any sign of toxicity at a dose dependent manner.