Hemoglobin Distribution Research Articles

Integrated deep learning approach for generating cross-polarized images and analyzing skin melanin and hemoglobin distributions.

Cross-polarized images are beneficial for skin pigment analysis due to the enhanced visualization of melanin and hemoglobin regions. However, the required imaging equipment can be bulky and optically complex. Additionally, preparing ground truths for training pigment analysis models is labor-intensive. This study aims to introduce an integrated approach for generating cross-polarized images and creating skin melanin and hemoglobin maps without the need for ground truth preparation for pigment distributions. We propose a two-component approach: a cross-polarized image generation module and a skin analysis module. Three generative adversarial networks (CycleGAN, pix2pix, and pix2pixHD) are compared for creating cross-polarized images. The regression analysis network for skin analysis is trained with theoretically reconstructed ground truths based on the optical properties of pigments. The methodology is evaluated using the VISIA VAESTRO clinical system. The cross-polarized image generation module achieved a peak signal-to-noise ratio of 35.514dB. The skin analysis module demonstrated correlation coefficients of 0.942 for hemoglobin and 0.922 for melanin. The integrated approach yielded correlation coefficients of 0.923 for hemoglobin and 0.897 for melanin, respectively. The proposed approach achieved a reasonable correlation with the professional system using actually captured images, offering a promising alternative to existing professional equipment without the need for additional optical instruments or extensive ground truth preparation.

Donor Parameters and Platelet Yield during Plateletpheresis: A Cross-sectional Prospective Study

Abstract Background: Platelet transfusion can be life-saving in bleeding patients with thrombocytopenia or reduced platelet function. Single donor platelets (SDP) unit use is preferred due to the various advantages like reduction in transfusion-transmitted diseases and transfusion reactions. The quality of SDP is determined by platelet yield. Therefore, we conducted this study to assess the donor parameters affecting platelet yield during plateletpheresis. Materials and Methods: This cross-sectional prospective study included 160 single-donor platelet apheresis procedures done for 1 year. The pre-donation platelet count of the donor was set to 250 × 109/L to get double-dose platelet. Plateletpheresis was performed using Trima Accel single-needle separator apheresis machine. The demographic and hematologic parameters of donors were correlated with their platelet yield. Data obtained were tabulated using version 20 of the Statistical Package for the Social Sciences (SPSS). A relationship between pre-donation donor variables and platelet yield was studied using the Pearson correlation coefficient (r). P < 0.05 was considered statistically significant. Results: There was a significant positive correlation between platelet yield and body mass index (BMI) (r = 1710 and P = 0.0304), total leukocyte count (TLC) (r = 0.2220 and P = 0.0048), and platelet count (r = 0.8880 and P < 0.0001). The mean platelet volume (MPV) showed a negative correlation with platelet yield (r = −0.1910 and P = 0.0156). Age, hemoglobin, hematocrit, and platelet distribution width showed no significant correlation with the platelet yield. Conclusion: Donor parameters such as pre-donation platelet count, BMI, TLC, and MPV need to be considered while recruiting the donors for the SDP procedure for better yield of platelets.

Optimal cut-off values and diagnostic significance of clinical laboratory indicators in newly diagnosed multiple myeloma

ObjectiveThis study aims to identify clinical laboratory parameters for the diagnosis of newly diagnosed multiple myeloma (NDMM), establish optimal cutoffs for early screening, and develop a diagnostic model for precise diagnosis.MethodsThe study conducted a retrospective analysis of 279 NDMM patients and 553 healthy subjects at Zhejiang Province People’s Hospital between January 2008 and June 2023. Multifactor LR was employed to explore clinical laboratory indicators with diagnostic value for NDMM, determine optimal cutoff values and contract a diagnostic model. The diagnostic efficacy and clinical utility were evaluated using receiver operating characteristic curves (ROC), sensitivity, specificity, and other indicators.ResultsMultifactor analysis revealed that hemoglobin (Hb), albumin (Alb), and platelet distribution width (PDW) were significant diagnostic factors for NDMM. Optimal cutoff values for Hb, Alb, and PDW in MM diagnosis were determined, and the results showed a significant increase in the probability of NDMM diagnosis when Alb was below 39.3 g/L, Hb was below 11.6 g/dL, and PDW was below 14.1 fL. The diagnostic model constructed from the development cohort demonstrated a high area under the ROC curve of 0.960 (95% CI 0.942–0.978) and exhibited good sensitivity (0.860), specificity (0.957). The area under the curve (AUC) value of the diagnostic model in the external validation cohort was 0.979, confirming its good diagnostic efficacy and generalization.ConclusionsThe optimal cutoff values for Hb, Alb, and PDW and the diagnostic model designed in the study provided good accuracy and sensitivity for the initial screening and diagnosis of NDMM.

Relationship of hemoglobin levels and distribution and severity of gingival melanin pigmentation: an exploratory cross-sectional study.

Relationship of hemoglobin levels and distribution and severity of gingival melanin pigmentation: an exploratory cross-sectional study.

Using spatial frequency domain imaging to monitor a skin biopsy wound: a pilot study.

Surgical wound infection is a global postoperative issue adding a significant clinical burden and increasing healthcare costs. Early detection and subsequent diagnosis of infection is vital for accurate, early, and effective treatments. In this paper, we report a pilot study exploring spatial frequency domain imaging (SFDI) to monitor, in-vivo, a biopsy wound in human skin. The reduced scattering coefficient, , absorption coefficient, and the oxygen saturation, StO 2, were measured using a SFDI system at 617 and 850 nm. We found the was better capable of monitoring structural changes, possible pus within the wound, re-epithelialization, and collagen fiber remodeling, than with the eye alone. The map is capable of revealing the total hemoglobin distribution in the wound area but was limited in some regions due to the scab covering. This case study indicates SFDI's potential for monitoring and quantifying the process of surgical wound healing and infection.

Ultrasound-guided photoacoustic (US-PA) tomography of the breast: Biochemical differentiation using intrinsic tissue markers—lipids, collagen and hemoglobin with histopathologic correlation

In this pilot study, we investigated the utility of handheld ultrasound-guided photoacoustic (US-PA) imaging probe for analyzing ex-vivo breast specimens obtained from female patients who underwent breast-conserving surgery (BCS). We aimed to assess the potential of US-PA in detecting biochemical markers such as collagen, lipids, and hemoglobin, and compare these findings with routine imaging modalities (mammography, ultrasound) and histopathology results, particularly across various breast densities. Twelve ex-vivo breast specimens were obtained from female patients with a mean age of 59.7 ± 9.5 years who underwent BCS. The tissues were illuminated using handheld US-PA probe between 700 and 1100 nm across all margins and analyzed for collagen, lipids, and hemoglobin distribution. The obtained results were compared with routine imaging and histopathological assessments. Our findings revealed that lipid intensity and distribution decreased with increasing breast density, while collagen exhibited an opposite trend. These observations were consistent with routine imaging and histopathological analyses. Moreover, collagen intensity significantly differed (P < 0.001) between cancerous and normal breast tissue, indicating its potential as an additional biomarker for risk stratification across various breast conditions. The study results suggest that a combined assessment of PA biochemical information, such as collagen and lipid content, superimposed on grey-scale ultrasound findings could aid in distinguishing between normal and malignant breast conditions, as well as assist in BCS margin assessment. This underscores the potential of US-PA imaging as a valuable tool for enhancing breast cancer diagnosis and management, offering complementary information to existing imaging modalities and histopathology.

Spectrum-based deep learning framework for dermatological pigment analysis and simulation

Background:Deep learning in dermatology presents promising tools for automated diagnosis but faces challenges, including labor-intensive ground truth preparation and a primary focus on visually identifiable features. Spectrum-based approaches offer professional-level information like pigment distribution maps, but encounter practical limitations such as complex system requirements. Methods:This study introduces a spectrum-based framework for training a deep learning model to generate melanin and hemoglobin distribution maps from skin images. This approach eliminates the need for manually prepared ground truth by synthesizing output maps into skin images for regression analysis. The framework is applied to acquire spectral data, create pigment distribution maps, and simulate pigment variations. Results:Our model generated reflectance spectra and spectral images that accurately reflect pigment absorption properties, outperforming spectral upsampling methods. It produced pigment distribution maps with correlation coefficients of 0.913 for melanin and 0.941 for hemoglobin compared to the VISIA system. Additionally, the model’s simulated images of pigment variations exhibited a proportional correlation with adjustments made to pigment levels. These evaluations are based on pigment absorption properties, the Individual Typology Angle (ITA), and pigment indices. Conclusion:The model produces pigment distribution maps comparable to those from specialized clinical equipment and simulated images with numerically adjusted pigment variations. This approach demonstrates significant promise for developing professional-level diagnostic tools for future clinical applications.

Hemoglobin Concentration as an Indicator of Skin Radiation Damage During Radiation Therapy Treatments

Acute radiation dermatitis (ARD) is the most common side effect reported by patients undergoing radiation therapy (RT). Currently, the assessment of the severity of the reaction is based on the visual assessment of the skin, which is a subjective method, depending on many factors. The main aim of this study was to investigate the usefulness of hyperspectral imaging (HSI) in the assessment of ARD and find physiological factors that could be correlated with ARD. In this clinical pilot trial, weekly acquisitions of hyperspectral camera images of irradiated skin were performed for 5 weeks of RT and at the posttreatment follow-up visit which took place 30 to 40 days after the last fraction of RT. At the same time, the severity of radiodermatitis was assessed based on the criteria of the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE). The content and concentration of chromophores in irradiated skin were quantitatively determined using a hyperspectral camera. The use of HSI supported by image analysis and processing methods allowed for the determination of the content and distribution of hemoglobin and melanin in the irradiated skin. It was found that the hemoglobin concentration is correlated with the subjective assessment made according to the CTCAE protocol. HSI is a sensitive and specific method of analyzing the concentration of chromophores in the skin, including hemoglobin. A clear correlation was found between hemoglobin concentration and CTCAE v.5 scale because of which HSI can be considered as an objective method of skin assessment during RT.

#1275 Post-transplant renal anaemia: a call to action from a national study in routine clinical practice

Abstract Background and Aims Post-transplant anaemia (PTA) is common, frequently unnoticed and carries associated risks. Current guidelines consider the same treatment recommendations and goals for these patients as for chronic kidney disease-non dialysis (CKD-NDD). Previous reports demonstrated low awareness and management that could improve. Aims: To describe current anaemia management, goals, and adherence to guidelines in a representative sample of kidney transplant (KT) recipients. Method Retrospective nationwide multicentre study including patients from 8 KT hospitals. Nephrologists collected demographics, comorbidities, KT data and immunosuppressive therapy and data related to anaemia management (laboratory values, previously prescribed treatments, and subsequent adjustments) from electronic medical records. We classified as early anaemia that within the first 6 months. The European statement on KDIGO guidelines was the reference for definitions, drug prescriptions and targets. Results We included 297 recipients with PTA aged 62.8 y (SD 13.6) and 60% male. They had received a graft from donors after cardiac death or brain death) (61.6%. 31.1% respectively) a median of 2.5 years [0.5-8.7] before. A total of 158 patients were on treatment with erythropoietin stimulating agents (ESAs) and the distribution of haemoglobin (Hb) and iron are summarized in Table 1. Among 110 patients on ESA treatment but without iron prescription, 44 had an indication to receive iron and 30 of them had absolute iron deficiency (ID). Only 39/158 patients exceeded the ESA resistance index (ERI) limit, and this condition was more frequent in early PTA (26.1 vs 9.2%). Absolute or functional ID accounted for the majority of ESA resistance (28.2 vs 17.1; p &amp;lt; 0.001). Conclusion Hemoglobin levels in these patients are within the upper KDIGO. Iron therapy continues to be underused (especially intravenous), while iron deficiency and prior events explain most of ESA hyporesponsiveness. We identify missed opportunities for accurate prescription targeting and adherence to guidelines.

A Prediction Nomogram for No-Reflow in Acute Myocardial Infarction Patients after Primary Percutaneous Coronary Intervention.

The coronary no-reflow (NR) phenomenon is an independent predictor of major adverse cardiac events (MACEs). This study aimed to establish a clinical and comprehensive nomogram for predicting NR in acute myocardial infarction (AMI) patients after primary percutaneous coronary intervention (pPCI). The multivariable logistic regression analysis was performed to determine the NR-related factors. A nomogram was established via several clinical and biochemical factors, and the performance was evaluated via discrimination, calibration, and clinical factors. The study consisted of 3041 AMI patients after pPCI, including 2129 patients in the training set (70%) and 912 patients in the validation set (30%). The NR event was 238 in the training set and 87 in the validation set. The level of N-terminal prohormone B-type natriuretic peptide (NT-proBNP), basophil count (BASO), neutrophil count (NEUBC), D-dimer, hemoglobin (Hb), and red blood cell distribution width (RDW.CV) in NR patients showed statistically significant differences. In the training set, the C-index was 0.712, 95% CI 0.677 to 0.748. In the validation set, the C-index was 0.663, 95% CI 0.604 to 0.722. A nomogram that may predict NR in AMI patients undergoing pPCI was established and validated. We hope this nomogram can be used for NR risk assessment and clinical decision-making and significantly prevent potentially impaired reperfusion associated with NR.

Aquasomes: an updated review

Aquasomes are circular particles that serve as nano particulate carrier systems, consisting of a solid phase nanocrystalline core coated in an oligomeric film. These three-layered self-assembled structures, ranging from 60 to 300 nanometers in size, allow direct or indirect absorption of biochemically active molecules. Aquasomes can be loaded with large amounts of agents through entropic, van der Waals, and ionic forces due to their size and active surface area. They display colloidal physical characteristics in an aqueous medium and are effective in distributing insulin, hemoglobin, serratiopeptidase, and poorly water-soluble medications.eramic nanoparticles, also known as aquasomes, are spherical particles that self-assemble into nanoparticulate carriers, resembling water bodies. These self-assembled structures are effective in the distribution of hemoglobin, insulin, and enzymes like serratiopeptidase. In this abstract, we will cover a review on Aquasomes.

Evaluation of biological selenium nanoparticles on growth performance, histopathology of vital organs and genotoxicity in Japanese quails (coturnix coturnix japonica)

Research on the effects of selenium nanoparticles (Se-NPs), particularly in Japanese quails, is lacking, especially regarding the potential for DNA damage. Therefore, this study aimed to investigate the impact of administering 0.2 and 0.4 mg/kg of Se-NPs on the growth performance, DNA integrity, and histopathological alterations of the liver, lung, kidney, and heart in quails. A total of 480 one-day-old Japanese quails were divided into three experimental groups as follows: Group 1 served as the control and received only basic feed, while Group 2 and 3 received 0.2 mg/kg and 0.4 mg/kg of Se-NPs via oral gavage. Our results suggested that, birds fed with Se-NPs at both levels significantly (p < .01) reduced feed intake, however, weight gain was significantly (p < .01) increased in quails supplemented with 0.2 mg/kg. Similarly, feed conversion ratio (FCR) was significantly (p < .01) reduced in group supplemented with 0.2 mg/kg Se-NPs. White blood cells increased significantly (P0.01) in 0.4 mg/kg while haemoglobin and red cell distribution width decreased (p < .01) in the same group. Both treatment regimens resulted in DNA damage and histopathological alterations; however, the adverse effects were more prominent in the group receiving the higher dose of 0.4 mg/kg. These findings indicate that the lower dose of 0.2 mg/kg may have beneficial effects on growth. However, the higher dose of 0.4 mg/kg not only negatively impacts growth but also leads to histopathological alterations in major organs of the body and DNA damage as well.

Classification and Explanation of Iron Deficiency Anemia from Complete Blood Count Data Using Machine Learning

Background: Currently, discriminating Iron Deficiency Anemia (IDA) from other anemia requires an expensive test (serum ferritin). Complete Blood Count (CBC) tests are less costly and more widely available. Machine learning models have not yet been applied to discriminating IDA but do well for similar tasks. Methods: We constructed multiple machine learning methods to classify IDA from CBC data using a US NHANES dataset of over 19,000 instances, calculating accuracy, precision, recall, and precision AUC (PR AUC). We validated the results using an unseen dataset from Kenya, using the same model. We calculated ranked feature importance to explain the global behavior of the model. Results: Our model classifies IDA with a PR AUC of 0.87 and recall/sensitivity of 0.98 and 0.89 for the original dataset and an unseen Kenya dataset, respectively. The explanations indicate that low blood level of hemoglobin, higher age, and higher Red Blood Cell distribution width were most critical. We also found that optimization made only minor changes to the explanations and that the features used remained consistent with professional practice. Conclusions: The overall high performance and consistency of the results suggest that the approach would be acceptable to health professionals and would support enhancements to current automated CBC analyzers.

Scientific validation of clinical visual scales and Antera 3D™ consistency with derived measurements in the assessment of infantile haemangioma after laser therapy

Laser therapy is a treatment for infantile haemangiomas. The efficacy of laser therapy for red lesions is determined by visual evaluation; however, this assessment is inaccurate and lacks objectivity. To scientifically validate the consistency between pre- and post-treatment visual assessment grades for infantile haemangioma treated with pulsed dye laser (PDL) and the values calculated from images obtained with Antera 3D™. This study involved 81 cases of infantile haemangiomas treated with PDL alone from 2012 to 2015 and with Antera 3D™ images of the lesions. Using images obtained before treatment and 4-6 weeks after the last treatment, the lesions were rated using a visual four-step scale. Ratings were categorised as Poor/Fair/Good/Excellent by the degree of improvement in the red colour tone. The red colour ratio was calculated using the haemoglobin distribution in the lesion and surrounding skin, and the improvement difference and improvement rate were then obtained. The correlation between the improvement difference and improvement rate, and visual evaluation was statistically analysed. No serious adverse effects were observed, with an average of 4.3 treatments per patient; 60.1% of the patients achieved Good/Excellent results. There were statistically significant differences in the post-treatment red colour ratio and improvement ratio in each category after visual evaluation classification. The improvement rate and the four visual grades were statistically correlated. This study confirmed the scientific validity of visual evaluation and the evaluation criteria calculated from Antera 3D™. This method could objectively determine treatment effectiveness.

First 24-Hour-Long Intensive Care Unit Testing of a Clinical-Scale Microfluidic Oxygenator in Swine: A Safety and Feasibility Study.

Microfluidic membrane oxygenators are designed to mimic branching vasculature of the native lung during extracorporeal lung support. To date, scaling of such devices to achieve clinically relevant blood flow and lung support has been a limitation. We evaluated a novel multilayer microfluidic blood oxygenator (BLOx) capable of supporting 750-800 ml/min blood flow versus a standard hollow fiber membrane oxygenator (HFMO) in vivo during veno-venous extracorporeal life support for 24 hours in anesthetized, mechanically ventilated uninjured swine (n = 3/group). The objective was to assess feasibility, safety, and biocompatibility. Circuits remained patent and operated with stable pressures throughout 24 hours. No group differences in vital signs or evidence of end-organ damage occurred. No change in plasma free hemoglobin and von Willebrand factor multimer size distribution were observed. Platelet count decreased in BLOx at 6 hours (37% dec, P = 0.03), but not in HFMO; however, thrombin generation potential was elevated in HFMO (596 ± 81 nM·min) versus BLOx (323 ± 39 nM·min) at 24 hours ( P = 0.04). Other coagulation and inflammatory mediator results were unremarkable. BLOx required higher mechanical ventilator settings and showed lower gas transfer efficiency versus HFMO, but the stable device performance indicates that this technology is ready for further performance scaling and testing in lung injury models and during longer use conditions.

Prevalence of Anemia and Hemoglobin Distribution Based on Large-scale Occupational Health Examination Data.

Objective To calculate the prevalence of anemia based on sex and age using large-scale occupational health examination data, confirm the Hb) distribution in the elderly, and examine the standard for screening for anemia in Japan. Methods Using existing large-scale occupational health examination data of patients who underwent health examinations between April 2015 and March 2022, we calculated the prevalence of anemia based on sex and age. Patients We included 416,366 patients aged 20-89 years who underwent health checkups at health checkup facilities in Japan. Results Of the patients, 53.5% were men. The proportion of previously anemic individuals was 3.2% in men and 19.7% in women, with Hb levels (mean ± SD) of 15.1±1.1 g/dL in men and 13.1±1.2 g/dL in women. The prevalence of anemia showed a monotonic increase with age in men and a bimodal distribution, peaking in women in their 40s and 70s. Among women in their 20s-40s, 17.9% had anemia, and 60% were newly diagnosed. Furthermore, the mean -2SD of Hb in the elderly men (>65 years) was 12.0 g/dL, larger than the current standard (11.0 g/dL). Conclusion It is imperative to consider the possibility of anemia in young women during health examinations and other screening opportunities, regardless of their history of anemia. In addition, elderly men with Hb levels <12 g/dL should be cautioned about the development of anemic symptoms and the progression of Hb decline.

User verification of Abbott Alinity HQ hematology analyzer

Abstract Objectives This study aims to evaluate the performance characteristics of the Alinity HQ hematology analyzer in a routine laboratory setting. Methods In the study, precision (short-term and long-term precision), accuracy (method comparison with Abbott Cell Dyn Ruby and estimation of bias), confirmation of a background (Limit of Blank, LoB), and carry-over were used to evaluate the performance of Alinity HQ as recommended by ICSH, CLSI guidelines EP15-A3, EP09, EP17A2, and H26-A2. Acceptance criteria were based on manufacturer technical specifications and the EFLM Biological Variation Database. Results According to the short-term precision results, except for mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC), all measurements exhibited coefficient variations (CV) lower than their verification limits. Basophil, eosinophil, and monocyte counts, as well as mean corpuscular hemoglobin (MCH), MCHC, and red cell distribution width standard deviation (RDW-SD), did not meet the allowable imprecision criteria for the long-term precision study. The estimated bias for all analytes was within verification limits. However, the method comparison study showed concentration-dependent variations for MCHC, MCH, and mean platelet volume (MPV) parameters. Furthermore, the correlation of parameters between Alinity HQ and Cell Dyn Ruby ranged from 0.46 to 1.00. The LoB and carry-over studies demonstrated satisfactory performance for the Alinity HQ analyzer. Conclusions Although some parameters had higher CVs than expected and concentration-dependent bias, the overall analytical performance of Alinity HQ was found to be satisfactory. Alinity HQ is an accurate, highly precise analyzer with good analytical performance, suitable for high-volume laboratories.

Evaluating Sex-Based Hemoglobin Reference Intervals Using Strict Definitions of Health

Introduction: Hemoglobin reference intervals (RIs) are developed by laboratory assay manufacturers, and laboratories establish a RI using 120 “normal” samples when first implementing a new assay. Many institutions report different hemoglobin RIs for females and males with wide variation between institutions. Re-evaluation of hemoglobin RIs is warranted to ensure that optimal health for all patients is accurately represented. Using National Health and Nutrition Examination Survey (NHANES) data, we evaluated the impact of excluding adults with chronic disease, iron deficiency (ID), inflammation, and red blood cell (RBC) disorders on hemoglobin lower limit of normal (LLN). Methods: Adults &amp;gt; 20 years in the NHANES from 2001-2006 and 2017-2020 were included. Demographic characteristics, self-reported medical history and medication use, and laboratory parameters were extracted. We generated hemoglobin distributions weighted to represent the population of the USA. From these distributions, 2.5%, 50%, and 97.5% values were individually and compositely evaluated when excluding chronic disease (defined as the healthy cohort), ID, inflammation, and RBC disorders. The healthy cohort excluded patients with a medical history of anemia, malignancy, current pregnancy, smoking, or liver, lung, kidney, or heart disease. Iron deficiency was defined as ferritin &amp;lt; 50 ng/mL, transferrin saturation (Tsat)&amp;lt;20%, or total iron binding capacity (TIBC) &amp;gt; 400 μg/dL. Inflammation was defined as ferritin&amp;gt;300 ng/mL, hs-CRP&amp;gt;1 mg/L, albumin&amp;lt;3.5 g/dL, white blood cells&amp;gt;10 K/uL, or TIBC&amp;lt;200 μg/dL. RBC disorders were defined as history of blood transfusion, MCV &amp;lt;80 or &amp;gt;100, Tsat&amp;gt;55%, MCHC &amp;gt;36, Mentzer index&amp;lt;13, or hydroxyurea or iron chelator use. Finally, we conducted several sensitivity analyses that assessed degree of ID at different levels of ferritin ranging from &amp;lt; 15 ng/mL to &amp;lt; 100 ng/mL. All analyses were conducted in R using the survey package. Results: There were 10,338 individuals in the total cohort, 5757 in the healthy cohort, and 1609 in the cohort with all exclusions applied. Among females, the hemoglobin LLN was 10.7g/dL in the total cohort, 10.6g/dL in the healthy cohort, 10.4g/dL in the cohort excluding inflammation, 11.7g/dL in the cohort excluding RBC disorders, 12.2g/dL in the cohort excluding ID, and 12.3g/dL in the cohort with all exclusions applied. Among males, the hemoglobin LLN was 12.5g/dL in the total cohort, 12.9g/dL in the healthy cohort, 12.9g/dL in the cohort excluding inflammation, 13.2g/dL in the cohort excluding RBC disorders, 13.0g/dL in the cohort excluding ID, and 13.3g/dL in the cohort with all exclusions applied. The difference between male and female hemoglobin LLN narrowed from 2.3g/dL (12.9g/dL vs 10.6g/dL) in the healthy cohort to 1g/dL (13.3g/dL vs 12.3g/dL) in the cohort with all exclusions applied. For males, the largest difference in hemoglobin LLN was seen when RBC disorders were excluded (12.9g/dL to 13.2g/dL; 0.3g/dL difference), and for females the greatest difference was seen when ID was excluded (10.6g/dL to 12.2g/dL; 1.6g/dL difference). Hemoglobin LLN by menopausal status for females and by age for males is shown in Figure 1. Pre-menopausal females had a significant increase in hemoglobin LLN when ID alone was excluded (10.3g/dL to 12.3g/dL), but this degree of change was not observed in healthy post-menopausal females or males. Degree of ID by ferritin level by sex and menopausal status or age is shown in Figure 2. Using a threshold of ferritin &amp;lt;30 ng/mL, 38.9% of pre-menopausal females were iron deficient compared with 10.3% of post-menopausal females and 3.5% of males. Discussion: Applying strict criteria for health and specifically excluding inflammation, RBC disorders, and ID resulted in higher hemoglobin LLN for both sexes and narrowed the difference in LLN between males and females. Pre-menopausal females had the most significant change in hemoglobin LLN from the healthy cohort to the cohort with all exclusions applied, and this was predominately driven by a very high prevalence of ID. ID is a pandemic that disproportionally impacts females of reproductive age. These findings emphasize the burden of ID and its systemic consequences, including normalization of anemia. It is imperative that institutions rigorously and thoughtfully define their hemoglobin RIs by ensuring that strict definitions of health are applied with an emphasis on excluding those with ID.

Assessing Real-Time Sickling Kinetics in Individual Cells from Erythrocyte Populations of Subjects with Different HbA, HbS and HbF Percentages

INTRODUCTION: Polymerization of deoxygenated sickle hemoglobin (HbS) leads to erythrocyte sickling. Treatment in sickle cell disease (SCD) aims to reduce the risks of red blood cell (RBC) sickling and associated complications including, but not limited to vaso-occlusive crises (VOC). There is substantial promise in developing therapies targeting HbS polymerization that consequently decrease RBC sickling, a fundamental pathophysiological driver of SCD. Nonetheless, there are limited options available for reliable diagnostic tools for the assessment of disease status and therapeutic outcomes. A robust and easy-to-use system to assess population-scale sickling kinetics and to monitor responses to Hb-modifying therapies in clinical trials for the clinical management of patients may be beneficial. We have developed a dynamic sickling assay (DSA) that uses an enzymatic oxygen scavenging system to provide tight control over the rate and depth of induced-hypoxia. DSA is able to differentiate samples based on endogenous Hb expression and can be used to monitor sickling kinetics pre- and post HbS-modifying therapies, including hematopoietic stem cell transplantation (HSCT). METHODS: SCD and sickle cell trait (SCT) subjects were recruited under the RBC Health Initiative IRB protocol number FF-RBC-003. Four hematopoietic stem cell transplant (HSCT) SCD subjects were enrolled in NIH haploidentical HSCT protocol 17-H-0069. Diluted blood samples were supplemented with protocatechuic acid (PCA), followed by protocatechuate 3,4-dioxygenase (PCD) enzyme inducing hypoxia at a predetermined rate. The sample was then injected into a microfluidic chamber, and resulting RBC morphological changes were observed and captured with time-lapse photography. Image analysis identified and quantified RBC using an AI-trained SICKLE image analysis software. HbAS (n=3), HbSS with HbA (post-transfusion, n=3) and HbSS samples containing 3.1 to 34.5% HbF (n=9) were processed with DSA to assess the effects of hemoglobin distribution on sickling kinetics.Pre- and post-HSCT samples were run to ascertain the effect on sickling kinetics at baseline, 3M, 6M and 12M post-HSCT. Sickling profiles were constructed enabling a comprehensive assessment of RBC sickling and treatment outcomes. The reported parameters include: mPOS@5% (time to reach 5% induced sickling, min), mPOS@50% (time to reach 50% maximum induced sickling,min), rate of sickling (the maximum sickling rate, %/min), maximum induced sickling (the highest induced sickling percentage, %), AUC at 10min (area under the curve@10min of DSA, %∙minute) RESULTS: DSA inter-run CVs are 6.9% for mPOS@5%, 3.8% for mPOS@50%, 2.7% for max sickling, 4.2% for AUC and 10.8% for the rate of sickling. Statistically significant correlations are observed between %HbS and rate of sickling, max sickling, mPOS@5%, and AUC at 10min. As percentages of Hb increased in transfused SCD patient samples, there were noticeable correlations between the delay in mPOS@5% and decreased rate of sickling, maximum sickling, and AUC10. Similarly, as HbA percentages increased in SCT samples, a decrease in AUC10 and max sickling were observed. Transfused and SCT samples did not show statistical significance due to sample size limitations. However, there was a strong correlation in delay of mPOS@5% and mPOS@50%, as well as a decrease in the rate of sickling and AUC10 with increasing percentages of HbF in samples (Table 1). Comparing pre-HSCT (BL) sample sickling kinetics to 3, 6 and 12 month post-HSCT samples showed decreases in the rate of sickling (from 44.4 to 0.6%), maximum sickling (from 45-23%), decreases in AUC and delays in mPOS (Table 2). CONCLUSIONS: This study found significant linear relationships between %HbS and sickling parameters.As HbA percentage increases in transfused SCD and SCT samples, improvements in sickling parameters are observed. There is a strong correlation between increased HbF percentage and improved DSA parameters. Comparative data analysis from patients pre- and post-HSCT also show improvement in sickling parameters. Overall, DSA provides a simple, robust method for assessing responses to Hb differences and monitoring SCD therapies such as gene-editing.

Characteristics of hemoglobin distributions in preschool children and non-pregnant women of reproductive age and their implications for establishing quality control criteria for hemoglobin data in field surveys: evidence from 483 surveys conducted in refugee settings worldwide

BackgroundCurrently, there is a lack of clear guidance on hemoglobin (Hb) data quality parameters and plausible flagging ranges for population-representative surveys. There is a need to determine which properties of Hb data indicate lower data quality and increased measurement error and which represent intrinsic statistical properties of Hb distributions rather than quality problems.MethodsWe explored statistical characteristics of Hb distributions and plausible exclusion ranges in population-representative surveys of non-pregnant women of reproductive age (WRA) (15–49 years, n = 401 surveys) and children (6–59 months, n = 461 surveys) conducted in refugee settings by the United Nations High Commissioner for Refugees (UNHCR). Hb distribution characteristics [standard deviation (SD), skewness and kurtosis] were compared to those from Demographic and Health Surveys (DHS).ResultsOverall, 0.08% of child and 0.14% of WRA Hb values were outside of the previously proposed 4.0–18.0 g/dL plausible range. Surveys conducted in Uganda tended to have unusually high SD compared with surveys from other settings, possibly an indication of problematic measurement quality. We therefore used summary results on SD, skewness and kurtosis excluding surveys from Uganda when comparing with DHS results or proposing plausible ranges. Both WRA and child Hb distributions tended to be left-skewed and had excess positive kurtosis. Mean survey-level SD was greater, mean skewness more negative, and mean kurtosis more positive in WRA surveys compared to child surveys. All these findings were broadly similar to those from DHS surveys. Mean SD in DHS surveys was higher than that in our data for both children (1.48 vs. 1.34) and WRA (1.58 vs. 1.43).ConclusionsWe observed several statistical characteristics of Hb distributions that may not necessarily be indicative of data quality problems and bear strong similarities with the characteristics found in DHS surveys. Hb distributions tended to be negatively skewed and positively kurtotic, and SD in many surveys exceeded 1.5 (previously proposed upper plausible range). Based on our empirical evidence, surveys with skewness above + 0.2 and kurtosis below -0.5 or Hb SD outside the range of 1.1–1.55 g/dL for children (6–59 mo) or 1.1–1.65 g/dL for non-pregnant WRA (15–49 y) may require further quality investigation.