Genetically influenced tobacco and alcohol use behaviors impact erythroid trait variation.

Genome wide association studies (GWAS) have associated thousands of loci with quantitative human blood trait variation. Loci and related genes that impact blood trait variation may regulate blood cell-intrinsic biological processes, or alternatively impact blood cell development and function via systemic factors. Clinical observations have linked tobacco or alcohol use with altered blood traits, but these trait relationships have not been systematically explored at the genetic level. Applying a Mendelian randomization (MR) framework to GWAS summary statistics, we explore relationships between smoking and drinking behaviors with 15 quantitative blood traits. We find that the effects of smoking and drinking are confined to red blood cell traits. An instrumental variable (IV) comprised of 113 single nucleotide polymorphisms (SNPs) associated with smoking initiation is associated with decreased hemoglobin (HGB: Effect = -0.07 standard deviation units [95% confidence interval = -0.03 to -0.10 SD units], P = 1x10-4), hematocrit (HCT: Effect = -0.06 [-0.03 - -0.09] SD units, P = 4x10-4), and red blood cell count (RBC: Effect = -0.05 [-0.02 - -0.09] SD units, P = 5x10-3) without impacting platelet count (P = 0.9) or white blood cell count (P = 0.6). Similarly, an IV associated with an increased number of alcoholic drinks consumed per week is associated with decreased HGB (Effect = -0.22 [-0.42 - -0.02] SD units, P = 3x10-2) and RBC (Effect = -0.27 [-0.51 - -0.03] SD units, P = 3x10-2). Using multivariable MR and causal mediation analyses, we find that an increased genetic predisposition to smoking initiation is associated with increased alcohol intake, and that alcohol use mediates the genetic effect of smoking initiation on red blood cell traits. These findings demonstrate a novel role for genetically influenced behaviors on human blood traits, revealing opportunities to dissect related pathways and mechanisms that influence hematopoiesis and blood cell biology.

Change in Tacrolimus Concentration Measured in Whole Blood Correlates With Changes in Red Blood Cell Parameters After Red Blood Cell Transfusion in Kidney Transplant Recipients.

BACKGROUND: Tacrolimus (TAC) is a narrow therapeutic range drug that requires therapeutic drug monitoring. TAC concentration is measured using whole blood owing to its high red blood cell (RBC) transfer rate of 95%. The distribution and whole-blood TAC concentration may be affected by the transfusion of red cell concentrates (RCCs); however, this has not been studied in kidney transplant recipients (KTR). Therefore, we investigated the relationship between changes in whole-blood TAC concentration and RBC parameters before and after RCC transfusion in KTR. METHODS: Fifteen KTR who received TAC and RCC transfusions were enrolled. The change rates of RBC parameters (RBC count, hemoglobin [Hgb], hematocrit [Hct]), and TAC concentration/dose before and after transfusion were calculated. The correlation between each RBC parameter and the TAC rate was evaluated. RESULTS: The TAC concentration and rate increased after RCC transfusion. Moreover, the TAC rate showed a significant and strong correlation with RBC count, Hgb, and Hct, with RBC count showing the highest correlation coefficient (r = 0.811, 0.766, and 0.764, respectively; p < .01). Serum creatinine and potassium levels remained stable, suggesting the absence of typical adverse effects associated with TAC, such as acute kidney injury or hyperkalemia. CONCLUSION: Changes in whole-blood TAC concentration and RBC parameters were correlated, and whole-blood TAC concentration increased after RCC transfusion. Therefore, the TAC dose should be adjusted accordingly.

Preoperative blood-based nutritional biomarkers as significant prognostic factors after intravesical BCG therapy in patients with non-muscle-invasive bladder cancer.

The aim of this study was to investigate the prognostic role of blood-based nutritional biomarkers, including red blood cell (RBC count), hemoglobin (Hb), total protein (TP), albumin, the serum albumin to globulin ratio (AGR) and the prognostic nutritional index (PNI) in patients who underwent intravesical treatment for non-muscle invasive bladder cancer (NMIBC). A total of 501 NMIBC patients who received intravesical Bacillus Calmette-Guerin (BCG) treatment following transurethral resection of bladder tumor (TURBT) were included. The optimal cutoff values for these nutrition-based indicators were determined using receiver operating characteristic curve analysis. We observed a significantly higher recurrence-free survival (RFS) rate in patients with elevated levels of RBC count, Hb, TP, and albumin. Cox univariate and multivariate Cox regression analyses demonstrated that serum albumin (P = 0.002, HR = 0.51, 95%CI: 0.33-0.78), RBC count (P = 0.002, HR = 0.50, 95%CI: 0.32-0.77), TP (P = 0.028, HR = 0.62, 95%CI: 0.41-0.95), Hb (P = 0.004, HR = 0.53, 95%CI: 0.33-0.84), AGR (P = 0.003, HR = 0.46, 95%CI: 0.27-0.76) and PNI (P = 0.019, HR = 0.56, 95%CI: 0.35-0.91) were significant independent factors predicting RFS. These cost-effective and convenient blood-based nutritional biomarkers have the potential to serve as valuable prognostic indicators for predicting recurrence in NMIBC patients undergoing BCG-immunotherapy.

Morphological Characteristics of Colon Tumors in Mice with Different Tolerance to Hypoxia.

In adult male C57BL/6 mice with high (HR) and low (LR) resistance to hypoxia, morphological features of colon tumors and blood parameters were evaluated 70 days after intraperitoneal injection of azoxymethane and subsequent consumption of 3 cycles of dextran sulfate sodium. On macroscopic analysis, tumors were found in the distal colon in 35% (7 of 20 animals) of HR and 31% (4 of 13 animals) of LR animals. Microscopic analysis of the distal colon revealed tumors in 75% (15 of 20 animals) of HR and 69% (9 of 13 animals) of LR mice. The tumors were presented by areas of glandular intraepithelial neoplasia and adenocarcinomas; the incidence and the area of the tumors did not differ in groups of HR and LR mice. The number of neuroendocrine and goblet cells in the distal colon mucosa in the areas of tumors was similar in the compared groups. However, in both HR and LR mice of the experimental groups, the content of goblet cells in tumors was lower and the content of endocrine cells was higher than in the corresponding control groups. In the peripheral blood, the erythrocyte count and hemoglobin content decreased in HR and LR mice of the experimental groups; the relative number of monocytes increased only in HR mice and the absolute number of lymphocytes and monocytes decreased in LR mice. Thus, 70 days after azoxymethane administration and dextran sulfate sodium consumption, the tumors in mice were presented by glandular intraepithelial neoplasia and adenocarcinomas, and their incidence and area did not differ between animals with different tolerance to hypoxia.

Elevated mtDNA content in RBCs promotes oxidative stress may be responsible for faster senescence in men.

BACKGROUND: Both we and others have found that RBC counts are significantly lower in older compared to younger. However, when gender is factored in, a significant age-related decrease of RBC counts is observed only in men but not in women. METHODS: qPCR and confocal microscopy were used to detect the presence of mtDNA in RBCs. Flow cytometry and specific inhibitors were used to determine how RBCs uptake cf-mtDNA. The peripheral blood was collected from 202 young adults and 207 older adults and RBC and plasma were isolated. The levels of TLR9+RBCs and apoptotic RBCs after uptake of cf-mtDNA by RBCs were measured by flow cytometry. The kit detects changes in SOD and MDA levels after cf-mtDNA uptake by RBCs. Young RBCs (YR) and old RBCs (OR) from single individuals were separated by Percoll centrifugation. RESULTS: We found a significant decrease in RBC counts and a significant increase in the RDW with aging only in men. We also found that significantly elevated mtDNA content in RBCs was observed only in men during aging and was not found in women. Further studies demonstrated that RBCs could take up cf-mtDNA via TLR9, and the uptake of mtDNA might lead to a decrease in the RBC number and an increase in RDW due to an increase of oxidative stress. CONCLUSIONS: The RBC mtDNA content might be a potential marker of RBC aging and the elevated RBC mtDNA content might be the cause of faster senescence in males than females.

Associations of RBC counts and incidence of DVT in patients with spinal cord injury: a five year observational retrospective study.

BACKGROUND: The role of red blood cell (RBC) counts as potential independent risk factors for deep vein thrombosis (DVT) in patients with spinal cord injury (SCI) remains uncertain. This study aims to clarify the associations between RBC counts and DVT incidence among this population. METHODS: A retrospective analysis was performed on 576 patients with SCI admitted to the rehabilitation medicine department from January 1, 2017 to December 31, 2021. After exclusions, 319 patients were analyzed, among which 94 cases of DVT were identified. RESULTS: Mode of injury, D-dimer and anticoagulant therapy were significant covariates (P < 0.05). Age, fibrinogen, D-dimer, anticoagulant therapy and American Spinal Cord Injury Association impairment scale (AIS) grades were associated with RBC counts and DVT incidence (P < 0.05). Adjusting for these factors, a 1.00 × 10^12/L increase in RBC counts correlated with a 45% decrease in DVT incidence (P = 0.042), revealing a "U" shaped relationship with a pivot at 4.56 × 10^12/L (P < 0.05). CONCLUSION: RBC counts below 4.56 × 10^12/L serve as a protective factor against DVT, while counts above this threshold pose a risk. These findings could inform the development of DVT prevention strategies for patients with SCI, emphasizing the need for targeted monitoring and management of RBC counts.

Effect of Jianpi Shengxue Tablet on Iron Metabolism and Nutritional Status in Patients with Renal Anemia: A Prospective, Randomized, Open, Parallel Controlled and Multicenter Clinical Study.

OBJECTIVE: This study aimed to analyze the clinical efficacy of the Jianpi Shengxue tablet for treating renal anemia. METHODS: A total of 200 patients with renal anemia from December 2020 to December 2022 were enrolled and randomly divided into two groups. Patients in the control group were treated with polysaccharide-iron complex, and those in the experimental group were administered Jianpi Shengxue tablet. After 8 weeks of continuous treatment, the therapeutic outcomes regarding anemia were compared between the two groups. RESULTS: After treatment, the red blood cell (RBC) count, hematocrit (HCT), reticulocyte percentage (RET), ferritin (SF), serum iron (SI), transferrin saturation (TSAT), and serum albumin (ALB) all increased (P<0.01), and the clinical symptom score and total iron binding capacity decreased (P<0.01) in the experimental group. Moreover, the improvements in RBC, HCT, RET, SF, SI, TAST, ALB, and clinical symptoms (fatigue, anorexia, dull skin complexion, numbness of hands and feet) in the experimental group were significantly greater than those in the control group (P<0.05). The total effective rate for treating renal anemia was significantly higher in the experimental group than in the control group (P<0.01). CONCLUSION: The Jianpi Shengxue tablet demonstrates efficacy in treating renal anemia, leading to significant improvements in the laboratory examination results and clinical symptoms of patients with renal anemia.

Longitudinal hematological change in uncomplicated twin pregnancies: The white blood cell count decreases through pregnancy after the first trimester.

OBJECTIVE: Longitudinal hematological changes throughout twin pregnancies have not been reported. This study aimed to reveal longitudinal changes in hematological indices in twin pregnancies. MATERIALS AND METHODS: We conducted a retrospective chart review of hematological changes in uncomplicated twin pregnancies delivered at ≥37 weeks of gestation between 2010 and 2013 and randomly selected uncomplicated singletons during the same period. A complete blood count and hemogram were performed as blood examinations in the first trimester (9-13 weeks), late second trimester (22-27 weeks), mid-third trimester (33-35 weeks, only in twin pregnancies), and late third trimester (36-38 weeks). We evaluated inter-trimester differences in hematological indices and compared the values between twin and singleton pregnancies in each trimester. RESULTS: The final analysis group included 60 twin pregnancies and 63 singleton pregnancies. The white blood cell (WBC) count in twin pregnancies decreased throughout the pregnancy after the first trimester and became significantly lower than that in singletons in the late third trimester. The WBC count showed only a slight decrease in the third trimester in singleton pregnancies, whereas it showed a marked decrease throughout the pregnancy in twin pregnancies. The marked decrease in the total WBC count in twin pregnancies is mainly due to a decrease in neutrophils. The red blood cell count and hemoglobin and hematocrit values in twin pregnancies showed more marked decreases in the second trimester than in singletons. No decrease was observed after the second trimester of pregnancy. The platelet count decreased in the third trimester of twin pregnancies. CONCLUSION: We clarified the longitudinal hematological changes in twin pregnancies that showed augmentation of or differed from those of singleton pregnancies. It should be specifically mentioned that the WBC count markedly decreased through pregnancy after the first trimester, which is a characteristic change in twin pregnancies.

Correlation between erythrocyte parameters and iron status in cyclic Spanish Purebred mares.

The aim of this study was to evaluate the serum iron status and its relation to hematological indexes in cyclic mares. Blood samples were taken from 40 Spanish Purebred mares on days - 5, 0, + 5 and + 16 of their cycle. Concentration of transferrin (TRF) was significantly lower on day 0 than on days + 5 and + 16, transferrin saturation (TSAT) decreased significantly on days 0 and + 16 compared to day - 5, total iron-binding capacity (TIBC) on day + 16 was significantly higher than those on days - 5 and 0, and on day + 5 it was also significantly higher than that on day 0, unsaturated iron-binding capacity (UIBC) was reduced on day + 16 compared to days - 5 and 0, red blood cell (RBC) count on day + 16 was higher than that on days - 5 and 0 (p < 0.05), with no differences in the concentration of hemoglobin (HB) and packed cell volume (PCV). TRF and TIBC (r = 0.95), RBC and HB (r = 0.64), RBC and PCV (r = 0.78), and HB and PCV (r = 0.63) were positively and significantly correlated (P < 0.05). The estrous cycle in the Spanish Purebred mare is characterized by an increase in TRF and TIBC during the follicular phase and an increase in TSAT, UIBC and RBC in the luteal phase, without changes in other hematological parameters. The coordinated activity of these parameters guarantees an adequate iron (Fe) transfer and utilization during follicular development, ovulation, and the luteal period in the mare. Therefore, the estrous cycle must be considered in the evaluation of the mare's iron status, in light of significant changes observed both in early and at late luteal phases. The magnitude of these changes and the meaning to the physiology of the mares showed that in cyclic mares, hematological parameters and indicators of iron status evolve differently depending on the phase of the cycle, and their interpretation can help to veterinarians involved in equine practice.

An Introduction to the Complete Blood Count for Clinical Chemists: Red Blood Cells.

BACKGROUND: The most frequently ordered laboratory test worldwide is the complete blood count (CBC). CONTENT: In this primer, the red blood cell test components of the CBC are introduced, followed by a discussion of the laboratory evaluation of anemia and polycythemia. SUMMARY: As clinical chemists are increasingly tasked to direct laboratories outside of the traditional clinical chemistry sections such as hematology, expertise must be developed. This review article is a dedication to that effort.

Hematological Trends in Severe Burn Patients: A Comprehensive Study for Prognosis and Clinical Insights.

Severe burn injuries pose diagnostic challenges, contributing to increased fatality rates with delayed diagnoses. This study aims to identify early risk factors and understand their impact on clinical outcomes by examining hematological dynamics in severe burn cases. The focus includes age-related patterns, total body surface area (TBSA) affected by burns, hospital stay duration, and changes in hematological markers during burn injuries. An analytical cross-sectional study at the burn care center involved 135 participants hospitalized between January 2018 and December 2021. Demographic data and hematological markers were recorded, and statistical analysis was performed using IBM SPSS 25.0. Nonsurvivors exhibited a greater mean TBSA, shorter hospital stay, and an enhanced early immune response indicated by white blood cell count on the first day. Hematological markers, including hemoglobin, red cell count (RCC), and platelet count, showed dynamic patterns over the study period. Marginal variations in platelet counts and intriguing patterns in RCC suggested potential consequences like disseminated intravascular coagulation. The study provides crucial insights into hematological responses to severe burn injuries. Early identification of risk factors, particularly age-related patterns and immune responses, informs clinicians about predicting outcomes and guiding therapeutic interventions. Despite limitations, this work underscores the need for further multicenter research to comprehensively understand the complex relationships between burn injuries, hematological responses, and clinical outcomes.

The importance of schistocytes in a patient in VA-ECMO.

The presence of schistocytes can be responsible for spurious thrombocytosis and spuriously low red blood count (RBC). The hemoglobin concentration will be correct (as the method usually used, destroys the red cells and converts a substantial proportion of the hemoglobin to a stable pigment) but mean corpuscular hemoglobin (MCH) is falsely high. The platelets and RBC histograms of the full blood count analyzers play an important role in the identification of schistocytes and must be carefully analyzed before reporting the previously full blood count parameters. In patients in ECMO, where can be expected the presence of a small number of schistocytes, this evaluation is particularly important to avoid wrong clinical decisions.

Comparison Evaluation of Automated Nucleated Red Blood Cell Enumeration by Sysmex XN 1000 in Comparison With Microscopic Reference in Children Under 1 Year.

BACKGROUND: In newborns, elevated nucleated red blood cell (NRBC) levels can be associated with enhanced erythropoietic stress and might be predictive for adverse outcome. Also, the presence of NRBC in peripheral blood might lead to erroneous enumeration results of white blood cells in automated hematology analyzers. We aimed to assess the comparability of the Sysmex XN 1000 to manual slide reviews and correlation of NRBC with inflammation markers. METHODS: Specimens of 3397 children under 1 year were compared by automated and microscopic NRBC enumeration. Additionally, potential correlations between NRBC and age and inflammation markers were examined. RESULTS: Overall, there was good correlation (r = 0.97) between automated (range: 0%-3883%) and microscopic enumeration (range: 0%-3694%) of NRBC with high comparability up to a NRBC value of 200% and an increase in the variation between the two methods with increasing NRBC numbers. When 94 samples with ≤ 200% NRBC and ≥ 30% divergence between methods were separately reanalyzed with respect to overlapping cell populations in their scattergrams, Sysmex would have generated unrecognized incorrect automated results in 47 samples, corresponding to 1.4% of total study samples. NRBC counts were negatively correlated to age, but not to inflammation markers. CONCLUSION: Sysmex XN 1000 is highly precise in the enumeration of NRBC in children under 1 year up to counts of 200% and might replace time-intense manual counting in routine diagnostics. In the setting of neonatal and intensive care diagnostics, microscopic control and supervision of scattergrams are highly recommended for any automated NRBC enumeration processes.

Correlations between the degree of infection by wild strain of Toxoplasma gondii in vitro and porcine hematological parameters.

The apicomplexa Toxoplasma gondii is capable of actively proliferating in numerous types of nucleated cells, and therefore has a high potential for dissemination and resistance. Thus, the present work aimed to correlate the inoculum concentrations and amount of post-infection parasites with porcine hematological parameters (including biochemistry) through in vitro culture. Porcine blood was incubated with different concentrations of parasites (1.2 × 107, 6/3/1.5 × 106 cells/mL), then the concentrations of red blood cells (RBC) and their morphology, total and differential leukocytes, and free peptides were evaluated. In addition, eight different blood samples analyzed before inoculation, where subsequent multivariate analysis was applied to correlate different variables with trophozoite concentration. The results showed no significant variation (p < 0.05) in the relative levels of free peptides, or the relative percentage of RBC at all the parasite concentrations tested. However, the normalized percentages of leukocytes and neutrophils showed a significant reduction, while those of lymphocytes, eosinophils and monocytes showed the opposite behavior. Semi-automatic processing of images exhibited significant microcytosis and hypochromia. The multivariate analysis revealed a positive correlation between the amount number of protozoa (AP) and the variables: "Red cells" and "Neutrophils", an indifference between the AP and the content of free peptides, and the concentration of monocytes in the samples; and a negative correlation for AP and the percentages of lymphocytes and eosinophils. Our results suggest that specific changes in hematological parameters may be associated with different degrees of parasitemia, demanding a thorough diagnostic process and adequate treatment.

Comparison of hematologic variables among Warmbloods, Thoroughbreds, and Western stock horse breeds.

BACKGROUND: Hematology is a diagnostic tool used to evaluate the health status of horses. However, breed differences are often not considered. OBJECTIVES: The objective was to compare complete blood count variables among Warmbloods, Thoroughbreds, and stock horses (SH). METHODS: Ninety-six healthy horses were grouped by breed (Warmbloods, Thoroughbreds, and SH). Samples were collected through venipuncture for complete blood count analysis. One-way ANOVA with Tukey's tests or Kruskal-Wallis with Dunn's post hoc tests were used to compare hematologic variables among groups. RESULTS: Warmbloods had a significantly lower total white blood cell (WBC) count (6.08 ± 1.11 × 109/L) and lymphocyte count (1.76 ± 0.41 × 109/L) than Thoroughbreds (7.28 ± 1.45; 2.28 ± 5.16 × 109/L, respectively; P < .001) and SH (7.21 ± 1.18 × 109/L, P < .01; 2.10 ± 5.17 × 109/L; P < .05). Warmbloods had a significantly lower red blood cell count (7.7 ± 0.8 × 1012/L) and higher mean corpuscular volume (MCV, 49.4 ± 2.2 fL) than Thoroughbreds (8.42 ± 1.2 × 1012/L, P < .01; 47.3 ± 3.0 fL). Warmbloods had lower MCVs than SH (49.4 ± 2.2 vs 51.2 ± 2.6 fL). The mean cell hemoglobin concentration (MCHC) was higher in Warmbloods (35.0, 33.8-36.2 g/dL) and Thoroughbreds (34.9, 33.4-35.7 g/dL) than in SH breeds (34.0, 33.4-35.4 g/dL; P < .001, both). Total protein concentrations were significantly lower in Thoroughbreds (67, 59-80 g/L) compared with SH (71, 64-83 g/dL) (P < .05). CONCLUSIONS: Warmbloods had decreased WBC and lymphocyte counts compared with Thoroughbreds and SH, and Thoroughbreds had increased red blood cell counts. Thoroughbreds had lower total protein concentrations than SH. Clinicians should consider breed differences when interpreting hematologic values.

Changes in liver and kidney function, red blood cell count and hemoglobin levels 1 day after ultrasound-guided percutaneous microwave ablation for uterine fibroids.

OBJECTIVE: To investigate the changes in liver and kidney function, red blood cell (RBC) count and hemoglobin (HGB) levels in patients undergoing ultrasound-guided percutaneous microwave ablation (UPMWA) for uterine fibroids on postoperative day 1. METHODS: The changes in liver and kidney function, RBC count and HGB levels in 181 patients who underwent selective UPMWA in the Second Affiliated Hospital of Shantou University Medical College, China, between August 2017 and January 2023 were retrospectively analyzed. RESULTS: All patients underwent UPMWA for uterine fibroids; 179 patients had multiple uterine fibroids and 2 patients had single uterine fibroids. The maximum fibroid diameter ranged from 18 to 140 mm, with an average of 68.3 mm. Ultrasound imaging was used to confirm that the blood flow signal within the mass had disappeared in all patients, indicating that the ablation was effective. Within 24 h, compared with before UPMWA, levels of total bilirubin, direct bilirubin, indirect bilirubin and aspartate aminotransferase had significantly increased (p < 0.01), whereas levels of total protein, albumin, globulin, alanine aminotransferase, creatinine and urea had significantly decreased (p < 0.01). Acute kidney injury (AKI) occurred in 1 of the 181 patients. The RBC count and HGB levels decreased significantly after UPMWA (p < 0.01). CONCLUSION: Ultrasound-guided percutaneous microwave ablation for uterine fibroids can impose a higher detoxification load on the liver and cause thermal damage to and the destruction of RBCs within local circulation, potentially leading to AKI. Protein levels significantly decreased after UPMWA. Therefore, perioperative organ function protection measures and treatment should be actively integrated into clinical practice to improve prognosis and enhance recovery.

The protective effects of BMSA1 and BMSA5-1-1 proteins against Babesia microti infection.

The intracellular parasite Babesia microti is among the most significant species causing human babesiosis and is an emerging threat to human health worldwide. Unravelling the pathogenic molecular mechanisms of babesiosis is crucial in developing new diagnostic and preventive methods. This study assessed how priming with B. microti surface antigen 1 (BHSA 1) and seroreactive antigen 5-1-1 (BHSA 5-1-1) mediate protection against B. microti infection. The results showed that 500 µg/ml rBMSA1 and rBMSA5-1-1 partially inhibited the invasion of B. microti in vitro by 42.0 ± 3.0%, and 48.0 ± 2.1%, respectively. Blood smears revealed that peak infection at 7 days post-infection (dpi) was 19.6%, 24.7%, and 46.7% in the rBMSA1, rBmSA5-1-1, compared to the control groups (healthy mice infected with B. microti only), respectively. Routine blood tests showed higher white blood cell, red blood cell counts, and haemoglobin levels in the 2 groups (BMSA1 and BMSA5 5-1-1) than in the infection control group at 0-28 dpi. Moreover, the 2 groups had higher serum interferon-γ, tumor necrosis factor-α and Interleukin-17A levels, and lower IL-10 levels than the infection control group throughout the study. These 2 potential vaccine candidate proteins partially inhibit in vitro and in vivo B. microti infection and enhance host immunological response against B. microti infection.

Comparison of atlantoaxial and lumbosacral cerebrospinal fluid centesis techniques in South American camelids.

BACKGROUND: Iatrogenic blood contamination during cerebrospinal fluid (CSF) centesis is common, which can limit the diagnostic usefulness of the sample. A novel ultrasound-guided CSF collection technique is described in horses, by which CSF is obtained from the atlantoaxial (AA) space. HYPOTHESIS/OBJECTIVES: To compare ultrasound-guided AA centesis with lumbosacral (LS) centesis in South American camelids (SAC). The hypotheses were that AA centesis would yield samples with less blood contamination although being technically more challenging than LS centesis. ANIMALS: Eight clinically healthy adult SAC from a university-owned teaching herd. METHODS: Single-blinded, randomized, 4-way, 4-period crossover study in which 2 veterinarians each performed both centesis techniques on each animal once. Cytological sample analysis was performed, and the technical difficulty of sample acquisition was assessed. RESULTS: The CSF was collected successfully and without complications by either technique during all collection attempts. Aspects of technical difficulty and concentrations of CSF analytes did not vary significantly between techniques. Median total nucleated cell and red blood cell counts were 1/µL and 0.5/µL and 167.5/µL and 155/µL for AA and LS techniques, respectively. The median total protein concentration was 32.9 mg/dL and 38 mg/dL for AA and LS centeses. A median of 1 attempt was necessary for both centesis techniques and the median number of needle repositioning events was 1 for AA and 0 for LS. CONCLUSION AND CLINICAL IMPORTANCE: Depending on clinical circumstances, ultrasound-guided AA centesis appears to be an acceptable alternative to other techniques for collection of CSF from SAC.

Nucleated Red Blood Cell Counts Differentiate Cardiac from Respiratory Causes of Cyanosis at Birth.

Tissue hypoxia increases erythropoietin production and release of immature erythrocytes that can be measured using nucleated red blood cell counts (nRBC). We hypothesized that hypoxia due to congenital heart disease (CHD) is chronic and is better tolerated than hypoxia due to respiratory disease (RD), which is an acute stress in newborns leading to higher nRBC. This study assesses the utility of nRBC as a marker to differentiate hypoxia due to CHD vs RD in term neonates. This was a single-center, retrospective study of term neonates with cyanosis from 2015 to 2022. Neonates < 37 weeks of gestation, with hypoxic-ischemic encephalopathy, and those with other causes of cyanosis were excluded. The patients were divided into 2 groups: cyanotic CHD and cyanotic RD. Clinical and laboratory data done within 12 h and 24-36 h after birth were collected. Data are represented as median and Interquartile range. Of 189 patients with cyanosis, 80 had CHD and 109 had RD. The absolute nRBC count at ≤ 12 h of age was lower in the CHD (360 cells/mm3) compared to RD group (2340 cells/mm3) despite the CHD group having significantly lower baseline saturations. A value of 1070 cells/mm3 was highly sensitive and specific for differentiating CHD from RD. The positive predictive value for this cut-off value of 1070 cells/mm3 was 0.94 and the negative predictive value was 0.89. The absolute nRBC is a simple screening test and is available worldwide. A nRBC < 1070 cells/mm3 in cyanotic newborns should hasten the search for CHD etiology with the possible need for prostaglandin therapy.