Biomarkers predicting the controller dose of omalizumab in patients with chronic spontaneous urticaria.

BACKGROUND: Clinical trials showed the efficacy of 300 mg/4 weeks of omalizumab (OMA) during 6 months in patients with severe chronic spontaneous urticaria (CSU). Nevertheless, in real life, many patients require higher doses and/or longer treatment. This study assesses the real-life performance of OMA in severe CSU and identifies factors associated with the response. METHODS: CSU patients eligible for OMA were recruited prospectively. Clinical data and a blood test were collected before OMA initiation. Urticaria Activity Score 7 (UAS7) was calculated at baseline and every 3 months during OMA treatment. CSU control was defined as UAS7 <7 points. This work was partially sponsored by OMA manufacturer. RESULTS: Eighty-nine adults (19.1% males) with severe CSU were recruited. Median duration of CSU prior to OMA initiation was 2 years, and median severity by UAS7 at baseline was 24 points (range 10-42 points). OMA controlled 94.4% of patients, but 17.9% of responders required doses >300 mg/4 weeks. A blood basophil count >20 cells/µL (OR 13.33; 95% CI 3.32-52.63; p < .001) and the absence of hypothyroidism (OR 3.65; 95% CI 0.78-16.95; p = .099) were identified as predictive factors to achieve control with 300 mg/4 weeks. Twelve patients were able to stop OMA during the study (responders in remission, RR). RR had received OMA for a median of 29 months (12-53 months). Conversely, 32 patients had been on OMA for >29 months at the end of the study (active responders, AR). AR had received OMA for a median of 45 months (30-100 months). There were no significant differences in clinical or analytical factors between RR and AR patients. CONCLUSIONS: Low blood basophil count and the presence of hypothyroidism might serve as biomarkers for the controller dose of OMA in severe CSU patients.

Causal relationship between blood traits and severe influenza A(H1N1)pdm09 infection in East Asian: A Mendelian randomization study.

Although a range of blood traits have been reported to be associated with influenza A(H1N1)pdm09 (H1N1pdm09) disease severity, their underlying causal relationships and biological mechanisms have remained unclear. This study aimed to investigate the causal relationship between blood traits and H1N1pdm09 using a two-sample Mendelian randomization analysis. Based on the data from our in-house genome-wide association study (GWAS) on H1N1pdm09 disease severity (Ncase [severe] = 70, Ncontrol [mild] = 95) and GWAS summaries of 44 blood traits from Biobank Japan (N = 12 303-143 658), we identified the potential causal effect of blood traits on severe H1N1pdm09. The inverse variance weighted method analysis revealed significant causal effects of lower aspartate aminotransferase (AST, ß = -3.212, p = 0.019), low-density-lipoprotein cholesterol (LDL-C, ß = -1.372, p = 0.045), and basophil counts (Baso, ß = -1.638, p = 0.047) on severe H1N1pdm09 disease. Additionally, polygenic risk score analysis further confirmed genetic overlap between these blood traits and severe H1N1pdm09 disease. This study provided evidence linking the lower level of AST, LDL-C, and lower count of Baso with severe H1N1pdm09 disease, potentially identifying new therapeutic targets for patients with severe influenza.

Predicting asphyxia in term fetus.

This aim of this study was to investigate maternal hematological laboratory parameters of term infants before birth diagnosed with asphyxia compared to mothers of healthy term infants and predict asphyxia by these parameters. This study was conducted on 109 and 192 mothers of the fetus with asphyxia and healthy, respectively. Laboratory parameters of complete blood count, including PDW (platelet distribution width), PCT (procalcitonin) and NLR (neutrophil/lymphocyte ratio), were recorded before birth from pregnant women. PDW and basophil counts were significantly higher in the asphyxia group than healthy group (p: .000). The cut-off level of 19.425 accurately predicted the occurrence of asphyxia (AUC = 0.724 (95% confidence interval 0.65-0.78), p = .000). Basophil count could predict asphyxia, especially the cut-off level of> 0.15(10³/µL) (AUC = 0.67) (95% confidence interval 0.60-0.74, p = .000). To predict asphyxia before labor, a cheap and routine test of PDW can be used after more research in this area.IMPACT STATEMENTWhat is already known on this subject? Asphyxia is still an unsolved problem in neonatal mortality and morbidity, and it is seen in babies of mothers who carry some risks during pregnancy (such as multiple pregnancy, baby of mother with preeclampsia, meconium aspiration, diabetes); however, it is known that it is a subject that is still not fully understood as it can also occur as a result of labor that does not have any risk factors and goes well.What do the results of this study add? In term fetuses without risk factors, it can be predicted to a certain extent whether the fetus will be diagnosed with asphyxia from the hemogram test that can work from the blood of the mother before birth.What are the implications of these findings for clinical practice and/or further research? In clinical practice, asphyxia can be estimated with a cheap and simple test, without any extra examination, by looking at the routine blood tests taken from the mother before going into labor.

Higher basophil count decreases narcolepsy risk: a Mendelian randomization study.

BACKGROUND: Blood cell properties effectively reflect immune status. Basophil and CD8+ CD27+ T cell levels are correlated with narcolepsy, but their causal association is unclear. This study aims to evaluate the causality between blood cell count and narcolepsy risk at the genetic level. METHODS: Two-sample Mendelian randomization (MR) analyses were performed on 35 published blood cell properties, using genome-wide association study (GWAS) datasets and one published GWAS dataset of narcolepsy, to explore causality between blood cell count and narcolepsy risk. Inverse variance weighted, MR-Egger, and weighted median approaches were employed for the MR analysis, odds ratio (OR) calculations, and heterogeneity tests of single nucleotide polymorphisms were conducted with the TwoSampleMR package in R. Multivariable Mendelian randomization (MVMR) was used to adjust the analysis further and eliminate the mediation effect between exposures. RESULTS: Basophil counts, total basophil neutrophil counts, total neutrophil eosinophil counts, granulocyte counts, and myeloid white cell counts showed inverse associations with narcolepsy risk based on the two-sample MR analysis. MVMR confirmed that only basophil counts were significantly associated with narcolepsy risk for the blood cell properties tested (OR = 0.23, 95% confidence interval 0.08-0.62; p = 0.004, power = 99.99%). Each standard deviation increase in basophil count (0.03 per nL), compared to the median level (0.04 per nL), decreased narcolepsy risk by 77%. CONCLUSION: Higher white blood cell counts, especially basophil counts, are protective factors for narcolepsy. Basophil counts has great potential to be used as a new biomarker to shorten diagnostic delay and to monitor the therapeutic effects of treatments for narcolepsy.

The role of laboratory hematology between technology and professionalism: the paradigm of basophil counting.

Starting from the discussion topics triggered by Hoffmann about the past and current basophil counting, a broader view of the role and future of laboratory hematology, passing through some general considerations concerning the idea of laboratory medicine in the healthcare pathway between technology and professionalism, is here provided.

Correlations between disease activity, autoimmunity and biological parameters in patients with chronic spontaneous urticaria.

Summary: Background. Biomarkers of disease activity/severity and criteria of autoimmune chronic spontaneous urticaria (CSU) are still a matter of debate. Objective. To investigate possible correlations between clinical and biological markers and their associations with: 1) disease activity, 2) resistance to H1-antihistamines, 3) autoimmunity and 4) autologous serum skin test (ASST) in patients with CSU. To also analyze biological parameter modifications in patients with CSU treated with omalizumab. Materials and methods. Disease activity, H1-antihistamines response and presence of concomitant autoimmune disease were prospectively recorded in 95 patients with CSU. For 60 of them, ASST was performed. Broad biological analysis were performed. Results. C-reactive protein (CRP) serum levels were higher in H1-antihistamines unresponders (p less-than 0.0001) and in more active diseases (p = 0.033). D-dimer plasma levels were higher in H1-antihistamines unresponders (p = 0.008) and in patients with autoimmune status (concomitant autoimmune disease and/or with autoantibodies) (p = 0.016). Total immunoglobuline E (IgE) serum level was lower in patients with positive ASST. Blood basophil counts were lower in patients with CSU and especially in H1-antihistamines unresponders (p = 0.023), in patients with more active disease (p = 0.023), with positive ASST (p = 0.001), and with autoimmune status (p = 0.057). Conversely, under omalizumab, a decrease of CRP (p = 0.0038) and D-dimer serum/plasma levels (p = 0.0002) and an increase of blood basophil counts (p = 0.0023) and total IgE serum levels (p = 0.0007) were observed. Conclusions. This study brings additional evidences of interest to investigate IgE, D-dimer serum/plasma levels and basophil blood counts in patients with CSU as they could be correlated to disease activity, response to treatment and/or autoimmunity.

Long-Term Efficacy and Clinical Remission After Benralizumab Treatment in Patients with Severe Eosinophilic Asthma: A Retrospective Study.

Background: Few studies on the long-term efficacy of benralizumab, an anti-interleukin-5 receptor α monoclonal antibody, have been conducted for patients with severe eosinophilic asthma (SEA), especially regarding the improvement of pulmonary function and clinical remission in a real-world setting. Objective: To elucidate the long-term efficacy and clinical remission rate (CRR) in patients with SEA. Methods: From July 2018 to July 2022, 23 Japanese patients with SEA received benralizumab for two years or more at Jikei University Hospital. We retrospectively evaluated the patients' characteristics, biomarkers, number of exacerbations, pulmonary function, asthma symptoms, maintenance oral corticosteroid (OCS) dose and CRR. Results: The mean observation period was 38.3 (24-49) months. Among the 23 patients, 10 patients switched from mepolizumab to benralizumab. After administration of benralizumab, the forced expiratory volume in one second (FEV1) increased and was maintained for two years in the biologic-naïve group and in the switching group (177 ± 404 and 151 ± 236 [mL], respectively, P = 0.80). In all patients, the %FEV1 improved from 76.7 ± 22.9% to 84.3 ± 18.4% (P = 0.016), and the number of annual exacerbations decreased from 2.5 ± 3.3 to 0.74 ± 1.7 (P = 0.014). Furthermore, the Asthma Control Test score significantly improved, and the reduction in OCS dose was maintained for three years. Ultimately, five patients met the clinical remission criteria and exhibited stabilization of pulmonary function, no exacerbation, no OCS use and well-controlled symptoms. The CRR was significantly higher in patients with a blood basophil count (BBC) ≥ 22 than in those with a BBC < 22 (/µL) (38.5% vs 0%, respectively, P = 0.046). Conclusion: Long-term treatment with benralizumab significantly improved pulmonary function, alleviated asthma symptoms and decreased the number of exacerbations at two years in a real-world setting. The CRR may be associated with the BBC at baseline.

The Absolute Basophil Count.

The absolute basophil count (cells/L) can be determined by manual counting of peripheral blood smears or using cell counting chambers as well as by automated hematology analyzers and fluorescence flow cytometry. Manual basophil counting of peripheral blood smears is currently regarded as the reference method, although the limitations of this method (distribution, observer, and statistical errors) are widely recognized. Automated hematology analyzers offer an advantage of larger numbers of counted cells and high throughput but are characterized by inconsistent analytical performance for basophil enumeration. Flow cytometric enumeration of circulating basophils using panels of monoclonal antibodies is being developed as novel candidate reference method for the absolute basophil count in peripheral blood. Basophil counting using fluorescence flow cytometry is characterized by high precision and statistical superiority. Emerging innovative technologies for absolute cell counts include imaging flow cytometry, mass cytometry, and on-chip blood counting, but their analytical performance for absolute basophil counts is yet to be established. Here, we describe various techniques for absolute basophil counting in peripheral blood including manual basophil counts in smears and hemocytometers and flow cytometric methodologies using double-platform, bead-based, and volumetric approaches.