Association of the blood eosinophil count with end-organ symptoms

Temporal trends of blood eosinophilia in severe uncontrolled CRSwNP treated with dupilumab: a real-life study

PURPOSE

Induced eosinophilia is commonly related to dupilumab treatment. We analysed the temporal trends of blood eosinophilia in patients with severe uncontrolled CRSwNP during the first year of treatment with dupilumab in real-life setting to evaluate its correlation with outcomes of response and adverse events (AEs).

METHODS

Seventy-four patients with severe uncontrolled CRSwNP treated with dupilumab at our institution were enrolled. At each visit, we evaluated AEC, outcomes of response to treatment and AEs.

RESULTS

A significant increase in AEC was observed since the first month with a peak at 3 months; at 12 months, the values returned comparable to those at baseline. A ≥ 50% increase of the baseline AEC with a value greater than 500 cells/mm3 was documented in 38/74 patients (Group A) regardless of the time of observation, whereas in 36/74 patients (Group B), no changes were observed. Analysing the blood eosinophilia trend over time in group A, we observed a temporary eosinophilia with early onset (within 6 months), persistent eosinophilia with early onset, and eosinophilia with late onset. No differences in terms of outcomes of response to treatment or AEs were found between Group A and Group B, or between patients who developed an AEC ≥ 1500 cells/mm3 or not.

CONCLUSION

In our series, we observed that an increase in AEC with different temporal trends may be observed in CRSwNP patients during the first year of treatment with dupilumab. In our series, eosinophilia is not correlated with a negative outcome of response to treatment or a risk of AEs.

Hypereosinophilic syndrome: a rare cause of ST-elevation myocardial infarction and thrombus formation on the aortic valve

We present a case of a man in his 30s presenting with ST-segment elevation myocardial infarction and eosinophilia. The patient underwent thrombus aspiration and initially echocardiographic evaluation was normal. The patient was discharged after 2 days, but was hospitalised again after 6 days. Echocardiographic evaluation now revealed a thrombus formation on the aortic valve. Laboratory data revealed increasing eosinophilia, and treatment with high-dosage corticosteroids and hydroxyurea was initiated as eosinophilic disease with organ manifestations could not be precluded. Eosinophils normalised and the patient was discharged again. The combination of hypereosinophilia and absence of infection, rheumatological disorders and malignancy, led to reactive or idiopathic hypereosinophilic syndrome being the most plausible diagnoses. The patient was closely monitored in the cardiology and haematology outpatient clinics. Echocardiographic evaluation, performed 6 weeks after the patient was discharged, showed significant regression in the size of the thrombus mass.

The multidisciplinary approach to eosinophilia

Eosinophilic granulocytes are normally present in low numbers in the bloodstream. Patients with an increased number of eosinophilic granulocytes in the differential count (eosinophilia) are common and can pose a clinical challenge because conditions with eosinophilia occur in all medical specialties. The diagnostic approach must be guided by a thorough medical history, supported by specific tests to guide individualized treatment. Neoplastic (primary) eosinophilia is identified by one of several unique acquired genetic causes. In contrast, reactive (secondary) eosinophilia is associated with a cytokine stimulus in a specific disease, while idiopathic eosinophilia is a diagnosis by exclusion. Rational treatment is disease-directed in secondary cases and has paved the way for targeted treatment against the driver in primary eosinophilia, whereas idiopathic cases are treated as needed by principles in eosinophilia originating from clonal drivers. The vast majority of patients are diagnosed with secondary eosinophilia and are managed by the relevant specialty-e.g., rheumatology, allergy, dermatology, gastroenterology, pulmonary medicine, hematology, or infectious disease. The overlap in symptoms and the risk of irreversible organ involvement in eosinophilia, irrespective of the cause, warrants that patients without a diagnostic clarification or who do not respond to adequate treatment should be referred to a multidisciplinary function anchored in a hematology department for evaluation. This review presents the pathophysiology, manifestations, differential diagnosis, diagnostic workup, and management of (adult) patients with eosinophilia. The purpose is to place eosinophilia in a clinical context, and therefore justify and inspire the establishment of a multidisciplinary team of experts from diagnostic and clinical specialties at the regional level to support the second opinion. The target patient population requires highly specialized laboratory analysis and therapy and occasionally has severe eosinophil-induced organ dysfunction. An added value of a centralized, clinical function is to serve as a platform for education and research to further improve the management of patients with eosinophilia. Primary and idiopathic eosinophilia are key topics in the review, which also address current research and discusses outstanding issues in the field.

Characteristics of patients with incidental eosinophilia admitted to a tertiary hospital in southern China

Background

The characteristics of patients with eosinophilia are heterogeneous and the outcomes can vary from asymptomatic to severe.

Objective

To describe the feature of patients with eosinophilia in a single center.

Design

Based on the electronic medical records from Yangjiang People's Hospital in China, the inpatients admitted between June 2018 and February 2021 with measured blood eosinophil counts were evaluated.

Methods

Eosinophilia was defined as a peripheral blood eosinophil count of ≥0.5 × 10⁹/L. Differences were compared by eosinophilia severity. The medical records of patients with moderate to severe eosinophilia were reviewed and summarized in terms of examination, diagnoses and management. And these patients were matched with patients without incidental eosinophilia by propensity score and the differences were compared.

Results

A total of 7,835 patients with eosinophilia were identified out of 131,566 total inpatients. All types of eosinophilia were most common in males (8.2%; 5,351/65,615), and in patients aged 0-6 years (11.6%; 1,760/15,204), and in the pediatric (10.8%; 1,764/16,336) department, followed by dermatology (10.6%; 123/1,162), Oncology (7.5%; 394/5,239) and Intensive care unit (ICU) (7.4%; 119/1,608). Patients with moderate to severe eosinophilia were more likely to admit to ICU (moderate: 1.3%; severe: 0.50%). In patients with moderate to severe eosinophilia, only 205/621 (33%) had eosinophilia mentioned in their records, and only 63/621 (10.1%) underwent investigations for eosinophilia. The majority of patients with moderate to severe eosinophilia (372/621, 59.9%) had an infectious disease, and little examination (7.4%; 46/621) was taken to identify the cause of eosinophilia, and only 39/621 (6.3%) of patients had a discrete cause of eosinophilia identified. Patients with moderate to severe eosinophilia (24.3%; 151/621) exhibited certain chance to have organ dysfunction.

Conclusion

Incidental eosinophilia in inpatients was frequently neglected and less investigated. Multidisciplinary consultation may improve outcomes of inpatients with moderate to severe eosinophilia.

Dupilumab-induced hypereosinophilia: review of the literature and algorithm proposal for clinical management

INTRODUCTION

Dupilumab is a human monoclonal antibody that targets both IL-4 and IL-13 signaling. It is currently indicated for the treatment of asthma, moderate-to-severe atopic dermatitis, and chronic rhinosinusitis with nasal polyps (CRSwNP). Eosinophilia has been reported as a potential adverse event in treated patients.

AREAS COVERED

A selective search on PubMed and Medline up to January 2022 was performed, by focusing on dupilumab-induced hypereosinophilia described in clinical trials, real-life studies, and case reports. The possible mechanisms underlying dupilumab-induced hypereosinophilia and the eosinophil-related morbidity have also been explored.

EXPERT OPINION

Dealing with dupilumab-induced hypereosinophilia represents a clinical challenge for clinicians managing patients on dupilumab therapy. An algorithm for the practical management of dupilumab-induced hypereosinophilia has been proposed, in order to properly investigate potential eosinophil-related morbidity and avoid unnecessary drug discontinuation.

Eosinophilic airway diseases: basic science, clinical manifestations and future challenges

Eosinophils have a broad range of functions, both homeostatic and pathological, mediated through an array of cell surface receptors and specific secretory granules that promote interactions with their microenvironment. Eosinophil development, differentiation, activation, survival and recruitment are closely regulated by a number of type 2 cytokines, including interleukin (IL)-5, the key driver of eosinophilopoiesis. Evidence shows that type 2 inflammation, driven mainly by interleukin (IL)-4, IL-5 and IL-13, plays an important role in the pathophysiology of eosinophilic airway diseases, including asthma, chronic rhinosinusitis with nasal polyps, eosinophilic granulomatosis with polyangiitis and hypereosinophilic syndrome. Several biologic therapies have been developed to suppress type 2 inflammation, namely mepolizumab, reslizumab, benralizumab, dupilumab, omalizumab and tezepelumab. While these therapies have been associated with clinical benefits in a range of eosinophilic diseases, their development has highlighted several challenges and directions for future research. These include the need for further information on disease progression and identification of treatable traits, including clinical characteristics or biomarkers that will improve the prediction of treatment response. The Nordic countries have a long tradition of collaboration using patient registries and Nordic asthma registries provide unique opportunities to address these research questions. One example of such a registry is the NORdic Dataset for aSThmA Research (NORDSTAR), a longitudinal population-based dataset containing all 3.3 million individuals with asthma from four Nordic countries (Denmark, Finland, Norway and Sweden). Large-scale, real-world registry data such as those from Nordic countries may provide important information regarding the progression of eosinophilic asthma, in addition to clinical characteristics or biomarkers that could allow targeted treatment and ensure optimal patient outcomes.

Pediatric Acute Lymphoblastic Leukemia With Hypereosinophilia and IDH2 Gene Mutation: A Case Report and Literature Review

Eosinophilia is a rare presentation of acute lymphoblastic leukemia (ALL) within the pediatric population. In this report, we present a patient with pre-B ALL and eosinophilia in the setting of an isocitrate dehydrogenase-2 gene mutation. These mutations have been described in patients with acute myeloid leukemia but in very few patients with ALL.

Obese, non-eosinophilic asthma: frequent exacerbators in a real-world setting

OBJECTIVE

In the UK, asthma deaths are at their highest level this century. Increased recognition of at-risk patients is needed. This study phenotyped frequent asthma exacerbators and used machine learning to predict frequent exacerbators.

METHODS

Patients admitted to a district general hospital with an asthma exacerbation between 1st March 2018 and 1st March 2020 were included. Patients were organized into two groups: "Infrequent Exacerbators" (1 admission in the previous 12 months) and "Frequent Exacerbators" (≥2 admissions in the previous 12 months). Patient data were retrospectively collected from hospital and primary care records. Machine learning models were used to predict frequent exacerbators.

RESULTS

200 patients admitted for asthma exacerbations were randomly selected (73% female; mean age 47.8 years). Peripheral eosinophilia was uncommon in either group (21% vs 19%). More frequent exacerbators were being treated with high-dose ICS than infrequent exacerbators (46.5% vs 23.2%; P < 0.001), and frequent exacerbators used more SABA inhalers (10.9 vs 7.40; P = 0.01) in the year preceding the current admission. BMI was raised in both groups (34.2 vs 30.9). Logistic regression was the most accurate machine learning model for predicting frequent exacerbators (AUC = 0.80).

CONCLUSIONS

Patients admitted for asthma are predominately female, obese and non-eosinophilic. Patients who require multiple admissions per year have poorer asthma control at baseline. Machine learning algorithms can predict frequent exacerbators using clinical data available in primary care. Instead of simply increasing the dose of corticosteroids, multidisciplinary management targeting Th2-low inflammation should be considered for these patients.

Time-dependent blood eosinophilia count increases the risk of kidney allograft rejection

Background

Growing evidence suggest that type 2 immune effectors play a role in solid organ transplantation. The aim of this study was to evaluate the impact of blood count eosinophils (BCEo) on immunological outcomes in kidney transplant recipients with stable graft function after 3 months post-transplant.

Method

We performed cause-specific Cox model considering BCEo, the use of calcineurin inhibitors and systemic corticoids as time-dependent explicative variables on a prospective cohort of 1013 kidney transplant patients who experienced kidney allograft rejection and/or the appearance of de novo donor specific antibodies after excluding common causes of increased BCEo..

Findings

BCEo ≥ 0.3 G/L was associated with a 3-fold increased risk of rejection independent of immunosuppressive regimen after 3 months post-transplant in patients without pre-transplant DSAs and with CNI-based immunosuppression. No association between BCEo either with donor specific antibodies or graft survival was noticed.

Interpretation

These observations in this large cohort support the hypothesis of eosinophils in allo-immunity in human and claim for further mechanistic research.

Funding

This study was supported by the French National Research Agency, The “Institut de Recherche en Santé Respiratoire des Pays de la Loire” and the University hospital of Nantes.

The role of peripheral eosinophilia in diagnosing lung disorders: experience from a single pneumonological center

Background

Eosinophilia is rare but one of the important reasons to refer patients to pneumonological centers. Determining etiology of eosinophilia has practical implications for therapeutic intervention and disease prognosis. The study aimed to determine the role of peripheral eosinophilia in the diagnosis of lung disorders.

Methods

In this retrospective study were included 46 patients diagnosed with peripheral eosinophilia with coexisting respiratory symptoms and/or radiologically detected lung lesions. All patients underwent standard diagnostic procedures, including a detailed clinical history review, physical examination, routine laboratory tests with basal cardiological examinations, and serological tests to detect parasites and allergies. Other procedures carried out depended on the symptoms of each patient. The relation between eosinophil counts in the blood and patients’ clinical manifestation was investigated to identify the degree of eosinophilia requiring immediate diagnostic procedures and treatment. Statistical analyses were performed using scientific computation libraries in the Python programming language, SciPy, v. 1.3.1. Briefly, the following tests were used: parametric Kruskal-Wallis H test, an independent t-test, ANOVA, the Shapiro- Wilk test, Fisher’s and Chi-squared tests, and the Holm-Bonferroni method.

Results

Severe eosinophilia (≥5,000 cells/μl) was associated with extrapulmonary involvement and constitutional symptoms. Skin, heart, and pleural diseases were more frequent in these patients than in patients with mild or moderate eosinophilia (p=0.010, p=0.040, and p=0.007, respectively), and only these patients showed signs of kidney disease (p=0.006). Vasculitis was significantly more frequent in the severe eosinophilia group (p=0.048) than in the other two groups. In patients with moderate eosinophilia (1,500-5,000 cells/μl), extrapulmonary symptoms were less common, although signs of cardiac involvement were confirmed in 44% of subjects. In this group, vasculitis was the most commonly observed disease (42% of cases). Mild eosinophilia (<1,500 cells/μl) was mainly associated with airway disease. In this group, vasculitis and interstitial lung diseases were identified, but most were not typically connected with eosinophilia.

Conclusions

Identification of peripheral eosinophilia may essentially determine diagnostic procedures in patients with lung disorders and may be a useful indicator of disease etiology.