HES and EGPA: Two Sides of the Same Coin

Approach to the patient with eosinophilia in the era of tyrosine kinase inhibitors and biologicals

PURPOSE OF REVIEW

In this review, we aim to explore the optimal approach to patients presenting with eosinophilia, considering recent advances in diagnostic and therapeutic strategies. Specifically, we focus on the integration of novel therapies into clinical practice to improve patient outcomes.

RECENT FINDINGS

Advanced insights into the clinical and genetic features of eosinophilic disorders have prompted revisions in diagnostic criteria by the World Health Organization classification (WHO-HAEM5) and the International Consensus Classification (ICC). These changes reflect a growing understanding of disease pathogenesis and the development of targeted treatment options. The therapeutic landscape now encompasses a range of established and novel therapies. For reactive conditions, drugs targeting the eosinophilopoiesis, such as those aimed at interleukin-5 or its receptor, have demonstrated significant potential in decreasing blood eosinophil levels and minimizing disease flare-ups and relapse. These therapies have the potential to mitigate the side effects commonly associated with prolonged use of oral corticosteroids or immunosuppressants. Myeloid and lymphoid neoplasms with eosinophilia and tyrosine kinase (TK) gene fusions are managed by various TK inhibitors with variable efficacy. Diagnosis and treatment rely on a multidisciplinary approach. By incorporating novel treatment options into clinical practice, physicians across different disciplines involved in the management of eosinophilic disorders can offer more personalized and effective care to patients. However, challenges remain in accurately diagnosing and risk-stratifying patients, as well as in navigating the complexities of treatment selection.

Managing Patients with Hypereosinophilic Syndrome: A Statement from the Italian Society of Allergy, Asthma, and Clinical Immunology (SIAAIC)

Hypereosinophilic syndrome (HES) encompasses a heterogeneous and complex group of different subtypes within the wider group of hypereosinophilic disorders. Despite increasing research interest, several unmet needs in terms of disease identification, pathobiology, phenotyping, and personalized treatment remain to be addressed. Also, the prospective burden of non-malignant HES and, more in general, HE disorders is currently unknown. On a practical note, shortening the diagnostic delay and the time to an appropriate treatment approach probably represents the most urgent issue, even in light of the great impact of HES on the quality of life of affected patients. The present document represents the first action that the Italian Society of Allergy, Asthma, and Clinical Immunology (SIAAIC) has finalized within a wider project aiming to establish a collaborative national network on HES (InHES-Italian Network on HES) for patients and physicians. The first step of the project could not but focus on defining a common language as well as sharing with all of the medical community an update on the most recent advances in the field. In fact, the existing literature has been carefully reviewed in order to critically integrate the different views on the topic and derive practical recommendations on disease identification and treatment approaches.

Red flags for clinical suspicion of eosinophilic granulomatosis with polyangiitis (EGPA)

BACKGROUND

Eosinophilic granulomatosis with polyangiitis (EGPA), is a rare ANCA-associated systemic vasculitis. Its overlapping features with other vasculitic or eosinophilic diseases, and the wide and heterogeneous range of clinical manifestations, often result in a delay to diagnosis.

OBJECTIVE

To identify red flags that raise a suspicion of EGPA to prompt diagnostic testing and to present an evidence-based clinical checklist tool for use in routine clinical practice.

METHODS

Systematic literature review and expert consensus to identify a list of red flags based on clinical judgement. GRADE applied to generate a strength of recommendation for each red flag and to develop a checklist tool.

RESULTS

86 studies were included. 40 red flags were identified as relevant to raise a suspicion of EGPA and assessed by the experts as being clinically significant. Experts agreed that a diagnosis of EGPA should be considered in a patient aged ≥6 years with a blood eosinophil level >1000 cells/µL if untreated and >500 cells/µL if previously treated with any medication likely to have altered the blood eosinophil count. The presence of asthma and/or nasal polyposis should reinforce a suspicion of EGPA. Red flags of asthma, lung infiltrates, pericarditis, cardiomyopathy, polyneuropathy, biopsy with inflammatory eosinophilic infiltrates, palpable purpura, digital ischaemia and ANCA positivity, usually anti-myeloperoxidase, among others, were identified.

CONCLUSION

The identification of a comprehensive set of red flags could be used to raise a suspicion of EGPA in patients with eosinophilia, providing clinicians with an evidence-based checklist tool that can be integrated into their practice.

A case report of refractory multivessel coronary spasm associated with hypereosinophilic syndrome: one cell, one disease?

Background

Hypereosinophilic syndrome (HES) is characterized by moderate to severe eosinophilia, exclusion of neoplastic or secondary origins of eosinophilia, and systemic involvement with end-organ damage. Coronary arteries can be affected to cause vasospastic angina (VSA); however, the association of the two diseases is not well recognized.

Case summary

A 55-year-old woman who had a history of multiple allergic disease such as bronchial asthma and chronic sinusitis with nasal polyps was hospitalized due to attacks of chest pain at rest. During a spontaneous attack of chest pain, ECG revealed ST-segment elevation in the inferior leads and emergency coronary angiography showed focal spasms of the right and left anterior descending coronary arteries, both of which were relieved after intracoronary administration of nitroglycerine. She was diagnosed with VSA according to the Japanese Circulation Society guidelines. Despite conventional vasodilator therapies, her resting angina remained refractory. Laboratory findings were notable for moderate eosinophilia. A comprehensive evaluation to uncover the underlying cause of refractory VSA led to the diagnosis of HES, concomitant with eosinophilic pneumonia and eosinophilic chronic rhinosinusitis. Pericoronary inflammation by fat attenuation index (FAI) was increased in the proximal segment of the right coronary artery. Treatment was initiated with oral prednisolone at a starting dose of 30 mg/day. The response to treatment was rapid, with her symptoms disappearing and a regression of eosinophilia observed the following day.

Discussion

Hypereosinophilic syndrome manifests with refractory VSA, and eosinophil-suppressing corticosteroid therapy proves effective in improving both conditions along with reduction of the pericoronary inflammation by FAI.

Multidisciplinary Decision-Making-ITAlian Consensus After Two Years of Real Practice on the Management of Severe Uncontrolled CRSwNP by Biologics (ITACA Study)

PURPOSE OF REVIEW

We aimed to reach an Italian multidisciplinary consensus on some crucial aspects of treatment decision making in CRSwNP, following 2 years of clinical experience in order to support specialists in the management of CRSwNP in clinical practice. We addressed issues relating to therapeutic decision-making and shared criteria for the treatment choice, as well as appropriate timing and criteria for evaluating treatment response, and highlighted the need for repeated multidisciplinary assessments.

RECENT FINDINGS

A national survey has been conducted recently to understand how rhinology practice has changed in Italy with the advent of biologics and how this affects patients with uncontrolled, severe CRSwNP. Despite the many published consensus documents, practical recommendations, and protocols on the use of biologics in CRSwNP, heterogenous behaviors in practice are still observed mainly conditioned by the novelty of the topic. The consensus procedure followed a modified Delphi approach. The scientific board included 18 otorhinolaryngologists and 8 allergists, who selected the 4 main topics to be addressed and developed overall 20 statements. Consensus on these statements was sought by a larger group of 48 additional experts, through two rounds of voting, the first web-based, the second in presence with discussion and possible refinement of the statements. The statements reaching an average score ≥ 7 at the second voting round were approved. Five statements were proposed for each of the following topics: baseline evaluation of patients eligible for biologic therapy; choice between different therapeutic options; assessment of the response to biologic treatment; multidisciplinary management. At the first voting round, 19 out of the 20 statements reached a mean score ≥ 7. Following the discussion and a few consequent amendments, at the second round of voting all the 20 statements were approved.

Hematological Neoplasms with Eosinophilia

Eosinophils in peripheral blood account for 0.3-5% of leukocytes, which is equivalent to 0.05-0.5 × 109/L. A count above 0.5 × 109/L is considered to indicate eosinophilia, while a count equal to or above 1.5 × 109/L is defined as hypereosinophilia. In bone marrow aspirate, eosinophilia is considered when eosinophils make up more than 6% of the total nuclear cells. In daily clinical practice, the most common causes of reactive eosinophilia are non-hematologic, whether they are non-neoplastic (allergic diseases, drugs, infections, or immunological diseases) or neoplastic (solid tumors). Eosinophilia that is associated with a hematological malignancy may be reactive or secondary to the production of eosinophilopoietic cytokines, and this is mainly seen in lymphoid neoplasms (Hodgkin lymphoma, mature T-cell neoplasms, lymphocytic variant of hypereosinophilic syndrome, and B-acute lymphoblastic leukemia/lymphoma). Eosinophilia that is associated with a hematological malignancy may also be neoplastic or primary, derived from the malignant clone, usually in myeloid neoplasms or with its origin in stem cells (myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase gene fusions, acute myeloid leukemia with core binding factor translocations, mastocytosis, myeloproliferative neoplasms, myelodysplastic/myeloproliferative neoplasms, and myelodysplastic neoplasms). There are no concrete data in standardized cytological and cytometric procedures that could predict whether eosinophilia is reactive or clonal. The verification is usually indirect, based on the categorization of the accompanying hematologic malignancy. This review focuses on the broad differential diagnosis of hematological malignancies with eosinophilia.

An 85-Year-Old Man with Fever, Dyspnea, and Dry Cough Diagnosed with Idiopathic Hypereosinophilic Syndrome, Successfully Treated with High-Dose Corticosteroids

BACKGROUND Idiopathic hypereosinophilic syndrome (I-HES) is a rare disease diagnosed as absolute eosinophil count >1500 cells/µl and end-organ involvement attributable to tissue eosinophilia with no secondary cause of underlying eosinophilia. The mean age of presentation for I-HES is 44 years. The skin, lungs, and gastrointestinal (GI) system are most common sites of presenting manifestations, including fatigue, cough, dyspnea, myalgias, angioedema, rash, fever, nausea, and diarrhea. Although cardiac and neurologic symptoms are less common at presentation, they can be life-threatening. CASE REPORT We report the case of an 85-year-old man who presented with fever, malaise, and loss of appetite for 3 weeks, followed by dyspnea and dry cough for 2 weeks. His absolute eosinophil count was 9000 cells/µl, which was not responding to empirical antibiotic therapy, with worsening of symptoms, suggesting a non-infective origin. He was then extensively evaluated to establish underlying an etiology for specific treatment, which was negative for common causes like atypical infections, malignancy, and autoimmune disorders. He was then started on corticosteroid therapy to overcome an exaggerated immune response and reduce inflammation-related injury, to which he responded well. On follow-up, hypereosinophilia was fully cured, with reversal of end-organ involvement including myocarditis and pneumonitis. CONCLUSIONS This report shows that idiopathic HES can present with various clinical features and that accurate diagnosis, excluding known causes of eosinophilia, and early management are essential to prevent long-term organ damage. Our patient responded to prompt treatment with high-dose corticosteroids.