Hypereosinophilic syndromes

When Blood Cell Counts Matter: Hypereosinophilic Syndrome as a Rare Cause of Ischemic Strokes

Hypereosinophilic syndrome (HES) is a rare condition characterized by elevated eosinophil counts (>1.5 x 109 on two consecutive measurements), which are of myeloid clonal in origin or are driven by excess cytokines. One subtype of HES exhibits the Fip1-like 1-platelet-derived growth factor receptor alpha (FIP1L1-PDGFRA) fusion gene, a gain-of-function mutation resulting in a hyperactive tyrosine kinase. HES, especially the FIP1L1-PDGFRA variant, exhibits an excellent response to chemotherapy with imatinib. In this report, we present a 38-year-old patient with no contributory past medical history who experienced sudden-onset fatigue, ataxia, visual changes, and headaches. He was found to have multiple small acute infarcts in his cerebrum and cerebellum. A stroke work-up, including transthoracic echocardiogram (TTE), transesophageal echocardiogram (TEE), and computed tomography angiography (CTA), did not yield insight into the origin of his infarcts. On CBC, he was consistently hypereosinophilic, and a bone marrow biopsy revealed hypercellularity and the FIP1L1-PDGFRA fusion gene, confirming the diagnosis of HES. The patient was treated first with methylprednisolone and then imatinib with excellent response. It appears that, in our patient, strokes were not of a thromboembolic nature but rather due to hypercoagulability. In this report, we advocate for considering HES and emphasize the importance of revisiting basic laboratory studies such as a CBC if the standard stroke workup fails to elucidate the mechanism behind ischemic strokes with an embolic pattern.

Central Nervous System and Cardiac Involvement in the Hypereosinophilic Syndrome: A Case Report

Hypereosinophilic syndrome is a rare entity and heterogeneous group of disorders characterized by hypereosinophilia and organ involvement. In this study, we presented a 49-year-old woman with cardiac tamponade in the context of Hypereosinophilic syndrome. Identifying hypereosinophilia as the underlying cause can have tremendous clinical implications for rapid initiation of appropriate treatment to minimize further end organ damage.

Differential clinicopathologic features of EGPA-associated neuropathy with and without ANCA

OBJECTIVE

To investigate the clinicopathologic features of eosinophilic granulomatosis with polyangiitis (EGPA)-associated neuropathy with a focus on the presence or absence of anti-neutrophil cytoplasmic antibodies (ANCAs).

METHODS

We examined the clinical features and pathologic findings of sural nerve biopsy specimens from 82 patients with EGPA-associated neuropathy. Of these patients, 32.9% were myeloperoxidase (MPO)-ANCA positive, and 67.1% were MPO-ANCA negative. PR3-ANCA was negative in all of 78 examined patients.

RESULTS

Upper limb symptoms were more frequently reported as initial neuropathic manifestations in the MPO-ANCA-positive group than in the MPO-ANCA-negative group (44.4% vs 14.6%, p < 0.01). The serum levels of C-reactive protein were significantly higher in the MPO-ANCA-positive group than in the MPO-ANCA-negative group (p < 0.05). Sural nerve biopsy specimens showed findings suggestive of vasculitis (i.e., destruction of vascular structures) in epineurial vessels; these results were seen more frequently in the MPO-ANCA-positive group than in the MPO-ANCA-negative group (p < 0.0001). Conversely, the numbers of eosinophils in the lumen of the epineurial vessels (p < 0.01) and epineurial vessels occluded by intraluminal eosinophils (p < 0.05) were higher in the MPO-ANCA-negative group than in the MPO-ANCA-positive group. Furthermore, the incidence of eosinophil infiltration in the endoneurium was higher in the MPO-ANCA-negative group than in the MPO-ANCA-positive group (p < 0.01).

CONCLUSIONS

This study suggests that the pathogenesis of EGPA comprises at least 2 distinct mechanisms: ANCA-associated vasculitis resulting in ischemic effects and inflammation, which is prominent in MPO-ANCA-positive patients, and eosinophil-associated vascular occlusion leading to ischemia and eosinophil-associated tissue damage, which is conspicuous in MPO-ANCA-negative patients.

Paraneoplastic hypereosinophilia in a patient with peripheral T cell lymphoma, not otherwise specified

Under normal physiological conditions, the bone marrow (BM) will have between 1% and 6% eosinophils, translating into a peripheral count of 0.05 – 0.5 ×10⁹/L eosinophils in the blood smear. This process is coordinated by transcription factors with specific roles in differentiation and activation. Secondary eosinophilia may be a paraneoplastic syndrome, related to the presence of a subsequent malignancy, as presented in this case report. Such paraneoplastic manifestations should be addressed properly in order for the patient to receive the best treatment of choice. Even if eosinophilia was associated with B-cell malignancies before, this is a report associating this symptom to a peripheral T-cell lymphoma, not other specified, thus emphasizing the importance of a complex approach for the management of the oncological patient.

P-ANCA negative eosinophilic granulomatosis with polyangiitis

Vasculitis refers to inflammation of the systemic vessels. Eosinophilic granulomatosis with polyangiitis (EGPA) is a medium and small vessel vasculitis characterized by hypereosinophilia, pulmonary infiltrates, difficult to treat asthma and polyneuropathies. Diagnosis can often be challenging. In this article, we present a case of a young lady who was diagnosed ANCA negative EGPA.

Idiopathic hypereosinophilic syndrome with pulmonary hypertension

Hypereosinophilic syndrome is a myeloproliferative disorder characterized by persistent eosinophilia with involvement of multiple organs. The occurrence of severe pulmonary hypertension (PH) in the setting of hypereosinophilic syndrome is very uncommon. A 43-year-old man with documented idiopathic hypereosinophlic syndrome presented to the hospital with symptoms of paroxysmal chest discomfort and progressive exertional dyspnea. Physical examination showed distended jugular veins, cyanosed lips, increased P2 sound, and moderate pitting edema of the lower extremities. Echocardiography revealed enlarged right atrium, enlarged right ventricle, increased pulmonary artery systolic pressure, and decreased right ventricular systolic function. Venous ultrasound of the lower extremities, computed tomography pulmonary angiography, and right heart catheterization (RHC) were negative for thrombus. The pulmonary artery systolic pressure was found severely increased during the RHC. Treatment included prednisolone, ambrisentan, diuretics, and digoxin. The involvement of the pulmonary artery in patients with idiopathic hypereosinophilic syndrome is an uncommon finding. The patient presents with clinical manifestations of right ventricular systolic dysfunction resulted from severely increased PH.

A Clinicopathologic Study of Small Intestinal Perforations in Patients With Eosinophilic Granulomatosis With Polyangiitis: A Series of 3 Patients

Eosinophilic granulomatosis with polyangiitis (EGPA) is a vascular disorder of unknown etiology characterized by severe asthma, eosinophilia, and granulomatous vasculitis. It is sometimes associated with gastrointestinal lesions, although perforations are uncommon. Corticosteroids are commonly used in the treatment of patients with EGPA; however, they may impair tissue repair and induce fibrotic changes in the vascular intima, which can lead to vascular occlusion, ischemia, and perforation. The anti-inflammatory properties of corticosteroids may mask symptoms of gastroduodenal ulcers or other intra-abdominal conditions, which can lead to a delay in diagnosis. From January 1, 2001 to December 31, 2014, 71 patients underwent surgery for small intestinal perforations. Of these, 4 operations were performed on 3 patients with EGPA who were receiving corticosteroids. We retrospectively reviewed the clinical and pathologic features of these patients. All 3 patients with EGPA were men, with a mean age of 56 years. The length of resected intestine ranged from 10 to 60 cm. Histopathologic examination revealed ulcers and perforations of the small intestine associated with vasculitis, compatible with EGPA. All patients had an uneventful postoperative course. Patients with EGPA presenting with abdominal pain must be carefully evaluated for possible intestinal perforation, especially those receiving corticosteroid therapy.

The Eosinophil in Health and Disease: from Bench to Bedside and Back

Historically, eosinophils have been considered as end-stage cells involved in host protection against parasitic infection and in the mechanisms of hypersensitivity. However, later studies have shown that this multifunctional cell is also capable of producing immunoregulatory cytokines and soluble mediators and is involved in tissue homeostasis and modulation of innate and adaptive immune responses. In this review, we summarize the biology of eosinophils, including the function and molecular mechanisms of their granule proteins, cell surface markers, mediators, and pathways, and present comprehensive reviews of research updates on the genetics and epigenetics of eosinophils. We describe recent advances in the development of epigenetics of eosinophil-related diseases, especially in asthma. Likewise, recent studies have provided us with a more complete appreciation of how eosinophils contribute to the pathogenesis of various diseases, including hypereosinophilic syndrome (HES). Over the past decades, the definition and criteria of HES have been evolving with the progress of our understanding of the disease and some aspects of this disease still remain controversial. We also review recent updates on the genetic and molecular mechanisms of HES, which have spurred dramatic developments in the clinical strategies of diagnosis and treatment for this heterogeneous group of diseases. The conclusion from this review is that the biology of eosinophils provides significant insights as to their roles in health and disease and, furthermore, demonstrates that a better understanding of eosinophil will accelerate the development of new therapeutic strategies for patients.

Platelet-derived growth factor receptors (PDGFRs) fusion genes involvement in hematological malignancies

PURPOSE

To investigate oncogenic platelet-derived growth factor receptor(PDGFR) fusion genes involvement in hematological malignancies, the advances in the PDGFR fusion genes diagnosis and development of PDGFR fusions inhibitors.

METHODS

Literature search was done using terms "PDGFR and Fusion" or "PDGFR and Myeloid neoplasm" or 'PDGFR and Lymphoid neoplasm' or "PDGFR Fusion Diagnosis" or "PDGFR Fusion Targets" in databases including PubMed, ASCO.org, and Medscape.

RESULTS

Out of the 36 fusions detected, ETV6(TEL)-PDGFRB and FIP1L1-PDGFRA fusions were frequently detected, 33 are as a result of chromosomal translocation, FIP1L1-PDGFRA and EBF1-PDGFRB are the result of chromosomal deletion and CDK5RAP2- PDGFRΑ is the result of chromosomal insertion. Seven of the 34 rare fusions have detectable reciprocals.

CONCLUSION

RNA aptamers are promising therapeutic target of PDGFRs and diagnostic tools of PDGFRs fusion genes. Also, PDGFRs have variable prospective therapeutic strategies including small molecules, RNA aptamers, and interference therapeutics as well as development of adaptor protein Lnk mimetic drugs.

Hypereosinophilic syndrome presenting with multiple organ infiltration and deep venous thrombosis: A case report and literature review

BACKGROUND

Hypereosinophilic syndrome (HES) can be fatal, particularly when eosinophils infiltrate vital organs and/or if extensive thrombosis develops. However there are no standard recommendations for the use of anticoagulant therapy of HES in the setting of thrombosis.

METHODS

We herein present a case of a 46-year-old female who presented with marked peripheral eosinophilia with symptoms of multi-organ infiltration and extensive deep venous thrombosis (DVT). In this case, evaluation was carried out before the diagnosis was established, and timely standard-dose corticosteroids combined with a new oral anticoagulant (NOAC) therapy were carried out.

RESULTS

These measures resulted in a rapid response and long-term disease control.

CONCLUSION

Although there are no data to support which anticoagulant is preferred in this setting, this case indicates that the new oral anticoagulants may play an important role in the treatment of thrombosis in HES.

Response of Complex Undefined Hypereosinophilic Syndrome to Treatment with Imatinib

Hypereosinophilic syndomes (HESs) include potentially lethal multisystem disorders characterized by eosinophilic infiltration of a variable spectrum of target organs, predominantly the skin, heart, lungs, gastrointestinal tract, and nervous system. Based on recent advances in molecular and genetic diagnostic techniques and increasing experience with differences in clinical features and prognosis, subtypes have been defined, including "myeloproliferative-HES ", "lymphocytic-HES", "familial eosinophilia", "overlap HES", "undefined HES" ("complex undefined HES", "simple undefined HES", "episodic undefined HES") and "eosinophil associated diseases" (such as Churg-Strauss syndrome). HES should be kept in mind in the differential diagnosis of eosinophilic lung diseases especially in patients with peripheral eosinophilia and pulmonary infiltrates. Corticosteroids represent an effective firstline approach to decreasing eosinophil counts in the majority of cases. Imatinib might be used for corticosteroid nonresponders. We herein report a patient with "complex undefined HES" who had disease resistant to corticosteroids, but who had a significant response after treatment with imatinib.

Atypical Presentation of Intracardiac Floating Thrombi in Hypereosinophilic Syndrome Complicated With Stroke and Systemic Embolization: A Case Report

Hypereosinophilic syndrome (HES) describes a disorder characterized by persistent peripheral blood eosinophilia with evidence of multiple target organs damage caused by eosinophilia. HES most commonly involves the heart, and cardiac involvement typically presents in the form of endomyocarditis or myocarditis with apical mural thrombus formation.We present a case with atypical cardiac presentation with massive intracardiac fragile thrombi, causing peripheral emboli and strokes.HES can present as floating thrombi with thin attachment to the left ventricle, and clinicians should also be vigilant of thromboembolic complications and initiate early therapy to prevent or reduce the potential complications of HES.

Churg-Strauss syndrome

Churg-Strauss syndrome (CSS), alternatively known as eosinophilic granulomatosis with polyangiitis (EGPA), was first described in 1951 by Churg and Strauss as a rare disease characterized by disseminated necrotizing vasculitis with extravascular granulomas occurring exclusively among patients with asthma and tissue eosinophilia. EGPA is classified as a small-vessel vasculitis associated with antineutrophil cytoplasmic antibodies (ANCAs) and the hypereosinophilic syndromes (HESs) in which vessel inflammation and eosinophilic proliferation are thought to contribute to organ damage. Although still considered an idiopathic condition, EGPA is classically considered a Th2-mediated disease. Emerging clinical observations provide compelling evidence that ANCAs are primarily and directly involved in the pathogenesis of AASVs, although recent evidence implicates B cells and the humoral response as further contributors to EGPA pathogenesis. EGPA has traditionally been described as evolving through a prodromic phase characterized by asthma and rhino-sinusitis, an eosinophilic phase marked by peripheral eosinophilia and organ involvement, and a vasculitic phase with clinical manifestations due to small-vessel vasculitis. The American College of Rheumatology defined the classification criteria to distinguish the different types of vasculitides and identified six criteria for EGPA. When four or more of these criteria are met, vasculitis can be classified as EGPA. The French Vasculitis Study Group has identified five prognostic factors that make up the so-called five-factor score (FFS). Patients without poor prognosis factors (FFS=0) have better survival rates than patients with poor prognosis factors (FFS≥1). The treatment of patients with CSS must be tailored to individual patients according to the presence of poor prognostic factors. A combination of high-dose corticosteroids and cyclophosphamide is still the gold standard for the treatment of severe cases, but the use of biological agents such as rituximab or mepolizumab seems to be a promising therapeutic alternative.

Eosinophils regulate peripheral B cell numbers in both mice and humans

The view of eosinophils (Eos) as solely effector cells involved in host parasite defense and in the pathophysiology of allergic diseases has been challenged in recent years. In fact, there is a growing realization that these cells interact with other components of innate and adaptive immunity. For example, mouse Eos were recently demonstrated to promote plasma cell retention in the bone marrow. However, it remains unknown whether Eos influence the biology of normal B lymphocytes. In this study, we specifically assessed the effect of Eos on B cell survival, proliferation, and Ig secretion. Our data first revealed that the genetic deletion of Eos from NJ1638 IL-5 transgenic hypereosinophilic mice (previously shown to display profound B cell expansion) resulted in the near abolishment of the B cell lymphocytosis. In vitro studies using human tissues demonstrated Eos' proximity to B cell follicles and their ability to promote B cell survival, proliferation, and Ig secretion via a contact-independent mechanism. Additionally, this ability of Eos to enhance B cell responsiveness was observed in both T-independent and T-dependent B cell activation and appears to be independent of the activation state of Eos. Finally, a retrospective clinical study of hypereosinophilic patients revealed a direct correlation between peripheral blood eosinophil levels and B cell numbers. Taken together, our study identifies a novel role for Eos in the regulation of humoral immunity via their impact on B cell homeostasis and proliferation upon activation.

FIP1L1-PDGFRα-positive hypereosinophilic syndrome in childhood: a case report and review of literature

Hypereosinophilic syndromes in children are rare disorders traditionally characterized by an eosinophil count exceeding 1,500/mm³ on at least 2 occasions or evidence of tissue eosinophilia associated with symptoms and marked blood eosinophilia, lacking any secondary cause (such as infections, allergic disease, chemical-induced eosinophilia, hypoadrenalism, cancer). Until now there have only been 3 reported cases of pediatric FIP1L1-PDGFRα-positive hypereosinophilic syndromes. We describe a fourth patient, a white 14-year-old boy, the third treated with imatinib.

A novel subtype of myeloproliferative disorder? JAK2V617F-associated hypereosinophilia with hepatic venous thrombosis

We report the case of a 27-year-old man, presenting with one episode of massive haematemesis and a history of persistent eosinophilia for the past 8 months. An evaluation revealed hepatic cirrhosis with portal hypertension, secondary to chronic Budd-Chiari syndrome. Further investigations confirmed a diagnosis of hypereosinophilic syndrome. Molecular genetic analysis was negative for FIP1L1-PDGFRA gene rearrangement, but positive for JAK2V617F mutation.

Löffler endocarditis: a rare cause of acute cardiac failure

We describe a patient with acute cardiogenic shock due to cardiac involvement in idiopathic hypereosinophilic syndrome (Löffler endocarditis). At the echocardiography, there was a huge mass in the left ventricular cavity, resulting in inflow- and outflow tract obstruction. The posterior leaflet of the mitral valve apparatus was completely embedded in a big (organized) thrombus mass. The patient was treated with high dose corticosteroids, however without effect. Partial remission was achieved after treatment with hydroxycarbamide. He was also treated with anticoagulants and high dose beta-blockers. The patient’s condition improved remarkably after correction of the mitral valve insufficiency by a mitral valve bioprosthesis.

Churg-strauss syndrome: an update

Churg-Strauss syndrome is an uncommon disease of unknown cause described initially by Churg and Strauss in 1951. Even though it was initially thought to be a variant of polyarteritis nodosa, its pathological, clinical, and laboratory features show that it is related to the small vessel vasculitides, and it is now classified as an antineutrophil cytoplasmic antibody-associated vasculitis. The presence of asthma, usually of adult onset, along with other allergic symptoms, peripheral and tissue eosinophilia, is specific to this disease. These features usually help clinicians distinguish it from other types of small vessel vasculitis and should alert clinicians about its presence. Two different clinical subtypes defined by the presence of antineutrophil cytoplasmic antibodies recently have been recognized. Recent advances in the treatment and pathophysiology of Churg-Strauss syndrome are reviewed in this article.

Ulnar mononeuropathy associated with eosinophilia

A boy aged 4.5 years presented with isolated left ulnar nerve motor neuropathy and moderate eosinophilia. There was no evidence of parasitic infection. He was commenced on empirical diethylcarbamazine citrate and albendazole. Improvement occurred 6 days later with complete recovery by 2 weeks. It is presumed that he had a parasitic infection.

Inhibition of NF-κB signaling retards eosinophilic dermatitis in SHARPIN-deficient mice

The NF-κB pathway performs pivotal roles in diverse physiological processes such as immunity, inflammation, proliferation, and apoptosis. NF-κB is kept inactive in the cytoplasm through association with inhibitors (IκB), and translocates to the nucleus to activate its target genes after the IκBs are phosphorylated and degraded. Here, we demonstrate that loss of function of SHANK-associated RH domain interacting protein (SHARPIN) leads to activation of NF-κB signaling in skin, resulting in the development of an idiopathic hypereosinophilic syndrome (IHES) with eosinophilic dermatitis in C57BL/KaLawRij-Sharpin(cpdm)/RijSunJ mice, and clonal expansion of B-1 B cells and CD3(+)CD4(-)CD8(-) T cells. Transcription profiling in skin revealed constitutive activation of classical NF-κB pathways, predominantly by overexpressed members of IL1 family. Compound-null mutants for both the IL1 receptor accessory protein (Il1rap(tm1Roml)) and SHARPIN (Sharpin(cpdm)) resulted in mice having decreased skin disease severity. Inhibition of IκBA degradation by the proteasome inhibitor bortezomib alleviated the dermatitis in Sharpin(cpdm) mice. These results indicate that absence of SHARPIN causes IHES with eosinophilic dermatitis by NF-κB activation, and bortezomib may be an effective treatment for skin problems of IHES.

Clinical manifestations and treatment of Churg-Strauss syndrome

Churg-Strauss syndrome (CSS) is a systemic necrotizing vasculitis affecting small to medium-sized vessels, and characterized by asthma, blood hypereosinophilia, and eosinophil-rich granulomatous inflammation of the respiratory tract. In the past few years the pathogenesis of the disease and its clinical manifestations have been clarified, fostering important advances in the treatment of CSS. Systemic corticosteroids are still considered the cornerstone of treatment. Many issues need to be addressed, such as how to maintain remission, prevent disease relapses, and treat refractory disease. This review provides a clinical overview of CSS and a summary of the current treatments and novel therapies.

Glucocorticosteroid-sensitive inflammatory eosinophilic pseudotumor of the bladder in an adolescent: a case report

Introduction

Inflammatory eosinophilic pseudotumor of the bladder is a rare inflammatory bladder disease. The etiology and pathophysiology of this condition are still unclear. Few case reports have described inflammatory eosinophilic pseudotumor of the bladder in adults or children. Although benign, this disease is occasionally clinically aggressive and locally invasive, thus open surgical removal or complete transurethral resection is recommended.

Case presentation

We present the case of a biopsy-proven inflammatory eosinophilic pseudotumor of the bladder in a previously healthy 16-year-old male adolescent with 2-month history of frequent micturition and dysuria with no significant apparent causative factors. The tumor regressed after a 6-week course of glucocorticosteroids.

Conclusion

To the best of our knowledge, our case is a rare case of inflammatory eosinophilic pseudotumor of the bladder treated with complete conservative management. Due to its glucocorticosteroid-sensitive nature, we postulate that this disease belongs to a subgroup of eosinophilic disorders.