Response to Imatinib Mesylate in a Patient with Idiopathic Hypereosinophilic Syndrome Associated with Cyclic Eosinophil Oscillations

"Idiopathic Eosinophilic Vasculitis": Another Side of Hypereosinophilic Syndrome? A Comprehensive Analysis of 117 Cases in Asthma-Free Patients

BACKGROUND

The absence of asthma may rule out a diagnosis of eosinophilic granulomatosis with polyangiitis in patients with hypereosinophilic syndrome (HES) and features of vasculitis.

OBJECTIVE

To describe eosinophilic vasculitis (EoV) as a possible manifestation of HES in asthma-free patients.

METHODS

We screened our hospital database and the literature for patients with HES who met the following 4 criteria: (1) histopathological or clinical features of EoV (biopsy-proven vasculitis with predominant eosinophilic infiltration of the vessel wall and/or features of vasculitis with tissue and/or blood hypereosinophilia [absolute eosinophil count >1.5 G/L]); (2) no other obvious causes of reactive eosinophilia, organ damage, and vasculitis; (3) the absence of antineutrophil cytoplasmic antibodies; and (4) the absence of current asthma.

RESULTS

Ten of our 83 (12%) asthma-free patients with HES and 107 additional cases in the literature met the criteria for EoV. After a critical analysis of the patients' clinical and laboratory characteristics and outcomes, we identified 41 cases of single-organ EoV (coronary arteritis, n = 29; temporal arteritis, n = 8; cerebral vasculitis, n = 4). Of the remaining 76 patients with EoV, the most frequent manifestations (>10%) were cutaneous vasculitis (56%), peripheral neuropathy (24%), thromboangiitis obliterans-like disease (16%), fever (13%), central nervous system involvement (13%), deep venous thrombosis (12%), and nonasthma lung manifestations (12%). Blood hypereosinophilia more than 1.5 G/L was observed in 79% of patients, and necrotizing vasculitis was observed in 44%.

CONCLUSIONS

Our results suggest that idiopathic EoV (HES-associated vasculitis) can be classified as an eosinophilic-rich, necrotizing, systemic form of vasculitis that affects vessels of various sizes in asthma-free patients.

Effectiveness of a combination of cyclosporine A, suplatast tosilate and prednisolone on periodic oscillating hypereosinophilia

We report the treatment course of a 29-year-old man who has had unique oscillating FIP1L1-PDGFRA fusion gene-negative hypereosinophilic syndrome (HES) for nearly 6 years. His periodic oscillating pattern of eosinophilia associated with angioedematous soft tissue swelling has shown two to three seasonal peaks (>15,000/μL absolute eosinophil counts [AEC]) a year. Initially, the patient, who was thought to have distinct HES not compatible with previously described cases, did not respond to treatment except for a temporary response to imatinib mesylate. For 6 years, from 2005 to 2010, he was treated with a combination of oral cyclosporine A, suplatast tosilate, and a small dose of prednisolone, which significantly reduced the peak heights of AEC as well as blunting the oscillating patterns.

Molecular Analysis of Chronic Eosinophilic Leukemia with t(4;10) Showing Good Response to Imatinib Mesylate

A 38-year-old Japanese man was referred to our hospital in June 2003 for treatment of acute respiratory failure with severe eosinophilia. Idiopathic hypereosinophilic syndrome had been diagnosed in 1994. However, karyotypic examination of bone marrow cells revealed that chromosomal translocation with t(4;10)(q12;p11) had occurred in 2000, and chronic eosinophilic leukemia was diagnosed. At admission, the patient's respiratory condition was extremely serious, and mechanical support was necessary. Despite treatment with steroid pulse therapy and cytarabine, the blood eosinophil count did not decrease, and the patient's respiratory condition worsened. After obtaining informed consent, we administered imatinib mesylate at a dose of 200 mg/day for 2 days and 100 mg/day for 3 days. The blood eosinophil count decreased dramatically over 5 days, and the patient's condition rapidly improved, such that the patient could be discharged. In this case, we performed molecular analysis using peripheral blood. The FIP1-like 1 (FIP1L1)-platelet-derived growth factor receptor alpha (PDGFRalpha) fusion transcript was found with the reverse transcriptase polymerase chain reaction analysis. In this case, eosinophilia was possibly caused by constitutive activation of tyrosine kinase produced by the FIP1L1-PDGFRalpha fusion transcript.