Method: Clinical and laboratory data from 25 patients with IHES or HE, US, seen between January 2004 and December 2014 at Hallym Sacred Heart Hospital, were collected retrospectively after chart review.
Result: A total of 25 patients were enrolled; 7 patients (28.0%) were diagnosed with HE, US and 18 patients (72.0%) with IHES. The mean number of white blood cell and peak total eosinophil count (TEC) were significantly increased in patients with IHES, compared to those with HE, US (p=0.008, respectively). Fip1-like1–platelet-derived growth factor receptor a (FIP1L1-PDGFRA) mutation analysis was done in 9 of 25 patients using in situ hybridization, and all showed negative results. In patients with IHES, the most common clinical presenting symptom was gastrointestinal (44.4%), followed by constitutional symptoms (33.3%) such as fever, myalgia, weakness, and weight loss, and pulmonary (11.1%). All patients received corticosteroids (0.25~1.0 mg/kg) as initial therapy. Seven patients (38.8%) showed complete response and 11 patients (61.1%) with partial response within a month. However, 9 patients (50.0%) recurred during tapering or discontinuation of corticosteroid. There was no significant association between treatment response and laboratory parameters including peak TEC, total IgE, eosinophil cationic protein or marrow eosinophilia.
Conclusion: The majority of patients with IHES respond to corticosteroid therapy, however, discontinuation of corticosteroid is associated with recurrence. There are no clinical or laboratory markers to predict the prognosis of IHES.