Remission and recurrence of hyperthyroid Graves' disease during and after methimazole treatment when assessed by IgE and interleukin 13

We analyzed the relationship between serum IgE concentrations and the remis sion or recurrence of Graves' disease. One hundred seven patients with Grav es' disease were treated with methimazole (MMI). Serum IgE concentration gr eater than 170 IU/ml was found in 41 of 107 untreated patients (38.3%). How ever, the presence of TSH-binding inhibiting immunoglobulin or thyroid-stim ulating antibody did not correlate with the IgE concentrations. Remission w as found in 20 of 41 patients with elevated IgE concentrations (48.8%) afte r 18 months of MMI treatment, as opposed to 53 of 66 patients with normal c oncentrations (80.3%) (P = 0.0014). MMI treatment was discontinued in 73 pa tients who were followed for 26-48 months. The recurrence of Graves' diseas e was found in 13 patients, whereas the remaining 60 were still in remissio n. The rate of long-standing remission was lower in patients with elevated than normal IgE concentration (34.1% vs. 69.71%, P = 0.0007). We also analy zed serum levels of interleukin (IL)-13. Although IL-13 was not detected in all patients, the detection rate was higher in patients without remission and in those with recurrence than in those with long-standing remission (47 .1%, 38.5%, and 13.3%, respectively; P = 0.0012). More patients with elevat ed IgE were positive for allergic diseases and for family history of allerg ic diseases in their first-degree relatives. We conclude that the elevation of IgE and the higher detection rate of IL-13 are associated with both rem ission and recurrence of Graves' disease.