Off-label omalizumab was safe and effective in our patients. The novel immunologic features recorded in our patients add further complexity to the mechanism of action of omalizumab.

UC patients frequently show several markers of allergy. In particular, our data suggest an association between ulcerative colitis, tissue eosinophilia, and type-I allergy.

Kaposi's sarcoma appeared on a chronically lymphedematous leg of a 75-year-old man. Immunologic investigations revealed a lack of cellular immune response confined to the involved lower limb. Regional disorders of immune surveillance are thought to play an important role in the early stages of Kaposi's sarcoma.

In UC patients, appendectomy and cigarette smoking are prognostic factors for the development of EIM. The unfavorable effect of cigarette smoking on EIM is additive to that of appendectomy.