Rituximab-induced leukocytoclastic vasculitis in a patient with low-grade orbital B-cell lymphoma: a case report.

Rituximab is an anti-CD20 chimeric murine/human mAb mainly used to treat certain types of lymphoproliferative malignancies and autoimmune diseases. Although it has been used in the treatment of vasculitis in recent years, it rarely triggers severe vascular skin reactions such as leukocytoclastic vasculitis (LCV). Physicians should be aware of this rare adverse event that requires discontinuation of rituximab, which can occur days or even weeks after rituximab treatment. Here, we report a case of LCV observed in a patient with low-grade orbital B-cell lymphoma treated with weekly rituximab and local radiotherapy. In our case, discontinuation of rituximab and initiation of oral methylprednisolone therapy were sufficient to achieve complete resolution of the LCV.