Periorbital necrobiotic xanthogranuloma successfully treated with intravenous immunoglobulin

Background: Necrobiotic xanthogranuloma (NXG) is a rare non-Langerhans histiocytosis with cutaneous manifestations, most commonly of the periorbital skin, and is often associated with hematologic disorders such as monoclonal gammopathy. Treatment of NXG is notoriously difficult, and fraught with recurrence and progression. Case Presentation: The authors describe a case of NXG with periorbital involvement in a patient with a complex autoimmune and hematologic medical history. The biopsy of this rare lesion prompted subsequent evaluation for an underlying disorder, which led to the diagnosis of multiple myeloma. Her NXG lesions demonstrated remarkable clinical improvement after treatment with intravenous immunoglobulin (IVIG). Conclusions: This case demonstrates the ophthalmologist's critical role in the diagnosis and management of NXG, as early detection cannot only prevent ophthalmic consequences such as ocular perforation and blindness, but also prompt further investigation that may reveal an underlying disorder or systemic involvement, including hematologic malignancy as in this case. NXG has been effectively treated with IVIG in a handful of reported cases. To the author's knowledge, this is the third case of periorbital NXG successfully treated with IVIG, and the first in the ophthalmic literature.