Granulomatous Lymphangiitis (Melkersson‐Rosenthal Type)

A 33‐year‐old Caucasian female presented with a ten‐year history of flushing and facial swelling partially responsive to anti‐inflammatory and anti‐microbial therapies. Progressive edema of the right upper eyelid was recently treated by blepharoplasty. The blepharoplasty specimen had a dense mononuclear inflammatory infiltrate and diffuse non‐caseating granulomas composed of epithelioid and multinucleated histiocytes. The granulomas appeared both peri‐and intralymphatic with prominent molding. Special stains and polarization studies were negative. To confirm the intralymphatic location of these granulomas we performed immunohistochemical staining with Factor VIII and D2–40. D2–40 is a new monoclonal antibody that reacts with an O‐linked sialoglycoprotein found on lymphatic endothelium, fetal testis, and on the surface of testicular germ cell tumors. In recent studies, clone D2–40 has shown staining in lymphatic channel endothelium but not in adjacent capillary. Factor VIII antibody highlighted both lymphatic and blood vessel endothelium, while D2–40 stained only the lymphatic endothelium and confirmed the intra‐lymphatic location of granulomas. The patient was diagnosed with granulomatous lymphangiitis of the Melkersson‐Rosenthal type (orofacial granulomatosis). Granulomatous lymphangiitis is characteristic but not completely diagnostic of the Melkersson‐Rosenthal syndrome. We present the complex differential diagnosis of intralymphatic granulomas and the use of a new monoclonal antibody helpful in verifying their location.