A Case of Eosinophilic Angiocentric Fibrosis With Palatal Fistulas.

Eosinophilic angiocentric fibrosis (EAF) is a rare, but benign, tumefactive lesion of the head and neck regions. It was initially discovered in 1983 but has recently been connected to the spectrum of immunoglobulin G4-related disease (IgG4-RD). It commonly presents with symptoms of nasal obstruction, structural deformities of the external nose, and involvement of the nasal septum and lateral nasal wall. Our patient presented with a saddle nose deformity, a septal perforation, and palatal fistulas. Laboratory testing for EAF is often negative for the presence of antinuclear cytoplasmic antibodies (ANCA). A definitive diagnosis of EAF can be made through histopathological analysis of the lesion. The appearance of "onion-skin" fibrosis with perivascular infiltration of primary eosinophils is pathognomonic for EAF. While there is a presence of ulceration tissue, EAF does not have any histological signs of necrosis. EAF is a very uncommon etiology of nasal obstructive symptoms; therefore, it is necessary to rule out more conventional pathologies. Even though it appears as a malignant process, it has an excellent prognosis. The common treatment modalities for an active lesion of EAF involve either surgical resection of margins alone or a combination of corticosteroids and resection. Rituximab has also shown benefits in the management of IgG4-RD as a corticosteroid-sparing treatment. Rituximab was chosen for treatment in our patient because surgical resection was not possible due to the absence of an active lesion. In this article, we provide a brief review of EAF and provide a unique case of EAF presenting with oronasal palatal fistulas.