[Eosinophilic angiocentric fibrosis: a form of IgG4-related systemic disease?].

Eosinophilic angiocentric fibrosis is a rare fibro-inflammatory disorder of unknown etiology with only 40 cases reported in the literature. It primarily affects the sinonasal tract and more rarely the orbit, the larynx and the gums. This benign disorder is characterized by a slowly progressive process mimicking a tumor, with frequent recurrences after surgical excision and cortico-therapy. The typical histology consists of fibro-inflammatory lesion with numerous eosinophils, arranged in a perivascular pattern. As the lesion matures, inflammation becomes less intense and the fibrosis progresses with an onion-skin type perivascular fibrosis. A recent paper suggests that EAF is part of the spectrum of IgG4-related systemic disease. We report a case of orbital EAF in an 86-year-old woman which sustained this hypothesis.