Background: Eosinophilic angiocentric fibrosis
(EAF) and granuloma faciale
(GF) share several histopathologic features, including eosinophil-rich inflammation, microangiitis, and progressive fibrosis. Concurrent presentation of EAF and GF suggests a pathogenetic link between them.
To identify histologic findings that tell them apart and construe the pathogenetic mechanisms behind each morphologic variable, 14 immunohistochemical markers were used to study the cells subpopulations in 14 cases of GF and 3 cases of EAF.
Materials and Methods:
The lesions were classified according to their stage of development. The antibodies studied were: CD4, Foxp3, CD8, granzymes A and B, perforin, granulysin, CD20, CD56, CD68, ICAM-1, CD34, CD105, and 1A4.
The intensity of the sclerotic response and the density of 1A4-immunostained cells were significantly higher in EAF. In both diseases, CD68+
cells were the most numerous, followed by CD20+
, and CD4+
cells. About 30% of cells expressed ICAM-1. Among cells with cytotoxic granules, granulysin-positive cells were the most frequent.
Differences between GF and EAF were found to be mostly like due to anatomic site (usually skin of the face vs. sinonasal cavity) and stage of the disease development (usually earlier in cutaneous lesions because of their visibility). Innate and adaptive immunity, including B cells, T cells, and cytotoxic granules have a role in their pathogenesis