Is peripheral blood immunophenotyping useful to understand the etiology of Idiopathic Granulomatous?

The etiology of idiopathic granulomatous mastitis (IGM) has not been clearly established. However, autoimmunity has recently become popular in etiopathogenesis. We aimed to investigate the immunophenotyping of immune cells to help clarify the etiopathogenesis of the disease.

Patients with IGM and healthy volunteers were included in the study. Patients were divided into active and remission groups based on their disease status. The ratios of total T cells, helper T cells, cytotoxic T cells, natural killer cells, regulatory T cells, and monocyte subtypes were measured using flow cytometry. In addition, age, complete blood count for leukocyte, lymphocyte, neutrophil, and eosinophil counts, and the smoking status of all volunteers were evaluated.

A total of 33 volunteers, including 11 patients with active IGM, 10 patients with remission IGM, and 12 healthy volunteers, were included in the study. The neutrophil, eosinophil, neutrophil/lymphocyte, and non-classical monocyte values were significantly higher in IGM patients than in healthy volunteers. Additionally, the CD4⁺ CD25⁺ CD127^- regulatory T cell was significantly lower in IGM patients than in healthy volunteers. Furthermore, neutrophil, neutrophil/lymphocyte ratio, CD4⁺ CD25⁺ CD127^- regulatory T cells, and non-classical monocytes showed significant differences when IGM patients were divided into active and remission groups. IGM patients had higher smoking rates, but this was not statistically significant.

The changes in many cell types evaluated in our study were similar to the cell profiles of some autoimmune diseases. This could provide minor evidence to suggest that IGM is an autoimmune granulomatous disease with a local course.