CLINICAL, SEROLOGICAL, IMMUNOLOGICAL AND HISTOPATHOLOGICAL CHARACTERIZATION OF PATIENTS WITH FIBROSING FRONTAL ALOPECIA
- Ingrid Ruiz-Ordoñez, Colombia
Abstract
Background and Aims
Frontal fibrosing alopecia (FFA) is a rare type of cicatricial alopecia. The specific mechanisms of development of FFA remain unknown. We previously proposed an autoimmune origin (Med Hypotheses2019;124). Here we describe the clinical and immunohistochemical profile of patients with FFA.
Methods
This was a retrospective cohort of 11 patients with FFA diagnosed by scalp biopsy. To evaluate the expression of immunological markers in 10 available scalp biopsies, we assessed by immunohistochemistry the following markers: B2 microglobulin, HLA class I and II, CD20, CD25, CD3, CD4, and CD8.
Results
All patients were female. Mean age at FFA diagnosis was 55.9 ± 9.51 years. Four (36.36%) patients had SS, and the same number had hypothyroidism. Five (45.45%) patients had positive antinuclear antibodies. In most of the samples, we observed expression of B2 microglobulin, HLA class I and II in the hair follicle. Only one (10%) patient showed CD20+ expression, while four (40%) patients presented infiltrating T lymphocytes (CD3+), including inverted relation among CD4/CD8 in two cases (20%). In 2 patients with SS, infiltrate expression was seen after 2- and 5-years of diagnosis. A patient with a recent diagnosis of SS did not show expression of any marker.
Conclusions
Our findings show a possible immune origin of FFA, represented by lymphocytic infiltration, expression of B2 immunoglobulin, HLA class I, and II causing impairment in the immune privilege of the hair follicle. The association of FFA with SS and hypothyroidism arises the possibility of an autoimmune origin.