Histopathologic profile of alopecia areata in Indian patients

Abstract

Background:Alopecia Areata (AA) is a “non-scarring” alopecia that has an autoimmune basis. Though clinically distinctive, problems arise in diagnosis depending on the temporal stage of the disease at presentation; some of them progress to scarring alopecia and predicting its prognosis is difficult. Histological changes depend on the disease stage and site of the biopsy.Objectives:To describe the spectrum of histologic features in AA.Materials and Methods:A prospective and retrospective study of H and E sections of all biopsies signed out as AA between 2001 and 2009 (20 cases) was undertaken.Results:The diagnosis was made on vertical sections in all cases. The total number of hair follicles ranged from 1 to 24 with an average of 7 and comprised mainly terminal follicles. Vellus follicles were scanty. Anagen to non-anagen ratio was 1:1.62. Miniaturization of follicles was noted in five (25%) cases. Peribulbar inflammation was seen in all the cases with a dominance of lymphocytes. Perifollicular fibrosis was noted in 12 (60%) and pigment casts in 5 (25%) cases. Scarring was seen in two cases. In these cases, a diagnosis of AA was rendered on the basis of even spacing of the fibrotic units and remnants of the catagenic basement membrane within the scars. The epidermis and interfollicular dermis were normal in all the cases.Conclusion:The most consistent features of AA are an increase in non-anagen terminal follicles and peribulbar lymphocytic infiltrate. The etiology can be determined even in cases that have progressed to scarring.

A comparison of vertical and transverse sections in the histological diagnosis of alopecia areata scalp biopsy specimens

“…There was slight female predominance with female:male ratio of 1.14:1 which was consistent with Chaitra et al . [ 4 ] As a classic AA is rarely biopsied, the pathologists have a limited experience in interpretation of biopsies of AA when clear-cut diagnostic features such as peribulbar lymphocytic infiltrate are not present. [ 4 ]…”

“…The role of a pathologist is vital when dealing with atypical presentations, such as patients progressing to scarring, use of topical medications that alter the picture, in trying to provide prognostic information. [ 4 ]…”

“…[4] AA progresses through acute, subacute, and chronic stages. [5] In the acute stage, there is inflammatory infiltrate around the terminal hair bulb, whereas in the chronic stage, there is a reversal of the terminal-vellus ratio.…”

“…The histologic changes vary depending on the stage of the disease and most pathologists have limited experience with their interpretation as classic AA is rarely biopsied. [ 4 ] AA progresses through acute, subacute, and chronic stages. [ 5 ] In the acute stage, there is inflammatory infiltrate around the terminal hair bulb, whereas in the chronic stage, there is a reversal of the terminal-vellus ratio.…”

Direct immunofluorescence pattern and histopathological staging in alopecia areata

“…[ 2 12 13 14 15 ] Histopathological features observed in the present study are consistent with the other studies. [ 2 3 15 16 17 ] Histopathologic features suggest an immune mechanism in the pathogenesis as all the clinically diagnosed cases of AA showed a variable degree of peribulbar lymphocytic infiltrate. Two cases showed presence of giant cells as observed in other studies.…”