Case Number : Case 2696 - 05 November 2020 Posted By: Saleem Taibjee

hair follicles  show terminal hairs, hairs showing follicular miniaturization and some hair follicles in telogen/catagen phase. there is fibrosis around follicles with lymphocytes

Alopecia areata

Alopecia areata

I wish I saw a swarm of bees, but: 1) I guess this isn’t the acute phase 2) I’m sure I’m not familiar with this pathological chapter. So I agree with Colleagues. 

A few more images taken from additional levels, as well as CD3

Alopecia Areata

Hi. Yes this is alopecia areata (and correlates with the clinical description of patchy hair loss). I really like this recent case because it is presumably a semi-acute stage, and combines so many of the textbook features of AA in one biopsy.

In the initial images at the level of subcutaneous fat/dermis interface, as others have pointed out, the low-power clue is the combination of miniaturisation with hair cycle shift (with increased number of catagen and telogen follicles). We also see a subtle peri-bulbar lymphocytic infiltrate, and this is then nicely highlighted by the subsequent CD3. There are not really any other good explanations for peri-bulbar inflammation.

The additional levels are at higher levels in the biopsy, and show other features such as pigment casts (not entirely specific for AA, but nonetheless a feature). There is also a combination of miniaturisation, as well as an odd cornification evident within some follicles (but failing to produce hair shafts). The papers suggest that this is likely to be as a result of rapid and abnormal hair cycling (anagen-catagen-telogen) in AA, and can be termed as ‘nanogen’ follicles. Such follicles correspond to empty infundibula or yellow dots on dermoscopic examination.

Of course, this is a good illustration of how horizontal sections can facilitate assessment of non-scarring alopecia.