Alopecia in Systemic Amyloidosis: Trichoscopic-Pathologic Correlation

Abstract

Alopecia in systemic amyloidosis is very rare and has been described as individual cases of diffuse nonscarring alopecia and a case of alopecia universalis. We report the trichoscopic findings in alopecia associated with systemic amyloidosis. The most prominent feature was a salmon colored halo (0.3-1 mm in diameter) surrounding the follicular ostia. Other features included broken hairs and black dots. The salmon colored halo correlated on pathology with the perifollicular deposition of amyloid. The horizontal sections showed that the sebaceous glands were preserved which supports the nonscarring pattern of the alopecia.

INTRODUCTION

Alopecia in systemic amyloidosis is very rare and has been described as individual cases of diffuse nonscarring alopecia[1,2,3,4] and a case of alopecia universalis.[5] We report an unusual case of systemic amyloidosis with diffuse nonscarring alopecia, milia, and nail dystrophy and focus on the trichoscopic findings of the alopecia and their pathologic correlation on horizontal sections.

CASE REPORT

A 65-year-old man presented with a 2-year history of progressive hair loss involving the scalp, the eyebrows and the upper trunk, and recent onset of small papules and blisters on the dorsal hands as well as longitudinal ridging and fissuring of the fingernails. Clinical examination showed diffuse alopecia most pronounced on the androgen dependent scalp; the skin was slightly indurated on palpation [Figure 1a]. There were focal petechiae. The lateral sides of both eyebrows and most of the hair on the chest were absent too. The axillary, pubic, and limb hair was preserved.

Figure 1.

(a) Alopecia of the scalp with focal petechiae. Note diffuse thickening of the skin; (b) trichoscopy in the alopecic area shows decreased hair density with presence of follicular openings. Note pink - orange/salmon colored halos surrounding all follicular structures, including empty follicles, black dots and broken hairs (Handyscope FotoFinder Systems, ×20)

Trichoscopic examination of the scalp showed prominent salmon colored halos (0.3-1 mm in diameter) surrounding the follicular ostia [Figure 1b]. These halos were seen around empty follicles as well as around follicles containing terminal and vellus hairs, black dots, and/or broken hairs. This trichoscopic finding was present over the entire scalp.

A 4 mm punch biopsy from the alopecic scalp was obtained and bisected in horizontal sections. There was overall preserved follicular architecture with intact sebaceous glands [Figure 2a]. There were no terminal anagen follicles, one terminal telogen follicles, two vellus anagen follicles and 10 atrophic follicular structures reminiscent of telogen germinal units (secondary germs). All follicular structures were surrounded by amorphous eosinophilic material, which formed either a compact- or loosely- folded fibrillar cast [Figure 2b]. The same material was deposited in all fibrous streamers, which appeared eosinophilic, homogenized and avascular. Congo red stain evaluated under polarized light highlighted the apple green stain of the amyloid [Figure 2c].

Figure 2.

(a) Horizontal sections through the isthmus level reveal overall preserved follicular architecture and preserved sebaceous glands. Note the absence of terminal follicles and the presence of atrophic germ like follicular structures surrounded by eosinophilic amorphous material (H and E, ×4); (b) an atrophic follicular structure reminiscent of secondary follicular germ (telogen germinal units) surrounded by compact amorphous esionophilc material outlined as a cast (H and E, ×40); (c) congo red stain under polarized light highlights the apple birefringence of the amyloid in the dermis (red arrows). Normal collagen, as an in-built control remains yellow under the polarized light (blue arrows)

Serum electrophoresis and bone marrow biopsy established the diagnosis of multiple myeloma.

COMMENT

Alopecia is a less recognized cutaneous presentation of systemic amyloidosis as <20 cases have been reported so far.[4] In most reports, it preceded the diagnosis of systemic amyloidosis by up to 6 years[1,2,3,5] and presented as patchy or diffuse nonscarring progressive thinning of the scalp. Only one report of alopecia universalis associated with systemic amyloidosis exists.[5]

Trichoscopy of alopecia associated with systemic amyloidosis shows a nonscarring pattern, with dystrophic hairs, black dots, and broken hairs. These features are not specific as they are also seen in alopecia areata, chemotherapy induced alopecia, trichotillomania and early dissecting cellulitis of the scalp.[6,7] A new and characteristic finding is the presence of a salmon colored halo around the follicular structures that correlate on pathology with the perifollicular deposition of amyloid.

Histopathologic findings of amyloidosis associated alopecia have been described on vertical sections as a follicular loss with absent sebaceous glands[1] and amorphous, eosinophilic material around follicular structures and vessels.[3] Our findings are most close to the description by Hunt et al.[2] They found empty follicular sheaths associated with persistent telogen structures (telogen germinal units) and only a few remaining anagen follicles.

Our horizontal sections allowed showing that in alopecia of systemic amyloidosis the sebaceous glands are preserved, which confirms its nonscarring nature. The atrophic follicular structures compressed by the surrounding amyloid correspond to the dermatocopic finding of dystrophic hairs surrounded by a salmon colored halo. These structures are morphologically similar to the follicular germs (telogen germinal units) described in other alopecias characterized by deposition in the skin such as linear morphea alopecia[8] and follicular mucinosis associated alopecia.[9,10] These findings support the concept that mechanical constriction to the follicles caused by abnormal follicular or perifollicular deposition of amyloid, collagen or mucin may lead eventually to anagen arrest.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest