Alopecia in Autoimmune Blistering Diseases: A Systematic Review of Pathogenesis and Clinical Features of Disease

Abstract

<b><i>Background:</i></b> Autoimmune blistering diseases (AIBD) are characterised by the body’s production of autoantibodies against structural proteins in the epidermis and/or the basement membrane on cutaneous and mucosal surfaces. Alopecia is a complication of AIBD that has generally been overlooked in patients with severe blistering diseases because it is regarded as a cosmetic issue. Yet recent research into quality of life tools has found that stigmatisation by appearance plays a significant role in blistering diseases. <b><i>Aim:</i></b> To review the current literature detailing the pathogenesis and clinical presentations of alopecia in AIBD patients. <b><i>Method:</i></b> We searched Medline, PubMed and EMBASE electronic databases up to September 2018, for empirical human and animal studies. <b><i>Results:</i></b> Only 36 human studies including 223 patients (190 pemphigus, 25 pemphigoid, 5 epidermolysis bullosa acquisita, 2 dermatitis herpetiformis and 1 linear IgA disease) detailed demographic and clinical manifestations of alopecia. A range of hair evaluation methods was demonstrated to reach alopecia diagnosis. Furthermore, with no universal validated scoring system for alopecia severity, alopecia patterns have been summarised. <b><i>Conclusion:</i></b> Previous randomised trials have not highlighted alopecia as an important outcome of AIBD, so epidemiological evaluation of the available literature has been helpful in summarising trends between existing studies and demonstrating inconsistencies.

Extension of separation along the follicular epithelium and follicular basement membrane in pemphigus and bullous pemphigoid

“…Similar to PV, follicular extension in BP was readily The reduced expression of all BMZ components outside the hair bulb and the complete absence of BP230 at the dermal papilla had been reported. [25][26][27][28] In a single case report of BP, immunofluorescence studies showed deposition of IgG at the dermoepidermal junction around the hair follicle epithelium of deep dermal hair follicles. 29 In another publication, extrusion of a sebaceous lobule with part of the hair follicle attached to it lying inside the blister cavity in a case of BP had been noticed.…”

“…30 Follicular involvement in BP could be of clinical significance providing a possible explanation for alopecia reported in some BP cases, also for scalp localization and scarring in Brunsting-Perry cicatricial pemphigoid and some cases of mucous membrane pemphigoid. 26,31 Plucked anagen hair, an easily obtained accessible substrate, was used successfully as a substitute for perilesional skin biopsy in DIF for diagnosis of pemphigus. 23,24 Given the high incidence of follicular BM extension in BP in the present study, hair follicles could be of help in diagnosis of BP in the same way as in the pemphigus group.…”

Cicatricial pemphigoid Brunsting–Perry variant masquerading as neutrophil‐mediated cicatricial alopecia

“…A recent systematic review of alopecia in autoimmune blistering diseases showed that Brunsting-Perry pemphigoid seems to be consistently associated with non-specific scarring alopecia. 8 Neutrophils constitute the dominant infiltrate in some autoimmune blistering diseases including neutrophil-rich variants of cicatricial pemphigoid and bullous pemphigoid, epidermolysis bullosa acquisita, bullous lupus erythematosus, linear IgA bullous disease, and dermatitis herpetiformis. 1,9,10 There are reports of scarring alopecia presenting in conjunction with all of the mentioned diagnoses, except for dermatitis herpetiformis, which is associated with alopecia areata.…”

“…1,9,10 There are reports of scarring alopecia presenting in conjunction with all of the mentioned diagnoses, except for dermatitis herpetiformis, which is associated with alopecia areata. 8 Additionally, perifollicular cleft formation can be found in association with folliculitis decalvans and lichen planopilaris adjacent to perifollicular inflammation and fibrosis. 11 It has been suggested that clefting in these conditions is because of dense inflammation causing thinning of follicular epithelium, squamatization of the basal layer, and fibrous tissue contraction.…”

Scalp Erosions that Do Not Heal: The Diagnostic Value of Trichoscopy

“…According to the literature, scalp involvement is the first location in around 10% of cases [1]. Besides erosions, patchy alopecia and anagen shedding are also a possible presentation of the disease in the scalp area [2, 3].…”