Scarring Alopecia in a 66-Year-Old Woman

Abstract

A 66-year-old female with no significant medical history, referred from a rural area, presented with a 1-week history of ocular pain associated with ipsilateral erosions and tense bullae involving the left scalp and periocular region. On examination, extensive areas of alopecia were observed on the majority of the scalp, with no visible follicular openings, along with erosions and tense bullae on the left side of the scalp and periocular area. No involvement of other body areas or mucous membranes was noted (Figures 1 and 2). Initially, the differential diagnosis included herpes zoster or lichen planus pemphigoides with Wolf's isotopic response. A comprehensive ocular examination by an ophthalmologist ruled out herpetic infection or other structural damage to the eye. Notably, the patient reported similar episodes in her twenties, which had resulted in cicatricial alopecia over large areas of the scalp. Considering the clinical findings and the diagnostic alternatives, an incisional biopsy was performed for histopathology, direct immunofluorescence (DIF), and the salt-split test (Figures 3 and 4).

Cicatricial alopecia refers to a group of disorders that cause permanent hair loss due to the destruction of hair follicles. It can be classified as primary, involving lymphocytic, neutrophilic, mixed, or nonspecific etiologies, or secondary, resulting from physical factors such as trauma, thermal or surgical damage. Among these causes, BPP is rarely found as a possible aetiology.

BPP is a rare autoimmune blistering disease considered a variant of mucous membrane pemphigoid (MMP). To date, 65 cases have been reported in the literature with histopathological confirmation and positive DIF [1-3]. BPP is characterised by chronic and recurrent subepidermal bullae that most commonly appear on the scalp and face, leading to secondary scarring and cicatricial alopecia. Mucous membrane involvement is reported in only about 22.2% of cases and tends to be mild [3-6].

Diagnosis is based on clinical and histopathological correlation, with findings of subepidermal blisters and superficial dermal infiltrate containing eosinophils, along with DIF showing IgG and C3 deposits along the BMZ [3, 4]. When available, serologic studies such as indirect immunofluorescence and ELISA can help to confirm the diagnosis by identifying autoantibodies with specific target antigens [7]. If serologic tests are not available, the salt-split test can be a useful tool in DIF [7]. This test helps determine whether antibodies are binding to the epidermal or dermal side of the BMZ, providing information about the possible targeted antigens, which is not possible with DIF alone [7]. The pattern of antibody deposits in the BMZ, along with the salt-split test, helps identify the specific antigens involved; distinguishing between n-serrated and u-serrated patterns, and determining whether binding occurs on the epidermal or dermal side of the BMZ [8, 9]. BP180 and BP230, the antigens commonly involved in BPP, are located in the epidermal side of the BMZ and exhibit an n-serrated pattern. In contrast, other bullous diseases, such as epidermolysis bullosa acquisita (EBA), involve collagen VII, which is found in the dermal side of the BMZ and displays u-serrated pattern [7-10]. This differentiation aids in diagnosis [3, 6, 8]. There has been controversy over whether BPP is a variant of cicatricial pemphigoid or EBA. Recently it has been established that when BP180 or BP230 is the target antigen, it is classified as BPP, whereas if collagen VII is affected, it is considered BPP-like EBA [3, 9]. In our case, antibodies were detected on the epidermal side of the BMZ in the salt-split-test, indicating that the antigens involved corresponded to BP-180 or BP-230.

For treatment, topical high-potency steroids are typically used as the first-line therapy. However, a multimodal approach may be necessary to achieve lesion improvement. Immunomodulatory and immunosuppressive therapies such as methotrexate, azathioprine, tetracycline, dapsone or cyclosporine have been described, offering an adequate safety profile and leading to complete remission of lesions [3]. In our case, initial treatment with prednisolone 0.5 mg/kg/day and topical clobetasol resulted in significant improvement of lesions. Maintenance therapy with oral methotrexate at 15 mg/week, along with gradual corticosteroid tapering, led to complete healing of the skin lesions, with no evidence of new lesions.

BPP should be considered as a differential diagnosis in cases of cicatricial alopecia. It is important to correlate the patient's medical history, enquire about recurrences, and review physical examination findings, as well as biopsy and DIF reports. If serologic autoantibody identification is not available, the salt-split test serves as a useful and cost-effective diagnostic tool. This is the third reported case of BPP in a Hispanic female patient.

All authors contributed to the manuscript conception, design, drafting and revision of the article. All authors read and approved the final manuscript. All authors take responsibility for the integrity of the data and the accuracy of the data.

The project was reviewed and approved by the Ethics and Research Committee of the hospital, in accordance with applicable ethical guidelines. All patients in this manuscript have given written informed consent for participation in the study and the use of their de-identified, anonymized, aggregated data and their case details (including photographs) for publication.

The authors declare no conflicts of interest.