Mucous Membrane Pemphigoid

Pemphigoid is a group of rare, debilitating autoimmune blistering diseases that can primarily affect the skin (bullous pemphigoid) or mucous membranes (mucous membrane pemphigoid). It may affect children and young adults, but it is most often found in older individuals of either sex.18 On some occasions blistering begins during or shortly after pregnancy (pemphigoid gestationis).10 Although the disease may begin on skin or mucous membranes, if untreated, it may spread to other areas of the body. On occasion pemphigoid is named according to the site of involvement (i.e., ocular pemphigoid and oral pemphigoid), and sometimes it is named according to the DIF location of immunoglobulin (i.e., linear IgA disease). Often oral mucous membrane pemphigoid (MMP) occurs as the first or only manifestation of the disorder with DG as the only noted clinical feature. However, the mucosa of the eyes, nose, genitalia and throat may be involved.3 Ocular MMP is one of the most devastating forms of the disease, and upon diagnosis of oral MMP it is very important to refer the patient to an ophthalmologist to rule out any ocular involvement. Older medical literature indicates that prior to development of relatively effective treatment modalities, many individuals with eye lesions would lose vision in one or both eyes due to progressive scarring.17,83 Scarring can also result in upper airway obstruction although scarring is very rare on oral mucosa.36 Occasionally, various medications (captopril, clonidine, furosemide, penicillamine, practolol and others) may trigger a pemphigoid-like process, but these lesions are far more common on skin.94

Oral MMP has a mean age of onset of 50 years, and it affects women slightly more often than men. Although lesions may be present on any oral mucosal tissue, the gingiva is usually involved (92.5%) and often DG is the only oral feature of the disease (62.3%).36 When possible, it is very important to perform H&E and DIF biopsy evaluation. Histologically MMP involves the basement membrane zone between the epithelium and connective tissue, and it is characterized by separation between the basal cells of the epithelium and the underlying connective tissue. A mild to moderate mixed inflammatory infiltrate is usually present in the lamina propria. DIF reveals a linear pattern of complement (C3) and immunoglobulin G (IgG) along the basement membrane zone. Occasionally IgM and/or IgA may be present in the linear pattern.

Figure 16. Mucous membrane pemphigoid and biopsy confirmation. DIF shows a linear deposit of IgG in the basement membrane zone.
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Figure 17. Severe MMP ocular lesion - danger of loss of vision.
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Therapy for oral MMP usually consists initially of topical or systemic corticosteroids as described previously. If topical steroids are used, a carrier tray is often beneficial.101 Systemic corticosteroids may be useful for short-term (2-3 week) treatment designed to achieve improvement in DG lesions, but this therapy is usually supplemented with or followed by topical agents. While complete remission is rarely achieved in managing MMP, it is often possible to improve patient comfort. Individuals with MMP that is resistant to a conservative but aggressive therapy should be referred to their dermatologist or internist for management with more potent therapeutic agents.

Figure 18. MMP before and MMP after successful treatment.
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ce481-fig18b-MMP-after-treatment

Maintenance of periodontal and dental health is important and can be achieved using the methods previously described. It may be of interest to note two studies have compared the periodontal health of individuals with treated MMP associated DG and age and sex matched control patients without MMP. In the first study, there were no significant differences in the incidence of periodontitis between the two groups.96 In a follow-up study, 5 years later involving half of the same MMP patients and their original age and sex matched controls, identical findings were evident. This appears to offer moderately strong evidence the improved oral health of individuals with treated oral MMP can result in the effective maintenance of periodontal and dental health.81