Definition
Bullous pemphigoid is an autoimmune skin condition that occurs primarily in older adults, which is characterized by blisters and/or erosive lesions of the skin or mucosa.
Incidence
Most cases occur in adults older than the age of 60 years. Studies show that during 2000 to 2005, the incidence of bullous pemphigoid was approximately 22 cases per million people, which is three times greater than in previous years.
Pathogenesis
A.The mechanism of the physiological changes that occur in the body to cause bullous pemphigoid is not fully understood. It is believed to be an autoimmune disorder, driven by autoantibody-mediated effects that cause damage to the epithelial basement membrane. Antibodies attach to the antigens on the basement membrane, causing inflammatory changes, resulting in separation of the epidermis from the dermis in the skin and separation of the epithelium from the subepithelial tissue in the mucous membranes, producing blister lesions on the affected tissues.
Predisposing Factors
A.Age (adults older than 60 years).
B.Exposure to certain medications (penicillin, etanercept [Enbrel], sulfasalazine [Azulfidine], and furosemide [Lasix]).
C.Ultraviolet (UV) light and radiation therapy.
Common Complaints
A.Large, tense blisters commonly located on the arms, legs, or trunk. Commonly seen along skin folds/creases.
B.Blisters may be asymptomatic or may be erythemic and pruritic.
Other Signs and Symptoms
A.Irritation to the oral mucosa, mouth sores, and/or bleeding gums.
B.Rash in addition to skin blisters.
C.Changes in mucous membranes of the eyes, noting redness and discomfort.
Potential Complications
A.Bacterial skin infection.
B.Sepsis.
C.Scarring of the mucous membranes in the mouth or eye.
Subjective Data
A.Ask patient if there was any precipitating event prior to the outbreak of the blisters.
B.Have patient describe when the blisters began and the duration of the blisters.
C.Ask patient to describe the onset of the presenting lesions and the progression of the lesions.
D.Ask if the blisters are painful. If so, describe pain, such as stabbing, burning, throbbing, and so on.
E.Rate pain on a scale of 0 to 10, with 0 being no pain.
F.List all medications currently being taken, particularly substances not prescribed. Did the blisters begin after the initiation of any new medications?
Physical Examination
A.Assess vital signs: Check temperature, pulse, respirations, and blood pressure.
B.Inspect:
1.Inspect general appearance of the skin, noting types of blisters/lesions. Note the location of the blisters, along with erythema, inflammation, or weeping. Inspect skin folds carefully.
2.Inspect the blisters for stages of the blister.
3.Inspect oral cavity for oral lesions.
4.Perform ophthalmologic exam: Inspect eyes for erythema, edema, and ulcers.
Diagnostic Tests
A.Biopsy: Skin lesion biopsy for staining and for direct immunofluorescence (DIF) studies. The gold standard for diagnosis is a positive DIF.
B.Blood tests: Peripheral blood smear. Elevated eosinophils and increased immunoglobulin G (IgG) levels may be present.
Differential Diagnosis
A.Bullous pemphigoid.
B.Cellulitis.
C.Dermatitis.
D.Shingles.
Plan
A.General interventions:
1.Promote healing of blisters and prevent secondary bacterial infection.
2.The goal of treatment is to control blister formation.
B.Patient teaching:
1.Inform patient regarding the course of bullous pemphigoid. This skin condition may last for months or years. Therefore, treatment options are variable for all patients.
2.Advise the patient to avoid sun exposure directly on the skin.
3.Skin care: Educate the patient regarding taking care of the fragile skin, avoiding injury to all sites. Tense blisters should be cleansed well with alcohol and carefully ruptured with a sterile needle. The overlying tissue from the blister should remain intact to act as a natural wound cover. Open sores should be covered with a nonadherent bandage to reduce the risk of infection.
4.Oral blisters should be protected by avoiding spicy or hard foods that would cause more injury to the oral ulcers.
C.Pharmaceutical therapy:
1.First-line therapy suggested is topical steroids. Topical steroids, such as clobetasol propionate 0.05% cream, are applied to the affected area BID until inflammation, new blister formation, and pruritus have resolved for at least 2 weeks. Then gradually taper the steroid cream over the next few weeks to months.
2.If the topical steroids are not successful, oral steroids may be used. Prednisone 0.5 to 0.75 mg/kg/d may be used as a starting dose. Oral prednisone is used until inflammation, new blister formation, and pruritus have resolved for at least 2 weeks. Then gradually taper the prednisone over the next several weeks to months.
3.In severe cases, immunosuppressants may be prescribed to help control the lesions. These medications may include methotrexate, azathioprine (Imuran), and mycophenolate mofetil (Cellcept). Using these medications may also allow weaning of the use of corticosteroids.
4.Medications with anti-inflammatory effects may also be used, such as tetracycline and dapsone.
5.Antibiotics and niacin may be prescribed for signs of bacterial infection. Tetracycline antibiotics may be used for mild cases. Niacin may also be prescribed, along with tetracycline, to help control gastrointestinal side effects:
a.Patients who do not respond to steroid treatments may be prescribed biologic therapy such as intravenous (IV) rituximab.
Follow-Up
For patients on oral or topical treatments, recommend a follow-up appointment in 1 to 2 weeks, depending on the presentation. If signs of bacterial infection are present, then follow-up would need to be sooner.
Consultation/Referral
A.Consult with the physician or the dermatologist for all patients who present with signs of bullous pemphigoid for treatment options.
B.Consult with the physician if signs of bacterial infection are present. In severe cases, sepsis can develop and become life-threatening for compromised patients.
C.The physician or the dermatologist should prescribe potent medications, such as immunosuppressants.
D.Refer any patient who presents with any eye involvement to the ophthalmologist.
Individual Considerations
A.Pregnancy: Rarely seen in this population.
B.Geriatrics:
1.Most commonly seen in adults older than 60 years of age. Patients who are compromised or in poor health may develop a secondary bacterial infection, which can be life-threatening.
2.Studies suggested that eczematous dermatitis in the elderly population are possibly early indications of a bullous pemphigoid outbreak. Because the disease is closely associated with neurogenerative diseases, consider collaboration with a neurologist and dermatologist for treatment management.
3.Recommendations for treating elderly with bullous pemphigoid:
a.First-line clobetasol propionate 0.025% cream topically (except the face).
b.Second-line tetracycline and nicotinamide combination therapy.
c.Third-line PO dapsone or PO/SQ methotrexate weekly.
d.Discontinue therapy if clinical remissions last a minimum of 6 weeks and patient has a negative immunofluorescence test.