How should I manage a patient with a 20‑year history of bullous skin lesions that rupture and form erosions, now presenting with extensive erosions on the back of the chest?

Management of Chronic Bullous Disease with Extensive Erosions

For a patient with a 20-year history of bullous lesions now presenting with extensive erosions on the back and chest, this clinical picture is most consistent with bullous pemphigoid (BP), and you should initiate treatment with superpotent topical corticosteroids (clobetasol propionate 0.05% cream 30-40g daily) applied to the entire body surface, or alternatively systemic corticosteroids (prednisone 0.5-0.75 mg/kg/day) if topical therapy is not feasible. 1

Diagnostic Confirmation

Before initiating treatment, confirm the diagnosis with:

• Direct immunofluorescence (DIF) of perilesional skin showing linear IgG and/or C3 deposits at the basement membrane zone
• Indirect immunofluorescence or ELISA for anti-BP180 and anti-BP230 antibodies
• Complete blood count, metabolic panel, liver function tests
• Screen for underlying malignancy and infections (particularly tuberculosis) if immunosuppression is planned
• Consider osteodensitometry and ophthalmologic examination if long-term systemic steroids are anticipated 1

First-Line Treatment for Extensive Disease

Topical Corticosteroid Regimen (Preferred)

Clobetasol propionate 0.05% cream or ointment:

• Initial dose: 30-40g daily (20g if weight <45kg)
• Application: Twice daily to entire body including normal skin, blisters, and erosions; spare the face
• Disease control definition: When new lesions cease forming and established lesions begin healing (typically 1-3 weeks)
• If no control within 1-3 weeks: Increase to 40g daily if currently using less 1

Tapering schedule after achieving disease control:

1. Daily application for first month
2. Every 2 days in second month
3. Twice weekly in third month
4. Once weekly starting fourth month
5. After 4 months, either continue maintenance (10g once weekly for 8 additional months) or stop treatment 1

Systemic Corticosteroid Alternative

If topical therapy is impractical (patient unable to apply, lacks caregiver support):

• Prednisone 0.5-0.75 mg/kg/day (NOT 1 mg/kg—higher doses associated with increased mortality compared to topical therapy)
• Taper 15 days after disease control achieved
• If no control within 1-3 weeks, increase to 0.75 mg/kg/day
• Target minimal therapy (0.1 mg/kg/day) within 4-6 months 1, 2

Critical caveat: Systemic steroids at 1 mg/kg have shown higher mortality and side effects compared to whole-body topical clobetasol in elderly BP patients, making topical therapy the superior first choice when feasible 1

Adjunctive Wound Care

For extensive erosive lesions:

• Antiseptic baths containing antiseptics and/or wheat starch
• Non-adherent dressings over erosions to reduce bacterial superinfection, minimize pain, and promote healing
• Monitor for secondary bacterial infection with local bacteriological sampling if clinically indicated 1

Second-Line Options for Refractory Disease

If disease control is not achieved or patient relapses on unacceptably high doses:

Add or switch to:

• Azathioprine 1-2.5 mg/kg/day (check thiopurine methyltransferase first)
• Mycophenolate 0.5-1g twice daily
• Tetracycline + nicotinamide 500-2500mg daily (safer for patients with diabetes/hypertension)
• Methotrexate 5-15mg weekly
• Dapsone 50-200mg daily (check G6PD first) 1, 2

Differential Consideration

While BP is most likely given the chronic relapsing course and age, epidermolysis bullosa (EB) should be considered if:

• Symptoms began in childhood/infancy
• Family history of blistering disorders
• Mucosal involvement is prominent
• Scarring and milia formation are present

However, the 20-year duration with apparent survival and lack of mention of childhood onset makes inherited EB less likely. EB would require entirely different management focused on wound care, multidisciplinary support, and prevention of complications rather than immunosuppression 3, 4, 5

Monitoring and Relapse Management

Relapse definition: New blisters, eczematous lesions, urticarial plaques >10cm diameter not healing within 1 week, or daily pruritus after achieving disease control 1

If relapse occurs:

• Localized relapse: 10g clobetasol daily to affected areas
• Mild disease: 20g daily
• Extensive relapse: 30g daily 1

The key distinction in this case is recognizing that extensive erosive disease requires aggressive initial therapy with either whole-body topical superpotent steroids or systemic corticosteroids, with topical therapy being safer and more effective in the elderly population that typically develops BP.