Bullous pemphigoid Management

Bullous pemphigoid

Bullous pemphigoid is a chronic autoimmune blistering disease that primarily affects older adults. It is characterized by the development of tense, fluid-filled blisters (bullae) on normal or erythematous skin due to autoantibodies directed against proteins of the basement membrane zone that anchor the epidermis to the dermis.

Unlike pemphigus vulgaris, the blisters in bullous pemphigoid are tense and less likely to rupture, and mucosal involvement is uncommon. The disease is usually chronic with periods of remission and relapse. Early diagnosis and appropriate treatment reduce morbidity and improve quality of life.

Pathophysiology (Brief)

The main mechanism is autoimmune destruction of the basement membrane zone, particularly the hemidesmosomal proteins BP180 (type XVII collagen) and BP230.

This leads to:

• Separation of the epidermis from the dermis

• Formation of subepidermal blisters

• Inflammatory cell infiltration

• Intense itching and blister formation

Signs & Symptoms

Typical lesions include:

• Tense vesicles and bullae

• Severe itching (often precedes blister formation)

• Erythematous or urticarial plaques

• Healing without significant scarring

Common sites:

• Lower abdomen

• Groin

• Flexor surfaces of the arms

• Thighs

• Axillae

• Trunk

Other findings:

• Blisters remain intact for several days

• Mild mucosal involvement (less common)

• Negative Nikolsky sign

• Secondary bacterial infection following blister rupture

Diagnostic Criteria

Diagnosis is based on:

• Tense blisters on erythematous or normal skin

• Severe pruritus

• Characteristic histopathological findings

• Positive direct immunofluorescence demonstrating linear IgG and/or C3 deposition along the basement membrane zone

Investigations

Recommended investigations

• Skin biopsy

• Full blood picture (FBP)

• Liver function tests (LFTs)

• Renal function tests (RFTs)

Special investigations

• Direct immunofluorescence (gold standard)

• Indirect immunofluorescence where available

• ELISA for BP180 and BP230 antibodies where available

Monitoring

During prolonged immunosuppressive therapy monitor:

• Full blood count

• Liver function

• Renal function

• Blood glucose in patients receiving prolonged corticosteroid therapy

Treatment

Treatment aims to relieve itching, suppress autoimmune inflammation, promote healing of blisters, prevent relapse, and minimize treatment-related complications.

Non-pharmacological Treatment

• Maintain good skin hygiene.

• Protect intact blisters from trauma.

• Use non-adherent dressings over eroded areas.

• Avoid scratching to reduce skin damage.

• Maintain adequate nutrition and hydration.

• Promptly treat secondary bacterial infection.

• Regular follow-up to monitor treatment response and medication adverse effects.

Pharmacological Treatment

• Betamethasone cream/ointment (topical) — apply every 12 hours until improvement.

OR

• Clobetasol propionate cream/ointment (topical) 0.05% — apply every 12 hours until improvement.

AND

• Prednisolone (PO) 0.5–1 mg/kg once daily for 2 months, then gradually taper to the lowest effective dose.

AND (for extensive involvement)

• Methotrexate (PO) 7.5–20 mg once weekly for not less than 4 months

OR (steroid-sparing alternatives, specialist level):

• S: Methotrexate (PO) 10–15 mg once weekly for at least 4 months with folic acid.

• OR S: mycophenolate mofetil (PO) 1 g/day for at least 4 months.

• OR S: rituximab (IV) 375 mg/m² weekly for 4 weeks.

Complications

• Secondary bacterial skin infection

• Sepsis

• Fluid and electrolyte imbalance in extensive disease

• Adverse effects of prolonged corticosteroid therapy

• Relapse after treatment

• Reduced quality of life

Prevention

There is no known method of preventing bullous pemphigoid. However, complications can be reduced by:

• Early diagnosis and treatment

• Good skin care and wound management

• Avoiding trauma to the skin

• Regular monitoring during immunosuppressive therapy

• Prompt treatment of secondary infections

Patient counselling (Important)

• Bullous pemphigoid is an autoimmune disease and is not contagious.

• Treatment often requires several months and regular follow-up.

• Do not stop corticosteroids abruptly without medical advice.

• Keep blisters clean and protected to reduce the risk of infection.

• Seek medical attention promptly if fever, increasing redness, pus, or rapidly worsening skin lesions develop.