Can psoriatic lesions in patients with severe psoriasis and a history of full thickness and ulcerated lesions respond to topical steroid cream, such as clobetasol (clobetasol propionate) 0.05% cream?

Psoriatic Lesions: Full-Thickness Ulceration and Steroid Response

Classic psoriatic lesions do not ulcerate through full-thickness skin—if you see ulceration, you are dealing with a different diagnosis or a complicating factor (infection, malignancy, pyoderma gangrenosum, or vasculitis), and topical steroids alone will not adequately treat true ulcerated lesions. 1

Understanding Typical Psoriatic Morphology

Psoriasis presents as well-demarcated, erythematous plaques with overlying silvery scale, not as ulcerated wounds. 1 The characteristic lesions include:

• Thick, indurated plaques with scale on extensor surfaces (elbows, knees), scalp, trunk, and umbilicus 1
• Inverse psoriasis in intertriginous areas appears as erythematous, minimally indurated, non-scaling plaques—but still without ulceration 1
• No erosions or ulcers are part of the typical psoriatic presentation 1

When Ulceration Occurs: Red Flags

If you observe full-thickness ulceration in what appears to be a psoriatic distribution, you must consider:

• Secondary infection (bacterial superinfection requiring antimicrobial therapy) 1
• Pyoderma gangrenosum (often misdiagnosed as infected psoriasis)
• Malignancy (squamous cell carcinoma can arise in chronic plaques)
• Vasculitis or ischemic ulceration (particularly in patients with psoriatic arthritis)
• Severe immunotherapy-related psoriasiform eruptions with erosions (though these are erosions, not full-thickness ulcers) 1

A biopsy and wound culture should be obtained before assuming topical therapy will suffice. 1

Topical Steroid Efficacy in Standard Psoriasis

For non-ulcerated psoriatic plaques, high-potency topical steroids like clobetasol propionate 0.05% are highly effective:

• Clobetasol 0.05% cream or ointment achieves 68-81% clear or almost clear status after 2 weeks in thick, chronic plaques 2, 3, 4
• Apply twice daily for 2-4 weeks maximum (not to exceed 50 grams weekly) to avoid HPA axis suppression 2, 5
• Use only on trunk, limbs, and scalp—never on face, genitals, or intertriginous areas due to atrophy risk 2

Why Topical Steroids Fail in Ulcerated Lesions

Topical corticosteroids work by:

• Suppressing inflammation in intact epidermis and dermis 1, 2
• Reducing keratinocyte proliferation and immune cell infiltration 1

In full-thickness ulceration:

• The epidermal barrier is completely absent, eliminating the target tissue for steroid action
• Wound healing requires granulation tissue formation, re-epithelialization, and infection control—none of which are promoted by corticosteroids
• Topical steroids can actually impair wound healing and increase infection risk in open wounds 5

Appropriate Management Algorithm

For Thick Psoriatic Plaques (No Ulceration):

1. Clobetasol propionate 0.05% cream/ointment twice daily for 2-4 weeks 2, 3
2. Transition to calcipotriene or calcipotriene/betamethasone combination for maintenance (safe up to 52 weeks) 2, 4
3. Taper frequency gradually rather than abrupt discontinuation to prevent rebound 2

For Suspected Ulcerated "Psoriatic" Lesions:

1. Stop topical steroids immediately and obtain dermatology consultation 1
2. Perform wound culture and biopsy to rule out infection, malignancy, or alternative diagnosis 1
3. Initiate wound care with appropriate dressings and antimicrobials if indicated
4. Consider systemic therapy (biologics, methotrexate, cyclosporine) for severe psoriasis with complications 1

Critical Safety Warnings

Common adverse effects of clobetasol include:

• Skin atrophy, striae, telangiectasia, purpura (especially on face, forearms, and intertriginous areas) 2, 5
• HPA axis suppression with prolonged use beyond 4 weeks 2, 5
• Burning/stinging (occurs in approximately 10% of patients) 5
• Rare pustular psoriasis flare upon withdrawal 5

Never use clobetasol on ulcerated skin, as it will delay healing and increase infection risk. 2, 5