What is the treatment for a scaly rash over bilateral palms and soles with a papular rash over the neck and face?

Treatment for Scaly Rash on Palms/Soles with Papular Rash on Neck/Face

This presentation requires immediate consideration of secondary syphilis, which must be ruled out before initiating treatment, as a palmoplantar rash with facial/neck involvement is a classic presentation of this treatable infection that can cause severe morbidity if missed. 1, 2

Critical First Step: Rule Out Life-Threatening and Infectious Causes

Before initiating any treatment, you must obtain:

• VDRL/RPR testing - Secondary syphilis classically presents with scaly palmoplantar lesions plus papular rash on face/neck 2
• Complete blood count - To evaluate for Rocky Mountain Spotted Fever (RMSF), which presents with rash on palms/soles spreading to face/neck, with thrombocytopenia being a key finding 1
• Tick exposure history - RMSF has 5-10% mortality if untreated and requires immediate doxycycline 1
• Bacterial/viral/fungal cultures if any signs of superinfection are present 1

Differential Diagnosis Based on Distribution Pattern

The combination of palmoplantar AND facial/neck involvement narrows the differential significantly:

Infectious causes to exclude:

• Secondary syphilis (Treponema pallidum) - papulosquamous rash on palms/soles with facial involvement 2
• RMSF - maculopapular rash starting on wrists/ankles spreading to palms/soles and trunk, can involve face 1
• Hand, foot, and mouth disease (in toddlers) - vesicular lesions on palms/soles with oral involvement 2
• Meningococcal infection - can present with palmoplantar rash 2

Non-infectious causes:

• Psoriasis vulgaris - can involve palms, soles, and face simultaneously 1
• Drug-induced hypersensitivity reaction - palmoplantar involvement with facial rash 2
• Papulopustular exanthema from EGFR inhibitors/MEK inhibitors (if on cancer therapy) - papules on face/neck with palmoplantar involvement 1

Treatment Algorithm Once Infectious Causes Excluded

If Psoriasis is Confirmed:

For palmoplantar psoriasis with facial involvement, systemic therapy is justified regardless of body surface area involved, as quality of life impact is disproportionate to BSA. 1

First-line systemic treatment:

• Acitretin 25 mg daily - Palmoplantar psoriasis is particularly responsive to oral retinoids, with substantial improvement typically seen within 2 months 1
• Monitor lipids (manage elevated triglycerides with fibrates, elevated cholesterol with statins) 1
• Dose can be reduced to 25 mg on alternate days once controlled 1

Topical adjunctive therapy:

• Clobetasol propionate solution for scalp/face (if facial lesions present) - applied twice daily 1, 3
• High-potency topical corticosteroids under occlusion for palms/soles 1
• Limit clobetasol use to 2-week treatment periods to avoid HPA axis suppression 3

Alternative systemic options if acitretin fails:

• Methotrexate or cyclosporine (monitor for hepatotoxicity/nephrotoxicity respectively) 1
• Biologics (adalimumab, infliximab, ustekinumab) for refractory cases 1, 4

Phototherapy options:

• Soak PUVA (palms/soles soaked in methoxsalen solution for 15-30 minutes before UVA) - 2-3 times weekly for several months 1
• Consider combining acitretin with PUVA to reduce treatment number and skin cancer risk 1

If Drug-Induced (Oncology Patient on EGFR/MEK Inhibitors):

For Grade 1-2 papulopustular rash (10-30% BSA):

• Continue causative drug at current dose 1
• Oral doxycycline 100 mg twice daily OR minocycline 50 mg twice daily for 6 weeks 1
• Topical low/moderate potency steroid to face and affected areas twice daily 1
• Reassess after 2 weeks 1

For Grade ≥3 or intolerable Grade 2:

• Interrupt causative drug until Grade 0-1 1
• Continue oral antibiotics as above 1
• Add systemic corticosteroids (prednisone 0.5-1 mg/kg for 7 days) 1
• Consider isotretinoin 20-30 mg/day (consult dermatology first) 1

If Pompholyx/Vesicular Palmoplantar Dermatitis:

• Topical high-potency corticosteroids as cornerstone therapy 5
• Topical calcineurin inhibitors as alternative 5
• Topical PUVA with methoxsalen for refractory cases 5
• Systemic corticosteroids for bullous presentations 5

Critical Pitfalls to Avoid

• Never start treatment without ruling out secondary syphilis - this is a treatable infection with severe consequences if missed 2
• Do not delay doxycycline if RMSF is suspected - mortality is 5-10% and increases with delayed treatment; do not wait for rash to involve palms/soles as this indicates advanced disease 1
• Avoid systemic corticosteroids as monotherapy in psoriasis - can cause disease flare during taper 4
• Do not use clobetasol on face for >2 weeks - high risk of skin atrophy in facial areas 3
• Monitor for HPA axis suppression with potent topical steroids on large surface areas 3
• Obtain pregnancy test before starting acitretin - highly teratogenic 3