What is the likely diagnosis and treatment plan for a patient with a bilateral, non-pruritic red rash in front of the ears that improves with Zoryve (cyclosporine) and worsens with sun exposure, with a planned punch biopsy to rule out Lupus?

Likely Diagnosis: Cutaneous Lupus Erythematosus (Subacute or Chronic CLE)

The bilateral, non-pruritic red rash in front of the ears that improves with Zoryve (roflumilast cream) and worsens with sun exposure is most consistent with cutaneous lupus erythematosus, likely subacute cutaneous lupus erythematosus (SCLE) or chronic cutaneous lupus erythematosus (CCLE). The photosensitivity, location, and response pattern strongly suggest lupus-specific skin disease rather than seborrheic dermatitis or other inflammatory conditions 1.

Key Diagnostic Features Supporting CLE

• Photosensitivity is a hallmark feature of cutaneous lupus, with UV light exposure exacerbating all types of CLE 2, 1
• Preauricular location is consistent with sun-exposed areas where CLE commonly manifests 2, 3
• Absence of pruritus is typical for lupus-specific lesions, which more commonly present with stinging or burning sensations rather than itching 2
• Absence of hair loss within the rash helps distinguish this from discoid lupus erythematosus (DLE), which typically causes scarring alopecia in affected areas 4

Essential Diagnostic Workup

The punch biopsy is absolutely necessary and correctly planned 1, 5. The dermatologist should:

• Perform histological analysis looking for interface dermatitis, vacuolar degeneration of the basal layer, lymphocytic infiltrate, and melanophages 6, 1
• Consider direct immunofluorescence on the biopsy specimen to detect immunoglobulin and complement deposition at the dermoepidermal junction 4

Comprehensive autoantibody panel must be ordered 1, 7:

• ANA (antinuclear antibody)
• Anti-dsDNA
• Anti-Ro/SSA and anti-La/SSB (particularly important as SCLE is highly associated with anti-Ro/SSA positivity) 1, 8, 6
• Anti-RNP and anti-Sm
• Anti-phospholipid antibodies
• Complement levels (C3 and C4)

Critical caveat: ANA and anti-dsDNA can be negative in isolated cutaneous lupus, particularly in cases presenting with periorbital or facial erythema 6. Do not rule out CLE based on negative ANA alone 1, 7.

Additional baseline laboratory tests required 1, 7:

• Complete blood count (to assess for cytopenias)
• ESR and CRP
• Serum creatinine and albumin
• Urinalysis with urine protein/creatinine ratio (to screen for renal involvement)

Excluding Systemic Lupus Erythematosus

Screen for systemic involvement through focused history 7, 8:

• Neuropsychiatric symptoms: seizures, headaches, cognitive impairment, depression, paresthesias, numbness, weakness 7
• Joint pain or swelling
• Chest pain or shortness of breath
• Raynaud's phenomenon

If urinalysis is abnormal or creatinine elevated, obtain urine microscopy, consider renal ultrasound, and refer for potential kidney biopsy 1, 7.

Treatment Plan

Immediate photoprotection is mandatory 1, 8, 2:

• SPF 60 or higher sunscreen containing zinc oxide or titanium dioxide 2
• Physical barrier clothing including wide-brimmed hats
• Strict avoidance of sun exposure between 10 AM and 4 PM 1
• Smoking cessation if applicable 2

Continue Zoryve (roflumilast cream) as it is providing benefit, though this is not standard first-line therapy for CLE. The anti-inflammatory properties of this PDE4 inhibitor may be providing symptomatic relief 1.

Add or transition to standard CLE therapy 1, 8, 2:

First-line topical therapy:

• High-potency topical corticosteroids (e.g., clobetasol propionate 0.05% cream) applied twice daily to affected areas 8, 9
• Topical calcineurin inhibitors (tacrolimus 0.1% ointment) can be used as steroid-sparing agents, particularly for facial involvement 8, 9

First-line systemic therapy if topical treatment insufficient:

• Hydroxychloroquine 200-400 mg daily (typically 5 mg/kg/day, not exceeding 400 mg/day) is the cornerstone of CLE treatment 8, 2, 9
• Requires baseline ophthalmologic examination and annual screening for retinal toxicity 8

Second-line systemic options for refractory disease 8, 2, 9:

• Methotrexate 10-25 mg weekly
• Mycophenolate mofetil 1-3 g daily
• Azathioprine 1-3 mg/kg/day

Third-line options for severe refractory cases 8, 2:

• Belimumab (biologic therapy)
• Rituximab
• Anifrolumab

Monitoring Strategy

Use the Cutaneous Lupus Disease Area and Severity Index (CLASI) at each visit to objectively track disease activity and damage 1, 8.

For patients with confirmed CLE, monitor every 6-12 months 1, 7:

• CBC, ESR, CRP
• Serum creatinine and albumin
• Urinalysis
• Anti-dsDNA, C3, and C4 levels (to detect evolution to systemic disease)

Re-evaluate anti-Ro/SSA and anti-La/SSB before any future pregnancy due to risk of neonatal lupus and congenital heart block 1, 7.

Critical Pitfalls to Avoid

• Do not delay biopsy if clinical diagnosis is uncertain or treatment fails 5, 1
• Do not rely solely on ANA testing as it can be negative in isolated cutaneous lupus 1, 7, 6
• Do not prescribe mycophenolate mofetil, cyclophosphamide, or methotrexate if pregnancy is possible without adequate contraception 1
• Do not assume absence of systemic disease based on initial presentation—regular monitoring is essential as CLE can evolve to SLE 1, 2