Can systemic lupus erythematosus cause ulcerative skin lesions on the face, back, and legs?

Can Lupus Cause Wounds to the Face, Back, and Legs?

Yes, systemic lupus erythematosus (SLE) frequently causes skin lesions on the face, back, and legs, though these are typically inflammatory lesions rather than true "wounds" or ulcers. The face is the most commonly affected site, with the classic malar (butterfly) rash appearing in 80% of SLE patients, while the back and legs can develop various lupus-specific and non-specific skin manifestations 1, 2.

Understanding Lupus Skin Manifestations

Lupus causes three main categories of specific cutaneous lesions:

• Acute cutaneous lupus (ACLE) presents as the characteristic malar rash—erythematous macules with telangiectasia across the cheeks and nose—seen in 51-80% of patients and strongly associated with active systemic disease 1, 2, 3
• Subacute cutaneous lupus (SCLE) appears as psoriasiform or annular lesions, typically on sun-exposed areas including the upper back, shoulders, and extensor arms, occurring in 3-7% of patients 1, 2, 3
• Chronic cutaneous lupus (CCLE), particularly discoid lupus, creates well-demarcated, scaly, erythematous plaques that can appear on the face, scalp, and occasionally the legs in 20-25% of patients 1, 2, 3

Distribution Patterns Across Body Sites

The face is overwhelmingly the primary site of lupus skin involvement:

• Malar rash affects the cheeks and nasal bridge while characteristically sparing the nasolabial folds 2, 3
• Discoid lesions commonly involve the face and scalp, causing scarring alopecia in 15% of patients 2, 3
• Photosensitive dermatitis develops in sun-exposed facial areas in 50-63% of patients 2, 3

The back and trunk can develop:

• Generalized maculopapular rashes in approximately 27% of patients 2
• Subacute cutaneous lupus lesions, particularly on the upper back and shoulders 1, 4
• Photosensitive dermatitis in sun-exposed areas 2, 3

The legs may show:

• Vasculitic lesions (purpura, ulcers, or livedo reticularis) in 11-33% of patients, which can present as true ulcerative wounds 2, 3
• Chronic chilblain lupus affecting the lower extremities in 20% of patients 3
• Discoid lesions, though less common than on the face 4, 5

True Ulcerative Wounds vs. Inflammatory Lesions

Most lupus skin manifestations are inflammatory rather than ulcerative:

• The vast majority of facial and truncal lesions are erythematous, scaly, or edematous plaques—not open wounds 1, 2, 4
• True ulcerative "wounds" occur primarily from cutaneous vasculitis, which affects 11-33% of patients and can appear on the legs 2, 3
• Bullous eruptions occur in only 6-10% of patients and may evolve into erosions 2, 3
• Pyoderma gangrenosum, a rare non-specific manifestation causing ulcerative wounds, occurs in only 1.3% of patients 2

Critical Diagnostic Approach

When evaluating suspected lupus skin lesions:

• Perform skin biopsy from the most active erythematous or scaly portion while the lesion remains clinically visible, as diagnostic yield drops markedly after healing 1
• Document specific morphology and distribution to classify lesions as acute, subacute, or chronic cutaneous lupus 1
• Order comprehensive autoantibody testing (ANA, anti-dsDNA, anti-Ro/SSA, anti-La/SSB) and complement levels (C3, C4) to assess for systemic involvement 1, 6
• Use the Cutaneous Lupus Disease Area and Severity Index (CLASI) to quantify disease activity and damage 1

Essential Management Principles

All lupus patients with skin involvement require:

• Mandatory photoprotection with SPF 60+ sunscreen, sun avoidance, and protective clothing, as UV exposure triggers and worsens lesions 1, 2, 4
• Strong counseling on smoking cessation, as smoking impairs response to antimalarial therapy 1
• Hydroxychloroquine as first-line systemic therapy for cutaneous lupus not controlled with topical corticosteroids 1

Common Pitfalls to Avoid

Do not assume all skin lesions in lupus patients are lupus-related—perform biopsy to exclude infections, drug reactions, or other inflammatory dermatoses, particularly in immunosuppressed patients 1. The presence of skin lesions, especially acute cutaneous lupus, strongly correlates with active systemic disease requiring comprehensive organ assessment 2, 4. Conversely, non-specific lesions like vasculitis or bullae often indicate disease flares requiring treatment escalation 2.