How should I evaluate and treat a patient with suspected scarring (cicatricial) alopecia?

Evaluation and Management of Scarring (Cicatricial) Alopecia

For suspected scarring alopecia, perform an early scalp biopsy with multiple stains (H&E, PAS, Weigert) for definitive diagnosis, and initiate aggressive anti-inflammatory treatment immediately to prevent irreversible follicular destruction. 1

Clinical Assessment

Key clinical features to identify:

• Assess for complete absence of follicular ostia (visible pore openings), which is the hallmark clinical sign distinguishing scarring from non-scarring alopecia 2
• Document the time course of hair loss, presence of scalp symptoms (pain, burning, pruritus), signs of inflammation or infection, ease of hair pull-out, and any associated nail changes 1
• Examine the entire body surface, not just the scalp, as systemic conditions like lupus erythematosus can cause scarring alopecia 1
• Look for specific patterns: patchy hair loss with scalp inflammation, erythema, scaling, pustules, or follicular hyperkeratosis 3, 4

Trichoscopy (Dermoscopy)

Trichoscopy is essential as a non-invasive bedside tool that identifies specific patterns distinguishing between different scarring alopecia subtypes, guides optimal biopsy site selection, and provides photographic documentation to monitor treatment response objectively 1

• Perform trichoscopy at every visit with photographic documentation to track disease progression or treatment response 1

Laboratory Workup

Order targeted laboratory tests to exclude secondary causes and assess for systemic involvement:

• TSH to rule out thyroid disease, which can contribute to hair loss 1
• Serum ferritin to assess for iron deficiency (target >60 ng/mL for optimal hair health) 1
• Vitamin D and zinc levels as deficiencies may contribute to hair follicle dysfunction 1
• Fungal culture when tinea capitis (which can cause secondary scarring) is suspected 1
• Serology for lupus erythematosus when discoid lupus or systemic lupus is in the differential diagnosis 1
• Serology for syphilis when secondary syphilis is suspected 1

Histopathologic Diagnosis

Skin biopsy is essential and should be performed early in the disease course before extensive scarring develops 1:

• Obtain a 4mm punch biopsy from an area showing active inflammation (not from completely scarred areas) 1
• Request multiple stains: hematoxylin and eosin (H&E), periodic acid-Schiff (PAS) to identify fungal elements, and Weigert stain to visualize elastic fibers and assess follicular destruction 1
• A systematic histopathologic approach using multiple criteria allows accurate diagnosis in 92.3% of cases, even in late or pauci-inflammatory phases 1

Classification Based on Inflammatory Infiltrate

Primary scarring alopecias are classified by the predominant inflammatory cell type 3, 4, 5:

• Lymphocytic: discoid lupus erythematosus, lichen planopilaris, frontal fibrosing alopecia, central centrifugal alopecia, pseudopelade of Brocq 5
• Neutrophilic: folliculitis decalvans, tufted folliculitis, dissecting cellulitis of the scalp 5
• Mixed: folliculitis keloidalis 5

Treatment Approach

The primary goal is to stop or slow inflammatory waves and prevent further scarring—treatment cannot reverse established scarring 1, 6:

First-Line Anti-Inflammatory Treatment

• Topical corticosteroids class III to IV applied to affected areas can be considered for most primary scarring alopecias 6
• Intralesional triamcinolone acetonide injections into active inflammatory areas can be considered as first-line treatment 6

Systemic Therapy Selection

Choose systemic therapy based on the predominant inflammatory infiltrate identified on biopsy 6:

• For lymphocytic scarring alopecias: immunomodulating or immunosuppressive agents 6
• For neutrophilic scarring alopecias: antimicrobial or antibiotic agents 6

Monitoring and Support

• Assess for signs of disease activity at each visit using clinical examination and trichoscopy with photographic comparison 1
• Monitor for adverse effects of systemic treatments 1
• Provide psychological support and discuss camouflage techniques, as scarring alopecia significantly impacts quality of life and psychological well-being 6

Critical Pitfalls to Avoid

• Delayed diagnosis is common because hair loss can begin subclinically and progress slowly—maintain high clinical suspicion and biopsy early when scarring alopecia is suspected 6
• Do not wait for extensive scarring before initiating treatment—early aggressive intervention is essential to prevent irreversible follicular destruction 1, 4
• Do not expect hair regrowth in already scarred areas—set realistic expectations with patients that treatment aims to preserve remaining follicles, not restore lost hair 6
• Do not rely solely on clinical appearance in subacute, early, or late disease stages—biopsy is necessary when diagnosis is uncertain 6