What is the recommended evaluation and treatment plan for an adult with secondary scarring alopecia secondary to a primary scalp disorder such as lichen planopilaris, discoid lupus erythematosus, chronic cutaneous lupus, severe acne, folliculitis decalvans, or a history of burns, radiation, or surgical excision?

Secondary Scarring Alopecia: Evaluation and Treatment

Immediate Diagnostic Priority

For secondary scarring alopecia from lichen planopilaris, discoid lupus, burns, radiation, or surgical excision, perform scalp biopsy when diagnosis is uncertain or to confirm the underlying etiology, as histopathology is the dependable tool for identifying the cause and guiding early treatment 1, 2.

Initial Clinical Evaluation

Key History Elements

• Document the primary disorder: Establish whether the scarring resulted from lichen planopilaris, discoid lupus erythematosus, chronic cutaneous lupus, severe acne, folliculitis decalvans, burns, radiation, or surgical excision 3, 4
• Assess disease activity: Determine if the underlying inflammatory process is active or burned out, as this fundamentally changes management 1, 4
• Identify associated symptoms: Look for scalp tenderness, pruritus, or burning that suggests ongoing inflammation 3

Physical Examination Findings

• Examine for follicular destruction: Secondary scarring alopecia shows permanent replacement of hair follicles with scar tissue 1, 4
• Assess scalp for inflammation: Active disease may show erythema, scaling, or pustules depending on the underlying condition 1
• Evaluate extent and pattern: Document the size, location, and shape of affected areas, as these determine surgical candidacy 5

Diagnostic Workup

Biopsy Indications

• Perform scalp biopsy for uncertain diagnosis: Histopathology identifies the specific underlying cause and inflammatory cell type (lymphocytic, neutrophilic, or mixed) 1, 2
• Biopsy at the active margin: Sample from the edge of expanding lesions where follicular destruction is ongoing 1

Laboratory Testing for Active Disease

• Lupus serology: Order when discoid lupus or chronic cutaneous lupus is suspected, particularly with systemic features 6
• Fungal culture: Obtain if any scaling or inflammation suggests superimposed infection 6
• Consider nutritional assessment: Check vitamin D, zinc, and ferritin if diffuse thinning accompanies the scarring 6, 7

Treatment Algorithm

For Active Inflammatory Disease

The primary goal is disease stabilization to prevent further follicular destruction 3, 1:

First-Line Medical Management

• Intralesional corticosteroids: Use triamcinolone acetonide 5-10 mg/mL for localized active disease 7, 8
• Systemic corticosteroids: Consider oral prednisolone starting at 40 mg daily with 6-week taper for extensive active disease 7
• Immunosuppressive agents: Traditional options include hydroxychloroquine for lupus-related scarring and doxycycline for folliculitis decalvans 3

Emerging Therapies for Refractory Cases

• JAK inhibitors show the most promise: Recent evidence demonstrates potential for disease stabilization through modulation of inflammatory pathways 3
• TNF-α inhibitors: Demonstrate benefit in severe, treatment-resistant scarring alopecias 3
• IL-17 inhibitors: Show potential for disease resolution in select cases 3

Critical caveat: These biologics and JAK inhibitors are off-label for scarring alopecia, but represent the most promising options when conventional therapy fails 3.

For Stable, Burned-Out Disease

Once inflammation has resolved and no further follicular destruction is occurring, surgical options become appropriate 5, 4:

Surgical Decision Algorithm Based on Lesion Characteristics

Size considerations 5:

• Small defects (<3 cm): Total excision with direct closure in 10 cases showed good results
• Medium defects (3-6 cm): Scalp reduction through serial excision over multiple stages
• Large defects (>6 cm): Tissue expansion followed by advancement flaps

Location considerations 5:

• Scalp vertex/crown: Tissue expanders with advancement flaps provide best cosmetic outcome
• Frontal hairline: Strip composite hair-bearing scalp grafts maintain natural hair direction
• Eyebrow: Composite hair-bearing grafts from scalp donor sites

Shape considerations 5:

• Linear scars: Direct excision with layered closure
• Irregular patches: May require combination of excision and grafting

Surgical Timing

• Confirm disease quiescence: Ensure at least 12-18 months of stability before surgical intervention 4
• Hair transplantation: Reserved for localized stable scars without active inflammation 4

Common Pitfalls to Avoid

• Attempting surgery during active inflammation: This leads to graft failure and extension of scarring 1, 4
• Delaying aggressive treatment in active disease: Early intervention prevents irreversible follicular destruction 1
• Overlooking psychological impact: Scarring alopecia causes devastating effects on quality of life requiring psychological support 7
• Misclassifying as primary scarring alopecia: Secondary scarring has different prognosis and treatment than primary cicatricial alopecias 2, 4

Prognosis and Counseling

• Permanent hair loss: Hair follicles destroyed by scar tissue cannot regenerate 1, 4
• Treatment goals differ by disease stage: Active disease requires stabilization; stable disease may benefit from reconstruction 3, 4
• Surgical success rates: Good results achieved in 75% (18/24) of cases when appropriate technique matched to defect characteristics 5