## 2.4 Scarring (Cicatricial) Alopecias Cicatricial alopecias refer to a heterogeneous group of disorders characterized by permanent hair follicle destruction, irreversible hair loss, and replacement by fibrous scar tissue. Early diagnosis and treatment are critical, as follicular damage is irreversible once scarring occurs. Classified broadly into two categories: - **Primary cicatricial alopecia**: Follicle destruction due to direct inflammation. - **Secondary cicatricial alopecia**: Hair follicle loss secondary to external trauma, infections, burns, or neoplasms. This section will focus primarily on **Primary Cicatricial Alopecias**, highlighting two important examples: 1. **Lichen Planopilaris (LPP) including Frontal Fibrosing Alopecia (FFA)** 2. **Discoid Lupus Erythematosus (DLE)** --- ## 1. Lichen Planopilaris (LPP) and Frontal Fibrosing Alopecia (FFA) ### Definition and Pathogenesis: - LPP is a lymphocyte-mediated inflammatory disorder of the hair follicles and a variant of lichen planus affecting scalp hair follicles. - FFA is a specific subtype of LPP predominantly affecting postmenopausal women, characterized by band-like progressive hair loss along the frontotemporal scalp margin and eyebrows. ### Clinical Presentation: **Lichen Planopilaris (classic type):** - Patchy alopecia with perifollicular erythema, hyperkeratosis, scaling, and intense pruritus or burning. - Typically affects vertex or parietal scalp areas first. - Active areas: redness and follicular scaling; Late stages: smooth, atrophic, shiny skin with permanent loss of follicular openings. **Frontal Fibrosing Alopecia (FFA subtype):** - Symmetrical progressive hairline recession involving frontal and temporal scalp margins. - Loss of eyebrow hairs (madarosis) frequently precedes or accompanies scalp hair loss. - Facial papules, hypopigmentation, or erythema along hairline possible. ### Diagnostic Approach: - **Clinical:** Typical distribution (frontotemporal in FFA, patchy/scattered in classic LPP), perifollicular inflammation, and scarring. - **Trichoscopy:** Perifollicular erythema and scales ("peripilar casts"), loss of follicular openings, white fibrotic dots. - **Histology (biopsy, diagnostic gold standard):** Lymphocytic interface dermatitis, perifollicular fibrosis, follicular epithelial destruction, lichenoid infiltrate ("band-like" lymphocytic infiltration). ### Management: - Early initiation critical; goal is to halt inflammatory process and preserve remaining follicles. - **First-line:** Potent topical corticosteroids, intralesional triamcinolone injections. - **Second-line (systemic):** Oral hydroxychloroquine, doxycycline, low-dose oral corticosteroids, 5-alpha reductase inhibitors (dutasteride, finasteride), retinoids (acitretin). - Adjunctive measures: Topical calcineurin inhibitors (tacrolimus), minoxidil (non-scarring areas for stimulation). - Prognosis guarded; treatment aims at halting progression, as follicular loss is irreversible. --- ## 2. Discoid Lupus Erythematosus (DLE)-Related Cicatricial Alopecia ### Definition and Pathogenesis: - DLE is a chronic autoimmune connective tissue disorder predominantly affecting skin and scalp, characterized by immune-mediated damage to hair follicles and surrounding dermal structures. ### Clinical Presentation: - Well-demarcated, erythematous, scaly plaques progressing into atrophic scarring alopecia. - Prominent follicular plugging (hyperkeratotic follicular openings), pigmentary changes (hypopigmentation or hyperpigmentation), telangiectasia. - Lesions predominantly involve scalp, face, ears, and other sun-exposed areas. ### Diagnostic Approach: - **Clinical:** Presence of characteristic lesions on sun-exposed skin, follicular plugging, pigmentary changes, associated systemic lupus erythematosus (SLE) symptoms occasionally. - **Trichoscopy:** Prominent follicular keratotic plugging, perifollicular erythema, white patches indicating fibrosis, absent follicular openings. - **Biopsy (essential for diagnosis):** Interface dermatitis, vacuolar degeneration of basal keratinocytes, thickening of basement membrane, dermal mucin deposition, lymphocytic infiltration surrounding hair follicles. ### Laboratory Tests: - ANA (antinuclear antibodies) and autoimmune panel to screen for associated systemic lupus erythematosus. - Blood tests (CBC, ESR, CRP) to assess systemic inflammation. ### Management: - **Photoprotection:** Critical to prevent exacerbation (sun avoidance, broad-spectrum sunscreen). - **First-line treatment:** Potent topical corticosteroids and intralesional corticosteroids. - **Systemic therapy:** Hydroxychloroquine (first-line systemic agent), oral corticosteroids for acute flares. - **Immunosuppressive therapy:** Methotrexate, azathioprine, mycophenolate mofetil in severe or refractory cases. - Regular monitoring for systemic involvement due to potential association with systemic lupus erythematosus. --- ## General Principles in Management of Cicatricial Alopecias: - **Early diagnosis and prompt initiation of anti-inflammatory/immunomodulatory treatments** is key to limiting irreversible hair follicle destruction. - **Multidisciplinary approach:** Collaboration with dermatologists, rheumatologists, immunologists for comprehensive care. - **Psychosocial support:** Important due to emotional and psychological distress associated with permanent hair loss. - **Surgical hair restoration:** Hair transplantation cautiously considered only after disease stabilization (minimum 1–2 years without active inflammation confirmed clinically and histologically). --- ## Clinical Pearls and Insights: - Cicatricial alopecias frequently mimic other scalp disorders; accurate diagnosis is critical and typically requires biopsy. - Active inflammation (erythema, itching, burning, follicular scales) suggests ongoing disease activity and mandates intensified therapy. - Maintenance treatment (topical anti-inflammatories or immunomodulators) often necessary long-term due to chronic relapsing nature. - Frontal Fibrosing Alopecia incidence appears to be rising globally, possibly linked to environmental triggers; early recognition and aggressive treatment yield best outcomes. --- This structured and comprehensive understanding of scarring (cicatricial) alopecias enables precise clinical recognition, targeted therapeutic interventions, and improved patient outcomes through early intervention and evidence-based management strategies.