What is the type of alopecia characterized by hair loss around the hairline?

Hair Loss Around the Hairline: Frontal Fibrosing Alopecia

Frontal fibrosing alopecia (FFA) is the type of alopecia characterized by hair loss around the hairline, particularly affecting the frontal, temporal, or frontotemporal regions, and is often accompanied by eyebrow loss.

Clinical Presentation and Diagnosis

FFA presents with distinctive features that help differentiate it from other types of alopecia:

• Progressive recession of the frontal, temporal, or frontotemporal hairline
• Often accompanied by eyebrow hair loss (a hallmark feature)
• Primarily affects postmenopausal women, but can occur in premenopausal women and occasionally men 1
• Characterized by a scarring, hairless band at the hairline
• May include additional symptoms:
  • Loss of eyelashes
  • Body hair involvement
  • Facial papules
  • Trichodynia (scalp pain)

Dermoscopic Features

Dermoscopy is a critical diagnostic tool for FFA with high diagnostic accuracy 2, revealing:

• Loss of follicular openings (seen in all cases) 3
• Perifollicular erythema (inflammation around hair follicles) 3
• Perifollicular scaling 3
• Absence of yellow dots (which helps differentiate it from alopecia areata) 3

Differential Diagnosis

FFA must be distinguished from other types of alopecia that may affect the hairline:

• Alopecia areata - characterized by smooth, non-inflamed patches with exclamation mark hairs 4
• Trichotillomania - shows incomplete hair loss with broken hairs firmly anchored in the scalp 4
• Tinea capitis - presents with inflammation and scaling 4
• Telogen effluvium - diffuse shedding rather than localized pattern 4
• Androgenetic alopecia - different pattern of hair loss, typically non-scarring 2

Diagnostic Approach

When evaluating a patient with hairline alopecia:

1. Perform a detailed physical examination focusing on:

   • Pattern of hair loss (frontal/temporal recession)
   • Presence of scarring
   • Eyebrow involvement
   • Other body hair loss

2. Consider laboratory testing as indicated:

   • Complete blood count
   • Ferritin levels
   • Thyroid stimulating hormone
   • Vitamin D 25OH levels 2

3. Perform dermoscopy to identify characteristic features of FFA 2, 3

4. Consider a scalp biopsy when diagnosis is uncertain, which typically shows:

   • T lymphocyte infiltration into the infundibulum and isthmus 3
   • Histopathologic features similar to lichen planopilaris 5, 1

Management Considerations

FFA is a progressive disorder that can result in permanent hair loss, making early diagnosis and prompt treatment critical 5. While no standard treatment regimen exists, several approaches may be beneficial:

• Topical and intralesional corticosteroids may help reduce inflammation 2
• Early intervention is essential as FFA can result in permanent scarring alopecia 5
• Regular follow-up is important to assess disease progression and treatment response 2

Important Considerations

• FFA is considered a clinical variant of lichen planopilaris due to shared histopathologic features 5
• The etiology remains unclear, with potential factors including genetic predisposition, hormonal influences, and chemical exposures 1
• The incidence of FFA appears to be increasing worldwide, possibly due to environmental factors and increased awareness 1
• In men, FFA may present atypically, such as with isolated sideburn loss 6

Early recognition and referral to a dermatologist are crucial for proper management of this progressive condition to minimize permanent hair loss and associated psychological impact.