Alopecia Areata (AA) 

Alopecia areata is a common non-scarring autoimmune hair loss disorder targeting hair follicles, resulting in sudden, smooth, localized patches of hair loss on the scalp or any hair-bearing site. Its course is relapsing and unpredictable.

1. Pattern and Timeline:

• Onset: Sudden, over weeks, resulting in well-defined, smooth patches on the scalp. May involve the beard, eyebrows, or body hair.

• Patterns: Most common is patchy. Less common but important patterns:

  • • Alopecia Totalis: Loss of all scalp hair.

    • Alopecia Universalis: Loss of all body hair.

    • Ophiasis: Band-like loss along the occipital/temporal margins (poor prognosis).

• Course: Many patients with patchy AA experience spontaneous regrowth within 12 months, but relapses are common.

2. Symptoms and Associated Features:

• Sensation: Usually asymptomatic; some report mild tingling or tightness (trichodynia) in active patches.

• Nails: Patients may notice fine pitting, ridging, or trachyonychia (rough sandpaper nails), which is a sign of more severe disease and a poor prognostic indicator.

• Autoimmune History: Patients should be asked about personal or family history of Thyroid disease, Vitiligo, Atopic Dermatitis, or Lupus.

Crucial Note for Darker Skin Tones:

• Differential Diagnosis: The disease pattern is the same, but you must rule out Traction Alopecia and Central Centrifugal Cicatricial Alopecia (CCCA), which are particularly common in people of African descent.

• Psychosocial Impact: The emotional and psychological burden (anxiety, depression, social avoidance) is often greater where hair is culturally central to identity.

1. Scalp / Hair Examination:

• Patches: Non-scarring, well-demarcated patches of hair loss. The skin within the patch is smooth and normal (not shiny or atrophic). Follicular openings are visible.

• Pathognomonic Sign: Exclamation-mark hairs at the patch margins (hairs tapered proximally, thicker distally).

• Hair Pull Test: A positive test (pulling >10% of grasped hairs away) at the margin indicates active disease.

2. Key Findings in Darker Skin Tones:

• Regrowing Hair: Regrowing hairs may be hypopigmented or white, creating a high contrast against the surrounding pigmented skin.

• Pigment Change: Look for hypopigmented streaks or patches left by prior intralesional steroid injections.

3. Excluding Scarring Alopecias (Essential in Darker Skin):

• The absence of follicular openings or the presence of perifollicular scale, erythema, or hyperpigmentation suggests a scarring alopecia (like CCCA or Discoid Lupus) rather than AA.

• Look closely for the central, circular spreading pattern typical of CCCA (usually on the crown/vertex) or the distinct hairline loss of Traction Alopecia.

Management involves controlling disease activity, minimizing treatment side effects, and providing crucial psychological support.

1. General Principles:

• Prognosis: Counsel patients about the unpredictable course. Prognosis is worse with childhood onset, ophiasis pattern, or coexistent nail dystrophy.

• Psychosocial Care: Screen for anxiety/depression. Provide camouflage options (wigs, hair fibres) and signpost to support organizations.

2. Mild to Moderate Disease (<50% Scalp):

• First-line: Intralesional Corticosteroids (ILCS): Triamcinolone acetonide (2.5–10 mg/mL) injected into the dermis every 4–6 weeks. This has a high success rate (60–67% regrowth).

• Adjunctive: Topical Minoxidil (5%) or potent topical steroids (e.g., Clobetasol) for needle-averse patients.

3. Severe or Extensive Disease ( >50% Scalp, Totalis, Universalis):

• Referral: These cases require specialist care.

• Oral JAK Inhibitors: Medications like Baricitinib are now approved for severe AA, showing significant regrowth but require long-term monitoring for serious side effects (e.g., infections, VTE).

• Topical Immunotherapy (Sensitization): Use of DPCP or SADBE to induce an allergic contact dermatitis.

Darker Skin Tones – Specific Treatment Risks:

• ILCS Technique: Use the lowest effective concentration and ensure shallow injections to reduce the risk of local atrophy and hypopigmentation, which is highly visible and distressing.

• Immunotherapy: Topical immunotherapy can cause hypo- and hyperpigmentation that must be carefully discussed, as the color change can be highly visible.

• Hair Practices: Advise low-tension styles and cautious use of chemical relaxers to prevent traction damage that can mimic or worsen AA.

DermNet NZ – Alopecia Areata: https://dermnetnz.org/topics/alopecia-areata

StatPearls / NCBI Bookshelf – Alopecia Areata (2024 update): https://www.ncbi.nlm.nihim.gov/books/NBK537000/

The Pharmaceutical Journal – Common dermatological conditions in skin of colour (Belmo et al., 2021): https://pharmaceutical-journal.com/article/ld/common-dermatological-conditions-in-skin-of-colour

Skinsight – Alopecia Areata: https://skinsight.com/skin-conditions/alopecia-areata/