What is the appropriate evaluation and initial management for a 38‑year‑old woman with discrete patches of hair loss?

Evaluation and Management of Patchy Hair Loss in a 38-Year-Old Woman

Initial Clinical Diagnosis

The most likely diagnosis is alopecia areata, which can be confirmed clinically without laboratory testing by identifying round or oval patches of complete hair loss, short broken "exclamation mark" hairs at the margins, slightly reddened skin, and yellow dots on dermoscopy. 1, 2

Key Diagnostic Features to Look For:

• Round or oval patches of complete hair loss on the scalp 2
• Exclamation mark hairs: short broken hairs with tapered ends around expanding patches 1, 2
• Yellow dots visible on dermoscopy (regular round pattern indicates active disease) 1, 2
• Nail involvement in approximately 10% of cases (pitting, ridging) 1, 2
• Slightly reddened but otherwise normal-appearing skin 1

Critical Differential Diagnoses to Exclude:

• Trichotillomania: incomplete hair loss with firmly anchored broken hairs (still in anagen phase, unlike exclamation mark hairs) 1, 2
• Tinea capitis: scalp inflammation with subtle signs; requires fungal culture if suspected 1, 2
• Telogen effluvium: diffuse thinning rather than discrete patches 1, 2
• Systemic lupus erythematosus and secondary syphilis: require serology if clinical features suggest 1, 2

When to Order Laboratory Tests

Laboratory investigations are unnecessary in straightforward cases of alopecia areata with typical clinical features. 2, 3

Reserve Testing For:

• Atypical presentations where diagnosis is uncertain 2, 3
• Fungal culture if tinea capitis suspected 2
• Skin biopsy for early scarring alopecia concerns 1
• Serology for lupus or syphilis if clinical features suggest 2

Avoid ordering extensive autoimmune panels in straightforward cases—this is a common pitfall. 4

Treatment Algorithm

Step 1: Initial Management Decision

For limited patchy alopecia areata of short duration (<1 year), reassurance without active treatment is the evidence-based first-line approach, as spontaneous remission occurs in up to 80% of patients with a small number of circumscribed patches. 1, 3

• Counsel that visible regrowth is unlikely within the first 3 months after a new patch appears 3
• Explain that 34-50% of patients achieve spontaneous remission within one year 1, 4
• Emphasize that hair follicles are preserved and recovery potential is maintained even in longstanding disease 1, 2

Step 2: Active Treatment (If Patient Desires Intervention)

If the patient requests treatment or has cosmetically significant disease, intralesional triamcinolone acetonide injections are the first-line therapy with the strongest evidence (Strength B, Quality III). 2, 3

Intralesional Corticosteroid Protocol:

• Triamcinolone acetonide 5-10 mg/mL or hydrocortisone acetate 25 mg/mL injected just beneath the dermis 3
• Each 0.05-0.1 mL injection produces approximately 0.5 cm diameter tuft of hair growth 3
• Repeat monthly injections until satisfactory response is achieved 2, 3
• 62% full regrowth rate in patients with ≤5 patches each <3 cm in diameter 2, 3
• Beneficial effect typically persists for about 9 months, then maintenance injections often required 3
• Skin atrophy at injection sites is a consistent side effect 4

Alternative: Potent Topical Corticosteroids (Limited Evidence)

Clobetasol propionate 0.05% foam or cream applied twice daily is a second-line option, but evidence quality is limited (Strength C, Quality III). 2, 3

• Achieved ≥50% hair regrowth in only 21% of treated sites versus 3% with placebo at 12 weeks 2, 3
• A separate RCT of 0.25% desoximetasone cream showed no significant benefit over placebo 2, 3
• Folliculitis is the most common side effect 2, 3

Adjunctive Therapy:

• Topical minoxidil 5% can be added to intralesional or topical steroid regimens 2, 3
• Should not be used as monotherapy for alopecia areata 2, 3

Critical Caveats and Pitfalls

No treatment has been shown to alter the long-term course of alopecia areata; all interventions only induce temporary hair growth, with high relapse rates occurring even with initially successful treatment. 3, 4

• All treatments must be continued to maintain effect 3
• Patients should be forewarned about high relapse rates 2
• Alopecia areata has no direct impact on general health that justifies hazardous treatments of unproven efficacy 4

Treatments to Avoid:

• Systemic corticosteroids: unfavorable risk-benefit ratio 4
• PUVA therapy: lack of efficacy 4
• Oral zinc and isoprinosine: ineffective in controlled trials 4

Prognostic Counseling

Disease severity at presentation is the strongest predictor of long-term outcome: 68% of patients with <25% initial scalp hair loss report being disease-free at follow-up, compared to only 8% with >50% initial hair loss. 1, 2

• Almost all patients experience more than one episode of the disease 1
• 14-25% progress to total scalp hair loss (alopecia totalis) or complete body hair loss (alopecia universalis), from which full recovery is unusual (<10%) 1
• Patients with long-standing extensive alopecia have poor prognosis and high failure rates with all treatment modalities 3, 4

Psychosocial Management

Addressing the psychological impact is essential, as patients frequently experience self-consciousness, embarrassment, anger, or feelings of rejection despite the condition having no direct impact on general health. 2, 3, 4

• The psychological burden can be substantial and may require psychological support 2, 4
• For extensive, treatment-refractory disease, wigs are often the most effective means of improving quality of life 3, 4

When to Refer to Dermatology

• Diagnostically challenging cases where the diagnosis remains uncertain 5
• Extensive alopecia (>50% scalp involvement) with poor prognosis 3
• Treatment-refractory disease requiring advanced therapies 5
• Consideration of surgical options (hair transplantation) in carefully selected patients 6