What is the initial workup for hair loss?

Initial Workup for Hair Loss

The initial workup for hair loss should include a thorough clinical examination to identify the pattern of hair loss, presence of scalp inflammation, and characteristic features such as exclamation mark hairs, followed by targeted investigations based on the suspected diagnosis. 1

Clinical Assessment

History

• Obtain details about onset, duration, and progression of hair loss 1
• Inquire about family history of hair loss (present in about 20% of alopecia areata cases) 1
• Review medication use that could cause anagen effluvium 1
• Ask about hair care practices that might cause traction alopecia 1
• Document any systemic symptoms that might suggest autoimmune disease 1

Physical Examination

• Determine pattern of hair loss: patchy, diffuse, or patterned 2
• Examine the scalp for:
  • Redness or inflammation 1
  • Scaling (may suggest tinea capitis) 1
  • Presence of short broken hairs (exclamation mark hairs) which suggest alopecia areata 1
• Assess hair shafts for structural abnormalities 1
• Examine nails (involved in about 10% of alopecia areata patients) 1
• Check for lymphadenopathy, particularly occipital and cervical nodes 1
• Use dermoscopy if available to identify specific features:
  • Yellow dots in alopecia areata 1
  • Broken hairs with fractured tips (exclamation mark hairs) 1
  • Cadaverized hairs (fractured before emergence from scalp) 1

Diagnostic Approach

For Suspected Alopecia Areata

• Clinical diagnosis is usually sufficient based on characteristic patchy hair loss with exclamation mark hairs 1
• Dermoscopy can confirm diagnosis by showing yellow dots, exclamation mark hairs, and cadaverized hairs 1
• No routine investigations are required for typical presentations 1

For Uncertain Diagnosis

• Consider the following differential diagnoses:
  • Trichotillomania - look for incomplete hair loss with firmly anchored broken hairs 1
  • Tinea capitis - check for subtle inflammation and scaling 1
  • Early scarring alopecia - look for loss of follicular openings 1
  • Telogen effluvium - diffuse shedding often following a triggering event 1
  • Anagen effluvium - drug-induced diffuse hair loss 1
  • Systemic lupus erythematosus - check for other cutaneous signs 1
  • Secondary syphilis - consider serology if risk factors present 1

Investigations (when diagnosis is uncertain)

• Fungal culture if tinea capitis is suspected 1
• Skin biopsy if scarring alopecia is suspected or diagnosis remains unclear 1
• Serology for lupus erythematosus if systemic symptoms are present 1
• Serology for syphilis if clinically indicated 1

Important Considerations

• Routine screening for autoimmune diseases is not justified despite the association with alopecia areata 1
• Biopsy is rarely needed in children with hair loss conditions but may be necessary in adults with atypical presentations 3
• The prognosis varies significantly based on the extent of hair loss at presentation:
  • Patients with less than 25% hair loss initially have better outcomes (68% disease-free at follow-up) 1
  • Patients with more than 50% hair loss initially have poorer outcomes (only 8% disease-free at follow-up) 1
• Hair loss can cause significant psychological distress and impact quality of life, so addressing these concerns is an important part of management 2

Common Pitfalls to Avoid

• Misdiagnosing diffuse alopecia areata as telogen effluvium - look carefully for exclamation mark hairs 1
• Overlooking tinea capitis - the inflammation may be subtle 1
• Failing to recognize trichotillomania - broken hairs remain firmly anchored unlike in alopecia areata 1
• Unnecessary laboratory testing for typical presentations of alopecia areata 1
• Neglecting the psychological impact of hair loss on patients 2