What is the initial workup for hair loss?

Initial Workup for Hair Loss

The initial workup for hair loss should include a detailed clinical assessment, physical examination, and targeted laboratory testing to determine the specific cause before initiating treatment. 1

Clinical Assessment

• Obtain detailed history about onset, duration, and progression of hair loss 1
• Document family history of hair loss, which is present in approximately 20% of alopecia areata cases 1
• Review medication use that could cause anagen effluvium (chemotherapy, anticoagulants, retinoids, antithyroid drugs) 1, 2
• Inquire about hair care practices that might cause traction alopecia (tight braids, ponytails, extensions) 1
• Ask about systemic symptoms that might suggest autoimmune disease or other underlying conditions 1, 3
• Assess psychological impact, as hair loss can cause significant distress 4

Physical Examination

• Examine the scalp for redness, inflammation, or scaling which may suggest conditions like tinea capitis 1
• Look for characteristic patterns of hair loss:
  • Patchy loss with "exclamation mark hairs" suggests alopecia areata 1
  • Diffuse thinning with preserved frontal hairline in women or bitemporal recession and vertex balding in men suggests androgenetic alopecia 2
  • Broken hairs with irregular length may indicate trichotillomania 1
• Examine nails, which are involved in about 10% of alopecia areata patients 1
• Check for lymphadenopathy, particularly occipital and cervical nodes 1
• Perform hair pull test: gently pulling 50-60 hairs between thumb and forefinger; extraction of more than 10% indicates active hair shedding 5

Laboratory Testing

• For all patients with hair loss, order complete blood count, ferritin, thyroid stimulating hormone, and vitamin D levels 5
• Additional testing based on clinical suspicion:
  • Antinuclear antibody test if autoimmune disease is suspected 3
  • Testosterone, DHEAS, and androgen panel for women with signs of hyperandrogenism 2
  • Fungal culture or KOH preparation if tinea capitis is suspected 1

Specialized Diagnostic Techniques

• Dermoscopy can confirm diagnosis by showing characteristic patterns:
  • Yellow dots, exclamation mark hairs in alopecia areata 1
  • Peripilar brown halo in androgenetic alopecia 2
  • Black dots and broken hairs in trichotillomania 1
• Scalp biopsy is essential in all cases of scarring alopecia and when diagnosis remains unclear after initial evaluation 5
• Hair pluck test can help differentiate between anagen and telogen effluvium 6

Common Pitfalls to Avoid

• Misdiagnosing diffuse alopecia areata as telogen effluvium 1
• Overlooking tinea capitis, especially with subtle inflammation 1
• Failing to recognize trichotillomania, characterized by broken hairs remaining firmly anchored 1
• Ordering unnecessary laboratory testing for typical presentations of pattern hair loss 1
• Neglecting the psychological impact of hair loss, which can lead to anxiety and depression 2

Prognostic Considerations

• Patients with less than 25% hair loss initially have better outcomes, with 68% disease-free at follow-up 1
• Patients with more than 50% hair loss initially have poorer outcomes, with only 8% disease-free at follow-up 1
• Early intervention generally leads to better treatment response, particularly in androgenetic alopecia 2