What causes facial alopecia when no medications or vitamins are suspected?

Causes of Facial Alopecia When Medications or Vitamins Are Not Suspected

Facial alopecia is most commonly caused by autoimmune conditions like alopecia areata, which is mediated by T lymphocytes targeting hair follicles and has genetic predispositions with links to other autoimmune diseases. 1, 2

Primary Causes

• Alopecia areata - An autoimmune condition where T lymphocytes target hair follicles, causing patchy, non-scarring hair loss that can affect facial hair 1
• Genetic predisposition - About 20% of people with alopecia areata have a family history, suggesting hereditary factors 1, 2
• Autoimmune associations - Alopecia areata is linked to other autoimmune diseases, supporting an autoimmune pathogenesis 1

Nutritional Factors

• Vitamin D deficiency - Multiple studies have found lower serum vitamin D levels in patients with alopecia areata compared to controls 1, 2
• Zinc deficiency - Serum zinc levels tend to be lower in patients with alopecia areata, potentially contributing to hair loss 2
• Folate deficiency - May contribute to hair loss patterns including facial alopecia 2

Other Important Causes

• Trichotillomania - Compulsive hair pulling that can affect facial hair; often confused with alopecia areata 1
• Tinea barbae - Fungal infection affecting facial hair that can cause patchy hair loss 1
• Frontal fibrosing alopecia - A scarring alopecia that can affect the frontotemporal hairline and eyebrows 3, 4
• Telogen effluvium - Stress-induced hair shedding that can affect all body hair including facial hair 1
• Early scarring alopecia - Various forms of scarring alopecia can affect facial hair 1
• Systemic lupus erythematosus - Can cause hair loss including facial areas 1
• Secondary syphilis - Can present with patchy hair loss including facial areas 1

Diagnostic Approach

• Dermoscopy - Essential tool for diagnosis of alopecia areata, looking for:

  • Yellow dots (regularly round)
  • Exclamation mark hairs (dystrophic hairs with fractured tips)
  • Cadaverized hairs (fractured before emergence from scalp) 1, 2

• Laboratory testing to rule out underlying causes:

  • Serum vitamin D levels
  • Zinc levels
  • Folate levels
  • Iron status (though evidence is conflicting for alopecia areata) 1, 2

• Additional tests when diagnosis is uncertain:

  • Fungal culture (for tinea)
  • Skin biopsy (particularly for scarring alopecias)
  • Serology for lupus erythematosus
  • Serology for syphilis 1

Prognosis Factors

• Severity at presentation - Patients with less severe disease initially (less than 25% hair loss) have better prognosis (68% report being disease-free at follow-up) 1
• Age of onset - Onset during childhood has less favorable prognosis 1
• Pattern of hair loss - Ophiasis pattern (alopecia of the scalp margin) has poorer prognosis 1

Common Pitfalls and Caveats

• Alopecia areata can be confused with trichotillomania, but in trichotillomania, broken hairs remain firmly anchored in the scalp (anagen phase) unlike the exclamation mark hairs in alopecia areata 1
• Diffuse alopecia areata can be difficult to diagnose and may require biopsy 1
• The psychological impact of facial alopecia is significant and should be addressed as part of management 1, 5
• Spontaneous remission occurs in up to 80% of patients with limited patchy hair loss of short duration (< 1 year) 1, 6
• No treatments have been conclusively shown to alter the long-term course of alopecia areata 6