Resident Editor: Juliana Macri, M.D.
Faculty Editor: Ryan Arakaki, M.D.
BOTTOM LINE ✔ Assess hair loss pattern and acuity, as well as associated triggers to determine etiology ✔ Non-scarring alopecia can be treated in primary care ✔ Refer scarring or refractory alopecia |
Background
- Alopecia describes baldness. Effluvium or defluvium describes the shedding of hair
- Hair grows in three phases: Anagen (active growing), catagen (degeneration), and telogen (resting)
- Hair loss can be non-scarring (aka. non-cicatricial), which is reversible, versus scarring (aka. cicatricial), which is permanent and requires a dermatologic referral
- Alopecia is not inherently dangerous but can cause social and psychological distress, and affect the quality of life.
Differential
- Scarring alopecia (rare): Primary or secondary. Includes autoimmune causes (e.g. discoid lupus)
- Focal/patchy: Alopecia areata, tinea capitis, trichotillomania
- Diffuse: Telogen or anagen effluvium, androgenic alopecia, systemic disease (e.g. hypothyroidism, iron or other nutritional deficiency), alopecia totalis (if involvement beyond scalp)
Evaluation
History
- The onset of hair loss: Abrupt suggestive of anagen or telogen effluvium; gradual onset suggestive of alopecia areata, androgenetic alopecia, or scarring alopecias
- Pattern of hair loss: patchy vs. diffuse, male or female pattern
- Associated conditions/triggers
- Hair product use and tight hairstyles
- Medications: chemotherapy, retinoids, anticoagulants, anticonvulsants, beta-blockers, thyroid medications, OCP discontinuation (drug-induced alopecia manifests as telogen or anagen effluvium)
- Recent physical or emotional stressors, in the past 2-5 months (can cause telogen effluvium)
- History of anxiety or psychiatric disease (consider trichotillomania)
- Systemic symptoms (e.g. hypothyroidism, recent health concerns), other skin conditions
- Family history
Physical Exam
- Evidence of tissue destruction (inflammation, atrophy, scarring), particularly absence of follicular orifices à dermatology referral
- Pattern:
- Male pattern: Varies between thinning bi-temporally, to loss at frontal and vertex hairline to complete loss except for the preservation of hair at the occiput and temporal fringes
- Female pattern: diffuse thinning at the vertex with sparing of frontal hairline, does not result in complete baldness (as compared to men)
- Hair quality: assess for dry, broken, or thin hair
- Evidence of infection: Scaling, pustules, crusts, erosions, erythema, adenopathy
- Pull test: Grasp 40-60 hairs at their base, and apply gentle traction. Positive if > 10% of hairs are pulled, suggestive of active hair loss (e.g. telogen or anagen effluvium, or alopecia areata). Not fully sensitive, and difficult to standardize.
Testing
- No routine testing
- Depending on the history and physical exam, consider CBC, TSH, ALT, Cr, iron studies, testing for copper or zinc deficiency, vitamin D
- If concern for virilization and male pattern hair loss in women, consider free and total testosterone, DHEAS, and prolactin
- Fungal culture if itching, scaling, pustules, lymphadenopathy
- Can consider referral for a scalp biopsy, trichogram
Diagnosis and Treatment of Common Causes
- Scarring alopecia should be referred to dermatology
- Non-scarring alopecias can be treated in primary care (see Table 1)
- Consider the psychological impact of hair loss and offer support (online support groups, etc).
- Some patients may consider a wig, hairpiece, tattoos, or makeup to obscure hair loss.
Table 1: Common Non-Scarring Alopecias
Condition |
Notable Features |
Treatment |
Alopecia areata (etiology unknown, possibly autoimmune) |
Acute, patchy hair loss (but can become confluent or generalized); exam with short, thin, and broken hairs, yellow or black dots; “exclamation mark” hair. Can cause hair loss anywhere, not just scalp. |
Often self-limited. Consider intralesional triamcinolone every 4-6 weeks for up to 6 months |
Anagen effluvium |
Acute onset, diffuse hair loss days-weeks after triggering event that interrupts mitosis of the hair follicle (e.g. chemotherapy) |
Limited options – provide psychosocial support. Regrowth expected 1-3 months after offending agent stopped. Minoxidil may help during regrowth.
|
Androgenic alopecia – aka. Male- or female- pattern hair loss (the most common cause of hair loss in men and women)
|
Gradual and progressive onset. + family history. Residual hair becomes finer, vellus. Male or female pattern (see physical exam). Consider thyroid disease, IDA, nutritional deficiency, endocrine disease (see virilization in females) |
Treatment is better at preventing progression than stimulating hair regrowth.
Topical minoxidil (2% or 5%); vertex > frontal response, takes 6-12 months; indefinite treatment recommended. Best evidence. Side effects of contact/irritant dermatitis. Increased shedding in the first 2 months of treatment.
Finasteride 1 mg daily: second line, approved in men. Side effects of decreased libido, ED, gynecomastia. Maybe long-lasting even after d/c of med. Not as effective for women. |
Telogen effluvium |
Acute onset, diffuse, uniform loss; report clumps of hair loss with brushing or in the shower; triggered by a physical or emotional stressor, 3-5 months prior. May see associated nail findings (Transverse or Beau Lines) |
Self-limited (2-6 months) Offer reassurance and treat underlying stressor |
Tinea capitis (most commonly Trichophyton tonsurans; less likely Microsporum audouinii) |
Patchy pattern. May have associated scaling, pruritis, erythema, lymphadenopathy. Caused by dermatophyte infection – often household or fomite exposure (e.g. brushes, hats). Consider skin scraping of the active border with KOH exam |
Systemic treatment (topicals will not penetrate) Oral terbinafine, itraconazole, fluconazole or griseofulvin; examine and treat close contacts
|
Trichorrhexis nodosa |
Dry, broken hair. Can have a genetic component, but frequently caused by trauma (e.g. tight hairstyling, excessive brushing, heat, or harsh chemical products) |
Adjustment of hairstyling routines |
Trichotillomania
|
Uneven, patchy pattern, especially frontoparietal, with twisted or broken off hair. May involve eyelashes and eyebrows. Caused by pulling, twisting, or twirling of hair; associated with anxiety and impulse-control issues
|
Combination of CBT and medications more effective than medications alone; consider psych referral |
References
Phillips TG, Slomiany WP, and Allison R. Hair Loss: Common Causes and Treatment. Am Fam Physician. 2017; 96(6): 371-378.
Wolff K et. Al. Fitzpatrick’s Color Atlas and Synopsis of Clinical Dermatology. 8th Edition, 2017.