II. Causes: Focal
- Diffuse
- Androgenetic Alopecia
- Male-Patterned Hair Loss (M-patterned hair thinning)
- Female-Patterned Hair Loss (central hair thinning)
- Telogen Effluvium
- Anagen Effluvium
- Systemic conditions (e.g. Hypothyroidism, Iron Deficiency Anemia, nutritional deficiency)
- Alopecia Totalis
- Androgenetic Alopecia
- Focal or patchy - Nonscarring Alopecia (non-cicatrical Alopecia)
- Tinea Capitis
- Trichotillomania
- Traction Alopecia (e.g. tight braiding)
- Alopecia Areata
- Secondary Syphilis (Alopecia syphilitica with moth-eaten appearance)
- Focal or patchy - Scarring Alopecia (Cicatricial Alopecia, uncommon)
- Congenital defects
- Trauma
- Chemical agents (caustic substances)
- Burns
- Radiation
- Inflammatory dermatoses
- Discoid Lupus Erythematosis
- Sarcoidosis
- Lichen Planus follicularis
- Necrobiosis Lipoidica diabeticorum
- Infection
- Neoplasm
III. History
- History of present illness
- Duration of Hair Loss
- Pattern of Hair Loss (see below)
- Progression of Hair Loss
- Family History of Hair Loss
- Hair Loss type
- Broken hairs: Tinea Capitis, Trichotillomania
- Hairs lost by roots
- Concurrent systemic symptoms (e.g. weight loss, Fatigue) or systemic illness or endocrinopathy (e.g. Hypothyroidism)
- Concurrent psychiatric illness or significant stress, pregnancy or febrile illness (with abrupt onset)
- Recent medication changes
- Hyperandrogenism in women
- Excessive hair care product use (straightening agents, Shampoos)
- Nail changes
- Alopecia Areata (esp. Nail Pitting)
IV. Exam: Hair
- Hair distribution and areas of thinning
- Hair Pull Test
- Scalp scarring
- Inflammation
- Scaling
- Loss of Hair Follicles in non-scarring Alopecia
- Hair Shaft exam
- Scalp with Scaling, Pustules, crusts, erosions or erythema or local adenopathy
- Infection
- Dry, broken hair
V. Signs: Patterns of Hair Loss
- M-Pattern in Men (bi-temporal, frontal, vertex) or central and vertex thinning (with spared frontal hair) in women
- Diffuse Hair Loss
- Alopecia Areata (or if involves the entire body, Alopecia Totalis or universalis)
- Telogen Effluvium
- Toxin or Chemotherapy exposure
- Endocrinopathy
- Focal Hair Loss
VI. Labs
- Potassium Hydroxide (KOH) of scalp scraping
- Consider additional labs based on Alopecia type
- Scalp Biopsy Indications (4 mm Punch Biopsy)
- Scarring Alopecia (not diagnostic if Trauma related)
- Unusual Hair Loss pattern
VII. Management
- Refer cicatrical Alopecia (scarring Alopecia)
- See specific Alopecia types for management
VIII. Resources
- National Alopecia Areata Foundation
IX. References
- Nielson (1995) Am Fam Physician 51:1513-28 [PubMed]
- Phillips (2017) Am Fam Physician 96(6): 371-8 [PubMed]
- Price (1999) N Engl J Med 341:964-73 [PubMed]
- Shapiro (2000) Can Fam Physician 46:1469-77 [PubMed]
- Sperling (1998) Med Clin North Am 82:1155-69 [PubMed]
- Springer (2003) Am Fam Physician 68(1):93-102 [PubMed]