Alopecia

Alopecia (from Greek “alopekia” a disease like fox mange; “alopex” fox) represents a significant loss or absence of hair, affecting the scalp or any other hair-bearing part of the body. Human hair follicles have three distinct growth phases: anagen (active), catagen (regressive), and telogen (resting). The human scalp contains approximately 100,000 hairs, with an average growth rate of 2.5 mm/week. In healthy individuals, about 50–100 hairs are lost daily, and 25% must be shed before thinning becomes apparent.

Differential Diagnosis

Non-scarring alopecia

• Inflammatory/infectious disorders: Tinea capitis (Trichophyton tonsurans, Microsporum canis), kerion

• Alopecia areata
  –Sudden localized loss of hair in round/oval patches; associated with Scotch plaid nails (transverse and longitudinal pitting rows) in 10–20% of the cases, and with autoimmune disorders
  –Ophiasis alopecia starts the posterior occiput; extends anteriorly, bilaterally
  –Other forms show loss of all scalp hair (alopecia totalis) or body hair (alopecia universalis)

• Trauma: Traction (trichotillomania, tight braiding, ponytails), pressure (prolonged bed rest, especially in infants [occiput])
• Telogen effluvium: Partial alopecia noted 3 months after a stressful event; reversible; rarely involves more than 50% of the hair
• Anagen effluvium: Sudden loss of the growing hairs (80% of the scalp), resulting from the interruption of the anagen phase of the hair cycle; follows chemotherapy (folic acid and purine antagonists, alkylating agents, alkaloids), irradiation, or intoxication (lead, thallium, arsenic, bismuth, coumadin)
• Hair shaft anomalies (moniletrix, trichothiodystrophy, pili torti)
• Seborrheic dermatitis
• Thyroid disease
• Male-pattern alopecia (in both sexes)
• Congenital triangular alopecia
  Scarring alopecia (cicatricial)
• Dermatologic disorders and syndromes: Lichen planus, SLE, acrodermatitis enteropathica, sarcoidosis, scleroderma (localized/systemic), keratosis pilaris, folliculitis decalvans
• Infectious (prolonged scalp infections, tuberculosis, syphilis, herpes zoster)
• Physical trauma (chronic irradiation, trichotillomania, thermic/caustic burns)
• Developmental defects (aplasia cutis) and genetic syndromes (Hallerman-Streiff, Treacher Collins, Marie-Unna hypotrichosis, trisomy 13, etc.)

Workup and Diagnosis

• History
  –Duration, drugs used
  –Stressful events (febrile illness, surgery, shock, diet, injury, emotional stress) preceding the alopecia by 2–4 months
  –Family history for inherited forms; family members or close contacts with scalp infections

• Physical exam
  –Examination of hair root and shaft: “Exclamation point hairs” (hair shaft narrows just near the follicle) are pathognomonic for alopecia areata; telogen hairs have a club-shaped tip; hair is broken in various lengths in trichotillomania or child abuse
  –Examination of the scalp skin: Inflammation, atrophy, scales; “salt-and-pepper” appearance in tinea capitis; Wood lamp examination detects Microsporum,but misses Trichophyton

• Labs
  –Microscopic examination of the hairs with KOH for hyphae
  –Dermatophyte test medium innoculation
  –Fungal cultures from skin scrapings, brushings, hairs
  –Thyroid function tests, especially in patients with alopecia areata (25% have thyroid abnormalities)

• Scalp biopsy to determine cause of scarring alopecia
• Consider presence of trichobezoars and obsessivecomplusive disorders in trichotillomania

Treatment

• Elimination of the precipitating factor/agent
• Tinea capitis: Oral griseofulvin for 4–6 weeks; oral itraconazole, terbinafine, or fluconazole can also be used; selenium sulfide shampoo decreases fungal shedding and hastens healing of lesions
• Alopecia areata: Topical steroids, PUVA, intradermal corticosteroid injections, very rarely systemic steroids
• Kerion is treated with griseofulvin and sometimes with corticosteroids; antimicrobials are not necessary unless secondary infection is suspected
• Use of cooling or a scalp tourniquet during the IV use of certain chemostatic agents (e.g., vincristine)
• Male pattern alopecia: Topical minoxidil, plastic surgery techniques, implantation of nylon filaments
• Psychological assistance; psychiatric evaluation should be considered in trichotillomania and in certain cases antidepressant treatment (fluoxetine, clomipramine)

Book Source Details

• Book Title: In A Page: Pediatric Signs and Symptoms
• Author(s): Jonathan E. Teitelbaum, Kathleen O. Deantonis, Scott Kahan
• Year of Publication: 2007
• Copyright Details: In A Page: Pediatric Signs and Symptoms, Copyright © 2007 Lippincott Williams & Wilkins.

Other Book Chapters Related to Hair symptoms

Read excerpts from these other book chapters related to Hair symptoms:

Copyright Details: In A Page: Pediatric Signs and Symptoms, Copyright © 2008 Williams & Wilkins.

More About Causes of Hair symptoms

• Back to symptom: Hair symptoms: Introduction (review 645 causes)
• Next Book Extract About Hair symptoms: Hirsutism (In A Page: Pediatric Signs and Symptoms)
• All Book Extracts: All Online Book Extracts for Hair symptoms

More About This Book: Title: In A Page: Pediatric Signs and Symptoms Authors: Jonathan E. Teitelbaum, Kathleen O. Deantonis, Scott Kahan Publisher: Lippincott Williams & Wilkins Copyright: 2007 ISBN: 1-4051-0427-9

 » Next page: Hirsutism (In A Page: Pediatric Signs and Symptoms)

Rate This Website

What do you think about the features of this website? Take our user survey and have your say:

Website User Survey

Medical Tools & Articles:

Next articles:

• Hirsutism (In A Page: Pediatric Signs and Symptoms)
• HIRSUTISM (Differential Diagnosis in Primary Care)
• Alopecia (A Pocket Manual of Differential Diagnosis)
• Hirsutism and Generalized Hypertrichosis (A Pocket Manual of Differential Diagnosis)
• Alopecia (Professional Guide to Diseases (Eighth Edition))

Tools & Services:

• Bookmark this page
• Take a survey relating to Hair symptoms
• Symptom Search
• Symptom Checker
• Medical Dictionary
• Give your feedback

Medical Articles:

• Disease & Treatments Search
• Misdiagnosis Center
• Full list of interesting articles

Forums & Message Boards

• Ask or answer a question at the Boards:
• I cannot get a diagnosis. Please help.
• Tell us your medical story.
• Share your misdiagnosis story.
• What is the best treatment for my condition?
• See all the Boards.

Enter your search terms Submit search form
Search The Web Search wrongdiagnosis.com

Common Health Mistakes

Symptom
Checker

Search Specialists by State and City