|
|
(38 intermediate revisions by 9 users not shown) |
Line 4: |
Line 4: |
| Image = Alopecia.jpg| | | Image = Alopecia.jpg| |
| Caption = Alopecia as male pattern baldness at age 40| | | Caption = Alopecia as male pattern baldness at age 40| |
| DiseasesDB = 14765 |
| |
| ICD10 = {{ICD10|L|65|9|l|60}} |
| |
| ICD9 = {{ICD9|704.09}} |
| |
| ICDO = |
| |
| OMIM = |
| |
| MedlinePlus = 003246 |
| |
| MeshID = D000505 |
| |
| }} | | }} |
| {{Alopecia}} | | {{Alopecia}} |
| | '''For patient information, click [[Alopecia (patient information)|here]]''' |
|
| |
|
| {{CMG}} | | {{CMG}}; {{AE}} {{KS}} [[Ogechukwu Hannah Nnabude, MD]] |
|
| |
|
| {{SK}} Bald; balding; baldness; atrichia; hair loss; hypotrichosis | | {{SK}} Atrichia; hair loss; bald; baldness; balding; hypotrichosis |
| | | |
| ==Overview== | | ==[[Alopecia overview|Overview]]== |
| '''Alopecia''' is the resulting condition from the loss of hair, which is termed ''effluvium.'' It should be distinguished from [[baldness]], which is the ''lack'' of hair, including contexts where that absence is intentional. (In some cases the terms are used interchangeably, and in some conditions such as [[trichotillomania]], where the loss of the hair is due to intentional acts, but the motive for that act is defined as a medical condition, it can be difficult to determine whether the label "alopecia" is appropriate.)
| |
|
| |
|
| Alopecia is characterized by scarring or non-scarring. Scarring alopecia is caused by numerous dermatologic factors, including glabrous skin (non-hairy), and is very difficult to diagnose and manage. Non-scarring alopecia is characterized by the absence of visible inflammation of the skin involved. | | ==[[Alopecia historical perspective|Historical Perspective]]== |
|
| |
|
| == Vocabulary == | | ==[[Alopecia classification|Classification]]== |
| *[[Anagen]]:growth phase, lasts 2-3 years (80-90% of follicles at any given time)
| |
| *[[Catagen]]:involutional phase, lasts 2-3 weeks (1-3% of follicles)
| |
| *Telogen:resting phase, lasts 3-4 months (5-10% of follicles)
| |
| :*hair released from shaft and shed at end of telogen new cycle begins
| |
| :*mature root sheath of telogen hair = “club” at proximal end
| |
| *[[Terminal hair]]s: large shaft diameters, bulbs extend into subcutaneous fat
| |
| *[[Vellus hair]]s:smaller in caliber and length, less pigmented
| |
| *Indeterminate hairs:size/length between that of terminal and vellus hairs
| |
|
| |
|
| == Risk Factors == | | ==[[Alopecia pathophysiology|Pathophysiology]]== |
|
| |
|
| *[[Drugs]]:
| | ==[[Alopecia causes|Causes]]== |
| :*[[anticoagulants]]
| |
| :*[[anticonvulsants]]
| |
| :*[[antidepressants]]
| |
| :*[[beta-blockers]]
| |
| *[[Medical illness]]
| |
| :*[[Hyperthyroidism|Hyper]]/[[hypothyroidism]]
| |
| :*[[Nutritional deficiencies]]: [[iron]], [[zinc]], [[protein]]
| |
| :*[[Connective tissue]] disorders: [[SLE]], [[dermatomyositis]]
| |
|
| |
|
| == Pathophysiology & Etiology== | | ==[[Alopecia differential diagnosis|Differentiating Alopecia from other Diseases]]== |
| '''Non Scarring'''<br>
| |
| ''Diffuse''
| |
| *[[Androgenetic alopecia]]
| |
| :*most common (30-40% of men and women)
| |
| :*Genetically determined: [[polygenic]] with [[variable penetrance]]
| |
| :*Shortening of anagen phase follicular miniaturization
| |
| :*Men: M-shaped pattern along frontal hairline (temporal loss progresses to midscalp)
| |
| :*Women: more diffuse, can be difficult to distinguish from telogen effluvium
| |
| *[[Telogen effluvium]]
| |
| :*Reversible loss of mature, terminal hairs (few hundred per day)
| |
| :*[[Stress]]ful event (or [[medication]]) triggers transition of more anagen hairs into telogen phase
| |
| ::*[[Childbirth]], [[fever]], severe [[infection]], severe [[psychologic stress]], major [[surgery]], [[crash diet]]
| |
| ::*[[Drugs]]: [[heparin]], [[antithyroid agents]], [[anticonvulsants]], [[hormones]]
| |
| :*Diffuse hair loss peaks 3-4 months after inciting event
| |
| :*Up to 30% of hairs must be lost before cosmetically apparent
| |
| *Anagen effluvium
| |
| :*Acute loss of anagen hair = 80-90% of hair
| |
| :*Occurs 10-14 days after treatment with [[antimitotic agents]] ([[chemo]])
| |
| ''Focal''
| |
| *[[Alopecia areata]]: incidence 1/1000
| |
| :*Smooth, discrete, circular areas of complete hair loss occurring over a few weeks
| |
| :*Exclamation point hairs: hair root narrower than normal with less pigment
| |
| :*Can occur on any hair-bearing area; nails may also have proximal pitting
| |
| :*Usually reversible: regrowth occurs over several months; 90% regrow within 2 years
| |
| :*Relapse occurs in up to 1/3
| |
| :*Decreased chance of regrowth/increased risk relapse if:
| |
| ::*Prepubertal onset
| |
| ::*Widespread involvement ([[alopecia totalis]] or [[Alopecia universalis|universalis]])
| |
| ::*Duration > 5 years
| |
| ::*History of [[atopy]]
| |
| :*Possible [[autoimmune]] mechanism: bx shows [[T-cell]] infiltrates around hair follicles
| |
| :*Positive [[family history]] in 20%
| |
| *[[Syphilis]]
| |
| :*Moth-eaten, patchy pattern of loss (may be diffuse)
| |
| :*May be associated with [[skin lesions]] of [[secondary syphilis]], or may occur in [[Latent syphilis|latent stage]]
| |
| :*Full hairgrowth occurs after treatment of [[infection]]
| |
| *[[Trauma]]
| |
| :*[[Traction alopecia]]: due to hairstyles that impose chronic tension on hair (braids)
| |
| :*Hair loss most prominent in areas of greatest tension (margins)
| |
| :*Fine, [[vellus hair]]s present in areas of absent [[terminal hair]]s
| |
| :*Regrowth can occur in early disease (few months-yrs), but not in late disease (years)
| |
| :*Chemical trauma: repeated use of [[lye]]-containing straightening agents or hot oils for styling
| |
| :*[[Trichotillomania]]: bizarre, asymmetric pattern of broken hairs of varying length
| |
| '''Scarring'''
| |
| *uncommon; hair loss is permanent
| |
| *erythematous papules, pustules, or scaling centered around follicles
| |
| *polytrichia = multiple hair shafts exiting a single enlarged orifice
| |
| *eventual obliteration of follicular orifices
| |
| *[[Tinea capitis]]
| |
| :*Scaling and [[inflammation]] in patchy areas of hair loss, +/- [[lymphadenopathy]]
| |
| :*Usually in children
| |
| :*KOH prep positive
| |
| *Central, centrifugal scarring alopecia (a.k.a. follicular degeneration syndrome, pseudopelade)
| |
| :*Symmetric involvement of central portion of scalp with outward expansion over months/yrs
| |
| :*May be associated with pustules (folliculitis decalvans)
| |
| :*Cause unknown-> emipiric [[Rx]] with [[steroids]], [[antibiotics]]
| |
| *[[Discoid lupus]]
| |
| :*[[Inflammation]] with plugged follicles, scale, abnormal scalp pigmentation
| |
| :*May have discoid [[lesion]]s elsewhere on body
| |
|
| |
|
| == Diagnosis ==
| |
|
| |
|
| *Pull test: firm pull on 20-40 hairs should yield fallout of no more than 1 in 10 hairs
| | ==[[Alopecia epidemiology and demographics|Epidemiology and Demographics]]== |
| :*Increased # telogen hairs with depigmented proximal bulb: [[telogen effluvium]]
| |
| :*Increased # hairs with no bulb: breakage (hair fragility due to exogenous injury)
| |
| :*[[Anagen hair]]s with pigmented root: likely excessive force
| |
| *Follicular units: number of hairs produced per follicular orifice
| |
| :*Threes = normal for ages 20-40
| |
| :*Twos = normal for ages 40-60
| |
| :*Ones = normal for ages >60
| |
| :*Voids = follicular orifices w/o hairs suggests advanced [[androgenetic alopecia]] if no scarring
| |
|
| |
|
| *Testing:minimal
| | ==[[Alopecia risk factors|Risk Factors]]== |
| :*[[Medical illness]] suspected: [[CBC]], [[TSH]], possibly [[ferritin]]
| |
| :*[[RPR]] if patchy or unexplained loss
| |
| :*KOH prep if patchy alopecia with scaling or [[inflammation]]
| |
|
| |
|
| ==Complete Differential Diagnosis for Alopecia== | | ==[[Alopecia natural history, complications and prognosis|Natural History, Complications and Prognosis]]== |
| === Non-Scarring Alopecia ===
| |
| * [[Adrenocortical insufficiency]] (primary or secondary)
| |
| * [[Anagen]] effluvium (anagen=growing hair)
| |
| * [[Cushing's syndrome]]
| |
| * Diffuse hair thinning due to [[metabolic]] causes
| |
| * [[Hyperthyroidism]]
| |
| * [[Hypoparathyroidism]]
| |
| * [[Hypothyroidism]]
| |
| * [[Pituitary insufficiency]]
| |
| * [[Secondary syphilis]]
| |
| * [[Sheehan's syndrome]]
| |
| * Temporary hair loss
| |
| *:* [[Pregnancy]]
| |
| *:* [[Malnutrition]]
| |
| *:*:* [[Malabsorption]]
| |
| *:*:* [[Protein deficiency]]
| |
| *:*:* [[Tryptophan]] deficiency
| |
| *:*:* [[Nontropical sprue]]
| |
| *:*:* [[Vitamin A deficiency]]
| |
| *:*:* [[Vitamin B deficiency]]
| |
| *:*:* [[Vitamin D deficiency]]
| |
| *:*:* [[Rickets]]
| |
| * [[Telogen effluvium]] (telogen=resting hair)
| |
| * [[Thyroiditis]]
| |
| * [[Trichotillomania]]
| |
|
| |
|
| === Scarring Alopecia === | | ==Diagnosis== |
| * [[Amyloidosis]]
| | [[Alopecia diagnostic study of choice|Diagnostic study of choice]] | [[Alopecia history and symptoms|History and Symptoms]] | [[Alopecia physical examination|Physical Examination]] | [[Alopecia laboratory findings|Laboratory Findings]] | [[Alopecia electrocardiogram|Electrocardiogram]] | [[Alopecia x ray|X-Ray Findings]] | [[Alopecia echocardiography and ultrasound|Echocardiography and Ultrasound]] | [[Alopecia CT scan|CT-Scan Findings]] | [[Alopecia MRI|MRI Findings]] | [[Alopecia other imaging findings|Other Imaging Findings]] | [[Alopecia other diagnostic studies|Other Diagnostic Studies]] |
| * Chronic disciform [[lupus erythematosis]]
| |
| * [[Congenital defect]]s
| |
| * [[Discoid Lupus Erythematosus]]
| |
| * Dissecting [[cellulitis]]
| |
| * [[Herpes zoster infection]]
| |
| * [[Infection]]
| |
| *:* [[Favus]]
| |
| *:* [[Typhoid Fever]]
| |
| *:* [[Leptospirosis]]
| |
| *:* [[Secondary syphilis]]
| |
| * Inflammatory [[dermatoses]]
| |
| * [[Lichen planopilaris]]
| |
| * [[Lymphoma]]
| |
| * [[Morphea]]
| |
| * [[Mycosis fungoides]]
| |
| * [[Neoplasm]]
| |
| * [[Neurodermatitis]]
| |
| * Physical or chemical agents:
| |
| *:* [[ACE inhibitors]]
| |
| *:* [[Allopurinol]]
| |
| *:* [[Androgens]]
| |
| *:* [[Anticoagulants]]
| |
| *:* [[Anticonvulsants]]
| |
| *:* [[Antimycotic agents]]
| |
| *:* [[Arsenic]]
| |
| *:* [[Azathioprine]]
| |
| *:* [[Beta blockers]]
| |
| *:* [[Borates]]
| |
| *:* [[Cadmium]]
| |
| *:* [[Chemotherapeutics]]
| |
| *:* [[Chlorambucil]]
| |
| *:* [[Cisplatin]]
| |
| *:* [[Clofibrate]]
| |
| *:* [[Cyclophosphamide]]
| |
| *:* [[Cytarabine]]
| |
| *:* [[Estrogens]]
| |
| *:* [[Fluororacil]]
| |
| *:* [[Gentamycin]]
| |
| *:* [[Gold compounds]]
| |
| *:* [[Heparins]]
| |
| *:* [[Indomethacin]]
| |
| *:* [[Levodopa]]
| |
| *:* [[Linolic acid]]
| |
| *:* [[Mercury]] and derivatives
| |
| *:* [[Methotrexate]]
| |
| *:* [[Niacin]]
| |
| *:* [[Oral contraceptives]]
| |
| *:* [[Propranolol]]
| |
| *:* [[Retinoids]]
| |
| *:* [[Salicylates]]
| |
| *:* [[Selenium]]
| |
| *:* [[Squalenes]]
| |
| *:* [[Steroids]]
| |
| *:* [[Thallium]]
| |
| *:* [[Undecylenic acid]]
| |
| *:* [[Vitamin A overdose]]
| |
| *:* [[Warfarin]]
| |
| * [[Pseudofolliculitis barbae]]
| |
| * [[Psoriasis]]
| |
| * [[Sarcoidosis]]
| |
| * [[Scleroderma]]
| |
| * [[Systemic Lupus Erythematosus]]
| |
| | |
| === Miscellaneous ===
| |
| * [[Addison's Disease]]
| |
| * [[Anemia]]
| |
| * [[Cancer]]
| |
| * [[Diabetes Mellitus]]
| |
| * [[Pneumonia]]
| |
| * [[Scarlet Fever]]
| |
| * [[Schmidt's Syndrome]]
| |
| * [[Stress (medicine)|Stress]]
| |
| *:* [[Childbirth|Labor]]
| |
| *:* [[Surgery]]
| |
| * [[Androgen insensitivity syndrome|Testicular feminization syndrome]]
| |
| * [[Turner's Syndrome]]
| |
| * [[Typhoid fever]]
| |
| * Mechanical effects
| |
| :* Traction alopecia
| |
| :* Pressure alopecia
| |
| :*: Alopecia after extended bed rest
| |
| :* Trichotillomania (compulsion to pull out one’s own hair)
| |
| | |
| == History and Symptoms ==
| |
| *Age
| |
| :*Childhood: only 2 common diagnoses [[tinea capitis]], [[alopecia areata]]
| |
| :*Adulthood: [[tinea capitis]] rare; all the rest possible
| |
| *Duration
| |
| :*<1 year: suggests [[telogen effluvium]] if diffuse loss
| |
| :*>1 year: suggests [[androgenetic alopecia]] if diffuse loss
| |
| :*Pattern of loss
| |
| :*Shedding: “lots of hair coming out,” may be due to hair breakage or loss by the root
| |
| :*Thinning: scalp more visible without noticeable hair fallout, suggests [[androgenetic alopecia]]
| |
| :*[[Family history]]: may be positive in [[androgenetic alopecia]], [[alopecia areata]]
| |
| :*Grooming practices: can cause hair fragility/breakage
| |
| :*Chemical treatments (relaxers, perms, bleaching) most damaging; hair dye less so
| |
| Traction styling<br>
| |
| | |
| == Physical Examination ==
| |
| | |
| === Appearance of the Patient ===
| |
| *[[Scalp]]
| |
| :*Normal or with features of [[scarring]]
| |
| :*if scalp abnormal provide clues to dx
| |
| ::*scaling
| |
| ::*[[erythema]]
| |
| ::*[[pustules]]
| |
| ::*dyspigmentation
| |
| *Pattern: diffuse or patchy
| |
| :*Male pattern (diffuse):bitemporal recession +/or vertex loss
| |
| :*Female pattern (diffuse):coronal thinning with preserved anterior hairline
| |
| :*Patchy:with preserved hair of variable length (breakage)
| |
| ::*with exclamation point hairs ([[alopecia areata]])
| |
| ::*with no hair ([[scarring]], traction, [[syphilis]], [[tinea]])
| |
| *Patient may also have nails that have a hammered brass appearance.
| |
| | |
| == Laboratory Findings ==
| |
| * [[Viral culture|Viral]] and [[bacterial cultures]]
| |
| * [[Prolactin]]
| |
| * [[Thyroid function tests]]
| |
| * [[Iron]] studies
| |
| * [[Dehydroepiandrosterone-sulfate]] ([[DHEA-S]])
| |
| * [[Testosterone]]
| |
| * [[Rapid plasma reagin]] ([[RPR]])
| |
| * [[Erythrocyte sedimentation rate]] ([[ESR]])
| |
| * [[Antinuclear antibodies]] ([[ANA]])
| |
|
| |
|
| ==Treatment== | | ==Treatment== |
| * Goal of [[treatment]] is to avoid future hair loss.
| | [[Alopecia medical therapy|Medical Therapy]] | [[Alopecia surgery|Surgery]] | [[Alopecia primary prevention|Primary Prevention]] | [[Alopecia secondary prevention|Secondary Prevention]] | [[Alopecia cost-effectiveness of therapy|Cost-Effectiveness of Therapy]] | [[Alopecia future or investigational therapies|Future or Investigational Therapies]] |
| * [[Scarring]] hair loss prevents hair from going back.
| |
| * Wigs and [[hair transplants]]
| |
| * Anagen effluvium
| |
| *:* Treat [[illness]] or withdraw [[drug]]
| |
| * [[Telogen effluvium]]
| |
| *:* [[Stress]] the recovery is normal
| |
| * Treat underlying cause of alopecia
| |
| | |
| == Pharmacotherapy ==
| |
| | |
| === Acute Pharmacotherapies ===
| |
| * [[Androgenetic alopecia]]
| |
| *:* For men, oral [[finasteride]] or [[topical]] [[minoxidil]]
| |
| *:* For women, [[antiandrogens]] if [[adrenal]] [[androgens]] are increased
| |
| * [[Tinea capitus]]/[[kerion]]
| |
| *:* Oral [[antifungals]]
| |
| * [[Alopecia areata]]
| |
| *:* [[Glucocorticoids]]
| |
| *:* [[Psoralen and ultraviolet A]] ([[PUVA]])
| |
| *:* Superpotent [[steriods]]
| |
| *:* [[Cyclosporine]]
| |
| *:* Intralesional [[steriod]] [[injections]]
| |
| | |
| === Chronic Pharmacotherapies ===
| |
| *Topical [[minoxidil]] ([[Rogaine]], generic):
| |
| :*only [[Rx]] approved for women as well as men
| |
| :*Increases duration of [[anagen]] and enlarges miniaturized follicles
| |
| :*Mechanism unclear
| |
| *Efficacy:
| |
| :*hair counts ~5x higher than placebo with use of 5% solution (men)
| |
| :*hair counts 45% higher with use of 5% solution compared with use of 2% solution (men)
| |
| :*hair counts returned to those of placebo group within 24 weeks after discontinuation [[Rx]] (men)
| |
| :*women: increased hair growth in 60% vs. 40% with use of 2% soln vs. placebo
| |
| :*'''Advice for patients:'''
| |
| ::*1 mL bid applied to dry [[scalp]] with spray or dropper; spread lightly w/finger
| |
| ::*expect decreased loss w/in 2 mos, growth w/in 4-8 mos; stable at 1-1.5 yrs
| |
| ::*best results if baldness present at vertex x < 5 years and < 10 cm diameter
| |
| ::*cosmetically notable growth occurs in only 30-40%
| |
| ::*Rx must continue indefinitely or regrown hair will be lost
| |
| ::*[[Side effect]]s = rare contact or irritant dermatitis; no change [[blood pressure]], [[heart rate]] or weight
| |
|
| |
|
| == Acknowledgements == | | == Acknowledgements == |
| The content on this page was first contributed by: Steven Wiviott, M.D. | | The content on this page was first contributed by: Steven Wiviott, M.D. |
|
| |
| ==References==
| |
| [http://www.calosol.com/alopecia.php Alopecia Types] - More information about alopecia and the various different types{{reflist}}
| |
| <br>
| |
|
| |
|
| [[ro:Alopecia]] | | [[ro:Alopecia]] |