Alopecia

    Intro

    • Three phases of hair growth
      • anagen - hair grows (90% hairs are in this phase)
      • catagen - apoptosis of cells (hair at end of cycle)
      • telogen - hair falls out, stem cells turn on, and goes to anagen again.
    • Alopecia defined as:
      • Non-scarring - reversible, hair follicles preserved.
      • Scarring - usually irreversible, hair follicles destroyed.

    Non-scarring 

    • follicular openings can be seen

     

    Androgenetic Alopecia

    • most common
      • 25-30% women, 50% men at age 50.
      • In Men:
        • Androgens play key role (hair follicles sensitive to androgens)
        • Gnetics have important role
        • hair loss in temples or vertex - Hamilton Norwood Scale
      • In Women
        • Not Androgenetic** - androgens play different role
        • thinning over frontal scalp, may have acne/hirsutism, front hairline is usually normal - Ludwig scale
      • Progressive hair miniturization (hairs still there, but smaller - "exclamation hairs"?
      • Labs: CBC, TSH, ferritin, DHEAS+free/totalTestosterone if acne or hirsutism
    • Tx:
      • Women:
        • Minoxidil 2% or 5% - 1mL twice daily (topical)
          • Works by increasing blood flow to scalp
        • Spironolactone if elevated androgens (blocks androgens) + OCP
        • Hair transplant, hairpieces.
      • Men:
        • Minoxidil 5% 1cc twice daily (topical)
        • Finasteride -1mg po od - works in most, regrows new hair.
          • 5alpha-reductase type II inhibitor - inhibits testosterone --> DHT (miniturization of hair)
        • Hair transplant.

     

    Alopecia Areata

    • Loss of some scalp hair - patches
    • Autoimmune attack on hair bulb (bulb is at bottom of hair shaft, stem cells are closer to the top - preserved)
    • Symptoms
      • Often no sx (no itching/ burning/pain)
      • Nail pitting is common.
    • Can be associated with:
      • Atopy (40%)
      • Thyroid (10%)
      • Vitiligo (up to 7%)
      • Others: pernicious anemia, etc..
    • Labs: TSH, CBC, Free T4, ferritin (all hair pts), B12
    • May loss some body hair
    • Types:
      • Alopecia totalis (AT) - Loss of all scalp hair, some body hair remains.
      • Alopecia universalis (AU) - loss of all scalp and body hair
      • Ophiasis pattern of AA - back of scalp hairline ascending.
    • Tx:
      • >50% of localized AA will spontaneously improve, many will have another episode later in life.
      • if <50% of hair loss
        • Topical Class I steroids and intralesional steroid injections.
        • Minoxidil 5% 1cc bid
      • if >50% loss
        • Immunotherapy with topical DPCP (diphencyprone)
      • If all fails - try systemic:
        • Prednisone
        • Cyclosporine
        • Methotrexate
        • Sulfasalazine

    Telogen Effluvium 

    • Some trigger causes hair follicles to go into telogen phase and fall out. (I.e. Hypothyroidism.)
      • Very diffuse, patients report "clogged drains", hair on clothes.
      • Can start 3mo after trigger.
    • Most of us have had telogen effluvium episodes in our life.
    • Triggers acronym: S.E.N.D  (bold- most common)
      • S - Stress & Scalp Disease (Stress - surgery)
      • E - Endocrine (Hypothyroidism, Post-partum)
      • N - Nutritional (Iron Deficiency)
      • D - Drugs
        • SSRI, B-blockers
        • Acitretin, Heparin, Lithium, Interferon, Terbinafide, Valproic acid.
    • Can do positive "pull test"
      • Gently pull 50 hairs, if >5 come out, positive*
    • Labs: CBC, TSH, (+/- free T4), Ferritin (ensure >40)
      • Can also do ANA, Zinc, VDRL... etc..
    • Tx:
      • Identify trigger.  Once stop trigger, resolves in ~6mo.

    Other

    • Tractional Alopecia - pulls hair back, often reversible.
    • Trichotillomania (hair pulling)
    • Tinea capitis - Trichophyton tonsurans most common
      • need oral antifungals (not topical), i.e. Terbinafide oral.
      • Scan scar permanently if chronic.

    Scarring - Cicatricial Alopecia

    • follecular openings are missing
    • PRIMARY - hair follicle immune attacked.
      • (ones described below)
    • SECONDARY - hair follicle bystander of inflammation around.
      • (usually radiation, drugs, cancers, trauma, etc..)
    • Both lead to permanent destruction.
    • Classified by inflammation cell seen

    Lymphotytic

    Lichen planopilaris

    • Rare, but most common scarrin alopacia
    • Autoimmune - lymphocyte attack
    • Often symptomatic
      • Itching, burning, pain in scalp.
      • Perifollicular erythema.
    • Do scalp biopsy.
    • Tx:
      • Topical steroids, injections.
      • Systemic meds (Isotretinoin, doxycycline etc..)

    Frontal Fibrosing Alopecia

    • Varient of Lichen Planopilaris.
    • Loss of frontal hairline.
    • Symptomatic - redness, itching, burning.

    Central centrifugal cicatricial alopecia (CCCA)

    • Common in black women.
    • Usually asymptomatic.

    Discoid Lupus Erythematosis

    • DLE - scalp usually first site (can be other sites first).
    • Depigmented areas of scarring.

    Neutrophilic

    Folliculitis decalvans

    • Most common neutrophilic.
    • Itching, pain, discharge of pus, commonly vertex.
    • Tx: doxycycline + other abx.

    Dissecting Cellulitis

    • Young black men
    • Itching, burning, pain , discharge.
    • Follicular occlusion
    • Tx: Isotretinoin (reduces follicular keratinization and occlusion).  Does not grow S. aureus.
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