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Disorders of hair

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Disorders of hair Less hair Excessive hair * Presentation The common pattern in men is the loss of hair first from the temples, and then from the crown However, in ... – PowerPoint PPT presentation

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Title: Disorders of hair


1
Disorders of hair
  • Less hair
  • Excessive hair

2
  • The hair can be divided into three parts
  • (1) The bulb
  • A swelling at the base which originates from
    the dermis
  • (2) The root
  • The hair lying beneath the skin surface
  • (3) The shaft
  • Which lies above the skin surface.

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  • In cross-section,
  • (1) The medulla
  • An area in the core which contains loose cells
    and airspaces
  • (2) The cortex
  • Which contains densely packed keratin and
  • (3) The cuticle
  • Which is a single layer of cells arranged like
    roof shingles.

5
Classification
  • Hairs are classified into three main types
  • Lanugo hair
  • Vellus hair
  • Terminal hair
  • Terminal hairs convert to vellus hairs in male
    pattern alopecia
  • Vellus hairs convert to terminal hairs in
    hirsutism.

6
  • Lanugo hair
  • Fine long hair covering the foetus
  • Shed about 1 month before birth unless born
    prematurely.
  • May reappear sometimes in severe malnutrition and
    anorexia nervosa.

7
  • Vellus hair
  • Fine, short unmedullated hair covering much of
    the body surface.
  • They replace the lanugo hair just before birth.

8
  • Terminal hair
  • Fully developed
  • Long coarse medullated hair in the scalp or pubic
    regions.
  • Their growth is influenced by circulating
    androgen levels.

9
The hair cycle
  • Each follicle passes through regular cycles of
    growth and shedding.
  • There are three phases of follicular activity
  • Anagen
  • The active phase of hair production.
  • Catagen
  • A short phase of conversion from active growth to
    the resting phase.
  • Growth stops, and the end of the hair becomes
    club-shaped.
  • Telogen
  • A resting phase at the end of which the club hair
    is shed.

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  • The duration of each of these stages varies from
    region to region.
  • On the scalp it is said to contain an average of
  • 100,000 hairs
  • Anagen lasts for upto 5 years
  • Catagen for about 2 weeks
  • Telogen for about 3 months
  • As many as 100 hairs may be shed from the normal
    scalp every day as a normal consequence of
    cycling.

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Alopecia
  • The term alopecia means loss of hair
  • Alopecia has many causes and patterns.
  • One convenient division is into
  • Localized
  • Diffused
  • It is also important to decide if the hair
    follicles are replaced by scar tissue if they
    have, regrowth cannot occur.

14
CLASSIFICATION OF ALOPECIA
  • Diffuse
  • Androgenetic alopecia
  • Telogen effluvium
  • Metabolic
  • Hypothyroidism
  • Hyperthyroidism
  • Hypopituitarism
  • Diabetes mellitus
  • HIV disease
  • Nutritional deficiency
  • Liver disease
  • Post-partum
  • Alopecia areata
  • Syphilis
  • Discoid lupus erythematosus
  • Radiotherapy
  • Folliculitis decalvans
  • Lichen planus pilaris
  • Localised
  • Non-scarring
  • Tinea capitis
  • Alopecia areata
  • Androgenetic alopecia
  • Traumatic (trichotillomania, traction, cosmetic)
  • Syphilis
  • Scarring
  • Idiopathic
  • Developmental defects
  • Discoid lupus erythematosus
  • Herpes zoster
  • Pseudopelade

15
Localized alopecia
  • Alopecia areata

16
Etiology
  • An immunological basis is suspected because of an
    association with
  • Autoimmune thyroid disease
  • Pernicious anemia
  • Vitiligo
  • Atopy
  • Histologically, T lymphocytes cluster like a
    swarm of bees around affected hair bulbs because
    cytokines produced by the dermal papillae in
    lesions not only attract lymphocytes to
    perifollicular region but also stimulate them to
    multiply

17
  • Alopecia areata is probably inherited as a
    complex genetic trait
  • Sometimes HLA-DQ3, -DR11 or -DR4 act as
    susceptibility factors
  • With an increased occurrence in the first-degree
    relatives of affected subjects and twin
    concordance.
  • It affects some 10 of patients with Downs
    syndrome, suggesting the involvement of genes on
    chromosome 21.
  • Environmental factors as well as emotional
    factors may trigger alopecia areata in the
    genetically predisposed.

18
Epidemiology
  • AA is the common type
  • Both gender affected
  • Can start at any age

19
Presentation
  • A typical patch of hair loss area is uninflamed,
    with no scaling, but with empty hair follicles
  • Pathognomonic exclamation-mark hairs may be
    seen around the edge of enlarging areas.
  • They are broken off about 4 mm from the scalp
  • Are narrowed and less pigmented proximally

20
  • Incidence is most common in the scalp and beard
    but other areas, especially the eyelashes and
    eyebrows, can be affected too.
  • An uncommon diffuse pattern is recognized, with
    exclamation-mark hairs scattered widely over a
    diffusely thinned scalp.
  • Up to 50 of patients show fine pitting or
    wrinkling of the nails.

21
The characteristic uninflamed patches of alopecia
areata.
22
Exclamation-mark hairs Pathognomonic of alopecia
areata.
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24
Course
  • The outcome is unpredictable.
  • In a first attack, regrowth is usual within a few
    months.
  • New hairs appear in the centre of patches as fine
    pale down, and gradually regain their normal
    colour
  • The new hair may remain white in older patients.
  • Fifty percent of cases resolve spontaneously
    without treatment within 1 year
  • Only 10 have severe chronic disease
  • Subsequent episodes tend to be more extensive
  • Regrowth is slower.

25
  • Hair loss in some areas may coexist with regrowth
    in others.
  • A few of those who go on to have chronic disease
    loose all the hair from their heads (alopecia
    totalis) or from the whole skin surface (alopecia
    universalis).
  • other variant is ophiasis which is lose of hair
    in a band like patternat the periphery of scalp
  • Regrowth is tiresomely erratic but the following
    suggest a poor prognosis
  • 1. Onset before puberty
  • 2. Association with Atopy or Downs syndrome
  • 3. Unusually widespread alopecia and
  • 4. Involvement of the scalp margin
    (ophiasiform type)

26
Alopecia totalis
Alopecia universalis
27
Differential diagnosis
  • Ringworm infection
  • Lupus erythematosus
  • Lichen planus
  • Hair-pulling habit of children
  • Traction alopecia
  • Secondary
  • Pseudopelade

28
Investigations
  • None are usually needed.
  • The histology of bald skin shows lymphocytes
    around and in the hair matrix.
  • Syphilis can be excluded with serological tests
  • Organ-specific autoantibody screens

29
Treatment
  • A patient with a first or minor attack can be
    reassured about the prospects for regrowth.
  • Topical corticosteroid creams of high potency can
    be prescribed
  • The use of systemic steroids should be avoided in
    most cases
  • Intradermal injection of 0.2 ml intralesional
    triamcinolone acetonide (510 mg/ml), raising a
    small bleb within an affected patch, leads to
    localized tufts of regrowth.
  • Side effects? dermal atrophy evident as
    depressed areas at the sites of injections.

30
Regrowth within a patch of alopecia areata
after a triamcinolone injection.
31
  • Ultraviolet radiation or even psoralen with
    ultraviolet A (PUVA) therapy may help in
    extensive cases, but hair fall often returns when
    treatment is stopped.
  • Contact sensitizers (e.g. diphencyprone) seemed
    promising but the long-term effect of persistent
    antigen stimulation is worrying they are still
    being used only in a few centres under trial
    conditions.
  • Wigs are necessary for extensive cases.

32
A trial of diphencyprone to one side of the
scalp caused some regrowth
33
Androgenetic alopecia (male-pattern baldness)
  • Cause
  • It is because of miniaturization of hair
    follicles
  • Although clearly familial, the exact mode of
    inheritance has not yet been clarified.
  • Male-pattern baldness is androgen dependent
  • In females, androgenetic alopecia (female-pattern
    hair loss), with circulating levels of androgen
    within normal limits, is seen only in those who
    are strongly predisposed genetically.

34
Presentation
  • The common pattern in men is the loss of hair
    first from the temples, and then from the crown
  • However, in women the hair loss may be much more
    diffuse, particularly over the crown
  • In bald areas, terminal hairs are replaced by
    finer vellus ones.

35
Androgenetic alopecia beginning in the frontal
area
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38
Complications
  • Anxiety
  • Bald scalps burn easily in the sun
  • It has been suggested recently that bald men are
    more likely to have a heart attack and prostate
    cancer than those with a full head of hair

39
Differential diagnosis
  • The diagnosis is usually obvious in men, but
    other causes of diffuse hair loss have to be
    considered in women

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Treatment
  • Scalp surgery
  • Hair transplants
  • Wigs
  • Topical application of minoxidil lotion may slow
    early hair loss and even stimulate new growth of
    hair but the results are not dramatic
  • Small and recently acquired patches respond best.
  • When minoxidil treatment stops, the new hairs
    fall out after about 3 months.
  • Antiandrogens help some women with the diffuse
    type of androgenetic alopecia.

42
Treatment
  • Finasteride (Propecia), an inhibitor of human
    type II 5a-reductase, reduces serum and scalp
    skin levels of dihydrotestosterone in balding men
    and at the dosage of 1 mg/day, it may increase
    hair counts
  • Lead to a noticeable improvement in both frontal
    and vertex hair thinning.
  • However, the beneficial effects slowly reverse
    once treatment has stopped.
  • This treatment is not indicated in women or
    children.
  • Side-effects are rare, but include
  • Decreased libido, erectile dysfunction and
    altered prostate-specific antigen levels

43
Telogen effluvium
  • All the hair follicle are not synchronous in
    their cycle
  • If anagen phase of several adjoining hair
    follicles is aborted and these follicles enter
    telogen phase at the same time and several hair
    are shed simultaneously this is called telogen
    effluvium

44
  • Etiology
  • Infections typhoid, malaria, dengue
  • Childbirthprolonged
  • Surgical trauma
  • Haemorrhage
  • Emotional stress

45
  • Clinical features hair loss occurs after 2-3mths
    after the precipitating factor
  • Severe cases associated with anemia and beaus
    lines of the nails.
  • Treatment stops spontaneously after2-3mths

46
Excessive hair
  • Hypertrichosis
  • Hirsutism

47
Hirsutism and hypertrichosis
  • Hirsutism is the growth of terminal hair in a
    woman which is distributed in a pattern normally
    seen in a man (for example, mustache, beard,
    central chest, shoulders, lower abdomen, back,
    and inner thighs).
  • Hypertrichosis is an excessive growth of terminal
    hair in either sex that does not follow an
    androgen-induced pattern

48
Types of hypertrichosis
  • Congenital Hypertrichosis is very rare.
  • A fetus is covered with lanugo and it does not
    fall off but continues to grow.
  • Acquired Hypertrichosis
  • Occurs after birth.
  • Unpigmented vellus hair or pigmented terminal
    hair.
  • The excessive hair may cover the entire body
    (Generalized), or it could be localized to one
    area.

49
  • Congenital Localized forms
  • Hypertrichosis cubiti (Congenital hairs on
    elbows)
  • Hairy pinna (Congenital hairs on the external
    ears)

50
Acquired hypertrichosis
51
Causes of hypertrichosis
  • Localized
  • Melanocytic naevi
  • Beckers naevi
  • Satyrs tuft in sacral area- in patients with
    spina bifida
  • Chronically inflamed joints
  • Under plaster casts
  • Carrying weights over shoulder

52
Causes of hypertrichosis
  • Generalized
  • Anorexia nervosa, starving, malnutrition
  • Drug induced- minoxidil, diazoxide, ciclosporin
  • anabolic steroids.
  • porphyrias
  • Fetal alcohol syndrome
  • Fetal phenytoin syndrome
  • Hypertrichosis lanuginosa(congenital or acpuired)
  • General systemic illness (such as advanced HIV
    infection)
  • Hypothyroidism or other endocrine disorders

53
Hirsutism
  • Cause
  • Increased level of androgens or an
    oversensitivity of hair follicles to androgens
  • Racial or familial trait (Mediterranean,
    Caucasians and Asians)
  • Idiopathic hirsutism
  • Hormonal
  • Polycystic Ovarian Syndrome
  • Cushing's disease
  • Tumors in the ovaries or adrenal gland
  • Congenital adrenal hyperplasia
  • postmenopausal women
  • Itragenic
  • Drugs- androgens or progesterones, anabolic
    steroids.

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55
Presentation
  • An excessive growth of hair in
  • Beard area and side burn
  • Chest
  • Shoulder-tips
  • Around the nipples
  • Abdomen
  • Male pattern of pubic hair
  • Androgenetic alopecia
  • Signs of virilization
  • Temporal hair recession
  • Acne
  • Deep voice, increased size of Adam's apple
  • Oily perspiration
  • Breast atrophy
  • Muscle hypertrophy
  • Loss of female body contour
  • Clitoral enlargement

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Investigations
  • Significant hormonal abnormalities are not
    usually found in patients with a normal menstrual
    cycle.
  • Investigations are needed if
  • Hirsutism occurs in childhood
  • There are features of virilization
  • Hirsutism is of sudden or recent onset
  • There is menstrual irregularity or cessation

59
The tests sent are
  • Total and free testosterone
  • Sex hormone binding globulin
  • Free androgen index
  • Dihydroxyepiandrosterone sulfate
  • Androstenedione (drawn after 10 a.m.)
  • If there is also menstrual disorder, additional
    tests may be requested.
  • Luteinizing hormone (LH) and follicle stimulating
    hormone (FSH)
  • Oestradiol, 17-hydroxy progesterone
  • Prolactin
  • Tests may be requested to evaluate other related
    aspects of health, for example
  • Thyroid function
  • Cortisol or overnight dexamethasone test
  • Glucose
  • Lipids (cholesterol and triglyceride)
  • Pelvic ultrasounds

60
Treatment
  • Treat underlying disorder
  • Home remedies for minor hirsutism include
    commercial, waxing or shaving, or making its
    appearance less obvious by bleaching
  • Plucking should be avoided as it can stimulate
    hair roots into Anagen.
  • The abnormally active follicles can be destroyed
    by electrolysis.
  • If numerous, by laser
  • Topical therapy with eflornithine, an inhibitor
    of ornithine decarboxylase, can slow regrowth.

61
  • Oral antiandrogens
  • Oral contraceptive pills with oestrogen and
    cyproterone- antiandrogenic activity
  • Cyproterone acetate 50-200 mg for 10 days each
    cycle
  • Spironolactone 50-200 mg daily can slowly reduce
    excessive hair growth-long term.
  • Pregnancy must be avoided during such treatment
    as it carries the risk of feminizing a male
    fetus.
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