3. Classification of hairs:Classification of hairs:
1.1. Lanugo hairsLanugo hairs.. Fine long hairs covering the fetus, but shedFine long hairs covering the fetus, but shed
about 1 month before birth.about 1 month before birth.
2.2.Vellus hairsVellus hairs.. Fine short unmedullated hairs covering muchFine short unmedullated hairs covering much
of the body surface. They replace the lanugo hairs justof the body surface. They replace the lanugo hairs justbeforebefore
birth.birth.
3.3.Terminal hairsTerminal hairs.. Long coarse medullated hairs seen,Long coarse medullated hairs seen,
for example, in the scalp or pubic regions. Their growthfor example, in the scalp or pubic regions. Their growth
is often influenced by circulating androgen levelsis often influenced by circulating androgen levels..
4. The hair cycleThe hair cycle
There are three phases of follicular activity:There are three phases of follicular activity:
1.1. AnagenAnagen.. The active phase of hair production.The active phase of hair production.
2.2. CatagenCatagen.. A short phase of conversion from activeA short phase of conversion from active
growth to the resting phase. Growth stops, and thegrowth to the resting phase. Growth stops, and the
end of the hair becomes club-shaped.end of the hair becomes club-shaped.
3.3. TelogenTelogen.. A resting phase at the end of which theA resting phase at the end of which the
club hair is shedclub hair is shed..
5. The scalp contain an average of 100 000 hairs,The scalp contain an average of 100 000 hairs,
anagen lasts for up to 5 years,anagen lasts for up to 5 years,
catagen for about 2 weeks,catagen for about 2 weeks,
and telogen for about 3 months.and telogen for about 3 months.
As many as 100 hairs may be shed from theAs many as 100 hairs may be shed from the
normal scalp every day as a normal consequencenormal scalp every day as a normal consequence
of cycling.of cycling.
On the scalp, about 85% are normally in anagenOn the scalp, about 85% are normally in anagen
and 15% in the telogen phaseand 15% in the telogen phase..
11. Localized alopecia:Localized alopecia:
1. alopecia areata:1. alopecia areata:
Affects about 2% of the population.Affects about 2% of the population.
Cause:Cause:
-immunological; because of an association with-immunological; because of an association with
thyroid disease, atopy and vitiligo.thyroid disease, atopy and vitiligo.
Histologically, T lymphocytes cluster like aHistologically, T lymphocytes cluster like a
swarm of bees around affected follicles.swarm of bees around affected follicles.
-genetic; increased occurrence in the first degree-genetic; increased occurrence in the first degree
relatives of affected subjects and twinrelatives of affected subjects and twin
concordance.concordance.
-trigger factors as such as stress-trigger factors as such as stress..
12. Presentation:Presentation:
A typical patch is uninflammed, with no scalingA typical patch is uninflammed, with no scaling
but with easily seen empty hair follicles.but with easily seen empty hair follicles.
Pathognomonic 'exclamation mark' hairs may bePathognomonic 'exclamation mark' hairs may be
seen around the edge of the enlarging areas.seen around the edge of the enlarging areas.
They are broken off about 4 mm from the scalp,They are broken off about 4 mm from the scalp,
and are narrowed and less pigmentedand are narrowed and less pigmented
proximallyproximally..
13. Patches are most common in the scalp and beardPatches are most common in the scalp and beard
area but other areas, especially the eyelashes andarea but other areas, especially the eyelashes and
eyebrows, can be affected.eyebrows, can be affected.
An uncommon diffuse pattern is recognized.An uncommon diffuse pattern is recognized.
Up to 50% of patients show fine pitting orUp to 50% of patients show fine pitting or
wrinkling of the nailswrinkling of the nails..
14.
15.
16.
17.
18. Course:Course:
The outcome is unpredictable.The outcome is unpredictable.
In a first attack, regrowth is usual within a fewIn a first attack, regrowth is usual within a few
months new hairs appear in the centre of patchesmonths new hairs appear in the centre of patches
as fine pale down, and gradually regain theiras fine pale down, and gradually regain their
normal thickness and color, although the newnormal thickness and color, although the new
hair may remain white in older patients.hair may remain white in older patients.
Subsequent episodes tend to be more extensiveSubsequent episodes tend to be more extensive
and regrowth is slower.and regrowth is slower.
A few patients loss all the hair from their headA few patients loss all the hair from their head
(alopecia totalis), or from the whole skin surface(alopecia totalis), or from the whole skin surface
(alopecia universalis(alopecia universalis).).
19. Poor prognostic factors;Poor prognostic factors;
1. onset before puberty.1. onset before puberty.
2. association with atopy or down's disease.2. association with atopy or down's disease.
3. widespread alopecia.3. widespread alopecia.
4. involvement of the scalp margin (ophiasiform4. involvement of the scalp margin (ophiasiform
typetype).).
20. Differential diagnosis:Differential diagnosis:
-patches are non-scaly in contrast to ringworm.-patches are non-scaly in contrast to ringworm.
-non-inflamed in contrast to lupus erythematosus-non-inflamed in contrast to lupus erythematosus
or lichen planus.or lichen planus.
-in hair puling habit of children, and in traction-in hair puling habit of children, and in traction
alopecia, broken hairs may be seen, but truealopecia, broken hairs may be seen, but true
exclamation-mark hairs are absentexclamation-mark hairs are absent..
21. Treatment:Treatment:
-a patient with first or minor attacks can be-a patient with first or minor attacks can be
reassured, tranquillizers may be helpful at thereassured, tranquillizers may be helpful at the
start.start.
-intralesional triamcinolone acetonide (10mg/ml)-intralesional triamcinolone acetonide (10mg/ml)
leads to localized tufts of regrowth.leads to localized tufts of regrowth.
-spirit-based steroid lotion.-spirit-based steroid lotion.
-mild irritants such as 0.1-0.25% dithranol.-mild irritants such as 0.1-0.25% dithranol.
-UV radiation and PUVA.-UV radiation and PUVA.
-contact sensitizers (diphencyprone).-contact sensitizers (diphencyprone).
-topical immunosuppressive agents as-topical immunosuppressive agents as
tacrolimus.tacrolimus.
-systemic steroids better to be avoided-systemic steroids better to be avoided..
22. Androgenetic alopecia (male pattern baldness):Androgenetic alopecia (male pattern baldness):
Cause:Cause:
Familial, but exact mode of inheritance is not yet beenFamilial, but exact mode of inheritance is not yet been
clarified.clarified.
The idea of a single autosomal dominant gene, withThe idea of a single autosomal dominant gene, with
reduced penetrance in women, now seems likely thanreduced penetrance in women, now seems likely than
polygenic type of inheritance.polygenic type of inheritance.
Male-pattern baldness is androgen-dependance; inMale-pattern baldness is androgen-dependance; in
females androgenetic alopecia with normal limits offemales androgenetic alopecia with normal limits of
circulating levels of androgen, is seen only in those whocirculating levels of androgen, is seen only in those who
are strongly predisposed geneticallyare strongly predisposed genetically..
23. Presentation:Presentation:
The common pattern in men is the loss of hair first fromThe common pattern in men is the loss of hair first from
the temples, and then from the crown.the temples, and then from the crown.
In women the hair loss may much more diffuse,In women the hair loss may much more diffuse,
particularly from the crown.particularly from the crown.
In bald areas, terminal hairs are replaced by finer vellusIn bald areas, terminal hairs are replaced by finer vellus
hairs.hairs.
Investigations:Investigations:
none are needed, in women virilization may have to benone are needed, in women virilization may have to be
excludedexcluded..
24.
25.
26. Treatment:Treatment:
1. Topical minoxidil; may slow early hair loss and1. Topical minoxidil; may slow early hair loss and
even stimulate new growth of hair. Small and recentlyeven stimulate new growth of hair. Small and recently
acquired patches respond best. When treatment stops,acquired patches respond best. When treatment stops,
the new hairs fall out after about three months.the new hairs fall out after about three months.
2. Fenasteride; inhibitor of human type II 5α-2. Fenasteride; inhibitor of human type II 5α-
reductase, reduces serum and scalp skin levels ofreductase, reduces serum and scalp skin levels of
dihydrotestosterone in balding men at the dosage of 1dihydrotestosterone in balding men at the dosage of 1
mg/day. The beneficial effect slowly reverses oncemg/day. The beneficial effect slowly reverses once
treatment has stopped. The treatment is not indicated intreatment has stopped. The treatment is not indicated in
women and childrenwomen and children..
27. Traction alopecia:Traction alopecia:
Cause:Cause:
Hairs can be pulled out by several proceduresHairs can be pulled out by several procedures
intended to beutify, including hot-combing tointended to beutify, including hot-combing to
straighten kinky hair, tight hairstyles such asstraighten kinky hair, tight hairstyles such as
pony tailor 'corn rows' and using hair rollers toopony tailor 'corn rows' and using hair rollers too
often or too tightlyoften or too tightly..
28. Presentation:Presentation:
Usually seen in girls and young women.Usually seen in girls and young women.
The pattern of hair loss is determined by theThe pattern of hair loss is determined by the
cosmetic procedure in use, hair been lost wherecosmetic procedure in use, hair been lost where
there is maximal tug.there is maximal tug.
The term marginal alopecia is applied to oneThe term marginal alopecia is applied to one
common pattern in which hair loss is mainlycommon pattern in which hair loss is mainly
around the edge of the scalp-at the sides or at thearound the edge of the scalp-at the sides or at the
front.front.
The bald areas show short broken hairs,The bald areas show short broken hairs,
folliculitis and sometime scarring.folliculitis and sometime scarring.
Treatment:Treatment: avoidance of causative factorsavoidance of causative factors..
29.
30.
31. Trichotillomania:Trichotillomania:
This is the habit of hair pulling, it is usually ofThis is the habit of hair pulling, it is usually of
little consequence, and children who twist andlittle consequence, and children who twist and
pull their hair, often as they are going to sleep,pull their hair, often as they are going to sleep,
seldom have major psychiatric problem. Theseldom have major psychiatric problem. The
habit often goes away if it is ignoredhabit often goes away if it is ignored..
32. However, more sever degrees of hair-pulling areHowever, more sever degrees of hair-pulling are
sometimes seen in disturbed adolescence and insometimes seen in disturbed adolescence and in
those with learning difficulties; then the outlookthose with learning difficulties; then the outlook
for full regrowth is less good, even with formalfor full regrowth is less good, even with formal
psychiatric helppsychiatric help..
33. The bald areas do not show exclamation mark ofThe bald areas do not show exclamation mark of
alopecia areata, or the scaling or inflammation ofalopecia areata, or the scaling or inflammation of
ringworm.ringworm.
The patterns are irregular in outline and hair lossThe patterns are irregular in outline and hair loss
is not complete.is not complete.
Those hairs that remain are bent or broken, andThose hairs that remain are bent or broken, and
of variable lengthof variable length..
34. Patchy hair loss caused by skin disease:Patchy hair loss caused by skin disease:
1. scalp ringworm:1. scalp ringworm:
Inflammation with postulation is a feature ofInflammation with postulation is a feature of
animal ringworm, and the resultant scarring cananimal ringworm, and the resultant scarring can
be sever.be sever.
Human ringworm produces scaling and brokenHuman ringworm produces scaling and broken
hairshairs..
35. 22..Psoriasis:Psoriasis:
The rough removal of adherent scales can alsoThe rough removal of adherent scales can also
remove the hairs, but regrowth is the ruleremove the hairs, but regrowth is the rule..
36. 33..scarring alopecia:scarring alopecia:
Hair follicles may damage in many ways. IfHair follicles may damage in many ways. If
follicular openings can no longer be seen with afollicular openings can no longer be seen with a
lens, regrowth of hair can not beexpected.lens, regrowth of hair can not beexpected.
Causes; sever burn, trauma, carbuncle,Causes; sever burn, trauma, carbuncle,
inflammatory ringworm, discoid lupusinflammatory ringworm, discoid lupus
erythematosus, lichen planus, morphoea, anderythematosus, lichen planus, morphoea, and
pseudopeladepseudopelade..
37.
38. Diffuse hair loss:Diffuse hair loss:
Some causes of diffuse hair loss:Some causes of diffuse hair loss:
1.Telogen effluvium1.Telogen effluvium
2. Endocrine2. Endocrine
-hypopituitarism-hypopituitarism
-hypo- or hyperthyroidism-hypo- or hyperthyroidism
-hypoparathyroidism-hypoparathyroidism
3. Drug-induced3. Drug-induced
-antimitotic agents (anagen effluvium)-antimitotic agents (anagen effluvium)
-anticoagulants-anticoagulants
-vitamin A excess-vitamin A excess
-oral contraceptives-oral contraceptives
4. Androgenetic4. Androgenetic
5. Iron deficiency5. Iron deficiency
6. Severe chronic illness6. Severe chronic illness
7. Malnutrition7. Malnutrition
8. Diffuse type of alopecia areata8. Diffuse type of alopecia areata
39. Telogen effluviumTelogen effluvium
CauseCause
Telogen effluvium can be triggered by anyTelogen effluvium can be triggered by any
severe illness, particularly those with bouts ofsevere illness, particularly those with bouts of
fever or haemorrhage, by childbirth and byfever or haemorrhage, by childbirth and by
severe dieting.severe dieting.
All of these synchronize catagen so that, later on,All of these synchronize catagen so that, later on,
large numbers of hairs are lost at the same timelarge numbers of hairs are lost at the same time..
40. Presentation and course
The diffuse hair fall, 2–3 months after the
provoking illness, can be mild or severe.
In the latter case Beau’s lines may be seen
on the nails.
Regrowth, not always complete, usually
occurs within a few months.
41. Differential diagnosisDifferential diagnosis
This is from other types of diffuse hair loss.This is from other types of diffuse hair loss.
TreatmentTreatment
This condition is unaffected by therapy, butThis condition is unaffected by therapy, but
patients can be reassured that their hair fall willpatients can be reassured that their hair fall will
be temporarybe temporary..
42. Hirsutism and hypertrichosisHirsutism and hypertrichosis
HirsutismHirsutism is the growth of terminal hair in ais the growth of terminal hair in a
female which is distributed in the patternfemale which is distributed in the pattern
normally seen in a male.normally seen in a male.
HypertrichosisHypertrichosis is an excessive growth ofis an excessive growth of
terminal hair that does not follow anterminal hair that does not follow an
androgen-induced patternandrogen-induced pattern..
43. HirsutismHirsutism
CauseCause
*Some degree of hirsutism may be a racial or*Some degree of hirsutism may be a racial or
familial trait, and minor facial hirsutism isfamilial trait, and minor facial hirsutism is
common after the menopause.common after the menopause.
*In addition, some patients without a family*In addition, some patients without a family
background of hirsutism become hirsute in thebackground of hirsutism become hirsute in the
absence of any demonstrable hormonal causeabsence of any demonstrable hormonal cause
(idiopathic hirsutism(idiopathic hirsutism(.(.
45. PresentationPresentation
An excessive growth of hair appears in the beard area,An excessive growth of hair appears in the beard area,
on the chest and shoulder-tips, around the nippleson the chest and shoulder-tips, around the nipples
and in the male pattern of pubic hair. Androgeneticand in the male pattern of pubic hair. Androgenetic
alopecia may complete the picture.alopecia may complete the picture.
CourseCourse
Familial, racial or idiopathic hirsutism tends to startFamilial, racial or idiopathic hirsutism tends to start
at puberty and to worsen with age.at puberty and to worsen with age.
ComplicationsComplications
Virilization causes infertility; psychological disturb-Virilization causes infertility; psychological disturb-
ances are commonances are common..
46.
47.
48. InvestigationsInvestigations
Significant hormonal abnormalities are not usuallySignificant hormonal abnormalities are not usually
found in patients with a normal menstrual cycle.found in patients with a normal menstrual cycle.
Investigations are needed:Investigations are needed:
• if hirsutism occurs in childhood;• if hirsutism occurs in childhood;
• if there are other features of virilization, such as• if there are other features of virilization, such as
clitoromegaly;clitoromegaly;
• if the hirsutism is of sudden or recent onset; or• if the hirsutism is of sudden or recent onset; or
• if there is menstrual irregularity or cessation.• if there is menstrual irregularity or cessation.
The tests used will include measurement of the serumThe tests used will include measurement of the serum
testosterone, sex-hormone-binding globulin, LH,testosterone, sex-hormone-binding globulin, LH,
FSH,dehydroepiandrosterone sulphate, androstenedioneFSH,dehydroepiandrosterone sulphate, androstenedione
and prolactin.and prolactin.
Ovarian ultrasound is useful if polycysticOvarian ultrasound is useful if polycystic
ovaries are suspected.ovaries are suspected.
CT and MRI if tumor suspectedCT and MRI if tumor suspected..
49. Treatment:Treatment:
*Any underlying disorder must be treated .*Any underlying disorder must be treated .
*Home remedies for minor hirsutism include*Home remedies for minor hirsutism include
commercial depilatory creams (often containingcommercial depilatory creams (often containing
a thioglycollate(, waxing or shaving, or makinga thioglycollate(, waxing or shaving, or making
the appearance less obvious by bleaching; nonethe appearance less obvious by bleaching; none
remove the hair permamentl.remove the hair permamentl.
*The abnormally active follicles, if relatively*The abnormally active follicles, if relatively
few, can be destroyed by electrolysis.few, can be destroyed by electrolysis.
*If the hairs are too numerous for this, the excess*If the hairs are too numerous for this, the excess
can be removed by lasercan be removed by laser..
50. **Topical therapy with eflornithine, an inhibitor ofTopical therapy with eflornithine, an inhibitor of
ornithine decarboxylase, can slow regrowthornithine decarboxylase, can slow regrowth..
**Oral antiandrogens (e.g. cyproterone acetate;Oral antiandrogens (e.g. cyproterone acetate;
Dianette; metformine; finasteride( may sometimes beDianette; metformine; finasteride( may sometimes be
helpful, but will be needed long-term. Pregnancy musthelpful, but will be needed long-term. Pregnancy must
be avoided during such treatment as it carries the riskbe avoided during such treatment as it carries the risk
of feminizing a male fetusof feminizing a male fetus..
Spironolactone is used less often nowSpironolactone is used less often now..
51. HypertrichosisHypertrichosis
The localized type is most commonly seen over mela-The localized type is most commonly seen over mela-
nocytic naevi including Becker’s naevi.nocytic naevi including Becker’s naevi.
It can also affect the sacral area as a ‘satyr’s tuft’inIt can also affect the sacral area as a ‘satyr’s tuft’in
some patients with spina bifida.some patients with spina bifida.
Excessive amounts of hair may grow near chronicallyExcessive amounts of hair may grow near chronically
inflamed joints or under plaster casts.inflamed joints or under plaster casts.
Repeated shaving does not bring on hypertrichosisRepeated shaving does not bring on hypertrichosis
although occupational pressure may do so, e.g. fromalthough occupational pressure may do so, e.g. from
carrying weights on the shoulder.carrying weights on the shoulder.
Generalized hypertrichosis is much less commonGeneralized hypertrichosis is much less common..
52. Some causes of generalized hypertrichosisSome causes of generalized hypertrichosis..
-Anorexia nervosa, starvation-Anorexia nervosa, starvation
-Drug-induced (minoxidil, diazoxide, cyclosporin(-Drug-induced (minoxidil, diazoxide, cyclosporin(
-Hepatic cutaneous porphyria-Hepatic cutaneous porphyria
-Fetal alcohol and fetal phenytoin syndromes-Fetal alcohol and fetal phenytoin syndromes
-Hypertrichosis lanuginosa (both congenital type and-Hypertrichosis lanuginosa (both congenital type and
acquired types are very rare the latter signals an internalacquired types are very rare the latter signals an internal
malignancy(malignancy(
-Some rare syndromes, e.g. Cornelia de Lange-Some rare syndromes, e.g. Cornelia de Lange
syndrome (hypertrichosis, microcephaly and mentalsyndrome (hypertrichosis, microcephaly and mental
deficiency( and Hurler’s syndromedeficiency( and Hurler’s syndrome