Sebum produced by sebaceous glands lubricates and protects the skin. Acne is a disorder of the pilosebaceous unit characterized by comedones, papules and pustules. It results from increased sebum production, pore occlusion, bacterial infection with Propionibacterium acnes, and inflammation. Treatment involves addressing these pathological factors with topical and oral medications like benzoyl peroxide, retinoids, antibiotics and isotretinoin. Rosacea is a chronic facial rash distinct from acne, characterized by flushing, erythema and papules.

2.  holocrine secretion of sebum
Functions of sebum
1. lubricates and waterproofs the skin, and protects it
from drying
2. mildly bactericidal and fungistatic.
Free sebaceous glands may be found in the eyelid
(meibomian glands), mucous membranes (Fordyce
spots), nipple, perianal region and genitalia.

3.  especially dihydrotestosterone, stimulate sebaceous
gland activity.
 Human sebaceous glands contain 5a-reductase, 3a-
and 17a-hydroxysteroid dehydrogenase, which
convert weaker androgens to dihydrotestosterone,
which in turn binds to specific receptors in
sebaceous glands, increasing sebum secretion.
 The sebaceous glands react to maternal androgens
for a short time after birth

4.  disorder of the pilosebaceous apparatus
characterized by comedones, papules, pustules,
cysts and scars.
 all teenagers have some acne (acne vulgaris)
 affects the sexes equally
 ages of 12 and 14 years, tending to be earlier in
females.

5. Pathological factors

6. Sebum
 Sebum excretion is increased. However, this alone need not cause acne
Hormonal
 Androgens (from the testes, ovaries, adrenals and sebaceous glands themselves) are
the main stimulants of sebum excretion,
Poral occlusion
 Both genetic and environmental factors (e.g. some cosmetics) cause the epithelium to
overgrow the follicular surface.
 Follicles then retain sebum that has an increased concentration of bacteria and free
fatty acids
 Rupture of these follicles is associated with intense inflammation and tissue damage
Bacterial Propionibacterium acnes
 normal skin commensal, plays a pathogenic part
Genetic
 The condition is familial in about half of those with acne

7. 1. Infantile acne
 follow transplacental stimulation of a child’s sebaceous
glands by maternal androgens.
2. Mechanical
 Excessive scrubbing, picking, or the rubbing of chin
straps or a fiddle

9. 3. Acne associated with virilization
4. Acne accompanying the polycystic ovarian
Syndrome
5. Drug-induced
 Corticosteroids, androgenic and anabolic, steroids,
gonadotrophins, oral contraceptives, lithium, iodides,
bromides, antituberculosis and anticonvulsant therapy
can all cause an acneiform rash.
6. Tropical, Heat and humidity
7. Acne due to cosmetics

10.  Mostly in face, shoulders, upper chest and back.
 Seborrhoea is often present
 Open comedones (blackheads) because of the plugging
by keratin and sebum of the pilosebaceous orifice
 Closed comedones (whiteheads), caused by overgrowth
of the follicle openings by surrounding epithelium
 Inflammatory papules, nodules and cysts
 Depressed or hypertrophic scarring
 post-inflammatory hyperpigmentation
 Psychological depression is common

13. Acne Conglobate
 is severe form of acne
 abscesses or cysts with intercommunicating sinuses
that contain thick serosanguinous fluid or pus
 On resolution, it leaves deeply pitted or hypertrophic
scars, sometimes joined by keloidal bridges
Infantile Acne
 present at or appears soon after birth and may last up
to 3 years

15. Fulminans Acne
 conglobate acne is accompanied by fever, joint pains and a
high erythrocyte sedimentation rate (ESR)
 Excoriated Acne
Late onset Acne
 Women, limited to the chin, Nodular and cystic lesions
predominate
 It is stubborn
Tropical Acne
Drug-induced Acne
Hormonal induced Acne

20.  Acne vulgaris clears by the age of 23–25 years in
90% of patients
 5% of women and 1% of men still need treatment in
their thirties or even forties.

21.  No need usually
 Cultures are occasionally needed to exclude a
pyogenic infection, an anaerobic infection or Gram-
negative folliculitis
 exclude an androgen-secreting tumour of the
adrenals, ovaries or testes, and to rule out
congenital adrenal hyperplasia caused by 21-
hydroxylase deficiency, polycystic ovarian syndrome

22.  Rosacea
 Pyogenic folliculitis
 Hidradenitis suppurativa
 Pseudofolliculitis barbae

23. 1. General measures
 regular encouragement worthwhile
 underlying cause should be removed or treated.
2. Local treatment
3. Systemic treatment
 Antibiotics
 Hormonal

24.  Regular gentle cleansing with soap and water to
remove surface sebum.
Benzoyl peroxide
 Is an antibacterial agent
 most effective for inflammatory lesions not affected
by propionibacterial antibiotic resistance
 start with a 2.5% or 5% preparation, moving up to 10%
if necessary.

25. Retinoids.
 normalize follicular keratinization
 down-regulate TLR2 expression
 reduce sebum production
 effective against comedones
Side effects
 skin irritation and photosensitivity
 applied overnight on alternate nights
 stop temporarily if irritation
 worth increasing the strength of tretinoin after 6 weeks if it has been
well tolerated
Contraindication
 Concomitant eczema and Pregnant women

26. Azelaic acid
 bactericidal for P. acne
 Have an anti-inflammatory effect
 inhibits the formation of comedones
 It should be applied twice daily, but not used for more than 6
months at a time
Topical antibiotics
 topical clindamycin, erythromycin and sulfacetamide
 antibacterial resistance of P. acnes is a most erythromycin-
resistant strains being cross-resistant to clindamycin
 Combining antibiotics with benzoyl peroxide reduces P. acnes
numbers and the likelihood of resistant strains Emerging
 The addition of zinc acetate complex to erythromycin enhances
the antibiotic’s anti-inflammatory effect
Cosmetic camouflage

28. Oxytetracycline and tetracycline.
 starting dosage for an adult is 500 mg twice daily, but up to
1.5 g/day may be needed in resistant cases.
 Used not less than 3 months and may be needed for 1–2
years, or even longer.
 It should be taken on an empty stomach, 1 h before meals
or 4 h after food, as the absorption of these tetracyclines is
decreased by milk, antacids and calcium, iron and
magnesium salts.
 maintenance dosage being 250–500 mg/ day.
 serious side-effects are rare, although candidal
vulvovaginitis may force a change to a narrower spectrum
antibiotic such as erythromycin.

29. Minocycline
 50 mg twice daily or 100 mg once or twice daily is now preferred by
many dermatologists
 Absorption is not significantly affected by food or drink.
 Minocycline is much more lipophilic than oxytetracycline and so
probably concentrates better in the sebaceous glands.
 can cause abnormalities of liver function and a lupus-like syndrome.
 Rarely, the long-term administration of minocycline causes a greyish
pigmentation, like a bruise, especially on the faces of those with actinic
damage and over the shins.
Doxycycline
 100 mg once or twice daily is a cheaper alternative to minocycline
 more frequently associated with phototoxic skin reactions.
Contraindications
 Tetracyclines should not be taken in pregnancy or by children under 12
years as they are deposited in growing bone and developing teeth,
causing stained teeth and dental hypoplasia.

30. Erythromycin
 Is the next antibiotic of choice
 is preferable to tetracyclines in women who might become
pregnant.
 Its major drawbacks are nausea and the widespread
development of resistant Proprionibacteria, which leads to
therapeutic failure.
Trimethoprim
 with or without sulfamethoxazole
 by some as a third-line antibiotic for acne, when a
tetracycline and erythromycin have not helped. White
blood cell counts should be monitored.
 Ampicillin is another alternative.

31. Isotretinoin
 is an oral retinoid
 inhibits sebum excretion, the growth of P. acnes and
acute inflammatory processes.
 reserved for severe nodulocystic acne, unresponsive to
the measures outlined above.
 It is routinely given for 4–6 months only, in a dosage of
0.5–1 mg/kg body weight/day
 A full blood count, liver function tests and fasting lipid
levels should be checked before the start of the course,
and then 1 and 4 months after starting the drug.

32.  Isotretinoin is highly teratogenic
 Effective contraception must be taken for 1 month
before, throughout and for 1 month after treatment.
 Tests for pregnancy are carried out monthly while the
drug is being taken only a single month’s supply of the
drug should be prescribed at a time
 Treatment should start on day 3 of the patient’s next
menstrual cycle following a negative pregnancy test.

33. Other side-effects of isotretinoin include:
1. Depression rarely lead to suicide
2. a dry skin, dry and inflamed lips and eyes,
nosebleeds
3. facial erythema, muscle aches
4. hyperlipidaemia and hair loss
 these are reversible and often tolerable, especially if
the acne is doing well.
5. Rarer and potentially more serious side-effects
include changes in night-time vision and hearing loss

35.  Rosacea affects the face of adults, usually women.
 peak incidence is in the thirties and forties, it can also
be seen in the young or old.
 It may coexist with acne but is distinct from it.

36.  The cause is still unknown.
 Rosacea is often seen in those who flush easily in
response to warmth, spicy food, alcohol or
embarrassment. No pharmacological defect has been
found that explains these flushing attacks.
 Psychological abnormalities, including neuroticism
and depression, are more often secondary to the skin
condition than their cause.
 Sebum excretion rate and skin microbiology are
normal

37.  The cheeks, nose, centre of forehead and chin are most
commonly affected
 the periorbital and perioral areas are spared
 Intermittent flushing is followed by a fixed erythema
and telangiectases.
 Discrete domed inflamed papules, papulopustules
and, rarely, plaques or nodules develop.
 no comedones or seborrhoea.
 It is usually symmetrical.
 Its course is prolonged, with exacerbations and
remissions.

40.  Blepharitis
 conjunctivitis
 Keratitis
 Rhinophyma
 Lymphoedema, below the eyes and on the forehead

42. Acne
 Rosacea differs from it by:
1. its background of erythema and telangiectases
2. absence of comedones
3. distribution of the lesions is central face but not the
trunk.
4. usually appears after adolescence.

43. Sun-damaged skin with or without acne cosmetica
causes most diagnostic difficulty
 Remember, rosacea affects primarily the central, less
mobile parts of the face, whereas sun damage and acne
cosmetica are more generalized over the face
The flushing of rosacea can be confused with:
1. menopausal symptoms
2. carcinoid syndrome
3. Superior vena caval obstruction

44.  Seborrhoeic eczema
 perioral dermatitis
 systemic lupus erythematosus
 photodermatitis
they do not show the papulopustules of rosacea

45.  Rosacea and topical steroids go badly together
Papulopustular rosacea
Systemic
 tetracyclines as for acne are the traditional treatment and are
usually effective.
 Erythromycin is the antibiotic of second choice.
 Courses should last for at least 10 weeks and, after gaining
control with 500–1000 mg/day, the dosage can be cut to 250
mg/day
 The condition recurs in about half of the patients within 2 years,
but repeated antibiotic courses, rather than prolonged
maintenance ones, are generally recommended
 Rarely, systemic metronidazole or isotretinoin is needed for
stubborn rosacea

46. Topical
 Topical 0.75% metronidazole gel, 15% azelaic acid and
sulfacetamide/sulphur lotions applied once or twice
daily
 are nearly as effective as oral tetracycline and often
prolong remission
 Sunscreens help if sun exposure is an aggravating
factor
 changes in diet or drinking habits are seldom of value