Simple notes of acne

definition....
it's a disorder of pilosebaceous follicles.
Types of acne....
1-acne vulgaris..this is the typical type
2-juvenile acne
3-occupational acne
4-drug acne
5-cosmetic acne

6-acne fulmines

Pathogenesis...
1-androgens[quantitively&qualitatively normal]stimulate sebaceous glands to produce large amounts of sebum .
2-corynebacterium acne cotains lipase enzyme that acts on lipids of sebum to form free fatty acids , which acts as chemotactic factor for neutrophils.
3-both increase in sebum &free fatty acids which cause sterile inflammation of pilosebaceous gland leading to hyperproliferation of upper portion of sebaceous duct & hyperkeratinization of the lining of the follicle resultingin pulgging.
4-the enlarged follicular lumen containing inspassted keratin & lipid debris resulting in white heads or white comedones.
5-if the folicle has open a portal of entry to the skin the plugg will protrude & the tyrosine contained in the keratin will be oxidized to melanin in the follicle orifice [black heads=black comedons].
6- the distended follicular wall may break dawn, the contents[sebum-lipids-free fatty acids-&keratin]enter the dermis result in forigen body response which make[papules,pastules& nodules]
7-rupture of these lesions+intense inflammation cause post inflammatory hyperpigmentation & scarring.

Causes of acne....
1- body androgens[especially in females because of androgen receptor sensitivity]
2-bacterial infections[propionobacterium acne-staphylococcus epidermis-microsporum ovale]
3-physiological factors[stress- humidity-menstrual cycle].

Clinical description to the acne lesion....
multiple maculopapular rash over the [chin,face,forehead& upper back] with multiple black or white comedones with or without scar or post inflammatory hyperpigmentation spots of a previos healed lesions with greasy skin.



Diffrential diagnosis....
Roscea: looks like acne but it occur in elderly with no comedones ,papules or pastules only associated erythema.

What is the date in which the acne excpected to end..?
most of the cases resolve at age 23-25years but about 5% of cases in females & 1% of cases in males persists up to 25-40years.

What is the 1ry acne..?
it's the non inflammatory acne in which are known as comedones, they take 1-2 weeks to heal.
What is the 2ry acne..?
it's the inflammotory acne which may occur on top of non inflammatory comedones or start DE novo , they present as:
-superficial:papules or pastules[take 2-4 weeks to heal]
-deep: deep pastules,nodules or even cysts[take months to heal].


General treatment:
a-topical treatment---
1)Benzoyal peroxide;it's acomedolytic agent.
2)Retinoic acid;it' a vitamine A derivatives , used as an alternative to benzoyl peroxide so also has a comedolytic affect.
3)topical antiseptics;it's a washes like chlorhexidine but have a little value.
4)topical antibiotics;tetracycline,erythromycin, fucidine & clindamycin.
b-systemic therapies
1)antibiotics;
*must be fat soluble to be effective.
*antibiotics reduce bacterial counts.
*the most effective for acne are
tetracyclines and erythromycin .
*most tetracycline should be taken on an
empty stomach.
*contraindication of tetracyclines are age
under 12,in pregnancy or laction.
2)cyproterone acetate;it's effective anti androgen and can only be given to women.and must be combined with oestrogen to prevent menorrhagia and to ensure contraceptive cover(it will feminize male fetus).
3)retinoic acid
4)steriods;used in cases of sever acne.
5)sugical intervention.


Management of acne patient:
mild acne;
*this is an acne in which only comedones are present only restricted to the face.
*topical treatment alone may control mild acne begining with [benzoyl peroide+retionic acid] with or without aniseptics or topical antibiotics.

Moderate acne;
*this is an acne in which more papulopustular lesions are present on the face or over a wider area .
*1st line treatment of moderate acne should combine topical benzoyl peroxide with tetracycline or erythromycin .
*this treatment taken in a dose of 500mg twice dialy for at least 3 to 6 months before consider any failure.

Sever acne;
1-girls may be treated with cyproterone acetate combined with an oestrogen for a period of at least 6 months.
2-men require retionic acid for at least 4 months.
3- intralesional steriods rarely used in suppressing acute inflammatory lesions.