DISORDER OF SKIN APPENDAGES. TOPICS INCLUDED. Acne vulgaris Rosacea Miliaria Excessive hair loss Excessive hair growth. DISORDER OF SENACEOUS GLANDS Acne vulgaris. Sebaceous glands. Develop embryologically from hair germs, but a few free glands arise from the epidermis.
Develop embryologically from hair germs, but a few free glands arise from the epidermis.
The glands themselves are multilobed
Contain cells full of lipid(sebum), which are secreted (holocrine secretion-when whole cell is secreted into the lumen)
It lubricates and waterproofs the
skin, and protects it from drying;
It is also mildly bactericidal and fungistatic.
Androgenic hormones, especially dihydrotestosterone, stimulate sebaceous gland activity.
Human sebaceous glands contain 5α-reductase, 3α- and 17α- hydroxysteroid dehydrogenase
Convert weaker androgens to dihydrotestosterone, which in turn binds to specific receptors in sebaceous glands, increasing sebum secretion.
So , not the levels of circulating androgens but an enhanced target organ sensitivity which is important.
Acne is a disorder of the pilosebaceous apparatus predominantly affecting the peripubertal popln andcharacterized by comedones, papules, pustules, cysts and scars.
Nearly all teenagers have some acne (acne vulgaris).
It affects the sexes equally, starting usually between the ages of 12 and 14 years, tending to be earlier in females.
The peak age for severity in females is 16–17 and in males 17–19 years.
Variants of acne are much less common.
Many factors combine to cause acne characterized by chronic inflammation around pilosebaceous follicles
Sebum excretion is elevated.
Occluded by keratinous plug induced by:
Acts as a source of antigenic stimulation,triggering a type IV inflammatory response.
Produce extracellular enzymes which attract inflammatoy cells.
Genetic predisposition(mode of inheritence not clear)
The condition is familial mostly with severe cystic acne
Psychological factors- anger, anxiety
papules,pustule,comedones,nodules and cysts
Lesion heals with depressed or hypertrophic scarring and
Post-inflammatory hyperpigmentation can
Open comedones (blackheads), because of the plugging by keratin and sebum of the pilosebaceous orifice on the skin surface, or
Closed comedones (whiteheads), caused by plugging below the skin surface.
Most have a background of greasy skin(seborrhea) with patulous follicular openings(pores)
May be caused by an androgen-secreting tumour of the adrenals, ovaries or testes or, rarely,
congenital adrenal hyperplasia
Acne accompanying the polycystic ovarian syndrome is caused by modestly raised circulating androgen levels
The patient played the violin (‘fiddler’s neck’)
Excessive scrubbing, picking, or the rubbing of chin can rupture occluded follicles.
Steroid-induced acne in a seriously ill patient.
Cosmetics esp. oil based or other topical preparations may induce comedone formation or precipitate inflammation around hair follicles.
Conglobates (gathered into balls) is the name given to a severe form of acne with all of the above features as well as 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.
Hyperpigmentation is usually transient, it can persist, particularly in those with an already dark skin.
It is a rare variant in which conglobate acne with ulcerated and crusted lesion and is accompanied by
Fever, arthralgia,myalsia and a high erythrocyte sedimentation rate (ESR).
Exogenous Tars, chlorinated hydrocarbons, oils and oily cosmetics can cause or exacerbate acne.
Suspicion should be raised if the distribution is odd(forearm, legs)or unusal age(mid age male) or if comedones predominate
This is most common in young girls.
Obsessional picking otherwise mild acne
Results in excoriations on face while primary lesions not visible
This too occurs mainly in women
Is limited to the chin.
Nodular and cystic lesions are predominant.
It is stubborn and persistent.
This occurs mainly on the trunk and may
Acne vulgaris clears by the age of 23–25 years in 90% of patients,
Some (5% of women and 1% of men) still need treatment in their thirties or even forties.
None are usually necessary.
Cultures are occasionally needed to exclude a pyogenic infection, an anaerobic infection or Gram-negative folliculitis.
Any acne, including infantile acne, that is associated with virilization needs investigation to
Rosacea affects older individuals
Hidradenitis suppurativa is associated with acne conglobata, but attacks the axillae and groin.
Pseudofolliculitis barbae, caused by ingrowing hairs, occurs on the necks of men with curly facial hair and clears up if shaving is stopped.
Acne frequently has marked psychological effects.
Even those with mild acne need sympathy, optimistic approach is essential, and regular encouragement is worthwhile.
Local hygiene, diet, stress
The weakest preparation should be used first, and applied overnight on alternate nights.
Sometimes, after a week or two, it will have to be stopped temporarily because of irritation.
The combination of benzoyl peroxide in the morning and tretinoin at night has many advocates.
Isotretinoin 0.05%, 0.025%, 0.1%
Azelaic acid :reduce post acne hyperpigmentation
Alpha hydroxy acids eg. Glycolic acid
Topical clindamycin, erythromycin and sulfacetamide
Cosmetic camouflage- Cover-ups help some patients, especially females, whose scarring is unsightly. They also obscure post-inflammatory pigmentation.
Oral antibiotics should be combined with topical agents because then it is possible to withdraw the antibiotic and maintain in topical therapy.
Rosacea is a chronic skin disorder characterized by erythema and telangiectasia and punctuated by acute episodic eruption of papules, pustules and swelling.
adults, usually women.
forehead and chin are most commonly affected
Exacerbations and remissions
1. Papulopustular rosacea
2. Erythematotelangiectatic rosacea
3. Phymatous type
4. Ocular type
Hyperplasia of the sebaceous glands and connective tissue of the nose
Common in males
Systemic lupus erythematosus
Superior venacaval obstruction
Various techniques can be used to improve the appearance of disfiguring rhinophymas