DISORDER OF SKIN DISORDER OF SKIN APPENDAGESAPPENDAGES

TOPICS INCLUDEDTOPICS INCLUDEDAcne vulgarisRosaceaMiliariaExcessive hair lossExcessive hair growth

DISORDER OF SENACEOUS GLANDS

Acne vulgaris

Sebaceous glandsSebaceous glandsDevelop 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)

Sebum is discharged into the upper part of the hair follicle.

It lubricates and waterproofs the skin, and protects it from drying; It is also mildly bactericidal and

fungistatic.

ACTIVITY 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.

AcneAcne

Acne is a disorder of the pilosebaceous apparatus predominantly affecting the peripubertal popln andcharacterized by comedones, papules, pustules, cysts and scars.

Factors causing acne.Factors causing acne.

PrevalencePrevalence

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.

Causes of Causes of Acne vulgarisAcne vulgaris

Many factors combine to cause acne characterized by chronic inflammation around pilosebaceous follicles

SebumSebum

Sebum excretion is elevated.

Hormonal changesHormonal changes

Androgens (from the testes, ovaries,adrenals and sebaceous glands themselves) are the main stimulants of sebum excretion,

In most of the cases the level of the androgens are within normal limit but there is enhanced end organ sensitivity (incred.activity of enzyme 5-alpha reductase)

Other hormones (e.g. thyroid hormones and growth hormone) have minor effects too.

Poral occlusionPoral occlusion

Occluded by keratinous plug induced by:Both genetic and environmental factors

(e.g. some cosmetics) Reduced levels of linoleic acid in

sebaceous gland secetions of acne patient

Results in vicious cycle of retentin of sebum to growth of microbs. Distention of follicle eventually ruptures releasing pro-inflammatory chemicals into dermis stimulating intense inflammation.The ductal epithelium also produces cytokines and an inflammatory cascade is triggered.

Bacterial Bacterial Propionibacterium acnesPropionibacterium acnes

Acts as a source of antigenic stimulation,triggering a type IV inflammatory response.

Produce extracellular enzymes which attract inflammatoy cells.

Factors modifying AcneFactors modifying AcneGenetic predisposition(mode of

inheritence not clear)The condition is familial mostly with

severe cystic acne Identical twinsCosmeticsMenstrual cyclePsychological factors- anger, anxiety

PresentationPresentationPolymorphic eruption:

papules,pustule,comedones,nodules and cysts

Lesion heals with depressed or hypertrophic scarring and

Post-inflammatory hyperpigmentation can follow.

Lesions are confined to the face, shoulders, upper chest and back.

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.

Associations :Most have a background of greasy skin(seborrhea) with

patulous follicular openings(pores)

Acne associated with virilization

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

Variants of acneVariants of acneInfantile acne may follow

transplacental stimulation of a child’s sebaceous glands by maternal androgens.

May present at birth or may last for upto 3yrs

Its morphology is like that of common acne and it may be the forerunner of severe acne in adolescence.

Mechanical. Excessive scrubbing,

picking, or the rubbing of chin can rupture occluded follicles.

Papulopustular lesions in an odd distribution.The patient played the violin (‘fiddler’s neck’)

Drug-inducedDrug-induced Lesions are monomorphic and esp.

over back ,face may be involved

Suspicion should be raised when acne, dominated by papulopustules rather than comedones appear suddenly in a nonteenager

And coincides with the prescription of a drug known to cause acneiform lesions

Corticosteroids Androgenic Anabolic steroids Gonadotrophins Oral contraceptives Lithium, iodides, bromides,

antituberculosis and anticonvulsant therapy can all cause an acneiform rash.

Steroid-induced acne in a seriously ill patient.

Acne due to cosmeticsAcne due to cosmetics

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 hypertrophicscars, sometimes joined by keloidal bridges.

Hyperpigmentation is usually transient, it can persist, particularly in those with an already dark skin.

Fulminans Acne fulminansFulminans Acne fulminans

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).

chloracneExogenous 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

ExcoriatedExcoriated

This is most common in young girls.

Obsessional picking otherwise mild acne

Results in excoriations on face while primary lesions not visible

Late onsetLate onset

This too occurs mainly in womenIs limited to the chin. Nodular and cystic lesions are

predominant. It is stubborn and persistent.

TropicalTropical

This occurs mainly on the trunk and maybe conglobate.

Acne after facial massageAcne after facial massageAcne following (3-6 wks later) in

abt 30% of patientsNodules with few comedonesAlong mandibular region

CourseCourse

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.

InvestigationsInvestigations

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

◦ Exclude an androgen-secreting tumour of the adrenals, ovaries or testes

◦ To rule out congenital adrenal hyperplasia

Differential diagnosisDifferential diagnosis Rosacea affects older individuals

Pyogenic folliculitis

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.

TreatmentTreatment General measures 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

Local treatmentLocal treatment1 Regular gentle cleansing with mild soap and

waterBenzoyl peroxide.

◦ This antibacterial agent plus decreases inflammation ◦ applied only at night initially, but can be used twice

daily if this does not cause too much dryness and irritation.

Retinoic Acid(RA)/tretinoin◦ The vitamin A (retinol) analogues (tretinoin,

isotretinoin, adapalene,(recently introducedand less irritent) ,tazarotene)normalize follicular keratinization, and reduce sebum production and reduce inflammation,decrease p.acne

They are especially effective against comedones.Patients should be warned about skin irritation (start with

small amounts) and photosensitivity.

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%Other agentsAzelaic acid :reduce post acne hyperpigmentationAlpha hydroxy acids eg. Glycolic acid

Topical antibioticsTopical antibiotics

Topical clindamycin, erythromycin and sulfacetamide

Cosmetic camouflage- Cover-ups help some patients, especially females, whose scarring is unsightly. They also obscure post-inflammatory pigmentation.

Systemic treatmentSystemic treatmentAntibiotics tetracycline includes:doxycycline and

minocycline mostly used and less frequently erythromycin and azithromycin

Used in mod. to severe acne and in those who are having psy. problem

Tetracycline-1gm,doxycycline-100mg,minocycline-100mg, erythromycin-1gm, azithromycin-250mg daily for long periods of time up to 6 mths or even longer.

It should be taken on an empty stomach, 1 h before meals or 4 h after food

Oral antibiotics should be combined with topical agents because then it is possible to withdraw the antibiotic and maintain in topical therapy.

Side effects:GI disturbanceVaginal candidiasisResistanceGrayish pigmentation in case of

minocyclineTo be avoided in pregnancy.

HormonalHormonalAntiandrogenics only for femalesCyproterone acetate, a combined

antiandrogen–oestrogen treatmentCombined oral contraceptivesSpironolactoneIsotretinoin- for severe intractable acneSevere acne,conglobataRelapsesSide effects:dryness of skin, eye,nose

bleed,initial aggravation of inflammation , myalsia, altered night vision and hair loss, avoided in pregnancy,

Careful monitoring with blood pictures and pregnancy test before and after starting rx

Acne scar treatmentAcne scar treatmentDermabrasion This helps to

smooth out facial scars.Lasers Skin resurfacing with

CO2 and erbium lasers is rapidly replacing dermabrasion and chemical peeling

Dermal fillers Bovine collagen or hyaluronic acid fillers can be injected into depressed scars to improve their appearance.

CryotherapyIntralesional corticosterois

ROSACEA

definitiondefinition

Rosacea is a chronic skin disorder characterized by erythema and telangiectasia and punctuated by acute episodic eruption of papules, pustules and swelling.

Rosacea affects the face of adults, usually women.

Although its peak incidence is in the thirties and forties, it can also be seen in the young or old.

It may coexist with acne.

causecauseRosacea is often seen in those who flush

easily in response to warmth, spicy food, alcohol or embarrassment.

Hereditary component Fair-skinnedPsychological abnormalitieschemicals, high dosages of isotretinoin,

benzoyl peroxide and tretinoin.A pathogenic role for the follicular mite

dermodex folliculorum as well as for microaerophilic gm negetive bacterium. Helicobacter pylori is suspected but has not been confirmed.

sitessites

The cheeks, nose, centre of forehead and chin are most commonly affected

The periorbital and perioral areas are usually spared

Lymphoedema, below the eyes and on the forehead, is seen in few cases

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

Usually symmetricalExacerbations and remissions

typestypes

1. Papulopustular rosacea◦Inflammatory lesions are

predominant◦Some permanent redness with red

papules with some pus filled pustules (typically last 1-4 days); this subtype can be easily confused with acne.

Types..Types..2. Erythematotelangiectatic

rosacea◦Vascular features

predominate◦Permanent redness /

erythema with a tendency to flush and blush easily.

◦Small blood vessels are usually visible near the surface of the skin k/a telangiectases, sometimes associated with burning or itching sensations.

Types…Types…3. Phymatous type

◦This subtype is most commonly associated with rhinophyma, an enlargement of the nose.

◦Symptoms include thickening of skin, irregular surface, nodularities, and enlargement of nose.

◦Phymatous rosacea can also affect chin (gnatophyma), forehead (metophyma), eyelids (blepharophyma), and ears (otophyma).

◦Small blood vessels may be visible near the surface of the skin (telangiectases).

.

typestypes

4. Ocular type◦Red, dry and irritated eyes and

eyelids. Some other symptoms include foreign body sensations, itching and burning

ComplicationsComplications

RhinophymaBlepharitisConjunctivitis Keratitislymphedema

RhinophymaRhinophyma

Hyperplasia of the sebaceous glands and connective tissue of the nose

Common in males

Differential diagnosisDifferential diagnosis

AcneSeborrhoeic eczemaPerioral dermatitis Systemic lupus erythematosusPhotodermatitisMenopausal symptomsSuperior venacaval obstruction

Differentiating rosacea from Differentiating rosacea from acneacneRosacea Acne

Absence of comedones Comedones are present

Affects the central face, no trunk involvement

Diffusely over face, trunk involvement is present

Appears after adolescence Usually teenagers

Erythema and telangiectases Telangiectases are not seen

TreatmentTreatment

Topical agentsTopical metronidazole (0.75%

metronidazole gel)Retinoic acidsCorticosteroids not to be usedSystemic therapy:Antibiotics- tetracyclines-start with 1

gm a day reduce dose to 250mg daily over a period of 2-3 ,months ,as the lesions respond

Erythromycin second choiceMetronidazole Isotretinoin 1mg/kg body weight daily

for 3-6mths

Various techniques can be used to improve the appearance of disfiguring rhinophymas ◦Surgical excision◦Cryotherapy◦Electrocautery ◦Argon or CO2 laser ablation.