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Acne Vulgaris
Mohammed Beyan/MD/
Dermatovenereologist
ALERT
Acne Vulgaris
Studies indicate that white patients are more likely to experience moderate to severe acne than black patients
Patients tend themselves as nervous tend to suffer more from acne
The peak of severity in females is 16-17 yrs and in males 17-19 yr
Acne clears by age of 23 – 25 in 90% of patients
Some 5% of women and 1% of men still need treatment in their thirties or even forties
Introduction
Etiology
Many factors combine to cause chronic inflammation of
blocked pilosebaceous follicles
The Pilosebaceous unit consists of cell lined hair follicle containing rudimentary ―بدائي‖ vellus hair (the
fine, non pigmented hairs that cover most of the body) and also consists of sebaceous gland.
The sebaceous gland’s secretions pass up ward
through the duct that carries the hair to the surface
Pilosebaceous density is greatest on the face, upper neck and chest
At puberty, an abnormal cohesion takes placebetween the epithelial cells that cover the unit,this is called keratinization – sebum outflow
is retarded.
Also androgens provoke the sebaceous glandsto become multilobular which results in anincreased sebum output.
Bacteria infect the part and leads toinflammation.
As sebum accumulates behind the keratoticplug, dilation distorts the normal folliculararchitecture, forming a microcomedo (asmall white head), …………………………..it
grows and become closed comedo known aswhite head
The pathophysiology
of acne
Increased and abnormal keratinization at theexit of the pilosebaceous follicle obstructs theflow of sebum, bacteria play a pathogenicrole.Propionibacterium acnes is a normalcommensal, it colonizes the pilosebaceousducts, breaks down the triglycerides, releasingfree fatty acids, produces substanceschemotactic for inflammatory cells andinduces the ductal epithelium to secrete proinflammatory cytokines.
Follicular rupture, which occurs to an inflamed pilosebaceous unit, results in formation of a papule, pustule or cyst (nodule)
In summary there are four main factors responsible for the
pathogenesis of acne: Increased sebum production,ductal hypercornification, bacterial proliferation
and inflammation
Whitehead: A condition of the skin characterized by a small, firm, whitish, closed elevation of the skin. Also known as a closed comedo; is a non inflammatory lesion.
Blackhead: A condition of the skin characterized by a black coloration at the skin surface. Also known as an open comedo; is a non inflammatory lesion.
Progression of acne
Comedo (plural comedones)—A comedo is a sebaceous
follicle plugged with sebum, dead cells from inside the
sebaceous follicle, tiny hairs, and sometimes bacteria
Comedonal acne
Comedonal acne is the earliest clinical expression of acne, is usually non inflammatory
Typically affects the central forehead, chin, nose and paranasal areas.
This form of acne develops in the preteenage or early teenage years as a result of increased sebum production and abnormal desquamation of epithelial cells.
Colonization by P. acnes has not yet occurred, so there usually are no inflammatory lesions. At this stage, therapy should be focused on prevention, minimizing formation of new comedones and the proliferation of P. acnes.
Cont……
Papular acne
papule is caused by localized cellular reaction to the process of acne
Most patients with acne present with comedones and papules on the face and trunk.
Their formation begins with noninflammatory comedonal acne progressing to a small number of inflammatory lesions on the face, which then evolve into a more generalized eruption first on the face and then trunk.
Papule; Circumscribed raised lesion <1cm in diameter
This photo shows papules and comedones on the face of an acne patient
Pustular acne
dome-shaped, fragile lesion containing pus that typically consists of a mixture of white blood cells, dead skin cells, and bacteria
A pustule that forms over a sebaceous follicle usually has a hair in the center
Acne pustules that heal without progressing to cystic form usually leave no scars
Pustules; Circumscribed raised lesions containing cloudy fluid. >0.5cm in diameter, Not
necessarily infected
papules and comedones on the face of an acne patient
Nodule acne
Nodular acne is a severe form of acne that may not respond to therapies other than isotretinoin
Cyst
Larger than a pustule, may be severely inflamed, extends into deeper layers of the skin, may be very painful, and can result in scarring
Cysts and nodules often occur together in a severe form of acne called nodulocystic
Nodule; Circumscribed raised lesion >1cm in diameter
Unpleasant cystic acne in teenager
Clinical features
More common
• Lesions are limited to the face, shoulders, upper chest and back
• Seborrhea (greasy skin) is often present
• Open comedones (black heads) due to plugging by keratin and sebum of the pilosebaceous orifice
• Closed comedones (white heads) due to accretions of sebum and keratin deeper in the pilosebaceous ducts are always evident
• Scarring may follow
Less common
•Conglobate acne is severe with many abscesses and cysts
•Acne fulminans is a type of conglobate acne accompanies by fever joint pains and a high erythrocyte sedimentation rate
•Exogenous acne may be caused by tars, chlorinated hydrocarbons, oils and oily cosmetics; comedones dominate the clinical picture
•Drug induced acne may result from treatment with corticosteroids, androgenic steroids, lithium, oral contraceptives and anti convulsant therapy.
Severity rating for acne
Type 1: comedones only, fewer than 10 lesions on theface, no lesions on the trunk and no scarring
Type 2: papules, 10 to 25 lesions on the face and trunk,mild scarring
Type 3: pustules, more than 25 lesions, moderatescarring
Type 4: nodules or cysts, extensive scarring
Premenstrual exacerbations of acne are very common, with about 70 percent of women frequently experiencing flare-ups of acne two to seven days before the onset of menses and gradual improvement at the beginning of the next menstrual cycle
Certain cosmetic ingredients, such as lanolins, petroleum bases, cocoa butter and pomades, can precipitate acne development
Exacerbating factors
Medications That Cause Acne•Hormones
•Testosterone, a male hormone, can induce acne in females and in pre-adolescent children.
•Gonadotrophin that may be prescribed in certain pituitary disorders can indirectly induce acne by
stimulating testosterone production.
•Anabolic steroids are masculinizing hormones that can provoke or aggravate acne.
•Corticosteroids, taken orally or applied topically to the skin, may cause a degeneration of the
epithelial lining of sebaceous gland
•Anti-epileptic Drugs
•Individuals with severe epilepsy often have many endocrine (hormonal) problems, including
abnormal testosterone secretion.
•Anti-tuberculosis Drugs
•Isoniazid, the most widely used drug for treating tuberculosis, has been associated with
precipitation or aggravation of acne in small numbers of patients.
•Lithium
•Acne precipitation or aggravation is one of the dermatologic side effects of lithium, a medication
prescribed in the treatment of bipolar disorder.
•Cyclosporin
•Dermatologic reactions, including precipitation or aggravation of acne, are frequently seen in post-
transplant patients who must take cyclosporin to prevent organ rejection. Since cyclosporin cannot
be discontinued in a post-transplant patient, the side effect of acne should be treated by a
dermatologist.
•Halogenated Drugs
•Medications containing iodine or bromine can cause acne-like eruptions. These medications are
much less common today than in earlier years, but some are still in use. In the United States today, it
is probably more likely to see acne-like outbreaks resulting from heavy consumption of iodine-
containing health foods such as kelp. An acneiform eruption caused by eating large amounts of kelp
is seen in this photo:
Therapy
Goals of therapy
Relieving discomfort
Preventing pitting or scarring
Limiting psychosocial distress
Good skin hygiene is a basic tenet in acne prevention
Twice-daily cleansing with warm water and a mild soap can effectively remove excess sebum and improve skin appearance.
Aggressive skin washings will not alter the course of acne and may actually aggravate acne by promoting the development of inflammatory lesions.
Abrasive or antibacterial cleansers are not recommended, and squeezing or picking of acne lesions should be discouraged without the use of disinfectants
Drugs, cosmetics or other known precipitants also should be avoided.
Non-drug therapy
Drug therapy
Retinoids work to normalize follicular keratinization;
Isotretinoin and hormone manipulations decrease sebum production;
Antibiotics and benzoyl peroxide target P. acnes.
Antibiotics and retinoids also are used to prevent inflammation associated with bacterial colonization,
Topical therapy generally is preferred over systemic agents for mild to moderate acne.
Comedonal acne
Topical antibacterial agents, such as benzoyl peroxide, Comedolytic agents, such as salicylic acid and tretinoin(Retin-A), that unplug follicles with their exfoliative effects.
Is one of the most effective agents against acne vulgaris, causing mild desquamation and comedolysis by increasing epithelial cell turnoverand unblocking pores.
Its main effect is due to its antibacterial property of releasing free radicals and oxidizing bacterial protein. While benzoyl peroxide minimally reduces sebum production, it significantly lowers FFA concentrations
Benzoyl peroxide
A mild comedolytic agent agents with mild antibacterial activity
Combination of these agents are considered synergistic
It may actually enhance absorption of other topical agents when used concurrently.
A recent review shows that salicylic acid pads are safe, effective and superior to benzoyl peroxide in preventing and clearing both types of acne lesions.
Salicylic acid, and Sulfur
Have been used successfully to treat acne for many years.
Tretinoin (Retin-A(R)), also called all-trans-retinoic acid, is the naturally occurring form of vitamin A acid and is considered the most effective topical comedolytic agent.
Retinoids indirectly reduce P. acnes colonization by decreasing sebum production, a requisite for bacterial survival.
Vitamin A analogues
They also decrease horny cell cohesiveness by stimulating epidermal cell turnover and normalizing keratinization.
These actions unplug follicles, which ultimately prevents microcomedone formation
Considered highly effective agents because their pharmacologic activities target each of the four known pathogenic factors.
Adverse effects with retinoid therapy occur in nearly all patients, with dryness, rednessand peeling at the site of application topping the list.
Cont…… Vitamin A analogues
Exposure to sunlight can significantly intensify irritation to the skin. If sun exposure is unavoidable, patients should use a sunscreen with an SPF of at least 15.
Topical tretinoin may further darken skin in patients with dark complexion.
Patients should be made aware that improvement may take six to 12 weeks, and that flare-ups of acne can occur during the first few weeks of therapy.
Cont…… Vitamin A analogues
Topical antibiotics are effective in treating mild to moderate inflammatory acne, and they offer the advantage of direct topical application and less systemic absorption.
The side effects are minimal, the most common being mild burning or irritation.
They also can be used as an adjunct therapy in nodulocystic acne.
Papular acneCont……
Available in a 1% solution, lotion or gel (Cleocin-T);
Various studies show it to be as effective as topical erythromycin or oral tetracycline.
A 12-week course of 1% clindamycin solution
twice daily showed significant reduction in the number of inflammatory and noninflammatory acne lesions.
Rare cases of pseudomembranous colitis have been reported with topical use of clindamycin.
Clindamycin
Considered to be the safest acne agent to use during pregnancy.
It is available in a 2% solution (Eryderm),
Topical erythromycin
њGels usually have a high alcohol content that allows for
better absorption, but they also can be more drying.
Therefore, a cream or ointment may be better tolerated in
patients with sensitive skin.
њGels are useful for patients with oily skin.
њFor optimal results, the entire susceptible area, not just
the lesions, should be treated.
Vehicle consideration is important in topical formulations
Patients with moderate to severe inflammatory acne may require oral antibiotics in addition to topical therapy
Systemic antibiotics can achieve a more rapid clinical improvement, usually two to six weeks, with maximal clinical improvement in three to four months
The disadvantages of oral antibiotics, though, lie in their side effects: gastrointestinal distress and vaginal candidiasis.
Pustular acne
Twice-daily dosing of systemic antibiotics normally improves compliance, is usually as effective as more frequent dosing and may be used for chronic therapy
Long-term use of antibiotics has been found to be safe and effective in treating acne
Cont…… Pustular acne
Generally considered the first choice of oral agents in pustular acne due to its documented effectiveness and low cost
With a usual starting dose of 250 mg four times daily or 500 mg twice daily, 250 mg twice daily for four months also was found to be safe and effective in treating papulopustular acne, with 95 percent of patients showing clinical improvement
Tetracycline
The antibiotic of choice in acne if cost were not a consideration.
It is highly effective in acne treatment due to its lipid solubility and ability to penetrate the sebaceous follicle
Minocycline is used in patients with tetracycline-resistant acne and achieves good absorption even when administered with food.
Minocyline
Doxycycline Is less expensive than minocycline and its high lipid
profile also makes it a good agent in acne treatment
The usual dose is 100 mg once daily, and side effects include
photosensitivity and gastrointestinal distress
The usual dose of erythromycin is similar to that for tetracycline.
P. acnes resistance to erythromycin is more common than with
tetracyclines according to various studies and gastrointestinal side
effects limit its use.
Erythromycin, though, has the advantages of not inducing
photosensitivity and not interacting with antacids and dairy
products.
Trimethoprim-sulfamethoxazole is reserved for
severe cases of acne refractory to other antibiotics
Therapy initiated at one double-strength tablet of
trimethoprim - sulfamethoxazole daily
Potential side effects include rash, photosensitivity,
dizziness and Steven-Johnson's syndrome ―SJS, is an extreme
allergic reaction, usually to a drug, but also to certain bacterial and viral
infections‖, a severe eruption reaction.
Despite the relative success of antibiotic therapy, many patients do
not achieve full suppression of inflammatory lesions with continued
antibiotic usage, explanations for which include differences in
dosage regimens, drug absorption and patient compliance
Resistance to P. acnes should be considered in patients whose
response decreases with therapy that previously was successful
It did not become a problem until the mid 1970s, despite nearly two
decades of antibiotic usage
British studies reveal that resistance to erythromycin is most
prevalent, with the majority of the strains also being resistant to
clindamycin. Cross-resistance between tetracycline and doxycycline
also has been reported
Failure of antibiotic therapy
Treatment options for these patients include isotretinoin,
steroid injections and hormone therapy
Systemic antibiotics can also be used in treating cystic
acne, but long-term use may be limited by resistance and
adverse effects, including photosensitivity, gastrointestinal
disorders and vaginitis
Nodulocystic acne
Is a synthetic 13-cis-isomer of tretinoin, usually more effective than tretinoin and available as 10-, 20- or 40-mg oral capsules
It is the only systemic agent that decreases sebum production and reverses the abnormal epithelial desquamation process
It also can decrease the population of P. acnes in the sebaceous follicle, making it the treatment of choice for patients with severe nodulocystic acne
Isotretinoin
The initial dose of isotretinoin is 0.5 to 1.0 mg/kg or 40 mg to 80 mg per day, with a usual course of therapy of four to five months
Transient exacerbation of acne may occur during the first few weeks of therapy, but most patients respond well over time
Usually no further therapy is needed. Satisfactory response rate has been as high as 90 percent with a low relapse rate of 31 percent at nine years
Cont……
Adverse effects of systemic isotretinoin include cheilitis (lip inflammation), dry skin, pruritus, photosensitivity and mild to moderate musculoskeletal symptoms
Dryness of the eye also can occur, so patients wearing contacts should be warned not to wear them
Pseudo-tumor cerebri (benign intracranial hypertension) can occur if isotretinoin is taken concurrently with tetracycline
Cont……
Isotretinoin is contraindicated throughout pregnancy due to teratogenic effects
Contraception should be used throughout therapy and continued for at least one month after the last dose
Due to these serious adverse effects and overuse potential, strict guidelines exist for isotretinoin therapy
Cont……
Don't Pick!Not only does squeezing pimples cause further infection and inflammation, but it can also spread the bacteria (and the acne) from one pore to the next.
Acne 2007 SC
Acne 2007 SC
Acne 2007 SC
Acne 2007 SC
Acne 2007 SC