Acne is a common skin condition characterized by pimples on the face, chest, and back. It occurs when the pores of the skin become clogged with oil, dead skin cells, and bacteria.
(Fig.1.5.) Acne vulgaris affecting a woman's face. Acne is the general name given to a skin disorder in which the sebaceous glands become inflamed.
Acne originates in the oil or sebaceous glands that lie just beneath the surface of the skin, within the hair follicles. These glands produce an oil called sebum-the skin's natural moisturizer-which also helps preserve the flexibility of the hair. These sebaceous follicles open onto the skin through pores, allowing the sebum to reach the hair and skin surface. The most common sites of acne are the face, chest, shoulders, and back since these have the most sebaceous follicles.
At puberty increased levels of androgens (male hormones) cause the sebaceous glands to overproduce sebum. The excess sebum cannot be cleared from the pores efficiently. In addition, cells lining the follicle are shed too quickly and the dead cells clump together. When the excess sebumcombines with the dead, sticky skin cells, a hard plug-called a comedo-forms and blocks the pore. There are two types of comedones in mild noninflammatory acne: whiteheads and blackheads. When the plugged follicle begins to bulge as a small whitish bump mostly under the skin, it is called a whitehead. If the comedo opens up, the top surface of the plug darkens as it is exposed to the air and it is referred to as a blackhead.
Moderate and severe inflammatory acnes result from infection of plugged follicles with Propionibacterium acnes, bacteria that normally live on the skin. Other microorganisms can also be involved. The bacteria produce chemicals and enzymes that cause inflammation. Pimples form when infected whiteheads or blackheads weaken and burst, releasing sebum, bacteria, and skin and white blood cells into the surrounding tissues. Inflamed pimples near the skin surface are called papules. Deeper pimples that fill with pus are called pustules. The most severe type of acne occurs when the infected follicles continue to enlarge without rupturing, forming nodules and cysts. Cysts are closed sacs that form lumps under the skin. Nodules are large hard swellings deep within the skin. Cysts and nodules can be painful and scarring can occur when new skin cells are laid down to replace damaged cells.
Acne is not a serious health threat. However, it can negatively affect appearance and has the potential of causing permanent scarring. Some people, especially teenagers, become quite upset about their acne and this distress can contribute to social or psychological problems.
Risk factors for acne include:
The exact cause of most cases of acne is unknown. Contrary to popular myth, acne is not caused or aggravated by dirt, by eating greasy foods or chocolate, or by sexual activity. Many factors, including heredity, can contribute to the development of acne. The interactions between the body's hormones, skin proteins and secretions, and bacteria determine the course of acne.
Excess male hormone production in women can cause acne. Flare-ups of acne are also influenced by a woman's menstrual cycle. One study found that women over age 33 actually had a higher incidence of premenstrual acne than teenage girls.
Some alternative medical practitioners assert that acne is often related to toxicity in the intestines or liver due to:
Acne has a characteristic appearance and is not difficult to diagnose. The doctor takes a complete medical history, including questions about skin care, diet, factors that seem to improve or exacerbate the condition, medication use, and prior treatment. A physical examination includes the face, upper neck, chest, shoulders, back, and other affected areas. Under good lighting the doctor determines the number and types of blemishes, whether they are inflamed, whether they are deep or superficial, and whether there is skin discoloration or scarring.
Laboratory tests are not performed unless the acne appears to be caused by a hormonal disorder or other underlying medical problem. In these cases, blood analyses or other tests may be ordered. Stool tests can be helpful in determining whether there is a bacterial or yeast overgrowth contributing to the condition. Food-allergy testing may also be considered. Most insurance plans cover the costs of diagnosing and treating acne.
Acne cannot be cured, but it can be controlled. The goal of acne treatment is to reduce sebum and keratin production, remove dead skin cells to help unclog the pores, and kill bacteria with topical drugs and oral medications. Treatment choice depends upon whether the acne is mild, moderate, or severe. Severe cases are referred to a dermatologist or an endocrinologist who treats diseases of the glands and the hormones. Most dermatologists use a combination of treatments, depending on the individual. Counseling may be necessary to clear up misconceptions about the condition and to offer support regarding the negative effect of acne on physical appearance.
In addition to medications, treatments for severe acne or the resulting scars include:
Mild non-inflammatory acne is usually treated with topical over-the-counter acne medications that reduce the formation of new comedones. These may contain:
Treatment with stronger topical medications requires a doctor's prescription. Such medications include comedolytics, which are agents that loosen hard plugs and open pores. These include concentrated formulas of salicylic acid, resorcinol, and sulfur. They also include topical retinoids-natural or synthetic vitamin A derivatives-which increase turnover (death and replacement) of skin cells. Topical retinoids are considered a cornerstone of acne treatment:
Topical antibiotics to kill bacteria may be added to the treatment regimen if inflammation is present. These include:
Topical medications are available as creams, gels, lotions, soaps, or pads of varying strengths. The medications are applied to the entire affected skin area once or twice per day after washing with mild soap. Possible side effects include mild redness, peeling, irritation, dryness, and an increased sensitivity to sunlight that requires the use of a sunscreen. Medications may be used for months or years to control acne. The goal of treating moderate acne is to decrease inflammation as well as prevent new comedone formation. Common treatments are topical tretinoin combined with a topical or oral antibiotic or topical benzoyl peroxide and erythromycin. The treatment is maintained for at least two to four months. When acne is severe and the lesions are deep, oral antibiotics may be taken daily to reduce the spread of bacteria:
Antibiotics must be used for up to three months to affect severe acne. They can cause side effects including:
Oral isotretinoin (Accutane) reduces sebum production and cell stickiness. It is reserved for the treatment of very severe acne with cysts and nodules or if antibiotic therapy is unsuccessful. Isotretinoin is sometimes used in combination with topical or oral antibiotics. Treatment may continue for four to five months and may be repeated or replaced with topical drugs or oral antibiotics if the acne returns. Lower dosages require a longer course of therapy.
Women who might become pregnant should use isotretinoin with extreme caution, since it can cause birth defects and miscarriage up to a month after stopping the medication. Strict attention should be paid to pregnancy tests and contraceptive requirements for women of childbearing age who take this medication. Side effects of isotretinoin are very common and may include:
Monthly blood tests are necessary to ensure that the medication is not causing serious harm. Anti-androgens-drugs that inhibit androgen production-and estrogens (female hormones) are used to treat women whose acne is unresponsive to other therapies. Certain types of oral contraceptives, such as norgestimate/ethinyl estradiol (Ortho-Tri-Cyclen), have been shown to improve acne. Both ultra-low-dose birth-control pills (Alesse) and those with higher doses of estrogen can be effective in treating acne.
Other drugs, such as spironolactone and oral corticosteroids or anti-inflammatory drugs, may be used to reduce hormone activity in the adrenal glands, thereby reducing production of sebum. This is the treatment of choice for an extremely severe but rare type of inflammatory acne called acne fulminans, which primarily affects adolescent males. Acne conglobata is a more common form of severe inflammation characterized by numerous, deep, inflammatory nodules that heal with scarring. It is treated with oral isotretinoin and corticosteroids.
In addition to proper cleansing to keep the skin free of oil, alternative treatments for acne include:
Nutritional supplements for treating acne include:
Supplementation with herbs that are blood cleansers or blood purifiers, strengthen the action of the liver and the kidneys, and help with detoxification and excretion are used to treat acne. These include:
Other herbs useful in the treatment of acne include:
Bowel toxicity may contribute to acne flare-ups. Lactobacillus acidophilus and Lactobacillus bulgaricus can be obtained from yogurt or as capsules to maintain a healthy balance of intestinal flora. Allergic foods should be identified and removed from the diet. Dietary fiber, such as oat and wheat bran, beans, fruits and vegetables and their skins, and psyllium seed, should be increased. The fiber absorbs toxins and carries them through the colon for excretion. Individuals with acne may want to participate in a movement therapy, such as yoga or t'ai chi, or begin an exercise regimen. Stress reduction or meditation can also be helpful.
Washing the acne-affected area with a mild germicidal soap and an abrasive sponge can help dislodge the material plugging the gland. However manipulating or squeezing acne pustules can cause deep and permanent scarring.
Acne is not curable, but it can be controlled by proper treatment. Improvement takes time and the results of specific treatments vary with the individual. Over-the-counter treatments for mild non-inflammatory acne can help prevent new blemishes, although it often takes 8-10 weeks to see improvement, as old blemishes take time heal. Inflammatory acne that is treated with a topical comedolytic in combination with an antibiotic usually improves within four to six weeks. Acne tends to reappear when treatment stops, but spontaneously improves over time. Inflammatory acne can leave scars that require further treatment.
Oral isotretinoin clears up resistant cysts and nodules in up to 90% of patients and prevents scarring. Long-term control is achieved in up to 60% of patients treated for four to five months. Another 20% of patients require a second course of isotretinoin and the final 20% may require only topical drugs or oral antibiotics. Improvement with anti-androgens may take up to four months.
There is no sure way to prevent acne, but the following steps may help minimize flare-ups: