What Is Acne?

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Chapter 1
What Is Acne?

Acne is a common skin disease that affects tiny ducts in the skin where hair grows. These ducts are known as follicles. Acne occurs when the follicles become clogged and infected. This causes sores known as acne lesions, or pimples, to develop on and under the skin.

Excess Hormones Cause Excess Oil Production

There are a number of factors that cause the follicles to become clogged and infected. One important factor is the overproduction of androgen. Androgen is a chemical, or male sex hormone, that both males and females normally produce. However, hormonal changes in the body during puberty, pregnancy, or the female menstrual cycle cause some people to produce higher than usual levels of androgen. Although scientists are unsure why, excess androgen stimulates the sebaceous oil glands inside the follicles to enlarge and manufacture excess amounts of oil called sebum. Whereas the normal production of sebum is necessary for healthy skin, excess sebum leads to the development of acne.

Normally, the sebaceous oil glands produce small amounts of sebum, whose job it is to moisten and protect the skin. In order to do this, sebum works its way up through the hair follicles, where it washes away dead cells that accumulate in the follicles. Then sebum empties onto the skin through tiny openings in the follicles called pores. Here sebum protects the skin from bacteria that live on the skin by washing the bacteria away.

However, when excess sebum is produced, it accumulates in the follicles rather than spilling out onto the surface of the skin. This occurs because the follicles are extremely small and narrow. Therefore, large volumes of sebum cannot pass through the follicles to the surface of the skin at the rate the sebum is produced. Instead, sebum becomes trapped in the follicles, where it mixes with dead skin cells, forms sticky plugs that block the pores, and prevents sebum from reaching the surface of the skin. As a result, the skin around the clogged follicles dries out. At the same time, since not every follicle becomes clogged, excess oil that spills onto the skin through unclogged follicles causes the skin to feel oily. Therefore, a person with acne may have dry skin around clogged follicles and oily skin everywhere else.

Worse yet, without sebum to wash away bacteria on the skin, bacteria grow and multiply around the clogged follicles. Eventually, bacteria get inside the clogged follicles, where they mix with sebum and dead cells and cause an infection. This most commonly occurs on the parts of the body that have the largest sebaceous glands, such as the face, chest, neck, shoulders, upper back, and buttocks. The result is the development of one type of acne lesion known as a comedone.

Inflammation Makes Acne Worse

Unfortunately, the damage does not end there. Once bacteria enter the follicles, the immune system, which protects the body from infection and disease, reacts. Blood, rich with infection-fighting white blood cells, rushes to the area. As the infection worsens, pus and other powerful chemicals are also produced to combat the infection. This causes the infected area to become hot, red, swollen, and painful.

Heat, redness, swelling, pain, and the presence of pus are all characteristics of inflammation, which in the case of acne appears on the skin in the form of papules, pustules, and cysts, other types of acne lesions.

Different Types of Lesions

Whether a person develops comedones, papules, pustules, cysts, or a combination of these lesions depends on how severely the hair follicles are clogged and inflamed. The worse the inflammation, the more severe the acne lesion. For example, comedones, which are basically enlarged, clogged hair follicles, form before the hair follicles become inflamed or in the earliest stages of inflammation. Comedones contain sebum, dead skin cells, and bacteria that are trapped in the follicles, but comedones do not contain pus, nor are they red or swollen. That is why comedones are the least severe type of acne lesion.

Since comedones do not contain pus, they are quite small. All comedones have either a white or black tip. Hence, comedones are commonly known as whiteheads or blackheads.

Whiteheads and Blackheads

Whiteheads look like small white bumps and are usually about the size of a pinhead. They form under the skin as the follicles become more and more clogged and enlarged. Whiteheads never reach the skin's surface or open up. Therefore, they are called closed comedones.

Blackheads, on the other hand, are closed comedones that continue to grow upward until they break through the skin's surface. At this point, the enlarged hair follicle is visible and open to the skin's surface. For this reason, blackheads are known as open comedones.

To the naked eye the contents of an open comedone look black. The black color is the result of oxidation, a process of discoloration that occurs when dead cells, sebum, and bacteria mix with oxygen in the air. However, some people mistakenly think that dirt trapped under the skin causes an open comedone to appear black. A young man recalls how this misconception affected him: "I had black-heads all over my forehead and nose. I scrubbed my face constantly, trying to scrub the dirt out of those blackheads. But I kept getting more. I couldn't understand where all the dirt was coming from."7

Since comedones do not form as a result of severe inflammation, they are not painful, no matter whether they are blackheads or whiteheads. Moreover, because comedones are not large, red, or pus filled, when seen from a distance, the skin of people with comedones, especially those with whiteheads, appears relatively clear. However, because comedones are enlarged, clogged follicles, they do not disappear until the follicles unclog. This may not occur under normal circumstances until sebum production decreases or the patient receives effective acne treatment. Therefore, whiteheads and blackheads often stay on or under the skin for a long time.

Even more troubling, some closed comedones do not grow upward and become open comedones. Instead, as they become more and more packed with sebum, they grow downward under the surface of the skin and continue to enlarge until they burst. This results in the formation of more serious acne lesions such as papules and pustules.

Papules and Pustules

When closed comedones burst, their contents get into surrounding tissues. In response, the immune system sends more blood to the area, which causes inflammation to begin or worsen. As a result, the closed comedone and the area surrounding it become red and swollen. This redness and swelling appears on the skin in the form of a papule.

Papules are small, firm, red bumps. They are only mildly inflamed because they form before pus has reached the area. Therefore, papules are more severe acne lesions than comedones, but milder than acne lesions that contain pus. However, because papules are inflamed, they are often tender to the touch.

As the inflammation worsens, the immune system sends pus to the area. When this happens, pustules form. Because pustules are caused by severe inflammation, they often feel hot and may be quite sensitive to the touch.

Not surprisingly, pustules are larger than papules. They are often about the size of the tip of a person's little finger. Pustules are red at the base, with a yellowish, pus-filled inner region. A man who had pustules on his face, shoulders, and neck recalls: "They were big old welts filled with white poison and surrounded by red rings."8

Although a pustule's red base forms on the surface of the skin, the pus-filled core is near, but still underneath, the skin. However, as inflammation worsens and more pus is formed in the area, the pus-filled core of a pustule begins to swell like a balloon. When this happens, it is not uncommon for pustules to pop open and spill pus onto the skin. A man recalls: "In the morning before I went to school, I'd have big welts on my shoulders and neck. Sometimes at school they would break without me even knowing. When I got home I'd have stains on my shirt."9

Cysts

Just as worsening inflammation causes a pustule to expand upward through the skin's surface, worsening inflammation also causes pustules to expand downward. When this occurs, a cyst is formed. Cysts are packed with large amounts of pus that extend deep below the skin's surface. Due to swelling, cysts may be several centimeters in diameter. Most cysts are red or purple and extremely painful. Since cysts form when inflammation and infection are the most severe, cysts are the most serious type of acne lesions.

Three Types of Acne

Just as there are different types of acne lesions, there are also different types of acne. Although there are a number of rare forms of acne, most experts divide acne into three main types: comedonal acne, acne vulgaris, and cystic acne.

The first type, comedonal acne, consists of whiteheads and black-heads alone, without the presence of other acne lesions. Therefore, comedonal acne is the mildest form of acne. However, since closed comedones often burst and become inflamed, it is not uncommon for people with comedonal acne eventually to develop papules and pustules.

When people have a mix of comedones, papules, and pustules, they have acne vulgaris, or common acne. A man who suffered from acne vulgaris recalls: "I had them all. I had blackheads on my nose. I had whiteheads on my forehead. I had bumpy red pimples and big pus pimples on my chin, neck, back, and shoulders."10

Acne vulgaris is the most common form of acne, affecting approximately 90 percent of all people with acne. Acne vulgaris can be mild, moderate, or severe, depending on the number of acne lesions a person has and how severely the lesions are inflamed.

The third type of acne, cystic acne, is the most severe form of acne. The presence of comedones, papules, pustules, and numerous acne cysts characterize cystic acne. Because cysts are caused by severe inflammation and infection, cystic acne can be quite painful.

Making matters worse, if cystic acne is left untreated, the severe inflammation and infection that cause cystic acne can damage surrounding tissues. This frequently leaves the skin of people with cystic acne permanently scarred. A patient explains: "You can see the scars where I had cysts today. They look like little craters. You can see them on my neck and on my back. I've got a little bit of evidence on my face too. Wherever you see a crater, that's where I had a cyst."11

People at Risk

Although almost everyone has an occasional whitehead or black-head, certain groups are more likely to develop acne vulgaris and cystic acne than others. These include adolescents, adult women, people under stress, people taking certain medications, and people whose parents had acne.

Acne in Adolescents

Adolescents are the largest group at risk of developing acne. This is because acne usually begins during puberty, when the body starts producing androgen. Androgen production is usually at its peak when people are between the ages of twelve and seventeen. Therefore, more oil is produced in the hair follicles of adolescents than in any other age group. As a result, experts estimate that more than 85 percent of all adolescents between the ages of twelve and seventeen develop some form of acne. This translates to more than 20 million teenagers in the United States. Moreover, although both males and females produce androgen, adolescent males produce ten times more androgen than females do because androgen is a male sex hormone. Consequently, it is not surprising that adolescent boys are more likely to develop severe cases of acne vulgaris as well as cystic acne; whereas teenage girls are more likely to develop comedonal acne and mild cases of acne vulgaris.

Generally, oil production decreases after the age of seventeen. In most cases, as androgen and sebum levels decrease, so does acne. Thus, by the time most adolescents reach age eighteen, their acne symptoms begin to subside and disappear. However, approximately 30 percent of all adolescents with acne continue to be plagued with acne for the rest of their lives. According to acne expert and dermatologist Anthony C. Chu, "Acne can persist well into old age and I have a number of patients in their sixties, seventies, and even eighties who still have active acne. Acne is, therefore, not merely a teenage occurrence; it can affect you at any time of your life."12

Adult Women and Acne

One group that is affected by acne well beyond adolescence is adult women. An estimated 5 percent of adult women have persistent acne that does not subside after puberty. An even larger number develop acne when they reach their twenties or thirties. Many of these women did not have acne as teenagers, while others had acne during their teen years that disappeared when puberty ended. Then, when these women reach their twenties or thirties, acne symptoms reappear as a result of fluctuating hormone levels caused by pregnancy, their monthly menstrual cycle, or hormonal imbalances. In fact, experts estimate that as many as 50 percent of all adult women suffer from acne. A woman describes her experience: "I had acne in high school. Luckily, it cleared up my senior year and my face was pretty clear through college. Now I am twenty-six, and started getting acne again."13

Some women experience only occasional acne flare-ups. Since the female menstrual cycle causes hormone levels to rise and fall, many experts believe these flare-ups occur when lower than normal levels of the female sex hormone, estrogen, are being produced. Estrogen is known to counterbalance the production of androgen. Therefore, without sufficient estrogen, androgen production increases unchecked, leading to acne flare-ups. At other times, when estrogen levels are high and androgen levels are low, these women's skin remains clear. Experts are unsure why this problem does not affect all women, but they theorize it is more likely to occur in women who, for unknown reasons, have the greatest fluctuation in their hormone levels.

Similarly, acne often flares up at different times during pregnancy as a pregnant woman's hormone levels change in order to accommodate her body's changing needs. Comparable hormonal changes often occur in some women after they give birth. As a result, some adult women develop acne shortly after their babies are born.

People Under Stress

Stress is another factor that can change hormone levels in adult women, men, and adolescents. Although scientists do not believe that stress directly causes acne, numerous studies have linked stress and acne flare-ups. The reason for this link is that when the body is under stress, it responds by producing hormones, including androgen and cortisol. Cortisol, like androgen, stimulates oil production. Therefore, people who are under stress are at risk of developing acne or having their existing acne worsen. Moreover, even though the production of stress hormones decreases as a person relaxes, stress-induced acne flare-ups often do not clear up until the inflammation heals. This may take a week or more.

Chu describes how stress affects his patients: "I have looked after four women who have cancelled their weddings on at least one occasion. Each time they neared their wedding day, stress levels increased and their spots became so bad that they cancelled because they could not bear the thought of wedding photographs of themselves covered with spots."14

People Taking Medication

Just as stress can change hormone levels, certain medications can also have this effect. For example, although some birth control pills contain estrogen, which lowers androgen levels, one type of birth control pill contains progesterone, a hormone that stimulates the body to produce androgen, which can make acne worse. Other medicines such as those used to treat epilepsy, a disorder that causes seizures, and anabolic steroids, drugs often used illegally by athletes and bodybuilders to stimulate muscle growth, stimulate the production of androgen and have been linked to acne.

Genetics

Genetics also plays a role in determining who is at risk of developing acne. Experts agree that acne seems to run in families and that there seems to be a direct link between the development of severe acne and familial patterns. Experts are unsure why this is so, since an acne gene has not yet been discovered. However, a number of studies have shown that genetics does play a role in determining how likely a person is to develop acne. Various studies of identical twins, for example, found in over 50 percent of all cases that if one twin develops acne so does the other. Correspondingly, other studies have shown similarities among parents and children regarding the types of acne lesions, the severity of acne, and the duration of acne. A patient with acne explains: "I inherited it [acne] from my mother, and she's always telling me that she had the exact same thing and that it will go away. I am mad that I inherited it from her."15

Physical Effects of Acne

No matter who gets acne, acne can have a long-lasting physical effect. Acne lesions can leave permanent scars on an acne patient's skin. When a clogged hair follicle becomes infected, and the body sends white blood cells and powerful chemicals to combat the infection, swelling causes tissue around the infected follicle to be damaged. In many cases, once the infection is gone, the tissue is too damaged to return to its normal state. This damage appears in two distinct types of acne scars, scars caused by increased tissue formation and scars caused by tissue loss.

Scars caused by increased tissue formation are called keloid scars. Keloid scars form when the skin responds to tissue injury by producing an excess of collagen, a substance that helps the skin regenerate. Too much collagen causes the production of excess tissue to form over the damaged area. The results are keloid scars, which look like firm, shiny, flesh-colored lumps.

Acne scars that are caused by tissue loss occur when the body is unable to completely rebuild damaged tissue. Often called depressed, ice-pick, or pitted scars, these scars look like the skin has been pushed in, forming a soft depression with puckered edges. Pitted scars can be quite small, or they can be over a centimeter in diameter. Pitted scars are the most common type of acne scar and are commonly found on the face, back, and shoulders.

Fortunately, not every person who has acne develops acne scars. Doctors are unable to predict accurately whether or not a person with acne will develop scars. However, in most cases, as the severity of a person's acne increases so does the amount of tissue damage. Since acne scars result from damaged tissue, individuals who suffer the most tissue damage are most at risk of developing acne scars. Generally, these are individuals with severe cases of acne.

Emotional Effects of Acne

Even when acne does not cause permanent scars, because acne affects a person's appearance it can take an emotional toll on a person. People with acne often feel self-conscious about their appearance. Over time, their self-esteem and self-confidence decrease. This makes them feel insecure and anxious in social situations. In fact, many people with acne avoid social situations due to self-consciousness about their appearance. Indeed, many become shy and withdrawn. A young man explains: "I've lived with really heavy acne for the last five years. I feel so self-conscious that I don't even like going out. It's ruined my confidence."16

The combination of low self-esteem, embarrassment, and increasing social isolation leads many people with acne to become depressed. When people are depressed, they often lose interest in daily activities and feel tired, anxious, and unhappy. Some may contemplate suicide. In fact, according to a 2002 survey by the Acne Support Group, a British organization that helps acne sufferers, 15 percent of the acne patients surveyed reported feeling suicidal, and 75 percent reported feeling depressed because of acne. An acne patient describes how acne-caused depression affected her: "I did not look in mirrors whatsoever. I walked into a room and immediately shut out the light. Everything I did, I did in darkness because any time I caught a glimpse of myself I felt suicidal."17

Truly, many people with acne bear both emotional and physical scars all their lives. A former acne patient explains:

It's easy to see the scars on my back and neck. What you can't see is what it did to me inside. I went from a fairly self-confident kid to an angry, withdrawn, and embarrassed teenager. Even today, the memories of the teasing and the embarrassment are quite vivid. It makes me queasy just to think about it. Even when the pimples are gone, acne stays with you a long time.18