Overview
Vitiligo (vit-ih-LIE-go) is a disease that causes the loss of skin color in blotches. The extent and rate of color loss from vitiligo is unpredictable. It can affect the skin on any part of your body. It may also affect hair and the inside of the mouth.

Normally, the color of hair and skin is determined by melanin. Vitiligo occurs when the cells that produce melanin die or stop functioning. Vitiligo affects people of all skin types, but it may be more noticeable in people with darker skin. The condition is not life-threatening or contagious. It can be stressful or make you feel bad about yourself.

Treatment for vitiligo may restore color to the affected skin. But it does not prevent continued loss of skin color or a recurrence.

Symptoms
The main sign of vitiligo is patchy loss of skin color. Usually, the discoloration first shows on sun-exposed areas, such as the hands, feet, arms, face and lips.

Vitiligo signs include:

Patchy loss of skin color
Premature whitening or graying of the hair on your scalp, eyelashes, eyebrows or beard
Loss of color in the tissues that line the inside of your mouth and nose (mucous membranes)
Loss of or change in color of the inner layer of the eyeball (retina)
Vitiligo can start at any age, but often appears before age 20.

Depending on the type of vitiligo you have, the discolored patches may cover:

Many parts of your body. With this most common type, called generalized vitiligo, the discolored patches often progress similarly on corresponding body parts (symmetrically).
Only one side or part of your body. This type, called segmental vitiligo, tends to occur at a younger age, progress for a year or two, then stop.
One or only a few areas of your body. This type is called localized (focal) vitiligo.
It's difficult to predict how your disease will progress. Sometimes the patches stop forming without treatment. In most cases, pigment loss spreads and eventually involves most of your skin. Rarely, the skin gets its color back.

When to see a doctor
See your doctor if areas of your skin, hair or eyes lose coloring. Vitiligo has no cure. But treatment may help to stop or slow the discoloring process and return some color to your skin.

Causes
Vitiligo occurs when pigment-producing cells (melanocytes) die or stop producing melanin — the pigment that gives your skin, hair and eyes color. The involved patches of skin become lighter or white. Doctors don't know why the cells fail or die. It may be related to:

A disorder in which your immune system attacks and destroys the melanocytes in the skin
Family history (heredity)
A trigger event, such as sunburn, stress or exposure to industrial chemicals
Complications
People with vitiligo may be at increased risk of:

Social or psychological distress
Sunburn and skin cancer
Eye problems, such as inflammation of the iris (iritis)
Hearing loss

Skin cancer is the most common type of cancer diagnosed in the United States and can be broken down into squamous cell cancers, basal cell cancers, and melanomas, as well as some less common cancers. Symptoms may include a sore that doesn't heal, a new spot on the skin, or a mole that is changing. When doctors suspect skin cancer during an exam, a biopsy is needed to make the diagnosis. Treatment options depend on the type and stage, with surgery to remove cancer being the most common approach. With melanomas and advanced squamous cell carcinomas, other treatments such as immunotherapy, chemotherapy, or radiation may be needed. Luckily, there are many simple things you can do to lower your risk.

At the current time, skin cancer is considered an epidemic in the United States, accounting for 50 percent of all cancers. Roughly 80 percent of skin cancer-related deaths are due to melanoma.

Your Skin
Many people do not think of the skin as an organ, but like other organs, it has a discrete structure and many important functions. Since treatment options for skin cancer often depend on the depth of cancer, it's helpful to understand the three basic layers of the skin.

Epidermis

The epidermis is the top layer of skin and serves several functions, including protecting the interior of your body from the environment. Cells in this layer include the following, which give rise to the most common skin cancers—squamous cell carcinoma, basal cell carcinoma, and melanoma:

Squamous cells lie just below the outer surface of the skin.
Basal cells lie beneath the squamous layer and produce new skin cells.
Melanocytes are located in the basal cell layer of the skin and produce melanin, the pigment that gives skin its color.
Dermis

The dermis is the middle layer of skin made up of collagen and elastin. It contains hair follicles, oil-producing glands (sebaceous glands), nerves, and blood vessels.

Subcutaneous Tissues

The subcutaneous tissue contains fat, connective tissue, and larger blood vessels; the amount of this tissue varies depending on a person's weight.

Types
There are three common types of skin cancer and more than 100 less common types. Together, basal cell carcinoma, and squamous cell carcinoma are referred to as non-melanoma skin cancers.

Basal Cell Carcinoma

Basal cell carcinoma (BCC) is the most common form of skin cancer, accounting for 75 percent to 80 percent of these cancers. The lifetime risk of developing a basal cell carcinoma is around 30 percent. It was once found mostly in middle-aged or older people, but is increasingly being found in younger people. It is the most common skin cancer among Hispanics.

Basal cell carcinoma usually begins on areas exposed to the sun, such as the face, neck, and hands. It is slow-growing cancer that rarely spreads to other parts of the body, but people with a history of BCC are at higher risk for getting a second case.

Cancer originates in the basal cell layer of the epidermis (the stratum basale). The basal cells there mutate and begin to replicate uncontrollably. As the cancerous cells grow, they can spread into the dermis, nearby lymph nodes, and may eventually invade bones. If not treated, they can damage the surrounding tissue, causing disfigurement.

Treatments are very effective when these cancers are found and treated promptly.

Squamous Cell Carcinoma

Squamous cell carcinoma (SCC) accounts for 16 percent to 20 percent of skin cancers and occurs twice as often in men as in women. These are the most common type of skin cancers found in blacks.

Unlike basal cell carcinomas, these cancers may spread (metastasize) if they become large. It usually occurs on the face, ear, neck, lips, and backs of the hands. SCC can also begin within scars or skin ulcers on other places on the body. As with basal cell carcinoma, the available treatments are very effective if the tumor is detected while it is small and thin.

Squamous cell carcinomas have the strongest association with sun exposure.

Melanoma

Melanoma is the most feared type of skin cancer. Though less common than basal cell and squamous cell cancer, it is responsible for the majority of deaths from the disease as a whole. Melanoma may arise in normal skin but often begins in an existing mole. It is found most frequently on the back in men, on the legs in women, and on the palms of the hands, soles of the feet, and under the fingernails or toenails of people of both sexes with darker skin colors. That said, these cancers may occur anywhere, including areas of the skin that have never been exposed to the sun.

The incidence of melanoma has been rising dramatically in the United States for the last three decades. While melanoma in general is 20 times more common in whites, the incidence of cases that occur under the nails is similar for people of all skin color. In addition, the survival rate in those diagnosed is lower in blacks.

The prognosis of melanoma is good when found early, but drops precipitously when it spreads to distant lymph nodes or organs, such as the bones, the lungs, the liver, and the brain. Newer treatments, however, are making a difference in survival, and even some advanced melanomas can now be controlled with these options.

Rare Types

The other types of cancer that can arise in the skin or skin-related structures are far less common. A few of these include:

Merkel cell carcinoma: Merkel cell carcinomas are rare skin cancers most often found around the eye in middle-aged people. For unknown reasons, these cancers are increasing. They tend to be aggressive and spread rapidly to other parts of the body.
Kaposi's sarcoma: This cancer is caused by the Kaposi sarcoma herpesvirus, and is usually found in people with HIV/AIDS or who are immunosuppressed for other reasons, such as an organ transplant. It presents as large red, blue, or brown splotches around the body along with swelling that can be severe. Fortunately, it often responds well to HIV medications.
Sebaceous gland carcinoma: These cancers originate in sebaceous glands and occur most often in older women, around the eye.
Dermatofibrosarcoma protuberance: These cancers begin as a hard nodule that originates in the dermis and spreads rapidly. They are related to a gene mutation that results in overproduction of a protein known as a platelet-derived growth factor.
Skin Metastases and Other Cancers That Occur in the Skin

Sometimes, cancers that arise in other areas of the body may spread (metastasize) to the skin. Cancers most commonly associated with skin metastases include breast cancer, colon cancer, and lung cancer. When other cancers spread to the skin they are not classified as skin cancer. In fact, though cancer may now be affecting the skin, its cells are clearly identifiable as belonging to instigating cancer when examined under a microscope. Treatment for cancer at play, rather than skin cancer, is needed.

Some examples of this include inflammatory breast cancer, which often begins with redness and a rash on the breast); Paget's disease, a form of breast cancer that begins on the skin of the nipples; and cutaneous T cell lymphomas (including mycosis fungoides and Sezary syndrome), which often begin as flat, red patches of skin that are extremely itchy.

Symptoms
Signs and symptoms of skin cancer may include any change that is noted on the skin, such as:

A sore that doesn't heal
A mole that is changing
Scaly, crusty appearing lesions
Pink, white, or flesh-colored lumps that appear dome-like
Itching
Some refer to the ABCDE (and F) mnemonic to help them recognize when a skin change could be skin cancer:

A stands for asymmetry: A mole or sore that is asymmetric.
B stands for borders. The borders of a melanoma may be irregular, notched, or blurry.
C stands for color. Melanomas often have more than one color or hue.
D stands for diameter. A mole that is larger than a pencil eraser is more likely to be a melanoma.
E stands for either elevation or evolution. The mole may be elevated (often irregularly) and is often evolving (changing) over time.
F: Though an unofficial qualifier, many add this to represent a skin change that is "funny" looking.
What Are the Most Common Skin Cancer Symptoms?
Causes and Risk Factors
We don't know exactly what causes skin cancer, though we have identified several risk factors. Some of these include:

Sun exposure (especially extensive and/or unprotected)
Pale skin
Red or blonde hair
Light eyes (green or blue eyes)
Skin that rarely tans and burns easily
Family and/or personal history of skin cancer
Having one of several genetic syndromes, such as xeroderma pigmentosum
Having many moles (more than 50) or having atypical moles (nevi)
Scars from burns or previous skin infections
A weakened immune system
Use of some medical treatments and medications, such as radiation therapy for cancer and ultraviolet light for psoriasis
Frequent exposure to chemicals such as tar and vinyl chloride
Exposure to arsenic in drinking water
Smoking (increases the risk of squamous cell carcinoma)

Causes and Risk Factors of Skin Cancer
Diagnosis
Diagnosing skin cancer begins with a careful history (paying attention to symptoms and risk factors) and a physical exam. Based on the appearance of the skin lesion, a doctor may recommend a biopsy, as it can sometimes be difficult to know whether an abnormality is cancer or not based on its visible appearance. This can be even more challenging in non-white populations.

A biopsy can be done in one of several ways, including:

Shave biopsy: The most common if a basal cell or squamous cell carcinoma is suspected), this procedure involves numbing the skin and shaving off a piece of the lesion. A punch biopsy may also be done.
Incisional biopsy: An incision is made and part of an abnormality is removed to be viewed by a pathologist.
Excisional biopsy: In this case, the entire abnormality is removed, along with an area of surrounding tissue, for a pathologist's evaluation. This is done if a melanoma is suspected.
If a skin cancer (melanoma and sometimes squamous cell carcinoma) is advanced, further tests are done to stage the disease and search for the presence of metastases. These may include a sentinel node biopsy, CT scans, a PET scan, or other tests depending on the location of the skin cancer.

How Skin Cancer Is Diagnosed
Treatments
The treatments for skin cancer will depend on many factors, such as the type of cancer, the size and depth, and more.

Surgically removing the tumor is the most common treatment. A special surgery called Mohs surgery involves removing successive pieces of tissue and checking the margins for any evidence of cancer so that the least amount of surgery to completely remove the tumor is done. With melanomas, a large area of surrounding tissue is removed.

For more advanced tumors that have spread to lymph nodes or other regions of the body, treatments such as immunotherapy, chemotherapy, targeted therapy, and radiation therapy may be needed.

What Are Your Skin Cancer Treatment Options?
Prevention and Early Detection
There are many things you can do to prevent skin cancer or at least reduce your risk. Being careful in the sun is important, but includes more than just wearing sunscreen; using other methods of protection (such as wearing clothing and hats, and avoiding mid-day sun) should be practiced as well. Some occupational exposures may increase risk, and gloves are recommended when working with many different chemicals and substances.

Not all skin cancers can be prevented, and early detection then becomes the goal. Self-skin checks should be considered, especially for those who have any risk factors for the disease. Some people who have significant risk factors or genetic syndromes associated with a higher risk may want to consider regular visits with their dermatologist.

Irritated skin can be caused by a variety of factors. These include immune system disorders, medications, and infections. When an allergen is responsible for triggering an immune system response, then it is an allergic skin condition.

Atopic Dermatitis (Eczema)
Eczema is the most common skin condition, especially in children. It affects one in five infants but only around one in fifty adults. It is now thought to be due to “leakiness” of the skin barrier, which causes it to dry out and become prone to irritation and inflammation by many environmental factors. Also, some people with eczema have a food sensitivity which can make eczema symptoms worse. In about half of patients with severe atopic dermatitis, the disease is due to the inheritance of a faulty gene in their skin called filaggrin. Unlike with urticaria (hives), the itch of eczema is not only caused by histamine so anti-histamines may not control the symptoms. Eczema is often linked with asthma, allergic rhinitis (hay fever) or food allergy. This order of progression is called the atopic march.

Allergic Contact Dermatitis
Allergic contact dermatitis occurs when your skin comes in direct contact with an allergen. For instance, if you have a nickel allergy and your skin comes in contact with jewelry made with even a very small amount of nickel, you may develop red, bumpy, scaly, itchy or swollen skin at the point of contact.

Coming in contact with poison ivy, poison oak and poison sumac can also cause allergic contact dermatitis. The red, itchy rash is caused by an oily coating covering these plants. The allergic reaction can come from actually touching them, or by touching clothing, pets or even gardening tools that have come in contact with the oil.

Urticaria (Hives)
Hives are an inflammation of the skin triggered when the immune system releases histamine. This causes small blood vessels to leak, which leads to swelling in the skin. Swelling in deep layers of the skin is called angioedema. There are two kinds of urticaria, acute and chronic. Acute urticaria occurs at times after eating a particular food or coming in contact with a particular trigger. It can also be triggered by non-allergic causes such as heat or exercise, as well as medications, foods, insect bites or infections. Chronic urticaria is rarely caused by specific triggers and so allergy tests are usually not helpful. Chronic urticaria can last for many months or years. Although they are often uncomfortable and sometimes painful, hives are not contagious.

Angioedema
Angioedema is swelling in the deep layers of the skin. It is often seen together with urticaria (hives). Angioedema many times occurs in soft tissues such as the eyelids, mouth or genitals. Angioedema is called "acute" if the condition lasts only a short time such as minutes to hours. Acute angioedema is commonly caused by an allergic reaction to medications or foods. Chronic recurrent angioedema is when the condition returns over a long period of time. It typically does not have an identifiable cause.

Hereditary angioedema (HAE)
Hereditary angioedema (HAE) is a rare, but serious genetic condition involving swelling in various body parts including the hands, feet, face, intestinal wall and airways. It does not respond to treatment with antihistamines or adrenaline so it is important to go see a specialist.

Skin conditions are one of the most common forms of allergy treated and managed by an allergist/immunologist, a physician with specialized training and expertise to accurately diagnose your condition and provide relief for your symptoms.

Sickle cell anemia is an inherited form of anemia — a condition in which there aren't enough healthy red blood cells to carry adequate oxygen throughout your body.

Normally, your red blood cells are flexible and round, moving easily through your blood vessels. In sickle cell anemia, the red blood cells become rigid and sticky and are shaped like sickles or crescent moons. These irregularly shaped cells can get stuck in small blood vessels, which can slow or block blood flow and oxygen to parts of the body.

There's no cure for most people with sickle cell anemia. But treatments can relieve pain and help prevent problems associated with the disease.

Symptoms
Signs and symptoms of sickle cell anemia, which vary from person to person and change over time, include:

Anemia. Sickle cells break apart easily and die, leaving you without enough red blood cells. Red blood cells usually live for about 120 days before they need to be replaced. But sickle cells usually die in 10 to 20 days, leaving a shortage of red blood cells (anemia).

Without enough red blood cells, your body can't get the oxygen it needs to feel energized, causing fatigue.

Episodes of pain. Periodic episodes of pain, called crises, are a major symptom of sickle cell anemia. Pain develops when sickle-shaped red blood cells block blood flow through tiny blood vessels to your chest, abdomen, and joints. Pain can also occur in your bones.

The pain varies in intensity and can last for a few hours to a few weeks. Some people have only a few pain episodes. Others have a dozen or more crises a year. If a crisis is severe enough, you might need to be hospitalized.

Some adolescents and adults with sickle cell anemia also have chronic pain, which can result from bone and joint damage, ulcers and other causes.

Painful swelling of hands and feet. The swelling is caused by sickle-shaped red blood cells blocking blood flow to the hands and feet.
Frequent infections. Sickle cells can damage an organ that fights infection (spleen), leaving you more vulnerable to infections. Doctors commonly give infants and children with sickle cell anemia vaccinations and antibiotics to prevent potentially life-threatening infections, such as pneumonia.
Delayed growth. Red blood cells provide your body with the oxygen and nutrients you need for growth. A shortage of healthy red blood cells can slow growth in infants and children and delay puberty in teenagers.
Vision problems. Tiny blood vessels that supply your eyes may become plugged with sickle cells. This can damage the retina — the portion of the eye that processes visual images, leading to vision problems.
When to see a doctor
Although sickle cell anemia is usually diagnosed in infancy, if you or your child develops any of the following problems, see your doctor right away or seek emergency medical care:

Unexplained episodes of severe pain, such as pain in the abdomen, chest, bones or joints.
Swelling in the hands or feet.
Abdominal swelling, especially if the area is tender to the touch.
Fever. People with sickle cell anemia have an increased risk of infection, and fever can be the first sign of an infection.
Pale skin or nail beds.
Yellow tint to the skin or whites of the eyes.
Signs or symptoms of a stroke. If you notice one-sided paralysis or weakness in the face, arms or legs; confusion; trouble walking or talking; sudden vision problems or unexplained numbness; or a headache, call 911 or your local emergency number right away.
Causes
Sickle cell anemia is caused by a mutation in the gene that tells your body to make the red, iron-rich compound that gives blood its red color (hemoglobin). Hemoglobin allows red blood cells to carry oxygen from your lungs to all parts of your body. In sickle cell anemia, the abnormal hemoglobin causes red blood cells to become rigid, sticky and misshapen.

The sickle cell gene is passed from generation to generation in a pattern of inheritance called autosomal recessive inheritance. This means that both the mother and the father must pass on the defective form of the gene for a child to be affected.

If only one parent passes the sickle cell gene to the child, that child will have the sickle cell trait. With one normal hemoglobin gene and one defective form of the gene, people with the sickle cell trait make both normal hemoglobin and sickle cell hemoglobin. Their blood might contain some sickle cells, but they generally don't have symptoms. But they are carriers of the disease, which means they can pass the gene to their children.

Risk factors
For a baby to be born with sickle cell anemia, both parents must carry a sickle cell gene.
Complications
Sickle cell anemia can lead to a host of complications, including:

Stroke. A stroke can occur if sickle cells block blood flow to an area of your brain. Signs of a stroke include seizures, weakness or numbness of your arms and legs, sudden speech difficulties, and loss of consciousness. If your baby or child has any of these signs and symptoms, seek medical treatment immediately. A stroke can be fatal.
Acute chest syndrome. This life-threatening complication causes chest pain, fever and difficulty breathing. Acute chest syndrome can be caused by a lung infection or by sickle cells blocking blood vessels in your lungs. It might require emergency medical treatment with antibiotics and other treatments.
Pulmonary hypertension. People with sickle cell anemia can develop high blood pressure in their lungs (pulmonary hypertension). This complication usually affects adults rather than children. Shortness of breath and fatigue are common symptoms of this condition, which can be fatal.
Organ damage. Sickle cells that block blood flow through blood vessels immediately deprive the affected organ of blood and oxygen. In sickle cell anemia, blood is also chronically low on oxygen. Chronic deprivation of oxygen-rich blood can damage nerves and organs in your body, including your kidneys, liver, and spleen. Organ damage can be fatal.
Blindness. Sickle cells can block tiny blood vessels that supply your eyes. Over time, this can damage the portion of the eye that processes visual images (retina) and lead to blindness.
Leg ulcers. Sickle cell anemia can cause open sores, called ulcers, on your legs.
Gallstones. The breakdown of red blood cells produces a substance called bilirubin. A high level of bilirubin in your body can lead to gallstones.
Priapism. Men with sickle cell anemia can have painful, long-lasting erections, a condition called priapism. As occurs in other parts of the body, sickle cells can block the blood vessels in the penis. This can damage the penis and lead to impotence

What Can You Do About Sensitive Teeth?
If you pass on hot or cold drinks because you know they’ll make your teeth hurt, it may be time to talk to your dentist about the possibility that you have sensitive teeth.

Sometimes other things can aggravate them, too, like sweet and sour foods or even cold air.

To be able to treat these tooth twinges, it helps to know what might be behind them. Once you’ve nailed down the cause, you can find a solution.

Take Care of Your Tooth Enamel
That’s a hard, protective layer that helps your teeth deal with everything you put them through. When it’s gone, nerve endings that cause pain are exposed.

If you have sensitive teeth, it’s possible some of your enamel has worn away.

To prevent or put the brakes on that damage:

Don’t brush too hard. Do you clean your teeth with a heavy hand? You might be taking off more than just plaque. Side-to-side brushing right at the gum line can make your enamel go away faster. You should use a soft-bristled brush and work at a 45-degree angle to your gum to keep enamel clean and strong.

Avoid acidic foods and drinks. Soda, sticky candy, high-sugar carbs -- all of these treats attack enamel. Instead, snack on:

Fiber-rich fruits and vegetables
Cheese
Milk
Plain yogurt
These will moisten your mouth and help fight acid and bacteria that can eat away at your teeth. Saliva is one way your mouth deals with them.

You can also drink green or black tea or chew sugarless gum. If you do eat something acidic, don’t rush to brush. Wait an hour or so to strengthen before you scrub.

Unclench your teeth. Over time, teeth grinding wears away your enamel. Sometimes, addressing your stress can stop the problem. If that doesn’t work, your dentist can fit you for a splint or a mouth guard.

If the problem is severe, you may need dental work to change your teeth’s position, or a muscle relaxant.

Take a break from bleaching. The quest for pearly whites may cause your pain. Thankfully, sensitivity from bleaching is usually temporary. Talk to your dentist about how the treatment might be affecting you, and whether you should continue it.

Get to the Root of the Problem
Sometimes, tooth sensitivity can be a sign of other issues, like:

Naturally shrinking gums. If you’re over 40, it could be that your gums are showing signs of wear and tear by pulling away from your teeth and uncovering your tooth roots. Those roots don’t have enamel to protect them, so they’re much more sensitive than the rest of your tooth.

Tell your dentist if your gums look like they’re receding. It can be a sign of other problems, like gum disease. Serious cases may need a gum graft. That moves tissue from somewhere else to cover the bare area.

Gum disease. Plaque and tartar buildup on your teeth can make your gums pull back. Sometimes, disease can set in. It can destroy the bony support of your tooth. Don’t smoke. It can lead to gum disease. To treat it, your dentist may do a deep clean of your teeth, called planing or scaling, that scrapes tartar and plaque below the gum line. You could also need medication or surgery to fix the problem.

A cracked tooth or filling: When you break a tooth, the crack can go all the way down to your root. You’ll notice pain when your tooth is cold. How your dentist fixes the crack depends on how deep it goes. If it’s a small crack that ends before your gums start, your dentist can fill it. If it’s below your gum line, your tooth will have to be pulled.

Treatment
Once you’ve found the problem, there are things your dentist can use to help ease your pain, including:

Toothpaste for sensitive teeth
Fluoride gel
Fillings that cover exposed roots
Sealants
Desensitizing pastes (not used with a toothbrush) you can get from your dentist
Mouthguard to protect teeth if you grind
If your case is serious, your dentist might suggest a root canal.

It’s also important not to shy away from dental care because of tooth pain. Ignoring your teeth can make things worse. Brush and floss twice a day to help keep your smile bright and pain-free. And see your dentist for a checkup twice a year.