You can tell a lot about a child by looking at their appendages – arms, elbows, legs and knees. The arms and legs are like canvases mapped out by various bruises, scrapes, bumps, bites and rashes. Of course, every mother can tell you a story behind each precious mark, each dramatic boo-boo.

But sometimes it's hard to distinguish between a bite, a rash, an allergic reaction or an ongoing skin problem that needs attention.

The most common skin problems in children are bug bites, scrapes, bruises and diaper rash in young children. Eczema and skin infections due to bacteria, viruses and fungi are also quite common, according to Dr. Mary Stone at the University of Iowa Division of Dermatology.

Insect Bites
What they look like: red bumps, clusters of bumps

"Insect bites usually appear in clusters or rows of three," says Dr. Ronald Glick, an osteopathic physician in Mesa, Ariz. "Think breakfast, lunch and dinner."

According to Dr. Glick, spider bites are the most common, as well as bites from mosquitoes and fleas. "Fleas can live in carpet for three months," he says.

Children are more likely to get bigger reactions to bug bites than adults and because they spend more time playing outdoors, they are more likely to get bitten, according to Dr. Stone.

Insect bites are painful, itchy, red and swollen bumps that can be treated with medicated creams, cool baths and antihistamines to relieve pain and itching.

Eczema and Atopic Dermatitis
What it looks like: circular or patchy areas that are inflamed, red, scaly

Atopic dermatitis, or eczema, is a very common, chronic or long-lasting disease that affects the skin. "Atopic" refers to diseases that are hereditary (run in families) and often occur together, like asthma and allergies. "Dermatitis" means inflammation of the skin.

"Eczema and atopic dermatitis are synonyms and often used as general terms for many types of dermatitis," says Dr. Glick. "Eczema is an immune-mediated response that occurs when the body is reacting to one or more anogens or a foreign substance."

Most often affecting infants and young children, eczema causes the skin to become inflamed and itchy, causing redness, scaling and cracking, and sometimes weeping and crusting.

The good news? Many children outgrow the symptoms by adulthood. Dr. Glick says there is a 50-percent chance that by adolescence the symptoms are gone.

"I had eczema really bad as a child and into high school, and my oldest daughter had it when she was very young," says Janese Ritter from Gilbert, Ariz. and mother to Cassidy and Hailey. "I outgrew it after high school, and Cass outgrew it even earlier."

According to the National Institute of Health (NIH), the cause of this skin disease is unknown, but appears to be caused by hereditary and environmental factors. Physical and emotional stress can worsen the condition.

In addition to atopic dermatitis, there are other categories of eczema. Contact eczema, according to the NIH, is when the skin has come into too much contact with an irritant (acid, cleaning agents, chemicals, fabrics, etc.). Allergic-contact eczema is when the skin comes into contact with a substance the immune system does not recognize and is a red, weepy reaction (i.e. poison ivy).

"There is also atopic eczema, which is common, where the child would have chapped cheeks, and the eczema is always symmetrical and increased in creases like elbows and knees," says Dr. Glick.

Topical steroids, over-the-counter like hydrocortizone or stronger prescription versions, have been the standard treatment, but Dr. Glick says there are new treatments called immuno-modulators, like Protopic and Elidel, that he likes. "In my opinion, Elidel is better because it can be used on thin skin without any significant side effects like burning, itching or flu-like symptoms," he says.

Robert Edwards, a Phoenix, Ariz. father of three, recommends keeping skin moisturized with Keri Lotion. "I had eczema when I was younger, and my oldest daughter has it now. Nothing works better than Keri Lotion."

Dr. Glick also recommends keeping moisturizers on the skin as well as avoiding the causes. If the causes are unknown, a pediatric allergist is a good place to look for answers.

Impetigo
What it looks like: honey-colored, crusty sores often on the face between the mouth and nose

Impetigo is a highly-contagious bacterial infection that is common in children and starts out as a small cut or scratch that gets infected. The spots or blisters rupture and crust over with a tan or yellowish crust and can be spread to other parts of the body and to other children or adults.

"Impetigo is caused by a staph or strep infection," says Dr. Glick. "Streptococcus is responsible for other things like strep throat."

According to the American Osteopathic Association, impetigo affects preschool and school-aged children, especially in the summer. To remove the crusts, soak the infected area in warm water for 20 minutes, scrub with a washcloth and antibacterial soap and then apply an antibiotic ointment.

Elaine Allison, center director for Children's World daycare in Gilbert, Ariz., says she has not seen cases of impetigo as much as when she was younger. "We take several precautions to help prevent the spread of infections," she says. "Using latex gloves, washing our hands and the children's regularly, cleaning with a bleach solution and posting health alerts as soon as we see something unusual are some of the steps we take to help prevent the spread of anything contagious."

Rashes
What is the most common rash in preschool-aged children? "Diaper rash," says Allison. "Children react to perfumes in the diaper or soaps in their bath water or after they have had diarrhea, and then we see a lot of diaper rash."

"Sometimes we see yeast infection along with diaper rash," says Dr. Glick. "In that case it's important to keep the skin dry and use an over-the-counter ointment like Lotramin."

How can you tell when a rash is minor, like a heat rash, that will go away or a rash that is a serious reaction needing treatment? "Look for a rapid change in the child's health," says Dr. Glick. "Is the child wheezing, lethargic? Other symptoms are high fever, changes in consciousness, or the child isn't urinating. In those cases, you should seek treatment immediately."

Sunburn
For Dr. Glick, the former president of the American Cancer Society in Mesa, Ariz., the single most common skin problem he sees in young children is sunburn. "Eighty percent of all skin cancer is caused by sunburns that occur before the age of 18," he says.

Dr. Glick recommends wearing protective clothing like hats, sunglasses, thick T-shirts and using waterproof sunblock every hour and a half with at least 15 SPF that also contains zinc or titanium dioxide. Brands like Vanicream can be found at the local drugstore.

If a child suffers a sunburn, Dr. Glick says to hydrate the skin, use Advil or baby aspirin and cool soaks.

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