If you have an unexplainable rash, researchers say an iPad could be to blame.

It's not uncommon to go out to dinner or shopping and see a child playing on an iPad. Maxine Terry says her 3-year-old grandson can even use one. "My granddaughter Aryana and her little brother, they are constantly on them. They carry them with them everywhere. They have them at dinner sometimes," she said.

Terry says for the most part, her grandkids keep their iPads in a protective case, but not always. "Ary uses hers more in her lap, whereas my grandson uses his more in front of him or propped up on a table. He's managing it that way so it’s not touching his skin as much," she said.

A July report in the Journal of Pediatrics found an 11-year-old boy treated at a San Diego hospital for an itchy body rash that couldn't be helped with usual treatment. Doctors traced the cause to the boy's daily use of his iPad.

It turns out the boy is allergic to nickel, a metal that can cause an allergic reaction. "It's caused by direct contact on the skin, especially places where it may rub or be sweaty," says Dr. Luella Guzman.

Doctors tested the boy's iPad and found a chemical compound found in nickel in the iPad's outside coating.

Pediatrician Luella Guzman says if your child is allergic to nickel, they can get a rash. "It's usually red, itchy, really itchy. Kids will often scratch it to the point that they start to get little blisters, and the blisters may break and get crusty," she said.

We learned once you figure out your child has a nickel allergy, it's usually easy to treat. "To treat it, we avoid it. The second thing is to put hydrocortisone ointment or cream on it that you can get over the counter. It doesn't have to be anything fancy or prescribed," adds Dr. Guzman.

Maxine says after hearing about this case she will watch her grandchildren more closely when they use iPads. "I would be more cautious, and I would definitely talk to my daughter and let her know to maybe do some research," she said.

Recently-published studies found nickel allergies can be caused by a variety of electronic devices, including laptops and cell phones.

Apple had no comment when asked whether all iPad models and other Apple devices contain nickel.

Doctors said the boy got better after simply putting a protective case on his iPad.