Laptops and Leg Rash (Erythema ab igne)

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Laptops and Leg Rash (Erythema ab igne)

Post by rogerwimmer » Sun May 15, 2011 8:34 am

Doc: I know your wife is a dermatologist, so I'm writing to see if I can get some free advice. Please? Here is my question: I use my laptop several hours a day, and I usually have it resting on my lap (thighs). I guess that's why it's called a laptop. Anyway, over the past few weeks, I have developed a red rash on my legs where I have the laptop placed. It itches and doesn't look great. Does your wife know if the rash, or whatever it is, is caused by the laptop? Thanks in advance. - Anonymous

Anon: Yes, my wife (Darnell) is a dermatologist and I and showed your question to her. But before I get to what she said, I want to make sure that you are 100% clear in understanding that the following information is NOT a medical diagnosis. It is for informational purposes only and based only on your description of the problem. You should see a dermatologist who can tell you what's going on.

OK, with that caveat mentioned, here is a summary of the discussion Darnell and I had about your question . . .

Darnell: I would need to see this person to make an accurate diagnosis, but from the description in the note, I suspect that it might be erythema ab igne.

Me: Aretha has a big knee? How do you know the person's name? The person didn't include his or her name.

Darnell: No, erythema ab igne. Erythema (air-uh-THEME-uh) is Greek for "redness," "ab" is Latin for "from," and "igne" is Latin for "fire" or "heat." It's a skin condition caused by prolonged exposure to heat or an infrared source. Although the condition was identified many years ago with objects like hot water bottles and heating pads, a new "high tech" form was discovered a few years ago with laptop computers and is often called, "Laptop skin." The heat from the laptop on the person's legs is causing the irritation. By the way, there is an indication that skin cancer can occasionally occur in an area of erythema ab igne. So, it's air-uh-THEME-uh a big knee, or redness from heat.

Me: Why didn't you just say "redness from heat?" However, I think "Aretha Has a Big Knee" is better. Or, it could be shortened to "Aretha's Big Knee." (A strange look from Darnell.)

Darnell: Because that's what it's called. It's similar to what you say about students in your research classes when they ask you for the definition of "standard deviation" and you say it means, "average difference." They then ask, "Why didn't you just say that?" Because that's what it's called.

Well, OK then. I now have the basic information to pursue more "stuff" for you.

I read a few dozen articles about erythema ab igne (EAI) on the Internet and you should read a few yourself by clicking here.

I learned that EAI will generally clear up in a few weeks if you eliminate the heat source, so put your laptop on something, such as a laptop pad, to keep the heat off your thighs. And, as I mentioned, see a dermatologist to receive a proper diagnosis.

(Side note) There are about 30,000 skin, hair, and nail conditions and problems that dermatologists deal with on a regular basis. Yes, 30,000 . . . that is not an exaggerated number. Many of these conditions and problems have very strange sounding names and it's difficult for a non-dermatologist like me to remember them, so I make up my own terms. My wife and her derm buddies use me as their source of amusement when they hear my "new" terms. Here are two of the several terms I have invented:

Actinic keratosis, known as "AK" to dermatologists, is a rough, raised area on skin that has been exposed to the sun over a long period of time and some AKs may develop into a type of skin cancer. But I have a problem with the term actinic keratosis and I developed my own name for the condition. So . . . The condition is caused by too much exposure to the sun, or "baking" in the sun. AK? That's the two-letter designation for Alaska. Actinic keratosis? Nope. I call it Baked Alaska. That makes more sense to me.

And, in my opinion, here is one of the strangest dermatological terms - Bullous pemphigoid. What? Read that again . . . bullous pemphigoid. What the heck is that? Well, lemme tell ya. It is a skin disorder characterized by large blisters. Gag me. But Bullous Pemphigoid? I can't remember that, so I made up my own term. Ready for this? I call it Bulbous Pimple Groin, and I never have trouble remembering it. The next time you go to a dermatologist, ask him/her what Bulbous Pimple Groin is. I GUARANTEE you will get a very, very strange expression on the doctor's face.

Among many things, being married to a dermatologist is a language-enlightening experience. I amuse myself.

Get some type of laptop pad, or even one of the laptop cooling fans - click here.

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Roger Wimmer is owner of Wimmer Research and senior author of Mass Media Research: An Introduction, 10th Edition.

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