Medical & Vocabulary: "Hives" & Allergy

My Arm

Almost a year ago, 31st August, 2010, I suffered from heat rash after running under hot sun, I applied corticosteroid cream and I was fine. Yesterday, after I had had my shower, I sat in front of the computer and started feeling itchy in my buttocks. It got more and more itchy but I didn't realise what happened. Until at one point, I had to go to the toilet and I was shocked at the rash that was everywhere on my backside!!! Immediately I thought, it must be the mites on my chair, otherwise, why would it start only on my butt, so I quickly went to dilute some Dettol and wiped the infected areas.

After another hour, it spread down to my thighs, down to the knee caps, and slightly up my back. It became increasingly itchy and red and I found it difficult not to scratch.

My thigh

I tried to sleep anyway but when I got up, rash had covered my entire back and even up to the arms. I was afraid that it would spread to my face, and so I had to do something. I tried to apply some corticosteroid cream that was left from last time on my right arm to test the result, and after a short while, the rash had disappeared, so I applied it to everywhere I could see rash, and waited. Luckily, I was almost fine again before I left home to work. Took less than 2 hours to recover from the visual symptoms. (Although it is occasionally coming back in certain areas.)

What really happened I don't know. I was playing football in the rain yesterday on a muddy field in Happy Valley yesterday, and so were my students. I had shower in the public bathroom. I ate McDonald's for dinner. Which one of these could have caused the rash?

What kind of rash was it?

After a little research, I think this time, "Hives" is the most likely suspect. Medically, it is called Urticaria,
Hives is a common name in both English and Chinese speaking countries, meaning, the home of bees (beehive).

Beehive
Image from i.zdnet.com

The cause of urticaria is often unknown, and it could well be allergy (food or medication), reaction to temperature changes, the sun, contact with poisonous plants, autoimmune, etc.

For my case, unless I'm allergic to McDonald's fast food or I took medicine which I don't know, all others seem likely. But I'm starting to think that mine is heavy-sport induced, just like heat rash I got last time. In fact, every time I have finished some sport, I do get some smaller ones on my arms, but not as serious as this one.

I don't like to take any kind of medication, I like to strengthen my body by making its immune system do more work and rely less on medicine, but I can't possibly go to work with hives all over my body. No choice.

Talking about allergy, a friend of mine told me that she is severely allergic to kiwifruit, and I found that quite surprising, so I went to find the answer, and from Wikipedia, the most informative paragraph is this one:

Kiwifruit
Image from bbcgoodfood.com

"Raw kiwifruit is also rich in the protein-dissolving enzyme actinidin, (in the same family of thiol proteases aspapain), which is commercially useful as a meat tenderizer, but can be an allergen for some individuals. Specifically, people allergic to latex, papayas or pineapples are likely to also be allergic to kiwifruit. The fruit also contains calcium oxalate crystals in the form of raphides. Reactions to these chemicals include sweating, tingling and sore mouth or throat; swelling of the lips, tongue and face; rash; vomiting and abdominal pain, heartburn; and, in the most severe cases, breathing difficulties, wheezing and collapse. The most common symptoms are unpleasant itching and soreness of the mouth, with the most common severe symptom being wheezing. Severe symptoms are most likely to occur in young children."^[1]

Actinidain fruits: pineapple, mango, papaya

Never knew kiwifruits are so dangerous.

As mentioned above, "actinidain (or actinidin) is a type of cysteine protease enzyme found in fruits including kiwifruit (genus Actinidia), pineapple, mango and papaya. This enzyme is part of the papain-like peptidase C1 family.

It is an allergen and commercially useful as a meat tenderizer."^[2]

In some cases of severe allergic reactions, anaphylactic shock might occur ^[3], causing low blood pressure and inability to breath.

Is it that serious? Well, in House M.D. Season 5 episode House Divided, there is one episode when Dr. Chase went "into anaphylactic shock while taking a body shot from a stripper wearing strawberry body butter during his bachelor party."^[4]

Anaphylaxis can be deadly! And one of the symptoms of anaphylaxis includes hives!! I better keep myself checked today because the symptoms can develop over minutes to hours.^[3]

Resources:
Medical & Vocabulary : Heat Rash and Bug Bites @ Locky's English Playground
http://lockyep.blogspot.com/2010/08/medical-vocabulary-heat-rash-and-bug.html

[1] http://en.wikipedia.org/wiki/Kiwifruit#Nutrition
[2] http://en.wikipedia.org/wiki/Actinidin
[3] http://en.wikipedia.org/wiki/Anaphylactic_shock#Anaphylactic_shock
[4] http://en.wikipedia.org/wiki/Dr._Robert_Chase
http://en.wikipedia.org/wiki/House_Divided

Anaphylactic Shock @ YouTube
http://www.youtube.com/watch?v=TZBLaDXa6pE