Inflammation and rash at site of injury

So recently my dad has been having continuous flair ups of inflammation. If he gets a canker-sore, a bug bite, a scatch, or really anything, the site of contact will either become inflammed and swell up, or he'll get a rash. It's happened multiple times to his lip, eye, arm, and foot. He's a 53 year old male. He smokes and his diet mainly consists of red meat, with very few greens or carbs. He's gone to see an allergist but they ran tests and determined he wasn't allergic to anything. My mom and I are concerned that it might be autoimmune. Has anyone heard of anything like this? Any ideas of what it could be?

[Bhupinder Kaur, MD]

Hello,
It can be due to urticaria or hives. Hives (medically known as urticaria) are red, itchy, raised areas of skin that appear in varying shapes and sizes. They have a tendency to change size rapidly and to move around, disappearing in one place and reappearing in other places, often in a matter of hours.

Many cases of hives are "idiopathic," meaning no cause is known. Others may be triggered by viral infections or medications. Get it evaluated from a dermatologist and discuss this possibility with him for your husband.

It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.