Test for allergen returns troubling result for reader
BY KEITH ROACH, M.D.
DEAR DR. ROACH: I am 62 and in excellent health. I had a blood test for allergens, including honeybees and wasps. My results ranged from moderate to high levels. However, the test for serum proteins, IgE levels, concerns me even more: The reference range is less than 430 ug/L, and my result came back as 2,955 ug/L. While I do have an appointment to see a specialist, it is quite some time away. I have not been stung for years. It would appear that there is something else going on. Should I be concerned? I have never had a skin rash, and I don’t have any allergies, except for stinging insects. — P.M.
ANSWER: There are five classes of immunoglobulins (antibodies), and IgE is associated with allergies. IgE levels often are high in people with allergies, including allergic dermatitis and asthma.
I wouldn’t have ordered the total IgE level while testing for allergy to hymenoptera (stinging insects), but now that you know about this very high level, I am concerned about it. Your history doesn’t suggest a lot of allergies, so it’s worth considering some of the other causes. Although there are at least 30 different diagnoses I could find, the three that I want to mention are parasitic diseases, hyperimmunoglobulin E syndrome and IgE myeloma.
Of the parasites, the two most common in most of the U.S. and Canada are Ascaris and Strongyloides (both roundworms). There are specific blood tests to look for them. Given your lack of symptoms, nothing may need to be done, but it would give you an answer for having this very high IgE level. A search for other parasites may be appropriate, based on your travel history.
Hyperimmunoglobulin E syndrome is a genetic disorder, usually showing up in childhood with skin rashes and infections. People with this disorder have a particular facial appearance. I don’t think you have this.
IgE myeloma is a rare blood cancer, where the abnormal antibody cells make IgE. Other blood diseases, including lymphoma, are worth considering.
Your level is high enough that I would recommend that you get a more thorough evaluation, even though it may be due to allergies.
DEAR DR. ROACH: What, if any, is the difference between a “TIA” and a “ministroke”? I have since pressed my neurologist on the issue, and he said, “A TIA is an event you are aware that you are having; ministrokes are events you are not aware of at the time; they are only identified by an MRI.” This made some sense to me, but I have never seen the distinction elsewhere. All the websites I read called the two terms synonymous. Do you agree with my neurologist? — Anon.
ANSWER: The term “ministroke” is misleading, and I don’t use it.
The difference between a stroke and a transient ischemic attack is that in a TIA, the brain tissue recovers, usually within 24 hours, while a stroke is a permanent loss of brain tissue. The brain has the ability to recover function in some cases, as different parts of the brain can take over the function of the part of the brain that was damaged.
A stroke can be “silent,” with no perceptible loss of function to the person experiencing it, or it can cause any level of disability from mild to catastrophic. Your neurologist is referring to clinically silent strokes when he talks about ministrokes.
Both TIA and strokes call for an urgent assessment of how to reduce risk of a further, potentially devastating event. This includes lifestyle changes (smoking, alcohol, exercise, diet, stress), control of any predisposing conditions (such as high blood pressure and diabetes, if present), and sometimes medication, such as aspirin or clopidogrel (Plavix).