If you’re an allergy patient or doctor managing allergies, you will likely come across situations where there is a discrepancy between the suspected allergens and skin test results. While this can be frustrating for both patients and doctors alike, it is important to understand why such discrepancies can occur, in order to make sure your patient receives the best possible care and treatment. In this blog post, we’ll discuss some of the potential reasons as to why negative skin testing results might not match a patient’s diagnosis or symptoms. We’ll also look at how to interpret these test results more accurately when they don’t reflect expected outcomes.
From Reddit–>This is a real patient comment and a real patient concern: My allergist told me to use Dymista nasal spray until allergy testing. However, I googled it and found out that Dymista should be stopped 5 days before allergy testing. In my allergy test, dust mites came back negative but I don’t believe it. I have obvious symptoms of dust mite allergy and I want to get allergy shots as soon as possible, before my allergies get worse and start ruining my life.
Should I find another allergist for allergy testing and allergy shots? Because my allergist made the mistake of prescribing me Dymista before my allergy test so I got false negatives on my skin and blood tests.
Credit to Reddit to find out what people really think and can join together to make changes in their daily lives. Anyone doubt that after GameStop and AMC? I have some concerns, however, with using Reddit as your source of medical information. Let’s take the issue of using Dymista prior to skin testing. Dymista indeed has antihistamines (azelastine) as well as topical corticosteroids and it recommended to stop this spray 3-5 days before skin testing. Topical antihistamines do not have the potency of ORAL antihistamines, and often the topical sprays with antihistamine do not interfere with the testing. How do you know for sure if Dymista has interfered with testing results? One of the quality controls I always use is a histamine control and saline control when testing for allergy. The positive histamine control should always be positive and the saline negative, guaranteeing accurate testing.
“I have been to so many allergist and my skin tests are all negative. I cannot believe this is true. Why has not anyone found a way to fix this? Patients will even have a seasonal pattern to other allergy symptoms.”
You can feel the frustration of negative allergy testing, when clinical symptoms of allergy are so present. I myself have to explain why testing is negative when patients sneeze and cough during the pollen seasons of Spring & Fall. Here’s some insight into negative allergy testing with VERY positive clinical symptoms of allergy.
- I wish our memories were 100%–it would be obvious if we messed up and took antihistamines or nasal sprays too close to testing and caused false negative allergy results. As mentioned previously, I can generally tell when skin testing is “suppressed” by comparing a positive histamine with negative saline prick testing. They should be wildly different.
- There is a condition called local allergic rhinitis that occurs when all skin testing and blood testing for allergy is negative, but the body still responds right in the nose. My problem is getting treatment for local allergic rhinitis in a convenient cost-effective manner. Of course it is neither cost effective nor pleasant to have your allergist blow dust mite in your nose and record nasal congestion on a scale of 1-10– how would you like to do that?
- You may not have IgE-mediated allergy as the cause of your symptoms. Believe it or not, not everybody has allergy in the sense of hypersensitivity that responds to allergy shots. Sometimes the culprit is an irritant such as dust, fumes, cigarette smoke, aerosols, all of which will cause “allergy” symptoms, but no positive skin tests.
- Another strategy I will use for negative skin testing is to confirm results with blood tests. This is direct measurement of IgE and fortunately, is not suppressed by any medication you take, including antihistamines.
So here’s the conundrum–>Allergy symptoms, but no positive tests? ENTER Local Allergic Rhinitis. Simply put, LAR is allergy that’s limited to the nose, and not in the skin or blood, making skin testing/blood testing very unfruitful for diagnosis.
In order to perform testing to measure local allergic rhinitis, the clinician must by the equipment to perform nasal challenges and develop protocols that are only suited for research hospitals. (at least for now) Medical literature has been published regarding diagnosis and treatment of LAR, but not in the United States which always means an additional hurdle is the FDA.
- I’ll summarize some published articles on LAR for those of you who want to know more.
- Allergy symptoms are very common, up to 30% of the general population. No wonder everyone thinks they have allergy.
- In Europe, allergists are using AIT (allergy immunotherapy) for treatment of LAR and it works! Knowing that dust mite accounts for 60% of local allergic rhinitis, it’s a very reasonable strategy to use dust mites and pollens in allergy extracts for LAR.
- BTW, the article below is written by the guru or AIT, Dr. “Hal” Nelson; if nothing else, read the article to catch up on the latest in allergy shots.
- And now for the “meat” of LAR–published by Dr. Campo who is the leading author for LAR diagnosis and treatment. Now you’ll understand why only 30% of rhinitis patients have IgE-mediated allergy. Fortunately, treatment is still available for LAR.
- The second article in this block is also a review of LAR. It is interesting that despite adequate research on local allergic rhinitis, treatment and diagnosis of this condition hasn’t caught on here in the States. Perhaps the more we talk about it, the better treatment will evolve.
If you are having allergy symptoms, but tests come back negative, it is still possible that you have Local Allergic Rhinitis. Now during the winter months, you are not going to have the typical sneezing postnasal drainage and coughing that you get during the spring or fall–but that does not mean you do not have allergy to dust mite. Treatment is available and can help improve your quality of life. If you find yourself experiencing symptoms of allergy but cannot get your allergist to diagnose allergic rhinitis, you may be dealing with local allergic rhinitis. Call us today @ 918-495-2636 and get your allergies controlled.