Indoor allergens during the winter

January 3rd, 2012

Although many pollen-allergic individuals may experience less allergy/asthma symptoms this time of the year, others may “peak” with symptoms and medication requirement. Indoor allergens (house dust mite, mold, animal danders) are often the cause of symptoms during late fall, winter, and early spring.
Environmental allergen exposure studies suggest that even when a pet is only intermittently indoors, dander levels are well above the symptom threshold for cat and dog allergens when the pet is not physically present. Such studies suggest that the dog who is confined only to the laundry room at night or the cat that never enters the bedroom will likely cause symptoms in sensitized individuals regardless of location.
House dust mite and indoor mold allergens are ubiquitous in westernized society (except at very high elevation… think Denver), though older and less-maintained homes certainly represent greater sources of exposure. In principle, sensitized individuals better tolerate indoor living when occupants regularly clean, implement appropriate dust mite reduction strategies, and maintain HVAC or other air filtration systems per manufacturer guidelines. Select studies have also demonstrated improvement in allergen levels using HEPA filtration systems in living areas. However, even heroic cleaning and maintenance programs often do not bring dust, mold, or animal dander levels below the symptom threshold for many people who have indoor allergies. Medical treatment and/or immunotherapy are excellent and proven options for such people.
Kevin Parks MD

Cold and flu season

December 20th, 2011

We are in the thick of it now.
So how many “colds” are too many? The answer is most definitely not the same for every person. An elementary school teacher or child who attends school (or has siblings who attend school) will have more frequent viral upper respiratory infections than an empty nester with an office job involving infrequent person to person contact. The average US grade school age child is exposed to 6-9 distinct upper respiratory viruses per cold and flu season. Most of these infections are mild, some even unrecognized by the child or a parent. Others may result in prolonged symptoms of coughing, nasal congestion, sore throat, low fevers, and occasionally gastrointestinal symptoms (i.e. adenovirus). The most common trigger for an asthma exacerbation in a child is a viral infection–the common cold virus being the primary culprit (rhinovirus). Although these viruses are similar each year, dozens of distinct strains exist around the world, resulting in incomplete immunity even after decades of exposures.
Some children progress from frequent viral upper respiratory infections to sinusitis, bronchitis, pneumonia, and otitis media (ear infections) more frequently than the average child. These children may need additional work up for immunodeficiency, allergies, asthma, adenoid hypertrophy, and (rarely) cystic fibrosis.
We often hear the complaint that despite a flu shot, “I get sick every year anyway!” You’re right! The flu shot only improves protection against influenza, which is one of MANY viruses that circulate in our community each season.
Do viruses have a protective effect in small children in terms of allergy and asthma onset? The jury is still out on this question, with significant ongoing investigation in basic and clinical science that should help us understand the answer in the near future. Some data suggest that early life viral infections may reduce the incidence of respiratory allergies. Other studies signal a specific increase in asthma onset due to a small handful of viruses if exposure occurs at key time points during infancy (especially rhinovirus, RSV, and possibly metapneumovirus). Stay tuned on this question!
Kevin Parks MD

Nasal saline irrigation

December 19th, 2011

Does it work for allergies?
The data are mixed, but one thing we do know… it can’t hurt. Or can it? A recent story hit major news outlets linking Neti Pot use to Primary Amoebic Meningoencephalitis (PAME), which can be fatal. 2 patients who used tap water in the Southern US (a key point) may have acquired the amoeba during nasal saline irrigation using a Neti Pot with tap water. Though unconfirmed, these would be the first documented cases of PAME via treated municipal water. The organism of concern, Naegleria fowleri, is typically acquired through recreational activity in natural water sources–usually lakes in the Southern US.  When I was  a resident at UNC Chapel Hill, we had one case of an unfortunate boy with PAME who passed away shortly after swimming in a local lake. The amoeba is typically introduced through forced water into the nose/sinuses (i.e. diving, water-skiing, etc.) in bodies of standing water.
Reasons this is unlikely in Southern Oregon:
1. Naegleria fowleri infection has not been documented as a result of participation in water sports in local lakes.
2. If you follow the instructions on your Neti Pot or Sinus Rinse bottle and use DISTILLED WATER, you can’t acquire the amoeba.
3. We have no community reports of any amoebic disease as a result of municipal water supplies in Southern Oregon. If you have a well, you should have it evaluated periodically for microorganisms and metal content.

The bottom line is, allergic rhinitis sufferers benefit from regular nasal saline irrigation using a buffered solution in conjunction with allergen avoidance strategies, appropriate use of medications, and allergen-specific immunotherapy in select cases. Talk to us about this at your next visit if have additional questions.
Kevin Parks MD

Is gluten evil?

November 23rd, 2011

The answer is clearly NOT the same for everyone!
First, what is gluten? This naturally-occurring protein is abundant in wheat, oats, rye, barley and a few other grains that most Americans consume regularly. As such, “gluten sensitivity” is a distinct phenomenon from wheat allergy. True food allergy has an immunologic basis and yields demonstrable food-specific allergic antibodies (IgE) via skin prick or APPROPRIATE blood tests (not all blood tests are equal–talk with your doctor before you decide how to proceed). In contrast, gluten sensitivity or celiac disease does not involve allergic antibodies. Typical manifestations of celiac disease include abdominal pain, cramping, diarrhea, failure to thrive in children, unintended weight loss in adults, and sometimes a distinct rash called dermatitis herpetiformis. Gluten sensitivity (not a true allergy) does NOT produce hives, respiratory symptoms, or systemic reactions (anaphylaxis). It is true that many symptoms of gluten sensitivity and food allergy overlap, i.e. nausea, abdominal pain, cramping, diarrhea, and bloating. For this reason, allergy testing to wheat, oats and other grains is sometimes useful. The gold standard test used to diagnose celiac disease is a small bowel biopsy (not easy to get), though serologies (blood test for anti-tissue transglutaminase and anti-endomysial antibodies) can also be suggestive of presence or absence of the disease.
Many patients have negative testing for celiac disease and food allergy but clearly feel better when they avoid large amounts of gluten. To what can we attribute this frequent observation? Well, food intolerance or “sensitivity” exists in many other forms as well, and we are certainly allowed to have gluten sensitivity without true celiac disease. I have also observed that individuals who are vigilant enough to limit or exclude gluten from their diet tend to observe other healthy habits that may impact their well being: better dietary choices, increase level of activity, and avoidance of other environmental exposures that may negatively impact their health (i.e. tobacco, allergens, irritants, and infections).
If you are concerned about gluten sensitivity or celiac disease, start with talking to your physician to decide whether additional testing is appropriate.
Kevin Parks MD

Egg allergy and influenza vaccine

November 23rd, 2011

New data have emerged regarding egg allergy and the flu shot. The influenza vaccine contains a small amount of ovalbumin (egg protein), which has always been the basis for concern in administering the flu vaccine to egg-allergic individuals. However, recent assays (lab tests) have been more precise in quantifying the actual amount of egg protein in each of the currently available vaccines, which is very small. As such, the risk of an allergic reaction for a person with egg allergy is smaller than previously estimated. The revised vaccine guidelines now recommend that, if a person experienced hives ONLY with egg exposures (i.e. eating eggs), the flu shot can appropriately be administered in the primary care setting (pediatrician, family doctor, etc.). If the reaction was anaphylaxis, the vaccine should be administered in an allergist’s office. We no longer recommend skin testing to the vaccine in most cases.
Kevin Parks MD

Medication Allergies

November 18th, 2011

Many patients and referring providers have questions about reactions to medications… a rash, a headache, a twitchy eyebrow–what is an allergic reaction to a medication??
The term “allergy” is used colloquially to describe an adverse reaction. Such a reaction may, in fact, be predictable based on the pharmacologic action of the drug (i.e. lightheadedness if a blood pressure medication is lowering blood pressure too much);may be a known possible side effect (i.e. constipation due to a narcotic pain medication); or may be idiosyncratic (i.e. a headache due to an allergy nose spray). However, true allergic reactions to medications have an immunologic basis and cause symptoms that are consistent with an immunologic process. The classic example is penicillin allergy causing hives, though many other forms of allergic drug reactions can occur–possibly involving every organ system from skin to lungs to nephritis or pancreatitis.
Most drug reactions/allergies are diagnosed based on history–the course of events that occurs after taking the medication. Sometimes blood tests or other diagnostic information surrounding the reaction are helpful in making the diagnosis. We are able to test for a LIMITED number of medications via skin/blood tests for true immunologically-mediated reactions. We sometimes employ other diagnostic or treatment procedures to better determine whether a medication is safe to take. These procedures include GRADED DRUG CHALLENGES or DRUG DESENSITIZATION. We can only determine whether testing is necessary or possible after reviewing the history, medical records, and need for possible future treatment with the drug in question.

Kevin Parks MD

How do pollen counts work?

April 19th, 2011

Most pollen counts are obtained using a volumetric device–a method by which number of pollen grains (or mold spores) are measured in a defined volume of air. At our office, we use a Rotorod system, which captures grains on a small rod that spins at a known rate at a defined interval. The pollen is transferred to a microscope slide, then grains are counted and categorized by our research coordinator (Andrea) as trees, grasses, or weeds. Although we are able to differentiate species based on pollen grain morphology (appearance under the microscope), we typically report the counts as a category rather than a species.
When grass season starts, the slide comes to life with beautiful oval grains that sometimes fill the entire microscopic field!
Pollen counts on other websites are typically made at other physical sites, i.e. Eugene, Portland, or Bend. We are currently the only pollen counting site in Southern Oregon. We make our counts available to news outlets (Channel 12 KDRV 6pm news) and tweet/post online (see front page of this site).

Kevin Parks MD

Spring pollen 2011

April 19th, 2011

As you can see by our pollen counts, the weather is a key factor influencing anemophilous (wind pollinating) plants in the Rogue Valley. So far, our spring has been wetter than average, and tree pollen has been significant during the few “sunny” and windy days since February. In years past, we’ve observed large grass counts after wet early spring seasons, but time and weather will tell how big the upcoming grass season will be… but it will come! Check out Facebook or Twitter feeds on the lower right side of our front page for daily pollen counts through weed season (mid summer).

Kevin Parks MD