Why is Allergy Present More Now than in Past? Hygiene vs Hapten Hypothesis

It is pretty much well-established fact that there are more people with food and inhalant allergy now than in the past. Two main theories have been proposed to try and explain this unfortunate phenomenon that is affecting more kids with each new generation.

Keep in mind the explanations provided below are significantly simplified for lay public understanding. One can go into cytokines, Th1 and Th2 responses, and other techno-jargon, but not here.

Perhaps the most popular explanation is the "Hygiene Hypothesis" which mainly states that major improvements in public health and medical technology have led to a cleaner home environment with less infectious and parasitic disease burden, resulting in less stimulation of the immune system and a consequent predisposition to allergic disease.

This hypothesis helps to explain why 3rd world nations which have poor sanitation and greater microbial/parasitic diseases do not suffer nearly as much allergic problems as well-developed nations. Basically, the dirtier and more disease ridden people grow up in, the less allergies they have because the immune system is preoccupied with fighting "real" infectious problems. In the absence of such immune stimulation, the immune system essentially gets "bored" and starts treating normal things like pollen as an infection that needs to be eliminated.

The alternative explanation is the "Hapten Hypothesis." Before explaining further how this theory works, first a little immunology instruction. Haptens are very small molecules which are able to easily pass through skin and mucus membranes with ease and by themselves cause absolutely no problems whether immune or allergy. However, when such haptens attach to a carrier protein, it may elicit a profound allergic immune response. Keep in mind that the carrier protein itself may also not elicit an immune response. It is the combination of hapten and carrier protein together that causes the problem.

According to the Hapten Hypothesis, persistent low-grade exposure to environmental haptens via the skin and oral routes at key times during human development – namely, pregnancy and the first year of life – can lead to allergy development. Dietary hapten intake may interfere with oral immune tolerance mechanisms while repeated skin exposure to haptens may promote elevated allergy responses.

What are some of these oral and skin haptens?

• Preservatives
• Nickel
• Cobalt
• Vanillin
• Pesticides
• Drugs (antibiotics and others)
• Industrial chemicals
• Food emulsifiers
• Food colorants
• Flavour enhancers
• Antioxidants
etc etc

Arguments promoting the Hapten Hypothesis over the Hygiene Hypothesis goes as follows:

#1. The biggest reduction in infections came at the end of the 19th century with improvements in sanitation and nutrition – not in the second half of the 20th century, when the greatest increase in allergic disease began – so why didn't they occur together??? However, significant exposure of haptens to the human population on a recurrent basis occurred on a major scale during the 20th century.

#2. The Hygiene Hypothesis states that our immune system does not get stimulated enough by infections. But technically, that's not true... Vaccination programs are the deliberate exposure of our immune system to a whole host of diseases including polio, tetanus, diphtheria, and measles, all by the age of 1 year. Disease burden is not a factor according to the Hapten Hypothesis.

#3. Studies have repeatedly shown that respiratory infections are associated with the development of allergic disease... but according to the Hygiene Hypothesis, the opposite should occur. According to the Hapten Hypothesis, drugs like antibiotics are haptens and can actually promote allergy development.

So is there a definitive answer here?

Unfortunately not, though there are very smart people working on this.

My hunch is that the final answer may be a combination of both hypothesis.

At the very least, there really may be something to the organic movement which promotes eating/drinking foods that contain no pesticides, preservatives, or chemicals and the use of skin products which also contain only "organic" ingredients.

However, keep in mind that the BIGGEST impact towards the prevention of allergy development are actions taken while a woman is pregnant through the infant's first year of life. After that, interventions may be too little, too late according to the Hapten Hypothesis.

I personally like the Environmental Working Group website to check if certain products are "organic" or not because I certainly don't have the time to check every consumer product myself.

When it comes to food, try to make all baby food from scratch. Next best would be to purchase baby food that is sold refrigerated (avoid baby food sold on regular shelves).

References:
Does hapten exposure predispose to atopic disease? The hapten-atopy hypothesis. Trends Immunol. 2009 Feb;30(2):67-74. doi: 10.1016/j.it.2008.11.006. Epub 2009 Jan 8.

Food-provoked eczema: A hypothesis on the possible role of systemic contact allergy to haptens present in both cosmetics and foods. Estetol Med Kosmetol 2011; 1(1): 35-40. DOI: http://dx.doi.org/10.14320/EMK.2011.006

The importance of hapten-protein complex formation in the development of drug allergy. Current Opinion in Allergy and Clinical Immunology 2014 Jun 17;

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FDA Approves Ragwitek... Ragweed Allergy Tablet by Mouth (Instead of Allergy Shots)

The FDA formally approved Ragwitek, the third new sublingual allergy tablet to be sold in the United States this year that works the same way allergy shots do... but instead is dissolved under the tongue at home instead of a shot in the arm in a medical office. Ragwitek is the first sublingual allergy tablet to treat ragweed. Although Oralair and Grastek are two other sublingual tablets that have already been approved by the FDA, they treat grass allergies rather than ragweed.

Ragwitek is a tablet made by Merck and treats patients aged 18-65 years who are allergic to only short ragweed. Ragwitek has a simple regimen of 1 sublingual tablet daily starting 12 weeks before the ragweed season and continued until the end of the ragweed pollen season. As with Oralair and Grastek, the first dose is given in a medical office to ensure safety with all other doses are taken at home. The tablet dissolves in less than 10 seconds.

Although in next few weeks US physicians should be able to start prescribing Ragwitek, treatment needs to actually begin in early summer thru the fall for full effectiveness.

As with Oralair and Grastek, epipen needs to be available at home due to possible risk of anaphylaxis. As with allergy shots, patients on beta-blockers for high blood pressure are not eligible to undergo this treatment.

The wholesale price of both Grastek and Ragwitek will be $8.25 per pill, or $247.50 for a 30-day supply. The wholesale price of Oralair will be $10 per pill, or $300 for a 30-day supply.

Sources:
FDA approves Ragwitek for short ragweed pollen allergies. FDA 4/17/14

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FDA Approves Grastek... Grass Allergy Tablet by Mouth (Instead of Allergy Shots)

Today, the FDA formally approved Grastek, the second new sublingual allergy tablet to be sold in the United States that works the same way allergy shots do... but instead is dissolved under the tongue at home instead of a shot in the arm in a medical office. Although this tablet has been available in Europe for some time, only now has sale/distribution in the United States been allowed under prescription.

Just 2 weeks ago, FDA approved Oralair which also treats grass allergies.

Grastek (aka Grazax in Europe) is a tablet made by ALK-Abello and Merck and treats patients aged 5-65 years who are allergic to only Timothy Grass. Grastek has a simple regimen of 1 sublingual tablet daily starting 12 weeks before and continued until the end of the grass pollen season. As with Oralair, the first dose is given in a medical office to ensure safety with all other doses are taken at home. The tablet dissolves in less than 10 seconds.

Although in next few weeks US physicians should be able to start prescribing Oralair, it really won't do much good for this year's grass allergies because in order for this tablet to be fully effective in the treatment of grass pollen allergies, treatment needs to actually begin in December but no later than January and continue through August. Grass pollen season begins in April/May, so for at least this year, it may be too late.

For both Oralair and Grastek, epipen needs to be available at home due to possible risk of anaphylaxis. As with allergy shots, patients on beta-blockers for high blood pressure are not eligible to undergo this treatment.

Sources:
Merck's grass pollen allergy drug wins U.S. approval. Reuters 4.14.14

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FDA Approves Oralair... Grass Allergy Tablet by Mouth (Instead of Allergy Shots)

Today, the FDA formally approved Oralair, the first new sublingual allergy tablet to be sold in the United States that works the same way allergy shots do... but instead is dissolved under the tongue at home instead of a shot in the arm in a medical office. Although this tablet has been available in Europe for some time, only now has sale/distribution in the United States been allowed under prescription.

Oralair is made by a French pharmaceutical company Stallergenes (Greer is US distributor partner) and treats patients aged 10-65 years who are allergic to 5 different grasses: Sweet Vernal, Orchard, Perennial Rye, Timothy, and Kentucky Blue Grass. Treatment is composed of a buildup and maintenance phase. Starting 4 months prior to the grass pollen season, a 100 IR tablet is administered under the tongue in a medical office to ensure no significant side effects. At home on day 2, two 100 IR tablets are administered. On day three and daily thereafter, a 300 IR tablet is placed under the tongue until the end of the grass pollen season. The tablets take about 1 minute to dissolve.

Although in next few weeks US physicians should be able to start prescribing Oralair, it really won't do much good for this year's grass allergies because in order for this tablet to be fully effective in the treatment of grass pollen allergies, treatment needs to actually begin in December but no later than January and continue through August. Grass pollen season begins in April/May, so for at least this year, it may be too late.

Another grass tablet will soon receive FDA approval called Grastek (aka Grazax in Europe). This tablet is made by ALK-Abello and Merck and treats patients aged 5-65 years who are allergic to only Timothy Grass. Grastek has a simpler regimen of 1 sublingual tablet daily starting 12 weeks before and continued until the end of the grass pollen season. As with Oralair, the first dose is given in a medical office to ensure safety with all other doses are taken at home. The tablet dissolves in less than 10 seconds.

For both tablets, epipen needs to be available at home due to possible risk of anaphylaxis. As with allergy shots, patients on beta-blockers for high blood pressure are not eligible to undergo this treatment.

Sources:
Stallergenes wins U.S. go-ahead for Oralair allergy pill. Reuters 4/2/14

Grastek Recommended by FDA Panel for Timothy Grass Allergy. Medscape 12/12/13

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New Ragweed Under the Tongue Pill Instead of Allergy Shots Recommended by FDA Panel

Yesterday, the FDA Allergenic Products Advisory Committee supported approval for a new sublingual allergy tablets (Ragwitek) that work the same way allergy shots do... but instead is dissolved under the tongue at home instead of a shot in the arm in a medical office. Given this is only a panel recommendation, final "official" FDA approval may not occur for another year or so for sale/distribution under prescription in the United States.

Ragwitek is made by ALK-Abello and Merck and treats patients aged 18-65 years who are allergic to only short ragweed pollen. The way Ragwitek is taken is placement of 1 sublingual tablet daily starting 12 weeks before and continued until the end of the ragweed pollen season. The first dose is given in a medical office to ensure safety with all other doses taken at home. The tablet dissolves in less than 10 seconds.

Epipen needs to be available at home due to possible risk of anaphylaxis. As with allergy shots, patients on beta-blockers for high blood pressure are not eligible to undergo this treatment.

Ragwitek is similar to Oralair and Grastek which treat only grass allergy. Oralair and Grastek were both recommended by the FDA panel last year.

Source:
Sublingual Ragwitek Backed FDA Panel for Ragweed Allergy. Medscape 1/28/14

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Two New Sublingual Allergy Tablets Approved by FDA Advisory Committee

This week, the FDA Allergenic Products Advisory Committee unanimously supported approval for two new sublingual allergy tablets (Oralair and Grastek) that work the same way allergy shots do... but instead is dissolved under the tongue at home instead of a shot in the arm in a medical office. Although both tablets have been available in Europe for some time, final "official" FDA approval may not occur until end of 2014 (or later) for sale/distribution under prescription in the United States.

Oralair is made by a French pharmaceutical company Stallergenes and treats patients aged 10-65 years who are allergic to 5 different grasses: Sweet Vernal, Orchard, Perennial Rye, Timothy, and Kentucky Blue Grass. Treatment is composed of a buildup and maintenance phase. Starting 4 months prior to the grass pollen season, a 100 IR tablet is administered under the tongue in a medical office to ensure no significant side effects. At home on day 2, two 100 IR tablets are administered. On day three and daily thereafter, a 300 IR tablet is placed under the tongue until the end of the grass pollen season. The tablets take about 1 minute to dissolve.

Grastek (aka Grazax in Europe) is made by ALK-Abello and Merck and treats patients aged 5-65 years who are allergic to only Timothy Grass. Grastek has a simpler regimen of 1 sublingual tablet daily starting 12 weeks before and continued until the end of the grass pollen season. As with Oralair, the first dose is given in a medical office to ensure safety with all other doses are taken at home. The tablet dissolves in less than 10 seconds.

For both tablets, epipen needs to be available at home due to possible risk of anaphylaxis. As with allergy shots, patients on beta-blockers for high blood pressure are not eligible to undergo this treatment.

Sources:
Grastek Recommended by FDA Panel for Timothy Grass Allergy. Medscape 12/12/13

Sublingual Oralair Recommended for Grass Pollen Allergy. Medscape 12/11/13

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Allergy Sufferers also Have More Severe Migraines

Many people suffer from migraines. Many people also suffer from allergies. What may have been suspected but is now clarified is that those individuals who suffer from BOTH allergies and migraines have much more frequent and severe headaches than those who do not have allergies. [link]

Based on a survey response from 5,849 patients who suffer from migraines, over two-thirds also suffered from allergies. From this group, researchers found that the odds of experiencing more frequent headaches for individuals with allergies and migraines were 33 percent greater than those suffering from migraines without allergies.

When patients were further subdivided based on the type of allergy they had (allergic, non-allergic, or both), those who suffered from both allergic and non-allergic had the most frequent and severe headaches.

Although there appears to be an association between allergies and migraine severity, the question now becomes whether the migraines themselves increase sino-nasal symptoms OR does the sino-nasal symptoms of allergies aggravate or trigger the migraine.

Based on a prior study, it is known that migraine patients under 45 years with allergies who received allergy shots had 52% less frequent and severe headaches than those who did not receive allergy shots. As such, it may be worthwhile to aggressively treat any sino-nasal symptoms in patients who suffer from migraine headaches. Such treatment may involve not just medications, but even surgery if anatomic trigger points are seen.

References:
Chronic rhinitis and its association with headache frequency and disability in persons with migraine: Results of the American Migraine Prevalence and Prevention (AMPP) Study. Cephalalgia. Published online before print November 25, 2013, doi: 10.1177/0333102413512031

Allergy and immunotherapy: are they related to migraine headache? Headache. 2011 Jan;51(1):8-20. doi: 10.1111/j.1526-4610.2010.01792.x. Epub 2010 Nov 4.

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Aspirin Allergy and Desensitization Protocols

For patients who suffer from terrible allergies, asthma, nasal polyps, and also suffer an allergy to aspirin, desensitization to aspirin can profoundly improve overall allergies and airway hyper-reactivity through an as yet unknown mechanism. It is hypothesized that aspirin desensitization works by decreasing leukotriene production and downregulating cystienyl leukotriene receptors resulting in a decrease in histamine and tryptase release from mast cells which causes allergy symptoms.

However, there are two problems regarding patients who wish to pursue aspirin desensitization: not many physicians perform it due to risk of life-threatening anaphylaxis and lack of standardized protocols.

Here are some sample published protocols for aspirin desensitization. Keep in mind that regardless of which protocol is administered, the aspirin desensitized state only exists as long as regular aspirin continues to be taken. If the patient forgets to take aspirin for a few days (typically 48 hours), the protocol has to be repeated.

Protocol #1:
Aspirin dissolved in water at 1mg/cc concentration. On day 1, patient is given 10mg, 30mg, 60mg, and 100mg of aspirin spaced 6 hours apart. On day 2, an additional 100mg, 150mg, and 300mg is given spaced 8 hours apart. The patient is discharged home on 300mg or 350mg of aspirin to be taken twice a day as well as zantac 150mg twice a day for GI prophylaxis. If needed, proton pump inhibitors can also be taken.

Protocol #2:
Aspirin is administered at intervals of 10–30 min in the following dosages: 0.1 mg, 0.3 mg, 1 mg, 3 mg, 10 mg, 30 mg, 40 mg, 81 mg, 162 mg, and 325mg. The dilution and dosing may be altered depending on the patient's clinical situation.

Protocol #3:
Aspirin is administered starting at 1 mg and doubling each dose every 30 min up to a final dose of 100 mg (therefore lasting 3.5 hours).

Protocol #4:
Aspirin given in 5 sequential doses of 5, 10, 20, 40, and 75 mg given every 30 minutes (the protocol lasting 2.5 hours).

Depending on the physician, patient's clinical characteristics, and comfort level of all concerned, these protocols may be performed in an office-setting to even in the intensive care unit of a hospital.

Pre-treatment with anti-histamines, singulair, or systemic steroids may or may not be administered. Beta-blockers typically is stopped 24 hours prior to protocol initiation. Monitoring during the protocol include blood pressure, pulse, and peak expiratory flow measurements every 30 min as well as checking for any reactions involving the skin, nose, eye, or breathing. Once the protocol is completed, monitoring is continued for an additional 3-6 hours.

Keep in mind that our office does not perform aspirin desensitization and provides this information for educational purposes. Please contact your local allergist to determine if they perform aspirin desensitization. Your best bet is your closest tertiary care academic medical center as locations where such protocols are performed.

Trivia: When a patient suffers from asthma, nasal polyps, and aspirin allergy, it is known as Samter's triad.

References:
Hypersensitivity to ASA in patients with coronary artery disease: rapid desensitisation is feasible. European Society of Cardiology Council. E-journal of Cardiology Practice 3.

Selection of patients for ASA desensitization treatment. J Allergy Clin Immunol 118: 801–804.

Rapid oral challenge-desensitisation for patients with ASA-related urticariaangioedema. J Allergy Clin Immunol 105: 997–1001.

Rational approach to aspirin dosing during oral challenges and desensitization of patients with aspirin-exacerbated respiratory disease. J Allergy Clin Immunol. 2009 Feb;123(2):406-10. doi: 10.1016/j.jaci.2008.09.048. Epub 2008 Dec 3.

Selection of aspirin dosages for aspirin desensitization treatment in patients with aspirin-exacerbated respiratory disease. J Allergy Clin Immunol. 2007 Jan;119(1):157-64. Epub 2006 Nov 13.

ASA sensitivity: the role for ASA challenge and desensitisation in postmyocardial infarction patients. Cardiology 91: 8–13.

Rapid desensitisation procedure for patients with ASA hypersensitivity undergoing coronary stenting. Am J Cardiol 95: 509–510.

Aspirin Hypersensitivity and Desensitization Protocols. Ther Adv in Drug Safe. 2011;2(6):263-270.

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Local Anesthetic Allergy

Rarely, a patient presents with a history of being allergic to lidocaine or another kind of local anesthetic. Often, the "allergic" reaction described (racing heart, light-headed, dizziness, etc) is more attributable to the epinephrine which is often used in conjunction with the anesthetic; therefore not a true allergy, but a not unexpected possible side effect.

Also, if a true allergy is present, it may not be to the anesthetic itself, but the preservative contained within, typically metabisulfite and/or methylparaben. The exception are single-dose vials which are preservative-free, unless they contain epinephrine. Any local anesthetic containing epinephrine, whether a single-dose or multi-dose vial, has metabisulfite in it. The preservative in the multi-dose vial of lidocaine and other anesthetics typically contain methylparaben. As such, the muti-dose vial of lidocaine with epinephrine would contain both metabisulfite and methylparaben.

In any case, if a true allergy to the anesthetic itself is present, there is the possibility that another type of anesthetic can be used. Why?

There are two different classes of local anesthetics divided into amino esters and amino amides. Chemically, amino amides have an amide link between the intermediate chain and the aromatic end, whereas amino esters have an ester link between the intermediate chain and the aromatic end.

Amino Ester

Amino Amide

There are other differences. Pharmacologically, amino esters are metabolized in the plasma whereas amino amides are metabolized in the liver. Amino esters are unstable in solution, but amino amides are very stable in solution.

Amino esters are also much more likely than amino amides to cause allergic hypersensitivity reactions.

Amino Esters (only one "i" in the spelling of the name):

• Cocaine
• Procaine
• Tetracaine (in the form of cetacaine)*
• Chloroprocaine*
• Benzocaine (in the form of cetacaine)*
• Cetacaine (benzocaine and tetracaine)*
• Propoxycaine

Amino Amides (two "i"'s in the spelling of the name):

• Lidocaine*
• Mepivacaine*
• Prilocaine
• Bupivacaine*
• Ropivacaine*
• Levobupivacaine
• Articaine
• Etidocaine
• Trimecaine
• EMLA (lidocaine/prilocaine)

* is next to those commonly carried in hospitals.

Much appreciate the assistance of Margaret Rowe, PharmD who helped write this blog article.

Source:
Local Anesthetics. Emedicine 4/19/13

Local Anesthetic. Wikipedia

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What are the Most Common Severe Drug-Induced Anaphylaxis?

Image by James Heilman, MD from Wikipedia

Interesting paper came out listing the most common severe drug-induced anaphylaxis. From a database of 333 patients who suffered from anaphylaxis,

• Anaphylactic shock (76.6%)
• Severe systemic reactions (10.5%)
• Acute laryngeal edema (9%)
• Severe bronchospasm (2.1%)
• Fatal in 6 cases (1.8%)

There were 270 cases (81.1%) of ambulatory anaphylaxis. Sixty-three cases (18.9%) occurred during anesthesia.

84 drugs were identified as being responsible for these cases of anaphylaxis.

• Antibiotics (49.6%)
• Muscle relaxants, latex and anesthetics (15%)
• NSAIDS (10.2%)
• Tylenol (3.9%)
• Iodinated or magnetic resonance imaging contrast media (4.2%)
• Allergy shots and vaccines (3.9%)
• Other drugs (13%)

Among antibiotics, amoxicillin (97 cases), other penicillins (four cases), cephalosporins (41 cases), quinolones (15 cases), and pristinamycin (seven cases) were the most common.

Reference:
Severe drug-induced anaphylaxis: analysis of 333 cases recorded by the Allergy Vigilance Network from 2002 to 2010. Allergy. 2013 Jun 6. doi: 10.1111/all.12168. [Epub ahead of print]

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At Home Allergy Testing

Recently, a new at-home allergy test can be found on store shelves throughout the United States as well as Amazon.com. It is called "MyAllergyTest" produced by ImmuneTech Corporation and it is FDA approved. The way it works is that you place a few drops of blood into the collection kit which is than mailed to a lab in a pre-paid, pre-addressed envelope.

Results are than obtained via internet or by certified mail in about one week.

What's tested? Only ten things (IgE only):

• Timothy Grass
• Bermuda Grass
• Mountain Cedar
• Short Ragweed
• Alternaria Mold
• Cat Dander
• Mite pternoyssinus
• Egg White
• Wheat
• Milk

As such, if testing comes back normal, it does not mean you do not have allergies... It just means that you do not have allergies to these 10 things only... You could be allergic to other non-tested substances.

A report is produced listing what you are allergic to and how badly:

How accurate is the testing? Apparently, it is comparable to Pharmacia CAP system (specific IgE FEIA).

In terms of actual numbers, the test has a sensitivity 88%, specificity 94%, and accuracy 91%.



Source:
FDA.gov

Company Website

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How Does Neuropathy Lead to Lump in Throat or Phlegmy Throat Sensation?

To preface, have you ever been to the dentist and received a novacaine injection prior to a dental procedure? Did you notice that where the injection is performed, it feels as if the area feels really swollen and also you feel like you are drooling... but than when you look in the mirror, there's no drooling and there's no swelling either?

In this dental situation where novacaine got injected leading to a temporary induced neuropathy...  a similar phenomenon can also occur in the throat region due to neuropathy most commonly triggered by a virus or throat-level reflux (LPR). This condition is called laryngeal sensory neuropathy (LSN).

And because the neuropathy occurs in the throat region... a sensation of swollen or lump feeling in the throat (globus) may occur just like the sensation in the face/jaw after getting numbed up for a dental procedure.

Similarly, a mucus phlegmy throat sensation may also occur just like a drooling sensation of the face/jaw after being injected with novacaine.

Such a swollen throat or phlegmy throat sensation can also be temporarily induced in normal patients when the throat gets numbed up with lidocaine or other anesthetic for a surgical procedure.

How is this condition treated?

First and foremost, other non-neurologic etiologies must first be ruled out with medications and extensive testing. Also, triggers that may have led to this neuropathy must be thoroughly addressed as well. Such testing may include allergy testing, specific food avoidance, 24 hour multichannel pH impedance, manometry, etc, etc.

SELSAP is a promising test to evaluate for laryngeal sensory neuropathy.

Once laryngeal sensory neuropathy is confirmed, medications like amitriptyline, neurontin, and tramadol can be tried.

For more information, click here for globus and here for phlegmy throat.

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How is a Pollen Forecast Made?

Pollen Trap from Burkard

Unlike weather forecasting which utilizes high technology, satellites, complex computer models, etc, pollen forecasting seems downright archaic, though just can be just as complex and unpredictable.

So, here's what happens...

The main "equipment" to enable pollen forecasting is a simple air trap in order to capture and ultimately count what pollen is currently circulating in the environment. This equipment known as a "Volumetric Spore Trap" is placed in an open area and sucks in a specific volume of air through a narrow slit. Within the spore trap is a rotating drum covered with sticky tape upon which pollen gets stuck on.

Spore Trap. Image from Burkard

Every morning, an aerobiologist removes the sticky tape and places it on a glass slide to look at it under 400x magnification.

Pollen spores are identified and counted by the aerobiologist.

Based on this pollen count information in combination with the weather forecast, precipitation, wind direction, etc a pollen forecast can be provided for a region.

However, a pollen forecast may not accurately reflect local conditions. For example, grass counts may be very elevated all year round where timothy grass is present as feed for horses whereas regional pollen forecast may show elevated grass pollen only during the summer.

More obviously, mold spores would be elevated inside a damp old home all year round that is not reflected in a regional pollen forecast.

In any case, allergies can be treated with medications.

   

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What's That Yellow Pollen Coating My Car Windows?

Every spring, a yellow coating of pollen covers everything, most noticeably car windows. For many people with allergies, this yellow pollen is the cause of all their sinus and nasal misery triggering bouts of sneezing, sniffling, water eyes, etc.

However, this yellow pollen produced by pine trees is NOT a significant allergy trigger. When it comes to allergy, the biggest culprits are the pollen you can not see. Such springtime microscopic pollen that IS the culprit for allergies come from trees (non-pine) and grasses.

So don't demonize the yellow pollen! Unless, of course, you are upset that the car now needs to be washed/cleaned.

If you are curious what you may be allergic to, you can get allergy tested. Or, try an over-the-counter anti-histamine, many of which used to be prescriptions.

Here's a complete list of allergy medications and how they work.

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Kim Kardashian Gets Allergy Testing

Celebrity Kim Kardashian of Keeping up with the Kardashians reality TV show underwent allergy testing with Dr. Mirmelli. Allergy testing was accomplished via skin prick (our office performs allergy testing by blood draw instead called immunocap).

She apparently was allergic to her pet cat...

Kim apparently decided to let her pet cat Mercy go... a decision in contrast to what most cat-allergic people do.

Watch the video.

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Does Acupuncture Help With Allergies?

Image from Acupuncture For All

According to one study, it does... Performed by researchers in China and Korea, they divided 238 patients suffering from allergies into 3 groups: active acupuncture, sham acupuncture, and no treatment.

They found that acupuncture, even if it was sham, did help significantly with nasal allergies. However, only active acupuncture helped with not just nasal allergies but also allergy symptoms beyond the nose!

Of course, when considering all the other research performed on this subject, the results are a bit more mixed with some reporting no improvement with acupuncture.

For those interested in avoiding medications and allergy shots, it may be something to consider trying. It can't hurt and it can potentially even help.

References:
A multicenter, randomized, controlled trial testing the effects of acupuncture on allergic rhinitis. European Journal of Allergy and Clinical Immunology. Volume 68, Issue 3, pages 365–374, March 2013

Acupuncture for allergic rhinitis: a systematic review. Annals of Allergy, Asthma & Immunology Volume 102, Issue 4 , Pages 269-279, April 2009

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Another Egg-Free Flu Vaccine Approved by FDA

First there was Flucelvax introduced in 2012 and now there is Flublock, both considered egg-free for those concerned with egg allergy in traditional flu vaccines.

Rather than being cultured in eggs, Flucelvax is cultured in mammalian cells and Flublock is grown in caterpillar cells injected by an insect virus containing the flu gene.

Both vaccines are approved for use in people 18 years and older.

Why the concern of egg-allergic patients with the traditional flu vaccine used to defend against both seasonal and pandemic flu virus?

Traditionally, the flu shot vaccine (both H1N1 and seasonal) are grown inside eggs which is where this concern arises. It also doesn't help that the pre-flu shot questionnaire specifically asks about egg allergy. Though egg-based, during vaccine production the egg protein is filtered out such that there should be no egg contaminants in the final vaccine. However, it is theoretically possible that some egg may still be present in the vaccine.

Although there is an infinitesimal possibility of egg contaminants, studies have shown that even patients with life-threatening egg allergy can still safely have the flu vaccine.

In spite of these reassurances, there are still concerns from patients and healthcare professionals which makes the availability of two different egg-free flu vaccines welcome news.

Source:
FDA approves next-generation, bug-based flu vaccine. MSNBC 1/16/13

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Egg Free Flu Vaccine Approved by FDA

Why the concern of egg-allergic patients with the flu vaccine used to defend against both seasonal and pandemic flu virus?

Traditionally, the flu shot vaccine (both H1N1 and seasonal) are grown inside eggs which is where this concern arises. It also doesn't help that the pre-flu shot questionnaire specifically asks about egg allergy. Though egg-based, during vaccine production the egg protein is filtered out such that there should be no egg contaminants in the final vaccine. However, it is theoretically possible that some egg may still be present in the vaccine.

Although there is an infinitesimal possibility of egg contaminants, studies have shown that even patients with life-threatening egg allergy can still safely have the flu vaccine.

In spite of these reassurances, there are still concerns from patients and healthcare professionals.

As such, there is now a new FDA-approved flu vaccine called Flucelvax which is guaranteed to be egg-free. Rather than being cultured in eggs, this vaccine is cultured in mammalian cells.

Downside is that latex-allergic patients are unable to safely receive this vaccine.

Made by Novartis, this vaccine is approved for use in people 18 years and older.

For more info.

Source:
FDA approves first seasonal influenza vaccine manufactured using cell culture technology. FDA 11/20/12

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Is Flu Shot Safe for Patients With Egg Allergy?

It is the season for flu shots... and with that... we invariably get phone calls from patients asking whether it is safe to receive the flu shot if they are egg allergic. Generally speaking, the blunt answer is that it is safe... even if you have a life-threatening egg allergy.

Why the concern? The flu shot vaccine (both H1N1 and seasonal) are grown inside eggs which is where this concern arises. It also doesn't help that the pre-flu shot questionnaire specifically asks about egg allergy. Though egg-based, during vaccine production the egg protein is filtered out such that there should be no egg contaminants in the final vaccine. However, it is theoretically possible that some egg may still be present in the vaccine.

Given the infinitesimal possibility of egg contaminants, is the concern still legitimate?

There has been a recent study by Canadian researchers who followed 367 egg-allergic people, mostly children, who got the flu shot over five years. Almost one-third of these patients had a significant history of anaphylaxis after eating eggs causing serious symptoms like trouble breathing or a drop in blood pressure. However, in this study, NOT ONE of those patients, experienced a serious reaction to the flu vaccine. Only 13 of the 367 had mild "allergy-like" symptoms, like itchy skin or hives, within a day of the shot.

Furthermore, numerous past studies that involved close to 4,000 egg-allergic people who got the flu shot revealed not a single case of a serious allergic reaction.

However, if such studies still do not alleviate anaphylaxis concern if egg-allergic...

You can either get one of the new completely egg-free flu vaccine Flucelvax or Flublock or...

To play it safe, the absolute safest way for a patient with egg allergy to get the flu shot is via a few steps:

1) Get a test dose of the flu vaccine where a small amount (0.025cc typically) of the flu vaccine is administered sub-dermally.
2) Wait 10-20 minutes.
3) If there's no reaction (redness and swelling of the skin), get the shot properly into the muscle.
4) If there's a large wheal reaction, it's probably best not to get the flu shot or see an allergist to get desensitized prior to receiving the injection.
5) If flu shot given, make patient wait 30 minutes to observe for any adverse reaction.

Not all practices may be familiar with these particular steps. If that's the case, request to take the flu vaccine to an allergy office (including ours), and have us administer it. (Please note that we do not provide egg desensitization.)

If you are only IgG allergic and not IgE allergic to egg, no need to worry. Get the flu shot.

For a more in depth discussion, click here to read a document prepared by the American Academy of Allergy Asthma & Immunology.

Reference:
Egg-allergic patients can be safely vaccinated against influenza. Journal of Allergy and Immunology. In Press. Published Online Oct 1, 2012

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Why Can't Some Contact Dermatitis Be Diagnosed by Blood Test, EVER?

I often see patients for allergies who desire allergy testing due to mysterious hive-like rash on the skin, and given many are fearful of needles, they opt for a blood test like RAST or immunoCAP to diagnose what they are allergic to. Some would even argue that skin prick testing would not be diagnostic.

Though such blood tests have become remarkably accurate (skin prick is still the most accurate way to diagnose what a person is allergic to), there are profound and significant limitations.

In order to understand why, first a little biology lesson.

In "classic" allergy (Type 1 hypersensitivity), there are antibodies called IgE floating around in the blood. When such antibodies come into contact with what a person is allergic to, it causes mast cells to explode releasing bioactive chemicals that triggers the classic signs of allergy including runny nose, sneezing, and hives.

The timing of exposure to reaction is very short... within minutes.

In this scenario, the allergy blood testing is appropriate... because such testing measures the amount of IgE antibodies floating around in the blood.

Unfortunately, not all contact dermatitis is due to this biologic response.

There is another type of allergic reaction that can cause skin manifestations that is NOT mediated by IgE antibodies at all!

Known as Type 4 Hypersensitivity, special cells called macrophages initiate the "allergic" reaction when it detects an allergic substance.

This type of reaction occurs hours to days AFTER exposure.

Obtaining a blood test for allergies will NOT diagnose this type of allergic reaction because the test measures the level of IgE which is not involved in this type of reaction!

The ONLY way to test for Type 4 Hypersensitivity is skin patch testing, typically performed by dermatologists.

Patch testing is performed on skin where the dermatitis is not apparent (typically upper back). The allergens are mixed with a non-allergic material (base) to a suitable concentration which is then placed in direct contact with the skin within small aluminium discs. Adhesive tape is used to fix them in place. The patches are left in place for 48 hours. The patches should not be exposed to sunlight or other sources of ultraviolet (UV) light. After 48 hours the patches are removed and an initial reading is taken one hour later. The final reading is taken a further 48 hours later. Additional readings beyond 48 hours increase the chance of a positive test patch by 34 per cent. The patient should refrain from washing until the last reading is taken.

Some chemicals produce an allergic reaction only when exposed to light (usually ultraviolet type A). If this scenario is suspected, patch testing is performed, one while exposed to UVA light and the other hidden in darkness. A positive light-reaction is made if the patch exposed to UVA light causes a skin reaction whereas the one hidden in darkness looks fine.

What are some common chemicals/substances that cause Type 4 skin reactions?

• Balsam of Peru: an aromatic mixture made from resins and essential oils. It is found in the haemorrhoid preparation Anusol, some perfumes and certain spices. 
• Caine mix: local anaesthetics found in preparations for sore throats, sunburn remedies, haemorrhoid preparations, Wasp-eze. Used by dentists and doctors for minor surgical procedures. 
• Carba mix: rubber 'accelerators' (chemicals used to speed up the polymerisation process in the manufacture of rubber). It is found in rubber gloves, shoes, bandages and elastic. Of those allergice to carba, 85 per cent are also allergic to thiuram. 
• Chlorocresol: a substituted phenol preservative that kills bacteria. It is widely used in medications and some cosmetics. It cross-reacts with Dettol, which you should also avoid if you have a chlorocresol allergy. 
• Chromate: a metal used for plating other metals to prevent rusting and in the manufacture of stainless steel. It is also found in cement and tanned leather. 
• Cobalt: found in jewellery, dental implants, artificial joints, jet engines. Most patients are also allergic to nickel, and some are also allergic to chromate. 
• Colophony: present in adhesives, plasters, paper, printing inks, medicated creams, glue tackifiers (stamps, labels), and cosmetics. 
• Epoxy resin: plastics, used mainly as adhesives in the industrial setting but also by DIY enthusiasts. Found in two-component glues, such as Araldite. 
• Formaldehyde: preservative frequently used in household products and in industry. Often found in cosmetics and shampoo. 
• Fragrance mix: used in patch testing, this collection of eight individual fragrances detects about 75 per cent of patients allergic to perfume. If you have perfume allergy, you will not be allergic to all fragrances, but you cannot tell from the label which fragranced cosmetics are safe. Avoid all cosmetics listing 'parfum' as an ingredient on the label. Also found in air fresheners, washing powders and candles. 
• Lanolin: produced by sheep to protect the fleece from the results of weathering. It is widely used in cosmetics, medical creams and bandages. 
• Latex: most commonly found in gloves used by healthcare professionals.
• Mercapto mix/thiazoles: a rubber accelerator found in rubber shoes, insoles, gloves and elastic. It is also a component of balloons and bandages. 
• MBT (mercaptobenzothiazole): another rubber accelerator. Neomycin: an antibiotic commonly used in ear and eye drops and creams to treat infected skin problems. Cross-reacts with other antibiotics. 
• Nickel: 10 per cent of women and at least 1 per cent of men are affected by nickel allergy. Nickel is released from metals such as alloys or electroplated items. Found in jewellery, keys, coins, zips and buckles, pacemakers and batteries. 
• Parabens: preservatives found in cosmetics and topical medical products to inhibit the growth of fungi and prevent slow deterioration. They are commonly used in cosmetics, household products, glue, shoe polish, shampoos and conditioners, sunscreens and medical creams. 
• PPD (paraphenylenediamine): a permanent hair dye that is very frequently used in hair salons and at home. Dyed hair cannot cause an allergy but the dye may do during application. Also found in skin paints, such as 'henna' tattoos, and occasionally in fur and leather dyes. Primin: a substance produced by the plant Primula obconica, a common houseplant. 
• PTBPF resin (para-tertiary-butylphenol-formaldehyde): a synthetic polymer used as an adhesive. It is often combined with leather or rubber to make shoes, handbags, watchstraps, hats and belts. 
• Thiuram (tetramethylthiuram disulphide or TMTD): another rubber accelerator that is also found in pesticides. People who are carba allergic often react to thiuram. Patients who react to the drug disulfiram (Antabuse), used for alcohol dependence, may also be allergic to thiuram. 
• Toluene sulphonamide formaldehyde resin (TSF resin): the commonest polymer in nail polish and a frequent allergen.

Given a patient often has no idea why, how, when a hive reaction occurs, it is important to obtain a good history to see if a reaction is immediate or delayed as it may influence what type of allergy testing may be required.

BUT, the key thing for people to remember is that allergy blood testing and skin prick testing can NOT diagnose all allergies due to intrinsic factors.

Skin patch testing may be the ONLY test to determine what that mysterious hive reaction is due to.

AND, now you know why!

For physicians, skin patch testing supplies can be purchased at www.dormer.com. However, your local dermatologist should be able to perform such patch testing (our office does not).

In our area, Dr. Moshell at Georgetown is the expert in this field.

Phone: 301-951-2400
5530 Wisconsin Ave, Suite 730
Chevy Chase, MD 20815

Another dermatologist in Northern Virginia who performs patch testing is:

Kurt Maggio, MD
7512 Gardner Park Dr
Gainesville, VA 20155
Phone: 703-753-9860

Robert Gurney, MD
11315 Sunset Hills Rd
Reston, VA 20190
Phone: 703-437-7744

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