2008
Welcome to my first attempt ‘blogging’. My daughter and her husband have been doing this for years and it has been most enjoyable. I thought it may have some utility as a supplement to my clinical practice of allergy/clinical immunology. Here goes……..
FAST FORWARD
2023 —
And that was how this began. That young lady is now 15 years old.
The case of Fenugreek
Up until a week ago, I had never heard of fenugreek. On my first day back at Riley to start the 2009 new year, I had a young man, just under 2 years of age who presented with concerns about reactions to legumes. The list of suspects included peas, green beans, black beans, baked beans, and lentils. The mother also shared with me that during breast feeding she used ‘fenugreek’. This product is used to help nursing mothers. In our discussion, the mother brought up the concern that the fenugreek may have contributed to the legume reactions.
I had not heard of ‘fenugreek’ prior to this. I have been involved with allergy long enough to know that any food product ingested by mankind for as long as we have been on the planet has been implicated in an allergic response. I wanted to know more about this ‘fenugreek’.
I consulted my online food ‘Allergy Advisor’ regarding fenugreek and got a wealth of information to get me started. To my surprise later that week the Journal of Allergy and Clinical Immunology (JACI) had an article from a group in Norway regarding fenugreek.
Fenugreek (aka Greek hay, Greek fennel, Bird’s foot, Greek hay-seed) is a legume. It is used as a flavoring in many foods including curry, blends of spice, and even tea. As an herbal medication it has been touted as being helpful in initiating and maintaining milk production. There are references for its use in diabetes and hypertension. Importantly, it is a legume and many legumes share certain proteins and may be cross-reactive in some patients.
The purpose of the JACI article was to evaluate the allergenicity and antigenicity of the proteins in fenugreek. There were 29 patients in the study who had specific IgE antibodies to legumes, peanut, soy, pea, lupin, and fenugreek. These patients ranged from 1 to 53 years of age. High levels of antibody to both peanut and fenugreek were found in most patients and the sensitization to fenugreek was believed to be due to cross-reactivity in those patients with peanut allergy. In this study, the reactivity to the other legumes was weaker. Here the other legumes (specifically peanut) were implicated in causing sensitization to fenugreek. With the young lad that I saw I wondered if there is the possibility that the fenugreek may have worked in the opposite direction – fenugreek exposure causing sensitization to the other legumes.
I was not aware of this association: fenugreek and peanut. In my clinic notes I debated about doing the peanut test since he had no exposure, but since he reacted to a large number of the other legumes I had the skin test placed. His response was positive to peanut.
The world of IgE-mediated reactions to foods is growing significantly. Our diets are changing with significantly more opportunities for ingredients in foods from other lands becoming part of our lives. Herbal supplements may contain a variety of items that could lead to sensitization. It is important to inquire about the use of such products.
This morning after finishing the Sunday paper, I browsed through one of my recent pediatric journals Contemporary Pediatrics Volume 26 . I was attracted to the ‘Your Voice’ article by Dr. Amar Dave of Ottawa, Ill titled above, the sad loss of the patient history. I applaud Dr. Dave for the comments. The issue so adroitly pointed out the knack of physicians to depend on some sort of test especially when making a simple diagnosis.
The context is the always fascinating ‘Puzzler’ cases that are submitted by the readers. The case appeared in the September issue of the journal. The letter points out that the case is a “blatant example of what is happening to medical education”. The basic elements of our encounters with patients are the history of the illness and the physical examination. Dr. Dave points out that these skills are disappearing and are replaced by tests, radiographic studies, and more tests. Sometimes the tests are performed prior to taking a history and doing an examination. In this case, a thorough history and physical examination may have revealed the diagnosis. Tests sometimes beget more tests and this may not always be necessary and may be costly.
I see this way too often in the practice of allergy. Allergy tests are done prior to visiting with the physician, they are done as panels, and they are sometime performed in the operating room. Sometimes no relevant history is taken and the tests are used to make the diagnosis and treatment plan. In some situations this may work, however I have seen children who were denied foods that they enjoyed (and needed), families who were told to make drastic changes in their lives, animals that were sent elsewhere, and a significant amount of money spent not only for the test but also for special diets and gizmos to alter the environment. This is not fair nor is it the proper way to do an allergy evaluation!
An allergist/clinical immunologist spends a significant amount of time deciding if the complaints fit a template or pattern of allergic disorders by taking that detailed history and doing an appropriate physical examination. The relevant allergens are then selected for testing. What is ‘relevant’? What I mean by relevant is that they are items that the child is exposed to and with that exposure there will be a reliable set of symptoms. Cause and effect relationships need to be established. For example, if milk is taken everyday and with the drinking of milk there are no symptoms of allergy, then the test should not have been done (given this history) and if the results were positive, then they are irrelevant. The value of the test results is only as good as the story or history that supports it.
Remember, the tests make no child allergic. The test only means that antibody is made or has been made. The allergic child has a set of symptoms consistent with allergy with positive tests to relevant allergens. I go more into this topic in the What is Allergy and Testing pages on this site.
Thank you Dr. Dave for lamenting the possibility of lose of an important part of medical training.
Every now and then I will bring in what I call ‘pet peeves’. These are for me everyday experiences that I have developed a humble opinion about and when the mood strikes I will elaborate on my perspective (properly plugged as pet peeve perspectives, perhaps?). So here goes – Pet Peeve Number 1- where to go for allergy care?
There are a number of health care specialists who offer allergy evaluations and allergy directed care. I have seen over the past week three new children who have had evaluations for allergy by someone who offers ‘allergy’ care and they were not allergists. In one instance a type of allergy test was done in the operating room. In one child, intradermal tests for foods were done ( a technique that is replete with false positive results) and most concerning was one child who was tested for foods, found to have a few positive responses, and was given a set of instructions that may have caused a problem. As I reviewed the previous allergy test records with the family I noted that the instructions were “3 days of total avoidance followed by 1 day of exposure to as much as could be eaten of the positive food”.
In the world of IgE-mediated, type-one hypersensitivity food ‘allergy’ reactions (see pages on What is an Allergy and Allergy Tests) the current recommendation is full and strict avoidance of the offending food. There is an evolving science that is helping with prevention and with treatment of some food allergies, but we are not there just yet. I have never come across a program that involves days of avoidance followed by overindulgence, nor could I find anything in the literature regarding this. This could be a very dangerous recommendation especially for a child who may have a systemic response such as hives or allergic shock.
The presenting problem was recurrent ear infections. Now here is where philosophies come into play. The track record even in the best designed study is that at a maximum 1/3 of children with recurrent ear infections may have allergy as a contributor. Between the lines, the allergens were inhalants and the 1/3 of children affected was the one study with the highest fraction. Many of the studies on this connection had fewer children triggered by allergy. In regards to foods, the reports from double-blinded placebo-controlled food challenges (this being the best way to prove a reaction) have shown that foods are a rare cause of isolated respiratory tract symptoms. What was also observed was the fact that if a food was involved, the families suspected it before the evaluation. Again the answer was in the medical history.
Who offers allergy care- well anyone can offer and perform some type of test for allergy. Therein lies the problem. Be ware of what and who is out there. Get the best for your investment of time, money, and safety. The American Academy of Allergy, Asthma, and Immunology (AAAAI) has a issued a position statement about questionable tests and testing procedures for allergy. The bottom line on these evaluations is that it is not money well spent!
We have primary caretakers, allergists, and otolaryngologists (ENT) tauting expertise in allergy.
Let me describe an allergist- This is an individual who has primary training in either pediatrics or internal medicine. The individual then has done a 2-3 year training program in allergy/immunology and is then eligible to sit for their specialty boards. Allergy/Clinical Immunology is a conjoint board, one of the few that credentials trained individuals to see both children and adults within the context of their specialty. The graduate of the fellowship training program has the opportunity to sit for their specialty boards and they become a board certified allergist-clinical immunologist. They could then join one of two national groups that help set the standards of allergy care, the American College of Allergy, Asthma, and Immunology (ACAAI) and the American Academy of Allergy, Asthma, and Immunology (AAAAI). Through a tenure of membership in these organizations and in their primary specialty, the allergist may become for example a fellow of the American Academy of Pediatrics (AAP) and a fellow of the AAAAI.
Resolves for my pet peeve number 1.
1. Ask about credentials- What is the primary specialty- pediatrics, internal medicine, family practice, or ent surgery?
2. Where was the allergy training – a fellowship, part of surgical training, a course?
3. Is the practitioner boarded in the specialty of allergy? Are they board eligible in the specialty of allergy?
4. Are they a member of a peer group- ACAAI or AAAAI?
5. This one is very biased- although the allergist/immunologist has training in each world I would suggest the pediatric-trained allergist for the children. From my experience at a wonderful children’s hospital- you just have to know about kids and be kid-oriented to be more effective in what we do.
FEL
How about this as pet peeve #2 in my allergy practice? I will share my thoughts and practice guidelines regarding the old adage is “the child too young to test for allergy”. I have heard this countless times from concerned parents. There may be some truth to this, but it depends on the situation. Oh, by the way this pertains to any type of allergy test. Let me elaborate.
First off, allergy takes time to develop. There has to be exposure to cause sensitization. Sensitization involves stimulating the immune system to make that allergy antibody called IgE. That antibody then circulates through the body and binds to cells in the gut, skin, respiratory tract, and cardiovascular system. So we need time, a genetically prone child (thank you mom and dad only please), and exposure.
Secondly the nature of the allergen is important to consider. We get a daily dose of food so food allergy has a chance of developing early in life. Inhalants such as animal dander, insect parts, mold spores, and pollen take longer. We then also need to consider the allergen of concern.
We can see food reactions beginning about 2-3 months of age and usually presenting as a form of eczema (dry, itchy, scaly skin) called ‘atopic dermatitis’. In our pediatric allergy clinic at Riley we can and do test infants with eczema looking to see if a food is a possible stimulant for the condition. We skin prick test for egg white, milk, wheat, soy, peanut, and fish (these foods account for more than 90% of food allergy in children) and provide the family with the results of the skin tests (they take only 15 minutes) and a game plan prior to leaving the office. Here the point is that food allergy can be seen in the very young and we can effectively test. So with the proper condition, that being a skin problem, allergy testing can be done and can be very helpful in the very young. Respiratory tract allergy however is a different story.
Respiratory tract illnesses- asthma, rhinitis, otitis media, and recurrent sinusitis can be due to inhalant allergy. Keep in mind that there are other things to also consider such as day care exposure, irritant responses, and possible structural problems. Inhalants act differently. The first point to be made is that the child has to be God’s earth for at least one year before inhalant allergy can appear. Furthermore, it may take two but for the most part three outdoor seasons for the child to become sensitive to the pollens of trees, grasses, and weeds. This is obviously dependent upon where you live. In Florida, California, and Hawaii for example, the pollen season tends to be all year round. But here in Indiana the pollen seasons are limited to shorter durations. For indoor allergens such as insect parts, danders of dogs and cats. and mold, it takes at least a year for the exposure, sensitization, and symptom sequence to start. Testing an infant to inhalants/pollens would not reveal clinically relevant sensitivities.
So is the child too young to allergy test? I use these general guidelines-
FEL
I have never written a letter to the editor that I have actually sent. Most of them wind up in the circular file (aka file 13, trash etc). I usually feel better having written them, but I do not have a track record in this regard. Perhaps doing this blog has emboldened me. After all it is an opinion, but sometimes we see things that we truly feel are wrong and we need to warn others about these wrongs.
The story goes as follows. I have subscribed to a newsletter called ‘Bottom Line Personal’. This publication has short articles on a variety of topics. For example, the last issue has quips on investing, real estate, psychotherapy, painkillers, career starting, bed sharing, and dangers in your garage (as I listed these it made me wonder why I subscribe). There is a page that talks about the purpose of the publication which is to bring to the reader the best information from the most knowledgeable sources in the world in helping the reader gain “greater wealth, better health, more wisdom, extra time and increased happiness” (this is a direct quote). Way at the bottom of the disclosure panel is the statement that they publish the opinions of expert authorities in the fields. I came across an article in the news column that started “If you think you are allergic to a certain food…..” That certainly caught my eye. As I read on my interest turned to rage (not really rage but my feathers were rattled). The first line continued “….. but you aren’t sure which food-consider having a blood test for the immunoglobulin IgG, says the author of a book called ‘The Source: Unleash Your Natural Energy, Power Up Your Health and Feel Ten Years Younger'”.
So I am concerned that my newsletter (one I subscribe to) which focuses on saving money and promoting health would promote this book specifically this concept of IgG to food as being something of value and something well established in health care. So I carefully composed a letter citing references from the Food Allergy and Anaphylaxis Network (FAAN) and from the American Academy of Allergy, Asthma, and Clinical Immunology. I also did a literature search on the author of the book using PubMed and OVID. My letter explained that the measurement of IgG to food is unproven as a diagnostic test and should be considered experimental. It is known that IgG to foods does not sort out a healthy from a sick population. The thought is that we see IgG to food in healthy people. To date, this is a test looking for a disease.
Thinking that I may have missed something, my search for published articles by the author on this topic in peer-reviewed journals came up with nothing.
I went on to point out that IgG to food is on a rather long list of unproven diagnostic tests for allergy. I pointed out that prior to publishing their review on the topic that they should have done more research on the topic, utilizing position statements from the major organization involved with allergy and perhaps used a literature review of evidence-based medicine to see the value of a test for IgG directed to foods. My bottom line was that this was not money well spent and could possibly lead to more harm for someone. I even went so far as to make some analogy to the use and sale of snake oil.
I carefully looked over my 750 word editorial, criticized the editors for violating their own standards and sent it off. Needless to say, I thought I was doing a service in pointing out my concerns.
Respectfully submitted,
Fred Leickly
Story continued- I got a response from ‘Bottom Line’- “Thank you for your email. We welcome your feedback. We find that on occasion even well-respected experts disagree and this appears to be one of those times. Again, I thank you for taking to the time to explore this topic with us.”
Ugh! I still feel better for the effort!
I have many patients and families who have significant concerns about peanut allergy. I have been at Riley for 15 years, and during that time I have seen a significant rise in peanut allergy. Once upon a time I would see a new peanut patient about once a week. Now it is closer to a daily occurrence. I have had a couple of my kids (patients) featured in the newspapers regarding peanut allergy and one of them was the Riley (State of Indiana) representative for the Child’s Miracle Network for peanut anaphylaxis. I am always looking for more on peanut allergy and am eager for a way to take the fear out of this situation.
There has been a considerable amount of research going on with peanut allergy. Most recently, in the February 2009 edition of one of the premier journals of allergy, the Journal of Allergy and Clinical Immunology, there was an article from the United Kingdom that looked at peanut consumption in a household as a risk factor for the development of peanut allergy. The article was accompanied by an editorial from a dear friend of mine who is one of the lead figures in this quest for answers about peanut allergy, Dr. Wes Burks- chief of allergy at Duke University (actually, Dr. Burks and I trained together at Duke back in the day).
The article concludes that high levels of exposure to peanut in infancy promote sensitization. Low levels of exposure in the environment may be protective. There was no effect of mother’s consumption of peanuts during pregnancy or lactation. The findings supported the idea that sensitization (making an IgE antibody) to peanut occurs through the child’s environment.
Dr. Burks’ editorial urges caution regarding some of the recommendations and conclusions. The editorial also talks about an article yet to be published, including some real world differences in the peanut cultures of the populations in the study. In the current study, a questionnaire was used to address maternal exposures/consumption of peanut. Dr. Burks points out that there can be problems with recall information used for a questionnaire. The article suggested that avoiding peanuts lessens tolerance and increases the risk of allergy through possible skin exposure to peanut. Dr. Burks issues caution regarding advice about early feeding to prevent food allergy. The theory has not had enough support to make this part of our clinical practice.
The ideas in the article are interesting, exciting, and provocative.
I also had a few ideas on the article. In my professional career I have had great mentors, and one in particular: Dr. Charles Hoppel. I met Dr. Hoppel as a graduate student in pharmacology at Case Western Reserve University. From him I learned how to look at an article with a very critical eye. Here goes my perspective on the article ‘Household peanut consumption as a risk factor for the development of peanut allergy‘.
First, the journal is what we call top tier, highly peer-reviewed. Second, the group has a track record in the area of interest. Third, the work was supported by a government grant. These are all good things.
The purpose of the article was to ‘investigate the relevant routes of exposure to peanut that lead to peanut allergy’.
Now how did they do this or what were their methods? The study was a questionnaire-based case-controlled study of children less than four years of age. There were three groups; children with peanut allergy, children at high risk to develop peanut allergy, and a low-risk control group. The questionnaire was completed by parents before they knew that the child had peanut allergy. There were 133 with peanut allergy, 160 high-risk controls, and 150 low risk controls. If peanut allergy was suspected, the child was excluded from the study. Most of the peanut allergic children had eczema. A case (peanut allergic child) had a positive skin test, a positive blood test, or a positive food challenge. The high-risk to develop peanut allergy were children with egg allergy (about 20-30% may go on to develop peanut allergy).
Detailed questions were asked about peanut consumption by all household members during the child’s first year of life and mother’s peanut habits during pregnancy and during breast feeding. The questions asked about peanut containing foods, frequency of ingestion, and how much was eaten. Household peanut consumption was then calculated.
Eczema was present in 92% of the peanut allergic group and 88% of the high-risk to develop peanut allergy group. Concerning peanut consumption during pregnancy and breastfeeding:
Household peanut consumption:
Next the importance of the route of exposure to peanut was evaluated with Odds Ratios and logistic regression. The authors looked at the numbers in the groups who had one of three exposures (environmental, pregnancy, or breastfeeding) in one of three groups (peanut allergy, high-risk to develop peanut allergy, and the normal controls). When the peanut allergy group was compared to the low risk controls, only household peanut exposure was associated with peanut allergy and not consumption of peanuts by the mother during pregnancy/breastfeeding. There were 134 children in which there was no maternal peanut consumption during pregnancy. In this group peanut allergy was more common with increasing household peanut exposure.
The study also looked at the source of the peanut exposure. Most of the household exposure was peanut butter followed by whole peanuts.
The last analysis dealt with that high-risk group who had known egg allergy. This group had low household peanut exposure and tended to not develop peanut allergy. The question was asked as to why those in this group with rather high household peanut exposure did not develop peanut allergy? The suggestion was made that it was due to well-controlled eczema (skin barrier not broken allowing environmental access) or they were tolerant due to ingestion of peanuts prior to age 12 months.
The authors concluded that high environmental levels of peanut during infancy lead to sensitization with low levels offering protection. There was no effect from maternal consumption during pregnancy/breastfeeding. Sensitization occurs through environmental exposures. Early dietary introduction may be the way to develop peanut tolerance.
Why do I suggest that the title be changed? Allergy means a reaction; therefore, peanut allergy would be a reaction to peanut (according to the definition by the World Allergy Organization). I expected, based on the title, that this would involve children with reactions to peanut. The study actually excluded anyone who had a suspected peanut allergy. The population was predominantly children with eczema, a condition in which positive tests to peanut are found with great frequency without symptoms and without exposure. Eczema (atopic dermatitis) is notorious for false positive tests to foods. The definition of a case was a positive skin test, a blood test over a critical level, or a positive food challenge. I think the proper case definition would include: a positive test for specific IgE (skin or blood) and a positive food challenge. We do not know how many children fulfilled the criteria of test and symptoms with exposure.
The authors did point out that the case criteria was validated in study published in the JACI in 2005. In the 2005 study, patients with a suspected history of peanut reactions were used. This type of patient was excluded from the current study. In the 2005 study, 40 children from a generalized health survey were used, but we are never told how many of that group were without a history of a reaction to peanut. I am not convinced that the extension of case definitions from a symptomatic peanut group are applicable to a group in which a history of peanut reactivity was an exclusion criteria. This should be household peanut exposure and sensitization since we do not know who if any in the group will actually react or did react in the food challenge. Perhaps just looking at that group would be of value.
This is very interesting work and very provocative. Should peanut sensitization become a public health issue? Can we validate these finding in our population?
Respectfully submitted,
Fred Leickly
I recently attended the 2009 annual meeting of the American Academy of Allergy, Asthma, and Immunology(AAAAI) in Washington, DC. There were five days of extraordinary educational activities (March 13-17, 2009). I thought that while I could still read my notes I would share with you a few things I observed, heard, and learned in the ever evolving world of allergy. I plan to adopt many of these changes in my practice.
The meeting’s agenda covered a wide variety of clinical conditions. It would have been impossible to attend every session. I chose sessions on the allergic environment, eczema, immunotherapy, food allergy, re-certification, headaches, and asthma. There are a number of ideas that are evolving and a number of things currently done in allergy/asthma care that need to change. Each and every one of these topics is truly worthy of more extensive review. I would be happy to use this blog to delve into topics in more detail (per request).
Atopic Dermatitis (aka Eczema)
I still need to be convinced regarding what to call this condition. Dr. Jeff Travers (chief of Dermatology at the IU School of Medicine) and I go back and forth on this topic. During the meeting I heard the concept of extrinsic and intrinsic atopic dermatitis. Extrinsic means from the outside and intrinsic from the inside. These terms have also been used for years to describe two presentations of asthma: extrinsic asthma due to allergy, and intrinsic asthma when no allergy is found. The word atopic means 1) the tendency to come from families with allergy, 2) to make the antibody seen with allergy (IgE, which would be elevated) and 3) to have positive allergy tests. Thus, Intrinsic AtopicDermatitis means no allergy demonstrated (intrinsic) in a condition associated with allergic sensitization (atopic). This blending of terms leads to confusion–why not stick with the simpler term of eczema?
I learned about the use of silver impregnated clothing to decrease the amount of bacteria on the skin. Skin bacteria can cause flaring of atopic dermatitis.
A number of genes associated with atopic dermatitis have been discovered. These discoveries should increase our understanding on how this condition starts and hopefully how we can manage it better.
There was information on allergens that contain enzymes called proteases and how these protease containing allergens aggravate the skin.
Probiotics have been used to treat allergic conditions especially conditions related to food allergy. A review of studies on probiotics have not shown them to be effective in preventing or treating atopic dermatitis.
I listened to debates about being proactive in skin care therapy vs. being reactive. Proactive would be trying to prevent and reactive being treating only when there is a problem. This idea was particularly interesting. Atopic Dermatitis Guidelines and package inserts for a variety of medications used for atopic dermatitis treatment stress short courses of use, the reactive approach. The proactive debater posed the problem of a chronic disease that will have episodic flaring. The abnormality of the skin is there all the time requiring the need for medication to be used perhaps twice a week to avoid flares (those times when the skin is more itchy, more inflamed, and more broken down). Pediatrics deals extensively with disease prevention. My pediatric perspectives are preventative- proactive. All too often we (as patients) tend to be crisis-oriented or reactive to chronic conditions. I am obviously on the proactive side of this argument.
Therapies emphasized moisture and more moisture. Keep these kids wet! This is clearly a major step that is contrary to previous approaches that recommended the avoidance of frequent soaking/bathing. The avoidance of baths is clearly one of those long established principles of atopic skin care that has fallen by the wayside in contemporary skin care.
Foods are an issue in atopic dermatitis. The protease containing allergens such as molds, pets, and mites may have a role in triggering flares.
In Boston a program that has had success includes insuring compliance with the medications (taking them as prescribed), addressing the parents concerns about medication side-effects (helps with compliance), decreasing the itch, and increasing sleep. These are all essential elements to help with control of the condition.
Of note, we need to re-think the role of a specific therapy and make adjustments. Antihistamines are frequently used in atopic dermatitis. In allergic rhinitis and in hives, these products help control itch. However, in atopic dermatitis, the antihistamines have little effect on itch. The role of the anti-histamine is to sedate. Most of the scratching happens at night. A sedating antihistamine used at night works best.
Asthma
There were a number of new ideas regarding asthma. Look for vitamin D to have a possible role in treatment.
Current recommendations from evidenced-based asthma guidelines point out a difference between adults and children and the use of the long-acting bronchodilators in the two populations. These agents are called long-acting broncho-dilators (LABAs). In children, we should increase the dose of the inhaled corticosteroid before adding a LABA. This recommendation appears in two major asthma guidelines with type A evidence used to support the recommendation. This type of evidence (A) means that there are a substantial number of studies that support this statement.
Asthma may be related to bacterial colonization at birth and to the occurrence of the common cold virus later in life. Evidence was also presented regarding the observation from large population studies that the process of airway inflammation starts well before actual symptoms. We heard about diet, viruses, stress, ozone, and endotoxin having a role in the development of asthma. The gene or genes for asthma need to be present. These genes then need to be activated or expressed for the child to show the signs and symptoms of disease. Bacterial colonization and a variety viruses may have a role in activating the genes.
Headaches
This was a great session. The audience heard from an ENT surgeon, an allergist, and a neurologist regarding their approach to headaches. The consensus was that migraine is the biggest player in these situations. The connection of allergy to headache has always been a concern. However, headache is not a manifestation of allergy. There are many studies that have looked at this. People with headaches can have positive allergy tests but does that make the allergen the cause of the headache? Think about other conditions or associations. Could there be an allergic cause for an appendicitis?
I heard of the concept of ‘allergic appendicitis’ during this presentation. It was very odd to hear about this in a headache session, but a valid point was made. This concept of the allergic appendix was compared to allergic headaches. Follow along; data from a national health survey from 1994 indicated that 50% of the population reported that they had allergy. So if someone who had problems with the appendix was allergy tested, the chances are very high that allergy would be found. This however does not make the inflammation of the appendix due to allergy. You can find a significant number of positive allergy tests, be sure of why the tests are being ordered. Think migraine more often as a reason for headache. Allergy is not a major reason for headaches.
Food Allergy
The biggest news from the meeting was the work done by Wes Burks at Duke on peanut allergy. This is exciting and long awaited for those who have peanut allergy and for the families who have someone with peanut allergy. Immunotherapy for peanut trials have allowed the equivalent of about 12 peanuts to be eaten without any problems/reactions. This would certainly take the fear from accidental exposure to peanut especially from tabletops at school cafeterias. I have to check my note again, but I had written down the treatment would be a suppository(?).
There was a very popular abstract (a quick presentation of work in progress prior to it being published in a journal) on food allergy and the over- use of panels for food allergy (pet peeve). A New York Times article a few months ago reported that food allergies were being over diagnosed. Dr. Sears at National Jewish Hospital in Denver, Colorado reported on over one hundred children seen at their center who had food allergy as determined by blood test panels. The average number of food allergies reported were six. After undergoing food challenges the number decreased to only 2 foods. 88% of the foods this group of children were told to avoid based on RA ST panels were added back into the diet. Using a food challenge, no one with meat ‘allergy’ had a positive food challenge (where meat caused a problem), 88% of the grain ‘allergic’ children were negative on challenge, and 83% of the fruit and vegetable group were also negative after a food challenge. Bottom line- the use of these panels is giving falsely positive information and leading to a misdiagnosis of food allergy.
Allergy Testing
I learned that I should no longer use the word RAST. The term is outdated and refers to a technology not used. The blood tests for allergens should no longer have a 0-6 grading scale and should only be reported in what is actually measured kU/l of serum. The test measures a concentration of a specific antibody in the blood. The relationship of that concentration to clinical activity needs to be determined by the clinician. I predict that the interpretation of the blood test results may be a huge issue.
A new in vitro or blood test for specific IgE in the blood is called an ISAC chip. This technology will help with cross-reacting proteins. We see the problem of cross-reactivity with multiple positive allergy tests to legumes (peanut, soy, beans, and peas). I think this will be a very worthwhile test in allergy.
There are three blood tests out there for detecting specific IgE. These are the Immunolite, ImmunoCap, and Hytec. Each of these measure something different. They measure a different population of IgE antibodies and may not be comparable. Caution was advised regarding the blood tests for specific IgE. The physician should know the method used, the validity of the assay, the performance of the laboratory in doing the assay, and realize that no test for allergy is infallible.
Conclusions
Each and every one of these topics could stand alone for more detail and interpretation and I would be most happy to elaborate in more detail. Let me know if you would like more information by adding a comment. If there continues to be an increase in the use of specific IgE panels (as advocated by those who market these tests) we will be doing significantly more food challenges in our office. Usually we are doing food challenges for those who may have outgrown a food allergy. We certainly can offer a food challenge for a child who has been told that food allergy exists based on blood test results. One of my tasks upon my return to the office is to look at our track record of doing food challenges. I hope to report on our successes and failures for our food challenge experience with milk, egg, soy,wheat, and of course peanut.
Respectfully submitted,
Fred Leickly
I had the chance to moderate a course given by the American Academy of Pediatrics (AAP) last weekend. For many years I had the role as a speaker for these programs. These are great opportunities for primary caretakers, pediatricians and nurse practitioners to hear some very practical approaches to common problems in pediatrics.
Providence, Rhode Island was the host city for this Practical Pediatrics offering. In early April Providence does not have a lot going on. The weather was wet and cold. This kept us indoors. The seafood and Italian food were great! I also recommend the IMAX 3-D movie Aliens vs. Monsters. Despite the inclement weather, I did learn a few new things and learned to appreciate many other aspect of care for our children.
Dr. Martin T. Stein, Professor of Pediatrics at the University of California, San Diego shared a few thoughts on pediatrics in general. He presented things that made me stop and wonder about the incredible job that is done by healthcare providers that look after our children. Did you know that for well child care the recommendation is for 31 visits? Back in the day (okay, 1974) only 14 well child care visits were the standard. I am sure this increase is due to the need for guidance, safety, development, and prevention. It makes our pediatricians busier. I also learned that our children benefit from a level of primary care above what is offered in other countries. The United States is the only country where board certified pediatricians provide that essential well child care. I have always held our pediatricians in high esteem. I learned a few things that have increased my respect for them and for what they do.
I learned a few more things about allergy and had a few of my standard issues emphasized by Dr. William T. Boleman, who is the Chief of Allergy at the Keesler Medical Center (USAF) in Biloxi, Mississippi. I learned that controversies in allergy are not at all unique to Indiana. Mississippi seems to be affected by theories, practices, and therapies done under the name of allergy, but clearly without a shred of evidence that allergy accounts for the problem. Dr. Boleman talked about sugar, wheat, yeast, chemical, electromagnetic radiation, hormones, and voodoo allergy testing including IgG antibodies to foods. One of his messages was to be sure that the story matches a condition in which allergy may be a cause. History taking remains an essential part of any allergy evaluation.
I have always enjoyed listening to the dermatologists. Their lectures are replete with pictures and practical information on a wide variety of things that can affect our skin. Dr. Miriam Weinstein from Toronto Sick Children’s hospital shared her opinion on a condition that is often seen by both the allergist and the dermatologist. That condition is atopic dermatitis, a form of eczema that has associations with allergy. I was surprised and concerned after the talk on evidence-based therapy of atopic dermatitis. She had pulled references from the dermatology literature. The evidence-based review is a critical summary of good and bad studies. One of my courses in the public health program actually taught us how to critique one of these reviews. It is quite an art to go over a vast literature looking for answers to specific questions and making sure that the methods used to get that answer were without any flaws.
The things that I learned and what I thought would be very helpful for the children I see with atopic dermatitis in my allergy practice include the emphasis that it is not just one thing such as a food that will trigger a flare of itchy, dry, flaky skin. There are many different reasons for the condition to flare and sometimes it just happens. When we discover something like a food that could trigger that is great because there is one less thing to worry about.
We also need to keep the skin as moist as possible. Moisturizing the skin can be considered front or first line therapy. These children need to be so slicked-up that they just slide through your fingers.
Using the topical steroid ointments once a day may be just as effective as using them twice a day and using them a few times during the week even when the skin is clear may help keep the skin from flaring.
I now emphasize that the use of the anti-histamines is not so much for the itch component of the skin, but for sedation. A significant amount of scratching of the skin occurs during the night. Helping with sleep by taking advantage of the sedative aspects of antihistamines makes a difference. Choices here would be agents like Benadryl or preferably Atarax (Hydroxyzine).
Skin infection needs to be controlled. The scratching and breakdown of the skin leads to infection. The infected skin then causes further scratching and misery.
Also, contrary to what an allergist would like to believe, being allergic to house dust mites and consequent house dust avoidance techniques may not make any difference in controlling flares.
Food allergy may not be the cause of many of the flares. Unfortunately these children have many positive skin tests and the track record is that the positive predictive value of the food test is about 50%. So when the allergy test for food is positive, there is a 50/50 chance that it is relevant and that exposure to that food causes a flare of the skin. Of all the foods that have been associated with flaring, egg is the most common.
It is important to keep learning new things, new perspectives, and be open to changes that may be of benefit to our patients. Hopefully a few of these tidbits may help.
Fred Leickly
Leickly Stories 