This summary was compiled from the tweets posted by the following allergists/immunologists who attended the 2012 annual meeting of the American Academy of Allergy Asthma and Immunology (AAAAI): Dr. Melinda Rathkopf @mrathkopf, Nathaniel Hare M.D. @AllergyTalk, Robert Silge, MD @DrSilge, and Sakina Bajowala, M.D @allergistmommy. The tweets were labeled #AAAAI. The text was edited and modified by me.Eosinophilic Esophagitis (EoE)
Esophageal T cells are activated in Eosinophilic Esophagitis (EoE). CD69 is used as a marker of activation,
Eosinophilic esophagitis often presents with dysphasia and food impactions. There is no pathognomonic endoscopic finding for EoE. It can take 4-5 simultaneous pan-esophageal biopsies to confirm the diagnosis of EoE (>15 eos/hpf). Patients with eosinophilia in the esophagus may respond to proton pump inhibitor monotherapy. This is a separate condition from EoE.
The most commonly reported EoE complication in adults is esophageal food impaction, followed by esophageal stricture.
Both aeroallergen and food hypersensitivity may exacerbate the symptoms of EoE.
Abnormal, subepithelial collagen deposition is a known complication in EoE in pediatric and adult populations. Topical corticosteroids, namely bidesonside, can resolve fibrosis in EoE. Can dietary therapy resolve fibrosis? Yes, but to a lesser degree.
Eosinophilic Esophagitis (click here to enlarge the image).
There are 3 different approaches for dietary therapy in EoE:
- Elemental diet
- Test-directed elimination diet
- Empiric elimination diet
Elemental diet for EoE treatment
There is 96% symptom resolution on amino acid formula plus apple or grape juice (Am J Gastroenterol 2003).
Pros: Elemental diet is highly effective and no testing needed. Cons: palatability of elemental diet is poor, there may be need for tube feeds, cost is high, social isolation may become a problem, etc.
Test-directed elimination diet for EoE treatment
Test directed diet was evaluated in a JACI 2002 article by Spergel et al., using a combination of prick and patch test. It led to 69% symptom resolution, and 23% partial improvement.
Test-directed diet pros: reasonably effective in children, more socially acceptable. Cons: extensive testing is required, some test not validated, for example, patch testing with foods.
Skin testing in EoE
Dr. Allen advocates skin testing in EoE even with 6 food elimination diet - if nothing else it may guide which food to reintroduce last. Dr. Chehade argues that NPV of skin testing in EoE is too low to be useful, a study guiding reintroduction showed that SPT was useful only 22% of the time. She does argue that SPT is worth doing prior to reintroduction to rule out de novo food allergy while food was being avoided.
PPVs in skin testing for common foods in EoE are highly variable. Skin testing with fresh foods may be more reliable for EoE guidance.
Patients with EoE are often poly-sensitized to foods. Grains, milk, egg, soy, meats and white potato are common triggers. Interpretation of patch testing for foods in EoE may be helpful, but requires validation, and further studies.
Although not a purely IgE mediated disease, patients with EoE commonly experience food-related anaphylaxis.
Empiric diet for EoE treatment
Empiric diet consists of removal of the most common food triggers without testing. Removal of milk, wheat, egg, soy, nuts and seafood associated with 74% improvement.
74% of children improved on 6 food elimination diet. Milk is by far the most common food. Similar study in adults showed 50% improvement.
Empiric elimination pros: it is reasonably effective, no testing is needed, socially acceptable. Cons: multiple foods are eliminated, and may cause nutritional deficiency.
Wheat, rye, barley removal in adult EoE had little effect - only 17% improved (Simon et al, Allergy 2006).
Katrina Allen, MD, PhD discussed Reintroduction of Foods after dietary elimination for treatment of EoE:
Think of EoE as "eczema of the esophagus" (EoE used to be called “asthma of the esophagus”).
Optimal end points of EoE therapy is not known, e.g, using clinical symptoms vs. the need to repeat biopsy.
Dr. Allen said that when it comes to reintroducing foods after remission of EoE "we all fall apart". There is no consensus on how to monitor.
We need SPT in EoE for managing co-existing food allergy (FA), management of EoE diet to extend empiric diet, or guide reintroduction of foods.
Dr. Allen is using 4 food elimination diet: milk, egg, soy, wheat. Studies are ongoing on its effectiveness.
Confounding factors in EoE
Consider other causes on esophageal eosinophilia: GERD, Celiac disease, IBD, fungal infections, allergic rhinitis, drug allergies. Dr. Spergel reports that for diagnosis of EoE, he puts all patients on a PPI AND a nasal steroid before biopsy. Both allergic rhinitis and GERD can cause increase in eosinophils in the esophagus.
Eosinophilic gastroenteritis (EGE)
Eosinophilic gastroenteritis (EGE) is best diagnosed by suggestive endoscopic endoscopic and pathological findings. No established eosinophil count for diagnosis of eosinophilic gastroenteritis. First line acute treatment in eosinophilic gastroenteritis is prednisone 20-40 mg daily. Food triggers are rarely found in EGE. This is in contrast to EoE.
Hypereosinophilic syndrome is diagnosed by peripheral absolute eosinophil count of >1500 on 2 separate occasions. Overlap is often seen with EGID.
Most effective maintenance treatment in EGID is non-enteric coated budesonide.
Dr. Spergel reports his standard of care for EoE is to remove foods identified by skin testing plus milk.
Swallowed steroids
According to some experts, first line treatment in EoE is swallowed fluticasone, 440-880 mcg twice daily. Second line treatment is oral viscous budesonide (OVB).
Patients develop Candida esophagitis about 15% of the time with swallowed steroids for EoE.
Dr. Spergel has switched from swallowed fluticasone to budesonide, as he found it difficult to teach patients how to swallow the fluticasone. In contrast, Dr. Chehade states she has better luck with fluticasone. Just make sure people fast for 60 min after puffing in it in their mouths.
There are no data on IT helping EoE. Some anecdotal reports that it does. Seasonal EoE is reported, but it is VERY rare.
Monitoring of EoE
Symptoms in EoE are not a reliable marker for disease activity.
There are no objective measures to follow the disease course in EoE, aside from endoscopy AND biopsy. Non-invasive measures are needed, but they are not available at this time.
References:
EoE: Updated Consensus Recommendations. JACI 2011;28:3-20.
Allergists achieved highest use of social media by any specialty
During the 2012 AAAAI meeting, the allergists achieved the highest use of social media by any specialty. There are more than 100 allergists on Twitter and 30 of them posted simultaneously from the annual meeting, broadcasting thousands of tweets tagged with #AAAAI. The annual AAAAI meeting was attended by approximately 5,000 people. In comparison, the 30 allergists on Twitter reached 250,000 people (measured by TweetReach.com on 03/04/2012).
This summary was compiled from some of the tweets posted by Dr. Melinda Rathkopf @mrathkopf, Nathaniel Hare M.D. @AllergyTalk, Robert Silge, MD @DrSilge, and Sakina Bajowala, M.D @allergistmommy. I would strongly encourage you to post updates on Twitter from the CME conferences that you are planning to attend in the future. Here is how to do it: Twitter for Physicians: How to use Twitter to keep track of the latest news and scientific meetings, and share information with colleagues and patients.
Disclaimer: The text was edited, modified, and added to by me. This is one of a series of posts that will be published during the next few weeks.