Correspondence

Sublingual Immunotherapy

N Engl J Med 2008; 359:869-870August 21, 2008

Article

To the Editor:

In his discussion of allergic rhinitis and the clinical use of sublingual immunotherapy, Frew (May 22 issue)1 reports that the adverse effects of such therapy have been limited mainly to the oral cavity, with only a few cases of anaphylaxis reported. To our knowledge, the studies whose results have been published so far did not look into the incidence of eosinophilic esophagitis with sublingual immunotherapy. Eosinophilic esophagitis is an emerging worldwide disease of unknown cause that mimics gastroesophageal reflux disease and can lead to esophageal narrowing and stricture.2 The majority of patients with the condition have evidence of food and aeroallergen hypersensitivity. However, only a minority of patients have a history of anaphylaxis, suggesting a distinct mechanism of IgE-mediated activation of mast cells and basophils.3 A temporal association between eosinophilic esophagitis and pollen exposure has been described.4 It is plausible that the repeated delivery of specific allergens through sublingual immunotherapy could lead to delayed cell-mediated responses within the esophagus. We wonder whether an evaluation of the long-term incidence or aggravation of eosinophilic esophagitis with such therapy is warranted.

Arturo J. Bonnin, M.D.
Dawn M. Zacharias, M.D.
Wright State University Boonshoft School of Medicine, Dayton, OH 45458

4 References

1. 1

   Frew AJ. Sublingual immunotherapy. N Engl J Med 2008;358:2259-2264
   Full Text | Web of Science | Medline

2. 2

   Furuta GT, Liacouras CA, Collins MH, et al. Eosinophilic esophagitis in children and adults: a systematic review and consensus recommendations for diagnosis and treatment. Gastroenterology 2007;133:1342-1363
   CrossRef | Web of Science | Medline

3. 3

   Blanchard C, Wang N, Rothenberg ME. Eosinophilic esophagitis: pathogenesis, genetics, and therapy. J Allergy Clin Immunol 2006;118:1054-1059
   CrossRef | Web of Science | Medline

4. 4

   Fogg MI, Ruchelli E, Spergel JM. Pollen and eosinophilic esophagitis. J Allergy Clin Immunol 2003;112:796-797
   CrossRef | Web of Science | Medline

Author/Editor Response

Bonnin and Zacharias raise an interesting question. Eosinophilic esophagitis is a relatively rare condition and one that would be extremely unusual in the type of patient who is being considered for sublingual immunotherapy. A patient who had eosinophilic esophagitis as the primary problem would not be offered sublingual immunotherapy, so the exacerbation of the condition by such therapy is not a very likely scenario. Could sublingual immunotherapy disclose eosinophilic esophagitis in someone who had the condition at a subclinical level? I accept this as a theoretical possibility, but to the best of my knowledge, such an occurrence has not yet been reported, even at the anecdotal level, among the many thousands of patients who have received sublingual immunotherapy for rhinitis in Europe.

Anthony Frew, M.D.
Brighton General Hospital, Brighton BN2 3EW, United Kingdom
anthony.frew@bsuh.nhs.uk

Citing Articles (2)

Citing Articles

1. 1

   Dianne E. Campbell. (2009) Sublingual immunotherapy for children: Are we there yet?. Paediatric Respiratory Reviews 10:2, 69-74
   CrossRef

2. 2

   Qiang-min Xie, Ximei Wu, Hui-min Wu, Yang-mei Deng, Shui-juan Zhang, Jian-ping Zhu, Xin-wei Dong. (2008) Oral administration of allergen extracts from Dermatophagoides farinae desensitizes specific allergen-induced inflammation and airway hyperresponsiveness in rats. International Immunopharmacology 8:12, 1639-1645
   CrossRef