Esophageal dysfunction and immunological changes induced by grass sublingual immunotherapy

Sublingual immunotherapy frequently causes local oropharyngeal adverse events which are usually of mild severity, and tend to be self-limited and disappear within the first weeks of therapy. The mechanism of action involves changes in the specific humoral response to allergens, with increases in allergen-specific immunoglobulin G4 (IgG4) and blunting of the seasonal increase in allergen-specific IgE. We describe the case of a 25-year-old man diagnosed with grass pollen induced allergic rhinoconjunctivitis, who was treated with a lyophilisate of Phleum pratense by sublingual route. After 5 weeks of therapy he developed repeatedly intense symptoms of esophageal dysfunction immediately after the administration. Symptoms recurred every day, subsided in some hours without treatment and disappeared with the termination of therapy. The episode coincided with a marked elevation of total and specific IgE. The immunological changes gradually declined during the three years of follow up. The reported case suggests the need to evaluate the role of the immunological changes detected after the first weeks of sublingual therapy with Phleum pratense, in the induction of esophageal disorders.