Eustachian tube obstruction after intranasal challenge with house dust mite

Past studies have shown that provocative intranasal pollen challenge in allergic subjects results in signs and symptoms of allergic rhinitis, nasal obstruction, and eustachian tube obstruction. The study presented herein extends these observations to challenges with a perennial antigen, house dust mite. Twenty-three adult volunteers with confirmed sensitivity to Dermatophagoides farinae were challenged by intranasal inhalation of antigen in doses that were incremented from 0.5 to 10.0 mg. Eustachian tube function by the nine-step pressure-swallow test and nasal airway resistance by anterior rhinomanometry were evaluated before and after challenge. Twenty-two of the 40 ears showing normal tubal function before challenge were abnormal after challenge. Sixteen of the 23 subjects developed a nasal obstruction after challenge. The median specific serum IgE antibody titer for those individuals responding to the challenge was significantly greater than that of the individuals exhibiting no response. These results show that intranasal challenge with D farinae can provoke immune-mediated nasal obstruction and eustachian tube dysfunction in sensitized subjects.