Intradermal immunotherapy with low-dose house dust mite allergens in patients with allergic rhinitis: A proof-of-concept study

Background: High-dose aqueous subcutaneous immunotherapy is a validated and effective administration route for house dust mite and pollen allergens. Objective: A proof-of-concept study using intradermal immunotherapy (IDIT) with low-dose house dust mite allergens (Dermatophagoides pteronyssinnus/Dermatophagoides farinae [Dp/Df] and Blomia tropicalis [Bt]) was carried out in children with allergic rhinitis symptomatic upon exposure to house dust. Methods: Eight immunotherapy-naïve patients with positive prick skin tests and specific serum IgE to a Dp/Df mixture and to Bt were weekly administered 0.05 mL of an IDIT consisting of a phenolyzed albumin-saline preparation containing low-dose dust mites (8.3 AU [5 ng] of Dp/Df and 2.5 DBU of Bt), for 3 months. Nasal (Total Nasal Symptom Score) and facial symptoms (Visual Analog Scale) were recorded 2 weeks prior to treatment and once weekly during its course. Serial dilutions skin prick tests (1/100-1/1.000.000) and serum allergen-specific IgG4 determinations were performed at baseline and at treatment conclusion. Results: Values on the scales suggested clinical improvement. There was a significant decrease in serial dilutions skin prick tests’ wheal diameters, as well as an increase in serum IgG4 values at treatment completion. IDIT was well tolerated. Conclusion:If the present results are confirmed by further studies, allergen-specific immunotherapy wider use could be promoted.