Mite hypersensitivity in patients with rhinitis and rhinosinusitis living in a tropical environment

Area of Science:

• Allergy and Immunology
• Environmental Health
• Tropical Medicine

Background:

• Rhinitis and rhinosinusitis are significant public health issues, particularly in tropical regions where mites are prevalent etiological agents.
• Understanding the specific allergens triggering these conditions is crucial for effective management and public health strategies.

Purpose of the Study:

• To investigate the in vivo immune response to various mite allergens in patients diagnosed with rhinitis and rhinosinusitis.
• To determine the prevalence of sensitization to different inhalant allergens, with a focus on mites, in patients attending allergy clinics.

Main Methods:

• Inclusion of all patients presenting with presumptive nasal allergy symptoms.
• Performance of skin prick tests using a range of inhalant allergens, including specific mite extracts.
• Classification of patients into allergic or non-allergic groups based on skin test results and clinical history.

Main Results:

• Out of 229 patients, 76.4% exhibited positive skin test reactions to inhalant allergens.
• Allergic patients demonstrated high sensitization rates to mites, with Dermatophagoides species (D. farinae and D. pteronyssinus) showing over 90% positivity.
• Significant cross-reactivity was observed among mite allergens from the same taxonomic family, suggesting shared allergenic epitopes.

Conclusions:

• Mites are confirmed as the predominant cause of respiratory allergies in tropical environments, impacting a substantial majority of patients with rhinitis or rhinosinusitis.
• The findings suggest that cross-reactivity to mite allergens, even those not endemic to the local environment, plays a critical role in positive skin test results and allergic responses.