Skin testing and extrinsic allergic alveolitis

Area of Science:

• Immunology
• Pulmonary Medicine
• Allergy

Background:

• Extrinsic allergic alveolitis (EAA) is an immune-mediated lung disease.
• Pigeon fanciers are at risk due to exposure to avian antigens.
• Accurate diagnosis of EAA can be challenging.

Purpose of the Study:

• To evaluate the utility of different skin testing methods for diagnosing EAA in pigeon fanciers.
• To correlate skin test responses with atopy and specific antibody levels.

Main Methods:

• 102 pigeon fanciers underwent skin prick testing with common allergens and avian antigen.
• Intradermal skin testing with avian antigen was also performed.
• Tuberculin testing and serum IgG antibody titers were assessed.

Main Results:

• Prick tests for common allergens showed no difference between EAA patients and controls.
• Immediate reactions to avian antigen via prick test correlated with atopy.
• Intradermal avian antigen testing showed immediate reactions correlating with IgG antibody titers and EAA.
• Late-phase skin reactions (4-6 hours) were highly specific for EAA.
• Tuberculin anergy was associated with higher avian IgG antibody titers.

Conclusions:

• Intradermal skin testing with avian antigen is a valuable tool for diagnosing EAA.
• Late-phase reactions are highly indicative of EAA.
• Skin testing responses, particularly intradermal and late-phase, combined with antibody titers, improve EAA diagnosis in pigeon exposure settings.