investigations
Last reviewed 10/2020
- serum IgE levels - elevated secondary to loss of suppressor lymphocyte activity
- skin prick tests - positive to common allergens
- Radioallergosorbent testing (RAST) - suggest that IgE is synthesised against the specific antigens of the house dust mite, pollens, cat and dog hair, food allergens
- skin biopsy reveals chronic inflammation involving lymphocytes, mast cells, histiocytes, eosinophil degranulation
- white dermographism - rubbing skin elicits a simple white linear streak along the site of pressure with no erythema