House dust allergy: correlation between in vivo and in vitro diagnostic tests

Two different house dust preparations (house dust and fractionated house dust) were compared using intracutaneous skin tests and RAST assays in 91 patients suspected of house duct sensitivity. Total correlations of 54-64% (house dust) and of 68-74% (fractionated house dust) were obtained. The positive/positive correlations amounted to 52% (n = 66) and to 60% (n = 42) respectively. Seventeen patients were also tested by nasal provocation (NPT) and 33 by bronchial provocation (BPT) using the same house dust extract. Correlations between NPT and skin tests and NPT and RAST were 42% and 47% respectively and between BPT and skin tests and BPT and RAST 56% and 57% respectively.