Usefulness of nasal provocation tests in occupational rhinitis.

Objective: The aim of the study was to determine whether Nasal Provocation Tests (NPT) could help in the diagnosis of occupational rhinitis (OR).
Methods: Changes in nasal airway resistance (NAR), measured by posterior rhinomanometry during specific nasal challenge associated with per and post test clinical scores, were compared to a prior probability, based on the patient's history, determined by occupational physicians, in 41 hairdressers and 33 bakers referred for suspected OR.
Results: A DeltaNAR >or= 150% defined the positivity of the NPT. DeltaNAR demonstrated 50% sensitivity and a 86% specificity in hairdressers and a 95% sensitivity with 100 % specificity in bakers. DeltaNAR presented significant positive correlations with both per (p = 0.0003, r = 0.48) and post test clinical scores (p < 0.005, r = 0.39). The addition of clinical scores increased the sensitivity to 100% in hairdressers with 81% specificity.
Conclusions: The NPT constitutes a safe procedure of nasal reactivity with good levels of sensitivity and specificity in both hairdressers and bakers when nasal resistance and clinical scores are taken into account.