Prevention of relapses of nasal polyposis with intranasal triamcinolone acetonide after polyp surgery: a prospective double-blind, placebo-controlled, randomised study with a 9-month follow-up.

OBJECTIVE: To determine whether intranasal triamcinolone acetonide prevents the regrowth of nasal polyps after polyp surgery. STUDY DESIGN: Randomised, double-blind, placebo-controlled, prospective study. SETTING: Helsinki University Central Hospital. PARTICIPANTS: Sixty patients with nasal polyps entered the study. Patients were included upon arrival for elective polyp operations determined according to our standard clinical criteria. The recurrence of nasal polyposis was followed up for 9 months after surgical treatment at 3-month intervals. MAIN OUTCOME MEASURES: Anterior rhinoscopy, nasal endoscopy, olfactory threshold measurement, active anterior rhinomanometry and acoustic rhinometry were performed at every follow-up visit. RESULTS: On the whole, there was a significant inter-group difference in the change in polyp size of acetylsalicylic acid (ASA)-tolerant patients during the follow-up. In patients with acetylsalicylic acid intolerance, there was no inter-group difference (P = 0.28). No significant differences were noted for nasal resistance, nasal cavity volume, sense of smell and nasal symptoms. CONCLUSION: Triamcinolone acetonide prevents regrowth of nasal polyps after polyp surgery in acetylsalicylic acid-tolerant patients, but not in acetylsalicylic acid-intolerant patients.

Selectivity of IgE responses, mast cell sensitization, and cytokine expression in the immune response of Brown Norway rats to chemical allergens.

Sensitizing chemicals can induce various types of allergic disease, including contact dermatitis and occupational asthma. In the present study we have examined the nature of the immune response induced in Brown Norway (BN) rats by oxazolone (OX), a potent contact allergen, and by trimellitic anhydride (TMA), a chemical known to cause sensitization of the respiratory tract and occupational asthma. BN rats were exposed topically to either OX or TMA at doses selected to achieve similar levels of proliferative activity by draining LNC. Both chemicals stimulated hapten-specific IgG antibody responses, but only TMA induced specific IgE antibody, an increase in total serum IgE and active sensitization of mast cells. Draining LNC from OX-treated rats expressed elevated IFN-gamma mRNA, whereas those from TMA-treated rats expressed elevated IL-5 mRNA compared to controls. Furthermore, Con A-activated draining LNC from rats exposed to TMA, but not OX, released significantly increased concentrations of IL-4. In conclusion, different chemical allergens can induce in the BN rat divergent patterns of IgE response and cytokine expression.