NASAL POLYPS - EFFECTS OF SEASONAL ALLERGEN EXPOSURE

Nasal polyps are characterized by chronic eosinophilic inflammation an d often coexist with rhinitis and asthma. Many patients with polyps ha ve no detectable allergy, and it is considered that allergy, at least in many cases, is not relevant to polyp pathogenesis. To explore the a ssociation of nasal polyps with allergy, 16 patients with polyps and r agweed allergy (PRW+) and 16 patients with polyps who were not allergi c to ragweed (PRW-) were compared with patients without polyps, 16 who were allergic to ragweed (NPRW+) and 16 who were not allergic to ragw eed (NPRW-), before and during the ragweed season. The level of ragwee d allergy was comparable in the PRW+ and NPRW+ populations as determin ed by ragweed skin test wheal diameter, ragweed IgE RAST percent bindi ng, and total serum IgE. Symptom scores before the ragweed season reco rded on visual analog scales for the symptoms of blockage, sneezing, d ecreased smell, itch, postnasal drip, and runny nose were high in pati ents in the PRW+ and PRW- groups and did not change during ragweed sea son. Mean symptom scores were low in the NPRW+ group before ragweed se ason and increased during the season to levels similar to those of pat ients in the PRW+ and PRW- groups. Preseason nasal lavage albumin conc entration was higher in subjects with polyps than those without polyps (58.5, 98) versus (13.6, 15 mug/ml) (p = 0.02) and did not change sig nificantly in any group with seasonal exposure. Data are presented as mean, 1 SD; comparisons are made with unpaired t tests. The preseason percent eosinophils in the nasal irrigation fluid was higher in the su bjects with polyps than in subjects without polyps (18, 25) versus (0. 9, 2%), (p = 0.0002) and changed little for patients in the PRW+ group during ragweed season. In the NPRW+ group the percent eosinophils inc reased greatly from low preseason counts, (comparison made with paired t test) (2.2%) to 28, 33% (p = 0.02), the latter comparable to those of subjects with polyps. The nasal lavage eosinophil cationic protein concentration out of season was higher in subjects with polyps than in those without polyps (9.7, 10) versus (1.4, 1.0) (p = 0. 0001) and di d not change in subjects with polyps during seasonal exposure. Nasal r esistance was measured by head-out body plethysmography. It was slight ly higher in subjects with polyps than in those without polyps out of season. In conclusion, highly ragweed-allergic patients with polyps ha d symptoms and elevated markers of nasal mucosal inflammation (percent eosinophils and eosinophil cationic protein and albumin concentration s) out of season, and these did not increase in relation to natural se asonal allergen exposure. Ragweed allergic subjects with no polyps had large seasonal increases in symptoms and nasal irrigation fluid perce nt eosinophils. We conclude that ongoing conditions, perhaps nasal air way mucosal inflammation, in nasal polyposis may lead to a loss of sus ceptibility to potential additional effects of inhaled allergen.