Surgical treatment for nasal polyposis: predictors of outcome

Recently, an increasing number of systematic reviews have been published in which the measurement properties of health status questionnaires are compared. For a meaningful comparison, quality criteria for measurement properties are needed. Our aim was to develop quality criteria for design, methods, and outcomes of studies on the development and evaluation of health status questionnaires. Quality criteria for content validity, internal consistency, criterion validity, construct validity, reproducibility, longitudinal validity, responsiveness, floor and ceiling effects, and interpretability were derived from existing guidelines and consensus within our research group. For each measurement property a criterion was defined for a positive, negative, or indeterminate rating, depending on the design, methods, and outcomes of the validation study. Our criteria make a substantial contribution toward defining explicit quality criteria for measurement properties of health status questionnaires. Our criteria can be used in systematic reviews of health status questionnaires, to detect shortcomings and gaps in knowledge of measurement properties, and to design validation studies. The future challenge will be to refine and complete the criteria and to reach broad consensus, especially on quality criteria for good measurement properties.

Approximately 85% of nasal polyps (NPs) in white subjects are characterized by prominent eosinophilia. IL-5 is the key driver of eosinophilic differentiation and survival. We sought to investigate the therapeutic potential of inhibiting IL-5 with a humanized mAb as treatment for severe nasal polyposis. Thirty patients with severe nasal polyposis (grade 3 or 4 or recurrent after surgery) refractory to corticosteroid therapy were randomized in a double-blind fashion to receive either 2 single intravenous injections (28 days apart) of 750 mg of mepolizumab (n = 20) or placebo (n = 10). Change from baseline in NP score was assessed monthly until 1 month after the last dose (week 8). Computed tomographic scans were also performed at week 8. Twelve of 20 patients receiving mepolizumab had a significantly improved NP score and computed tomographic scan score compared with 1 of 10 patients receiving placebo at week 8 versus baseline. Mepolizumab achieved a statistically significant reduction in NP size for at least 1 month after dosing in 12 of 20 patients. IL-5 inhibition is a potential novel therapeutic approach in patients with severe eosinophilic nasal polyposis. Copyright © 2011 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Nasal polyps (NPs) are characterized by eosinophilic inflammation and often coexist with asthma. However, the role of atopy and IgE in NP pathogenesis is unclear. We sought to determine whether there is an association between total and specific IgE to a variety of allergens in polyp and nonpolyp tissue and markers of eosinophilic inflammation or skin test results. Homogenates were prepared from nasal tissue of 20 patients with NPs and 20 patients without NPs and analyzed for concentrations of IL-5, IL-4, eotaxin, leukotriene (LT) C4/D4/E4, sCD23, and histamine (ELISA). Eosinophil cationic protein (ECP), tryptase, and total and specific IgE for inhalant allergens and Staphylococcus aureus enterotoxins were measured (ImmunoCAP). The concentrations of total IgE, IL-5, eotaxin, ECP, LTC4/D4/E4, and sCD23 were significantly higher in NP tissue compared with nonpolyp tissue. Total IgE was significantly correlated to IL-5, ECP, LTC4/D4/E4, and sCD23 and to the number of eosinophils in NPs. On the basis of the presence of specific IgE antibodies in tissue, 3 NP groups were defined. NP group 1 demonstrated no measurable specific IgE, and NP group 2 selected specific IgE. The third group demonstrated a multiclonal specific IgE, including IgE to S aureus enterotoxins, a high total IgE level, and a high prevalence of asthma. These studies suggest that there is an association between increased levels of total IgE, specific IgE, and eosinophilic inflammation in NPs, which may be of relevance in the pathophysiology of nasal polyposis. Similarly, the presence of specific IgE to staphylococcal enterotoxins A and B also points to a possible role of bacterial superantigens.