Biomedical subjects

Robert C Kern

Publications and source records attributed to Robert C Kern.

21 records · Page 2Linked to original sources

PubMedDate not supplied

Chronic sinusitis with nasal polyps: staphylococcal exotoxin immunoglobulin E and cellular inflammation.

BACKGROUND: The etiology of chronic sinusitis with nasal polyposis (CS/NP) remains enigmatic. Frequently, Staphylococcus aureus is present in the nose of CS/NP patients, although the significance is unclear. Recent reports have suggested the hypothesis that these bacteria may secrete exotoxins triggering the inflammatory mucosal changes seen in CS/NP. This mechanism of immunopathology has been established in other diseases associated with Staphylococcus colonization and exotoxin secretion such as atopic dermatitis. In atopic dermatitis, the exotoxins incite a local superantigen response in which clonal T-cell activation and massive cytokine release occur in the affected skin. Second, these exotoxins can act as traditional allergens, stimulating a typical immunoglobulin E (IgE) response in the serum, which has been correlated with disease severity. This study is designed to begin the assessment of the hypothesis that a similar mechanism takes place in CS/NP. METHODS: Serum was drawn from patients with CS/NP undergoing endoscopic sinus surgery as well as 13 atopic and nonatopic control subjects without sinusitis. IgE levels to S. aureus exotoxins A (SEA), SE exotoxins B (SEB), and toxic shock syndrome toxin 1 were measured using enzyme-linked immunosorbent assay. Tissue eosinophilia and the presence of lymphocytes on hemotoxylin and eosin-stained sections of polyps were scored by a blinded pathologist and correlated to presence of toxin IgE in the serum. RESULTS: Staphylococcal exotoxin (SE)-specific IgE was found in the serum of 5/10 (50%) of the patients with CS/NP. In contrast, 0/13 control patients had IgE to the exotoxins (p = 0.031). Polyp eosinophil, lymphocyte, and mononuclear cell counts were compared in IgE exotoxin-positive and -negative subjects. A trend toward increased eosinophil counts in patients with SE IgE (SE IgE+) was present, but not statistically significant. CONCLUSION: These results indicate that a high percentage of CS/NP patients show a systemic IgE response to S. aureus exotoxins in comparison with controls without CS/NP. Although these results are consistent with the actions of Staphylococcus toxins in other diseases, additional work is necessary to establish a local superantigen response in the nasal mucosa of CS/NP patients.

Adult↗

PubMedDate not supplied

Aeroallergen hypersensitivity: comparing patients with nasal polyps to those with allergic rhinitis.

Immunoglobulin E-mediated allergy generally has not been considered to be important in the pathogenesis of nasal polyps, despite elevated immunoglobulin E in polyp exudates, tissue eosinophilia, and degranulated mast cells. In previous reports, patients with nasal polyps were more likely to have positive skin tests to perennial than to seasonal allergens. It is postulated that nasal polyps result from the constant nature of perennial allergen exposure. The objective of this report is to compare the prevalence of sensitization to six aeroallergens in a group of nasal polyp (NP) patients, a group of allergic rhinitis (AR) patients, and those subjects with positive skin tests in the National Health and Nutrition Examination Survey (NHANES) II. Twenty-five consecutive NP patients evaluated over a 3-month period of time at Northwestern Allergy and Immunology Outpatient Center, in addition to 50 of the allergic rhinitis patients evaluated over the same time, were chosen randomly. All were skin tested with the following antigens: dog, cat, dust mite, grass, tree, and ragweed. Published skin test data from the NHANES II study of 14,367 individuals was obtained also. The percent of NP patients, AR patients, and NHANES II subjects with sensitization to perennial allergens was 72, 96, and 7.6%, respectively. The difference between the AR and NP patients was statistically significant (p = 0.006). The percent of NP, AR, and NHANES II subjects sensitized to seasonal allergens was 84, 86, and 17.7%, respectively. No statistical significance existed between the AR and NP patients, regarding seasonal allergens. Although the AR and NP had similar levels of reactivity to perennial and seasonal allergens, the NHANES II group was more than twice as likely to be sensitized to a seasonal allergen. The NP and AR groups were similar in prevalence of reactivity to seasonal allergens, but the NP patients in our population actually were less likely to be sensitized to perennial allergens than individuals with AR.

Air Pollution↗

PubMedDate not supplied

Long-term effects of FloSeal packing after endoscopic sinus surgery.

BACKGROUND: A previous study by our group showed increased adhesions and granulation tissue in ethmoid cavities packed with FloSeal (FS) compared with those packed with thrombin-soaked gelatin foam after endoscopic sinus surgery (ESS). That study included 20 patients whose cavities were graded 6-8 weeks postoperatively. The goal of this study was to report long-term follow-up on this cohort. METHODS: At least 1 year follow-up was available in 18/20 patients. The number of office procedures required to lyse adhesions during the follow-up period was tabulated also. Pathology was available from one patient who underwent lysis of adhesions on an FS side. The histopathological findings are presented. RESULTS: The mean follow-up period was 21.4 (+/- 2.3) months, and none of the 18 patients required revision ESS during this interval. The overall incidence of adhesions (p = 0.013) and the number requiring lysis of adhesions (p = 0.046) were both greater in the FS group. During the interval between previous study evaluation (6-8 weeks postop) and last follow-up, five FS sides required a total of seven procedures to lyse adhesions. Silent adhesions were observed in an additional five FS sides. Although asymptomatic adhesions were observed in two thrombin-soaked gelatin sides at last examination, none underwent lysis. Biopsy of an adhesion from a patient packed with FS 25 months earlier revealed incorporated foreign material. CONCLUSION: FS appears to be associated with scar tissue formation and may be incorporated into recovering mucosa. Use of FS may increase the degree of postoperative care required after ESS.

Cohort Studies↗