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Prevalence of nasal polyps in adults: the Skövde population-based study.

Patients with nasal polyps present repeatedly in otorhinolaryngology practices, but the prevalence of nasal polyps in the general population is not known. Our objective was to investigate the prevalence of nasal polyps in an adult Swedish population in relation to age, gender, asthma, and aspirin intolerance. A random sample of 1,900 inhabitants over the age of 20 years, stratified for age and gender, was drawn from the municipal population register in Skövde, Sweden, in December 2000. The subjects were called to clinical visits that included questions about rhinitis, asthma, and aspirin intolerance and examination by nasal endoscopy. In total, 1,387 volunteers (73% of the sample) were investigated. The sample size was adequate, with a good fit to the whole population. The prevalence of nasal polyps was 2.7% (95% confidence interval, 1.9-3.5), and polyps were more frequent in men (2.2 to 1), the elderly (5% at > or = 60 years of age), and asthmatics. Subjective symptoms of aspirin intolerance were not found to correlate with polyps. Nasal polyps were more common in adults than was stated by the a priori estimate. The Skövde population-based study is considered representative for the Swedish population.

Adult↗

Characterization of the eosinophil chemokine RANTES in nasal polyps.

Previous studies have demonstrated that the cytokine RANTES (Regulated And Normal T cell Expressed and Secreted) has been shown to be a potent mediator of eosinophil chemotaxis in vitro and of leukocyte recruitment. Because eosinophils are the hallmark cells in nasal polyposis, we hypothesize that RANTES is locally produced within the nasal polyp microenvironment and is responsible for the eosinophil recruitment seen in nasal polyposis. To begin to test this hypothesis, we evaluated nasal polyps from 17 patients and 3 control specimens for distribution and content of RANTES using immunohistochemical techniques and enzyme-linked immunosorbent assay technology. Our immunohistochemical studies demonstrated that in nasal polyposis, RANTES antigen staining occurred predominantly within eosinophils and epithelial cells. To quantify the relative levels of RANTES in normal and nasal polyp specimens, tissue homogenates were prepared, quantified, and normalized to protein levels. We detected RANTES in all 17 nasal polyp tissue homogenates (566 +/- 16 pg/mg total protein). The RANTES levels in nasal polyp homogenates were nearly 40-fold higher than the RANTES levels in normal tissue (15.7 +/- 28.2 pg/mg total protein). Thus, it appears that increased expression of RANTES by eosinophils and epithelial cells within the nasal polyp microenvironment promotes eosinophil recruitment and activation within nasal polyps. We hypothesize that RANTES induces increased recruitment and activation of eosinophils, presumably contributing to the increased tissue changes associated with nasal polyposis.

Adult↗

Distribution of rantes and interleukin-5 in allergic nasal mucosa and nasal polyps.

Eosinophil-chemoattracting cytokines are thought to be important in the pathogenesis of allergic inflammation. However, little is known about the presence and significance of RANTES in nasal allergy and nasal polyps, two well-known rhinologic disorders characterized by eosinophil infiltration in the tissue. In order to evaluate the role of RANTES in eosinophil infiltration in vivo, the tissue distributions of RANTES and interleukin-5 (IL-5) and their correlation with eosinophil infiltration were investigated. Nasal mucosa specimens were obtained from 9 allergic and 12 control subjects, and nasal polyps from 6 allergic and 9 nonallergic subjects. All the subjects were divided into 4 groups: normal mucosa, allergic mucosa, nonallergic polyps, and allergic polyps. To identify the cellular localizations of RANTES and IL-5, we used specific immunohistochemical staining. We also investigated the differences in cytokine expression among the 4 groups, and the correlation between cytokine expression and eosinophil infiltration in the tissue. RANTES was expressed in the epithelium, endothelium, and some submucosal cells, while IL-5 was confined to the cells in the submucosa. Expression of both RANTES and IL-5 significantly increased in allergic mucosa and nasal polyps compared to normal mucosa; however, there was no significant difference in their expression between allergic and nonallergic polyps. Both cytokines had a significant correlation between their expression and either total or activated eosinophil numbers. The results of this study suggest that RANTES, as well as IL-5, plays a role in eosinophil recruitment in allergic nasal mucosa and nasal polyps in vivo.

Antibodies, Monoclonal↗

The analysis of RCAS1 and DFF-45 expression in nasal polyps with respect to immune cells infiltration.

BACKGROUND: Nasal polyp constitutes a benign growth process in the nasal and sinus mucosa. RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is a protein expressed mainly by various human cancer cells. It is not only the marker of cancer process and its expression can also be observed in physiological processes. It is responsible for the regulation of immune cells activity. DFF45 (DNA fragmenting factor) has been described as a substrate for caspase-3. DFF45 seems to play an important role in the onset of apoptotic process by acting probably through the regulation of DNA fragmentation. The aim of the study was to evaluate the ability of nasal polyps to regulate the cytotoxic immune response and to determine their resistance to apoptosis. RESULTS: The higher RCAS1 level was identified in lymphocytic nasal polyps, the medium one in eosinophilic while the lowest was identified in neutrophilic. DFF-45 expression was higher in eosinophilic than in neutrophilic and lymphocytic nasal polyps. CONCLUSION: The changes in DFF-45 level in nasal polyps might indicate a different resistance to apoptosis mediated by immune cells. The alterations in RCAS1 expression indicate that nasal polyps have the ability to regulate the cytotoxic immune response. The breaking of resistance to immune mediated apoptosis in nasal polyps might have a new therapeutic impact.

Adult↗

The prevalence of colonic polyps in acromegaly: a colonoscopic and pathological study in 103 patients.

Patients with acromegaly are reported to be at risk of developing adenomatous colonic polyps, which are considered to be preneoplastic lesions. This assumption is, however, usually drawn from results obtained in rather small series of patients or without a control group. We, therefore, undertook a prospective colonoscopic and pathological study comprising 103 acromegalic patients and 138 nonacromegalic control subjects referred for irritable bowel syndrome. The prevalence of adenomatous colonic polyps was significantly increased in acromegalic patients compared to that in control subjects (22.3% vs. 8.0%; P = 0.0024). The significance was similarly present in male acromegalic patients (28.6% vs. 5.5% in male control subjects; P = 0.0026), but was absent in female acromegalic patients. The prevalence of colonic polyps was also significantly increased in the group of acromegalic patients under 55 yr of age (20.0% vs. 3.0% in the control group of the same age; P = 0.0026). Other characteristics of adenomatous colonic polyps in acromegaly were the multiplicity and the presence proximal to the splenic flexure. No difference in the duration of acromegaly was found between patients with or without adenomatous polyps. The prevalence of hyperplastic colonic polyps was also significantly increased to 24.3% in acromegalic patients vs 4.4% in control subjects (P < 0.001). In conclusion, in view of the increased incidence of adenomatous colonic polyps, colonoscopy should be part of the follow-up examination in acromegaly.

Acromegaly↗

Exercise and intestinal polyp development in APCMin mice.

PURPOSE: Epidemiological evidence suggests that physical activity protects against colon cancer. We previously used a mouse predisposed to intestinal polyps (APCMin) to evaluate this association and found the suggestion of fewer polyps in exercised males but not females. The present study was designed to further explore the potential exercise x sex interaction on polyp development and to begin to look at potential mechanisms. METHODS: Six-week-old APCMin mice (N = 60 males; 60 females) were randomly assigned to one of two groups by sex: treadmill running at 20 m.min-1, 5% grade, 45 min.d-1, 5 d.wk-1 (EX) or nonrunning controls (CON) (N = 30 per group). EX mice ran in running wheels while in quarantine (weeks 0-3), followed by treadmill running weeks 3-8. Body weights were measured weekly. Urine was collected at 5 wk and fasting blood at 7.5 wk. Body composition was measured, serum was frozen, and polyp number and size were measured at sacrifice. RESULTS: EX resulted in lower body weights (P < 0.01) and reduced fat mass (P < 0.01). Fasting glucose was lower in EX (P < 0.01), and leptin was lower in EX (P = 0.05) compared with CON. EX did not affect serum insulin-like growth factor-1 or urinary corticosterone. Total polyp number and size were not statistically different between groups; however, there were fewer jejunal polyps in EX (3.6 +/- 0.7, mean +/- SE) versus CON males (5.2 +/- 0.8; P = 0.04) and an even larger difference when only the consistent runners were kept in the analysis (2.7 +/- 0.5 in EX; P = 0.01). CONCLUSION: Despite favorable changes in body composition, blood glucose, and leptin, 8 wk of running resulted in only minor changes related to polyp development in male but not female APCMin mice.

Animals↗

Antrochoanal polyp and obstructive sleep apnoea in children.

Antrochoanal polyps were first documented in the 18th century. They represent one of the most common types of nasal polyps in children without cystic fibrosis. Only a few reports on children who had a history of snoring due to an antrochoanal polyp and only two cases where the antrochoanal polyp caused documented obstructive sleep apnoea (OSA) have been published so far. This report adds a third case of paediatric OSA induced by an antrochoanal polyp in a 12-year-old boy. After endonasal endoscopically-controlled polypectomy and a recurrence, transoral osteoplastic antrotomy in combination with endoscopic endonasal polypectomy eliminated the antrochoanal polyp and OSA was resolved. The authors have reviewed essential historical aspects about children suffering from snoring and/or OSA caused by an antrochoanal polyp.

Child↗

To step or not to step: an approach to clinically diagnosed polyps with no initial pathologic finding.

We determined whether there were additional diagnostic findings in additional level sections performed on polyps with no pathologic diagnosis (NPD) or those in which only lymphoid aggregates (LAs) were seen initially and determined the level at which findings were identified. All colorectal biopsy specimens submitted with a clinical diagnosis of polyp during a 6-month period were included (N = 733). Initially, 3 level sections were cut for each polyp, and if a cause for the polyp was found, no additional levels were evaluated. If LAs or no cause for the polyp was found, 5 additional levels through each block were examined. Any diagnostic findings and the level at which they were identified were recorded. A discrete cause for the polyp was identified in routine levels in 574 cases (78.3%). Deeper levels were performed in 159: 23 for clarification of a suspected diagnosis, 38 for LAs, and 98 for NPD. Findings were identified in 31 (22.8%) of 136 stepped for LA or NPD with neoplastic findings in 13 (9.6%). Most diagnoses were identified in levels 4 or 5, but tubular adenomas were found in levels 7 and 8. These results support level sectioning specimens submitted as polyps with NPD or LAs on initial sections.

Adenoma↗

Endoscopic gastric polypectomy using high frequency current: its significance for total biopsy of gastric polyp.

Endoscopic polypectomy using high frequency current was performed for 281 out of 345 gastric polyps (230 cases), while the remaining 64 small polyps were cauterized. Histopathologic examinations carried out in 274 out of the 281 polypectomized polyps confirmed gastritis polyposa in 41 lesions, hyperplastic polyps in 216 including 3 cases of neoplasm, atypical epithelium in 4, submucosal tumor in 2, and polypoid cancer in 1. This procedure of endoscopic polypectomy has proved to enable histologic examination of a polyp as a whole, and to allow a highly risk-free endoscopic treatment of polyps. In the currently observed 216 hyperplastic polyps, 3(1.4%) were found to have neoplastic changes.

Endoscopy↗

Detectability of small and flat polyps in MDCT colonography using 2D and 3D imaging tools: results from a phantom study.

OBJECTIVE: The objective of this phantom study was to determine the performance of MDCT colonography for the detection of small polyps under ideal imaging conditions and to determine the added value of 3D imaging when used as an adjunct to 2D imaging. MATERIALS AND METHODS: Thirty-six polypoid and 39 flat polyps (44 lesions, 2-5 mm; 31 lesions, 6-8 mm) were placed in three explanted segments of a thoroughly cleaned porcine colon (overall length, 4.5 m) that was distended with air and submerged in a water phantom. MDCT data sets with 4 x 1 mm collimation and 6-mm table feed were reconstructed every 0.7 mm with 1.25-mm effective slice width. The data were reviewed by three radiologists using 2D images in all three projections and with 3D volume-rendered images available as an adjunct to the 2D images. RESULTS: Additional 3D as a problem-solving tool significantly increased the overall sensitivity (96% vs 90%), decreased the total number of false-positive calls (n = 9 vs n = 5), and increased the diagnostic confidence level (p < 0.03) compared with 2D images alone. Small polyps less than or equal to 5 mm (89% vs 95%, p = 0.004) and flat polyps (82% vs 94%, p = 0.001) especially benefited from 3D. Sensitivity was generally higher for polypoid than for flat polyps (99% vs 94%, p = 0.041). CONCLUSION: Under phantom conditions, simulating an ideal clinical setup, MDCT colonography is not limited by spatial resolution and detects polyps less than or equal to 5 mm in size with high sensitivity and specificity. Additional 3D image tools improve diagnostic accuracy and reviewer confidence, especially for the detection of flat and small polyps.

Animals↗

Recurring hyperplastic gastric polyps following subtotal gastrectomy.

Mucosal polyps of the stomach are separated by histologic means into two major groups: (1) hyperplastic (or regenerative) polyps and (2) adenomas, including adenomatous polyps and villous adenoma. Hyperplastic polyps are not true neoplasms, but probably represent a reactive response to some form of mucosal injury. A little known but interesting manifestation of hyperplastic gastric polyps concerns their development, growth, and recurrence in the gastric remnant following subtotal gastrectomy. The clinical, radiologic, and pathologic findings in two cases of recurring symptomatic hyperplastic gastric polyps after subtotal gastrectomy are presented. It is proposed that reflux bile gastritis might have played an important etiologic role in the development of these recurring hyperplastic polyps.

Adult↗

Atypical appearances of benign hyperplastic gastric polyps.

The vast majority of epithelial polyps of the stomach can be divided into two groups: (1) hyperplastic or regenerative polyps, and (2) adenomas. Of the two, hyperplastic polyps are much more common; they are nonneoplastic lesions which are typically asymptomatic, small, smooth-surfaced, and often multiple. Malignant transformation virtually never occurs in this group of polyps. Adenomas are true neoplasms; they are relatively large, have an irregular surface, and show a distinct tendency to undergo malignant transformation. In this paper the radiologic appearances of hyperplastic gastric polyps, with special reference to atypical findings, are discussed and illustrated. It is shown that simple hyperplastic polyps may present any or all of the radiologic criteria suggestive of gastric adenomas or even frank malignancy. Thus, while radiology plays a vital role in the initial detection and followup of gastric polyps, optimum clinical management of the patient is best based on knowledge of the histologic structure of the lesion obtained by endoscopy and biopsy.

Aged↗

The fluoroscopic barium enema in colonic polyp detection.

The results of 1,500 barium enema studies done by vigorous manual palpation under fluoroscopy were reviewed to determine the adequacy of this technique in detecting polyps above the proctoscopic level. Of the 1,500 patients examined, 103 (7%) were diagnosed radiographically as having a total of 149 polyps. Polyps were found at proctoscopy in about 10% of the 1,500 patients. Colonoscopy or surgery was performed on 35 of the 103 patients. Of the 52 polyps discovered during these procedures, only three were missed at fluoroscopic barium enema study, a false-negative rate of 6%. Fourteen patients whose barium enemas initially were reported as negative for polyps or neoplasia had colonoscopy. Two of the 14 patients had positive findings, for a true-negative rate of 86%. If the detection rate of 7% found at barium enema, taking into account an overlap of 10%, is combined with the rate of 7.5% found at proctoscopy, a frequency of about 14% emerges in detecting polyps in the rectum and in the colon. Thus, the fluoroscopic barium enema when combined with proctoscopy is a sensitive method in the detection of colorectal polyps. In addition, it has the advantage of rapid execution and relatively low cost.

Barium Sulfate↗

Single-contrast vs double-contrast barium enema in the detection of colonic polyps.

Radiographic and colonoscopic correlation in 139 patients with 234 colonic polyps compared the sensitivity of single- and double-contrast barium enema. Single-contrast barium enema detected 68 (80%) of polyps, with 72% of polyps under 1 cm and 94% of those 1 cm or over detected. Double-contrast barium enema detected 135 (91%) of 149 polyps, with 88% of polyps under 1 cm and 96% of larger polyps detected. Thus, the double-contrast barium enema was more effective than the single-contrast examination only for detection of polyps under 1 cm. The single-contrast barium enema was more likely performed on patients in poor physical condition and in those over 70 years old. The results suggest that for elderly patients, who may have difficulty in cooperating for a double-contrast enema, a properly performed single-contrast examination is an acceptable option.

Adenoma↗

CT colonography with three-dimensional problem solving for detection of colonic polyps.

OBJECTIVE: We performed CT colonography in patients referred for conventional colonoscopy, interpreted the axial images, and used commercially available software to reconstruct endoluminal perspective views to differentiate polyps from folds. SUBJECTS AND METHODS: We prospectively examined 44 patients (27 men and 17 women; mean age, 58 years old) with CT colonography by interpreting the axial images and using three-dimensional rendering for problem solving only. The CT scans were interpreted by two radiologists who were unaware of patients' histories as revealed by colonoscopic findings. The findings on colonography were compared with those of conventional colonoscopy to determine sensitivity, specificity, time spent on interpretation, and confidence of interpretation. RESULTS: Colonoscopy showed normal findings in 28 patients and 22 polyps in the remaining 16 patients. Six polyps were 8 mm or larger, three were 5-7 mm, and 13 were 5 mm or smaller. The findings of the two observers revealed an overall sensitivity of 50% and 38%, respectively, and a specificity of 93% and 86%, respectively. Sensitivity for polyps larger than 8 mm was 83% and specificity was 100% for both observers. The average amount of time spent on interpretation was 28 min 30 sec (range, 14-65 min). Both observers used the endoluminal view for differentiating folds from polyps in 23 (52%) of 44 patients, which had only minimal impact on interpretation time. CONCLUSION: CT colonography can be performed and the images interpreted using currently available hardware and software by initially using the axial images to search for polyps of significant size. Endoluminal views should be used only when necessary to help distinguish normal folds from fixed raised lesions that are suggestive of polyps.

Colonic Polyps↗

Graded compression sonography of the colon in the diagnosis of polyps in pediatric patients.

OBJECTIVE: We report seven cases of juvenile polyps detected by graded compression gray-scale and color Doppler sonography in five children with nonspecific symptoms. CONCLUSION: Intestinal polyps can be detected by graded compression gray-scale and color Doppler sonography without colonic preparation. On gray-scale sonography, polyps appeared as spherical or ovoid hypoechoic nodules in the colon lumen. Small cysts were identified inside the nodules. Four polyps had fewer and smaller cysts, whereas three others contained many cysts. A hyperechoic layer surrounding the polyp corresponded to the submucosa. In two patients, the polyp was visualized in the transverse colon and caused a colocolic intussusception, which reduced spontaneously during sonography. Color Doppler sonography showed four hypovascularized and three hypervascularized polyps.

Age Factors↗

Nasal polyps: relationship to infection and inflammation.

Because no single predisposing disease can account for the formation of nasal polyps in all patients, medical and surgical therapy has to be directed toward the inflammatory process and/or the underlying infection, together with the development of local tissue pathology. Light and electron microscopical studies in experimental models have revealed that the initial polyp formation sequence involves multiple epithelial disruptions with proliferating granulation tissue, where immature branching epithelium migrates to cover the mucosal defect. Other branches spread into the underlying connective tissue, where intraepithelial microcavities with a differentiated epithelial lining separate the developing polyp body from the adjacent mucosa. Polyp formation and growth is thus activated and perpetuated by an integrated process of mucosal epithelium, matrix, and inflammatory cells, which in turn may be initiated by both infectious and noninfectious inflammation. Glucocorticosteroids display a favorable therapeutic profile, directly preventing both polyp formation and polyp growth, but also by reducing local pathology and inflammatory exudate with bacterial colonization. Steroids often combined with antibiotics or surgery aimed at specific events in polyp development have to be used in relation to disease progression, and severity as well as differences in clinical behavior due to the multifactorial pathophysiological events of nasal polyposis.

Animals↗

Superantigens and chronic rhinosinusitis: skewing of T-cell receptor V beta-distributions in polyp-derived CD4+ and CD8+ T cells.

BACKGROUND: Recent studies have suggested that Staphylococcus aureus secrete superantigenic toxins that play a role in the etiology of chronic rhinosinusitis with nasal polyposis (CRSwNP). Twenty S. aureus superantigens (SAg's) have been identified, each of which bind the V beta-region of the T-cell receptor (TCR) outside the peptide-binding site. Approximately 50 distinct V beta-domains exist in the human repertoire, and distinct SAg's will bind only particular domains generating a pattern of V beta-enrichment in lymphocytes dependent on the binding characteristics of a given toxin. The aim of this study was to analyze the pattern of V beta-expression in polyp-derived lymphocytes from CRSwNP patients. METHODS: Polyps were harvested from 20 patients with CRSwNP and 3 patients with antrochoanal polyps. Flow cytometry was used to analyze the V beta-repertoire of polyp-derived CD4+ and CD8+ lymphocytes. Data were analyzed in light of the known skewing associated with SAg exposure in vivo and in vitro. Skewing was defined as a percentage of V beta-expression >2 SD of that seen in normal blood. RESULTS: Seven of 20 subjects exhibited skewing in V beta-domains with strong associations with S. aureus SAg's. The three antrochoanal polyps failed to show any significant V beta-skewing. CONCLUSION: This study establishes evidence of S. aureus SAg-T-cell interactions in polyp lymphocytes of 35% of CRSwNP patients. Although these results are consistent with intranasal exposure of polyp lymphocytes to SAg's, additional study is necessary to establish the role of these toxins in disease pathogenesis.

CD4-Positive T-Lymphocytes↗