Update on nasal polyps: etiopathogenesis.

PURPOSE OF REVIEW: Nasal polyps is a common ENT disease with high medical failure and recurrence rate, reflecting unknown pathogenesis. The present review is an update on the etiopathogenesis of nasal polyps. RECENT FINDING: Several mechanisms have been proposed for the formation of nasal polyps, including allergy, mucosal allergy, autonomic imbalance, nitric oxide, superantigens, infection, abnormal transepithelial ion transport, mucopolysaccharide abnormality, mechanical obstruction and epithelial rupture. Eosinophils comprises more than 60% of the cell population. Activated T cells, mast cells and plasma cells are also increased compared with the normal nasal mucosa. The stroma has numerous mediators, including cytokines, growth factors, adhesion molecules, and immunoglobulins. Both Th1 and Th2 types of cytokines are upregulated independent of the atopic status. An increased production of GM-CSF, IL5, RANTES and eotaxin can contribute to chronic eosinophilic inflammation by regulating the migration, survival and activation of eosinophils. CONCLUSION: Nasal polyps is a multifactorial disease, with infectious, noninfectious, inflammation, anatomic and genetic abnormalities. Chronic inflammation remains the central major factor in nasal polyps.

A comparison between endoscopically middle meatal aspiration culture using modified aspiration instrument and direct maxillary antral tap culture in chronic rhinosinusitis.

OBJECTIVES: To evaluate the accuracy of endoscopically guided middle meatal aspiration culture by comparing the culture results between middle meatal aspiration using the modified aspiration instrument and direct maxillary antral tap. MATERIAL AND METHOD: Sixteen patients with chronic rhinosinusitis underwent functional endoscopic sinus surgery (FESS) were enrolled. Both endoscopically middle meatal aspiration culture (EMAC) using modified aspiration instrument and direct antral tap culture (ATC) were performed before FESS. Microbiologic data were compared and analyzed for any statistical differences between EMAC and ATC. RESULTS: The positive culture rates were 93.75% in both EMAC and ATC groups. Aerobic and facultative anaerobic bacteria were found in 87.5% of EMAC group and 81.25% of ATC group. The two most common bacteria in both groups were coagulase-negative Staphylococcus and Staphylococcus aureus. The association between EMAC and ATC was strong to moderate (13/16) 81.25%. CONCLUSION: EMAC appears to be a valuable alternative to ATC for guiding bacterial-specific therapy in chronic rhinosinusitis. This modified aspiration instrument should be useful in clinical practice and serve as a cost effective procedure.

Nasal polyps: the relationship to allergy, sinonasal infection and histopathological type.

OBJECTIVE: To evaluate the relationship of nasal polyps to allergy, sinonasal infection and histopathological type by examining the prevalences of these factors among nasal polyps patients. STUDY DESIGN: Prospective descriptive study. MATERIAL AND METHOD: A total of 73 patients were enrolled between October 1st, 1999 and August 31st, 2002 at the Allergy and Rhinology Clinic, Faculty of Medicine, Songklanagarind Hospital. The medical history was recorded. Allergy skin prick test, nasal endoscopy with biopsy and plain film paranasal sinus were performed. Positive allergy skin test was defined by at least 1 aeroallergen with a wheal size > or = 3 mm greater than the negative control. Rhinosinusitis was diagnosed by clinical symptoms, positive nasal endoscopy and/or positive plain film paranasal sinus. Histopathological investigation was classified as eosinophil- or neutrophil-dominated inflammation. RESULTS: 68.5 per cent of patients with nasal polyps had a positive allergy skin test, 67.1 per cent had rhinosinusitis. Eosinophil-dominated inflammation was presented in 69.9 per cent and neutrophil-dominated inflammation in 30.1 per cent, respectively. Within each histopathological type, 62.7 per cent of patients with eosinophil-dominated inflammation and 81.8 per cent of patients with neutrophil-dominated inflammation had a positive allergy skin test. There was no statistically significant difference in prevalence of positive allergy skin test between eosinophil- and neutrophil-dominated inflammations (p = 0.107). 60.8 per cent of patients with eosinophil-dominated inflammation and 81.8 per cent of patients with neutrophil-dominated inflammation had rhinosinusitis. There was no statistically significant difference in prevalence of rhinosinusitis between eosinophil- and neutrophil-dominated inflammations (p = 0.079). CONCLUSION: Nasal polyps had association with positive allergy skin test (68.5%), rhinosinusitis (67.1%) and eosinophil-dominated inflammation (69.9%). There were no statistically significant differences in prevalence of positive allergy skin test and rhinosinusitis between eosinophil- and neutrophil-dominated inflammations (p = 0.107 and p = 0.079, respectively).

Role of allergy in the therapeutic response of nasal polyps.

The objective of this study was to determine whether the allergy factor affects therapeutic response of nasal polyps. A total of 68 patients were enrolled between 1 October 1999 and 1 January 2002 at the Allergy and Rhinology Clinic, Faculty of Medicine, Songklanagarind Hospital. Allergy skin prick test was performed in order to divide patients into a positive skin test group and a negative skin test group. Their medical history was recorded including age, sex, nasal symptoms, concomitant diseases and medications. Patients in both groups were treated over a 6 week period with Budesonide nasal spray. Nasal symptoms, polyp size, nasal and oral expiratory peak flow were evaluated at each visit. Overall assessment of treatment efficacy was evaluated by patients at 3 and 6 weeks after treatment. The mean value of these variables during treatment and a baseline period were compared within and between groups. After 3 and 6 weeks of treatment of nasal polyps with topical Budesonide nasal spray, nasal symptoms, polyp size, nasal and oral expiratory peak flow index and overall response to treatment were improved within both groups. Comparing the two groups, there were greater improvements in the negative skin test group compared to the positive skin test group in all variables. These differences in variable scores between groups showed a tendency to increase overtime after treatment was terminated. The results demonstrate that nasal polyps with positive allergen skin test had less improvement compared to nasal polyps with negative allergen skin test in all nasal signs and symptoms and these differences in improvement showed a tendency to increase over time after treatment.