Editorial: Inflammatory and allergic diseases of the upper airways

T his issue of American Journal of Rhinology and Allergy (AJRA) covers a diverse selection of articles on basic and clinical aspects of inflamma-tory diseases of the upper airways. One such disease , chronic rhinosinusitis (CRS), significantly lowers quality of life. Despite recent progress, however, CRS remains poorly understood. A few of the articles in this AJRA issue focus on the pathophysiology of CRS. The literature indicates a role for prostaglan-din-E2 and E-prostanoid (EP) receptors in CRS. When comparing EP receptors in CRS subtypes, Xie et al. 1 found enhanced EP1 receptor messenger RNA (mRNA) and protein expression in eosinophilic CRS with nasal polyps (CRSwNP). However, EP4 mRNA levels were higher than EP1, EP2, and EP3 levels in controls; in CRS without nasal polyps (CRSsNP); and in noneosinophilic CRSwNP. 1 Nasal tissue eosinophilia is a hallmark of CRSwNP, especially in patients from Western countries. Results of studies have shown an association between tissue eosinophilia and polyp recurrence. In their retrospective analysis from China of 387 patients with CRSwNP, Lou et al. 2 found a significant correlation between tissue eosinophilia and polyp recurrence. They showed that tissue eosinophils Ͼ27% of total cells or a tissue eosinophil absolute count of Ն55 eosinophils per high power field is a reliable prognostic indicator for nasal polyp recurrence within 2 years after surgery. 2 CRS has been linked to imbalances in the production of eicosanoids (arachidonic acid metabolites), which results from phospholipid hydrolysis by phospholipase A2 (PLA2). Mruwat et al. 3 investigated the expression of PLA2s and multiple cytokines in super-antigen Staphylococcus aureus enterotoxin stimulated human nasal polyps from patients with CRSwNP. Stimulation of nasal polyp cells by S. aureus enterotoxin induced cytokine secretion and enhanced expression of several secretory PLA2 and calcium-independent PLA2, while suppressing cytoplasmic PLA2 expression. This supports a role for secretory PLA2s in the pathophysiology of CRS. 3 Wang et al. 4 evaluated the ethmoid bone tissue samples from a group of patients with CRS by histologic examination and quantitative real-time reverse transcription polymerase chain reaction and showed an increased infiltration of eosinophils in the periosteum, along with neo-osteogenesis in CRS. The investigators found increased expression of TGF-␤1, TGF-␤ receptor I, and p-Smad3 in patients with CRSwNP compared with CRSsNP at the mRNA and protein levels. The investigators concluded that these findings were indicative of a potential role for eosinophils in the bone remodeling process in CRSwNP. 4 Oral steroids are …