Correlation between the Prostaglandin D2/E2 Ratio in Nasal Polyps and the Recalcitrant Pathophysiology of Chronic Rhinosinusitis Associated with Bronchial Asthma

BACKGROUND: The prevalence of patients with chronic rhinosinusitis (CRS) refractory to traditional therapy appears to be on the increase. In these cases, CRS tends to be associated with bronchial asthma (BA), especially, aspirin-intolerant asthma (AIA). On the other hand, arachidonic acid metabolites have been extensively investigated in the pathogenesis of BA. We sought to assess the role of prostaglandin D(2) (PGD(2)) and prostaglandin E(2) (PGE(2)) in the recalcitrant pathophysiology of CRS. METHODS: Samples were prepared from the nasal polyps and mucosa of 40 patients undergoing endoscopic sinus surgery (ESS) at our hospital. The nasal polyp specimens obtained from the patients with CRS were divided into three groups, as follows: the CRS-AIA group, consisting of specimens obtained from patients with CRS complicated by AIA, the CRS-ATA group, consisting of specimens obtained from patients with CRS associated with aspirin-tolerant asthma (ATA), and the CRS-NA group, consisting of specimens obtained from CRS patients without BA. PGD(2) and PGE(2) were extracted from the specimens and quantified. RESULTS: The concentrations of PGD(2) were significantly higher in the nasal polyps of the CRS-ATA group. The concentrations of PGE(2) were lowest in the nasal polyps of the CRS-AIA group. The PGD(2)/PGE(2) ratio was highest in the CRS-AIA group. CONCLUSIONS: It has previously been reported that CRS complicated by AIA is most likely to be characterized by repeated remissions and relapses, and is thus the most intractable. We may therefore say that the PGD(2)/PGE(2) ratio reflects the intractable nature of CRS.