FRI0462 Nasal Mucosa Narrow Band Imaging (NBI) in Granulomatosis with Poliangiitis (Wegener Granulomatosis): A Preliminary Study

Abstract

Background Granulomatosis with polyangiitis, former Wegener's (GPA) is a systemic vasculitis characterized by necrotizing granulomatous inflammation and necrotizing vasculitis classically affecting the ear, nose and throat (ENT) district, the lower respiratory tract, and kidneys [1]. Otorhinolaryngological symptoms can be the first localized expression of the disease in a vast majority of patients (73-93%) [2]. NBI endoscopy allows for real-time visualization of mucosal and submucosal vascular patterns and it is used to distinguish precancerous and cancerous lesions of the head and neck [3]. Objectives To investigate the role of NBI in GPA and to evaluated whether disease-specific mucosal vascular pattern alterations could be present. Methods Endoscopic evaluation of upper airways with NBI was performed in 4 groups of patients: 1) 14 patients already diagnosed with GPA; 2) 9 patients with signs and symptoms of EGPA who needed to undergo nasal biopsy to confirm their diagnosis 3) 21 patients affected by chronic rhinosinusits with nasal polyps 4) 25 healthy controls. The presence of NBI vascular alterations and histological results in patients in group 1 and 2 were matched with the final diagnosis in a cross tabulation. Sensibility (SE), specificity (SP), positive predictive value (PPV) and negative predictive value (NPV) were calculated. Results 11 areas with vascular abnormalities were identified in nasal and sinonasal mucosa of 10 patients (8 pts in group 1 and 2 pts in group 2). The anomalous patterns differed substantially from one patient to another. Patients in group 3 and group 4 showed a normal pattern. SE, SP, PPV and NPV of NBI compared with final diagnosis of GPA in group 2 were 0.40, 1, 1 and 0.57 respectively. SE, SP, PPV and NPV of histology compared with final diagnosis of GPA in group 2 were 0.60, 1, 1 and 0.67 respectively. SE, SP, PPV and NPV of NBI compared with final diagnosis of GPA in group 1 + group 2 were 0.53, 1, 1 and 0.31 respectively. SE, SP, PPV and NPV of histology compared with final diagnosis of GPA in group 1 + group 2 were 0.43, 1, 1 and 0.33 respectively. Conclusions Compared to nasal biopsy, NBI endoscopy is a less invasive and time-demanding technique. In our cohort of patients NBI nasal endoscopy offered diagnostic sensitivity and specificity similar to histology. This novel technique, combined with other tests, could help clinicians to reach sufficient diagnostic evidence of GPA and could be used to direct tissue sampling. We consider NBI a promising rapid technique that, on the basis of future studies, could become a supplementary diagnostic tool in the complex workup of GPA. References Hoffman GS, Kerr GS, Leavitt RY et al. Wegener granulomatosis: an analysis of 158 patients. Ann Intern Med 1992;116:488-98. Srouji IA, Andrews P, Edwards C, Lund VJ. Patterns of presentation and diagnosis of patients with Wegener's granulomatosis: ENT aspects. J Laryngol Otol. 2007;121:653-8. Watanabe A, Taniguchi M, Tsujie H, Hosokawa M, Fujita M, Sasaki S. The value of narr...