Lund-Mackay System for Computed Tomography Evaluation of Paranasal Sinuses in Patients with Granulomatosis and Polyangiitis.

Granulomatosis with polyangiitis (GPA), a disease capable of affecting any organ, most often acts upon the upper respiratory tract. Diagnostic imaging is primarily represented by computed tomography (CT) of paranasal sinuses. The aim of this study was to define the characteristic changes in paranasal CT in patients with GPA and to evaluate diagnostic usefulness of the Lund-Mackey scoring system (L-M System). The study encompassed 43 patients with GPA of the mean age of 47.7 ± 12.8 years who were treated topically with mupirocin. We found that inflammation occurred mainly in the maxillary sinuses (72%). The mean L-M score was 5.8 ± 6.1. The right maxillary sinus had the highest percentage (12.6%) of score hits of 1, i.e., partial opacification and the left ostiomeatal complex had the highest percentage (7.6%) of score of 2, i.e., complete opacification or obstruction. The following changes were the most characteristic for GPA: sinus mucosal thickening, widespread bone damage, and osteogenesis. We conclude that the long-term topical mupirocin treatment of GPA may inhibit nasal bone damage, but also may led to permanent rhinological changes of the rhinosinusitis type. The Lund-Mackey staging system is a useful diagnostic imaging option in GPA patients.