Impact of baseline clinical and radiological features on outcome of chronic rhinosinusitis in granulomatosis with polyangiitis

Abstract

Background: Granulomatosis with polyangiitis (GPA) causes a recurring inflammation in nose and paranasal sinuses that clinically resembles chronic rhinosinusitis (CRS) of other aetiologies. While sinonasal inflammation is not among the life-threatening features of GPA, patients report it to have major negative impact on quality of life. A relatively large proportion of GPA patients have severe CRS with extensive damage to nose and sinus structures evident by CT, but risk factors for severe CRS development remain largely unknown. In this study, we aimed to identify clinical and radiological predictors of CRS-related damage in GPA.

Methods: We included GPA patients who had clinical data sets from time of diagnosis, and two or more paranasal sinus CT scans obtained ≥12 months apart available for analysis. We defined time from first to last CT as the study observation period, and evaluated CRS development across this period using CT scores for inflammatory sinus bone thickening (osteitis), bone destructions, and sinus opacifications (here defined as mucosal disease). In logistic regression, we applied osteitis as main outcome measure for CRS-related damage.

Results: We evaluated 697 CT scans obtained over median 5 years observation from 116 GPA patients. We found that 39% (45/116) of the GPA patients remained free from CRS damage across the study observation period, while 33% (38/116) had progressive damage. By end of observation, 32% (37/116) of the GPA patients had developed severe osteitis. We identified mucosal disease at baseline as a predictor for osteitis (odds ratio 1.33), and we found that renal involvement at baseline was less common in patients with severe osteitis at last CT (41%, 15/37) than in patients with no osteitis (60%, 27/45).

Conclusions: In this largely unselected GPA patient cohort, baseline sinus mucosal disease associated with CRS-related damage, as measured by osteitis at the end of follow-up. We found no significant association with clinical factors, but the data set indicated an inverse relationship between renal involvement and severe sinonasal affliction.

Keywords: Chronic rhinosinusitis; Granulomatosis with polyangiitis; Inflammation; Osteitis; Paranasal sinuses; Saddle nose deformity.

Fig. 1

Plot showing the study timeline and osteitis development from baseline to end of follow-up. a Timeline plot. Timepoint zero was defined as the year of diagnosis. Median differences between the year of diagnosis and the time of the baseline and the last CT are shown as diamond-shaped points, and the interquartile ranges are shown as horizontal error bars. The mean study observation period with error bars of 2 standard deviations is shown at the bottom. b Groups of the study. At baseline, there were two groups. Three different osteitis trajectories ended in three different outcome groups. The connection lines show how the patients changed groups during the study observation period

Fig. 2

The levels of the three CT parameters at baseline and last CT. Upper panel shows bone thickening (i.e. osteitis) measured by Global Osteitis Scoring Scale (GOSS), number of destructed sinonasal bone structures in the middle panel, and sinonasal mucosal disease measured by the Lund-Mackay score (LM-score) in the bottom panel. The variables are grouped by the degree of osteitis severity at last CT. The observations are shown as red dots

Fig. 3

Associations to the degree of osteitis severity at last CT. Demographic data including age at diagnosis (a), baseline clinical data (b), and total sinus surgery (c). Limited/severe disease is by the definition of the WGET research group