IgG4 Positivity in Chronic Tonsillitis: A New Component of IgG4-Related Disease?

Objective: Immunoglobulin G4-related disease (IgG4-RD) and chronic tonsillitis are both chronic fibroinflammatory diseases in which tissue atrophy is sometimes observed. In this study, the authors aimed to investigate the pathologic IgG4 positivity in tonsillectomy specimens and hypothesized to name it as a new clinical component of IgG4-RD if there is significant IgG4 positivity in chronic tonsillitis. Methods: A total of 73 patients who underwent tonsillectomy for chronic tonsillitis were included in this study. Of these, 31 patients had atrophic form chronic tonsillitis. Pathologic examinations and specific IgG4 immunohistochemical staining were performed by the same experienced pathologist in terms of IgG4-RD. Results: Sixty-three percent (n=46) of the cases were male, 37% (n=27) were female, their ages ranged from 3 to 51, and the mean age was 19.11 +/- 14.82. It was determined that 23.3% (n=17) of the cases participating in the study were IgG4-positive. When the pathologic grades of the cases were examined; it was observed that 13.7% (n=10) were Grade I, 65.8% (n=48) were Grade II, and 20.5% (n=15) were Grade III. A statistically significant difference was found between the pathology degrees of the cases according to the IgG4 groups (P=0.001; P<0.01). Conclusion: The authors concluded that as the histopathologic grades of chronic lymphoplasmacytic inflammation in tonsils specimen increase, IgG4 positivity rates also increase. Therefore, this clinical entity may be a new IgG4-related disease state in cases with chronic tonsillitis. Level of Evidence: Level II.