Tonsillar Actinomycosis as a Cause of Asymmetric Tonsil Hypertrophy

Background: Actinomyces are organisms in the oropharynx that can colonize tonsillar tissue. This study aimed to determine the prevalence of tonsillar actinomycosis in patients with asymmetric tonsil enlargement and identify associated clinical factors.
Methods: This retrospective cohort study included 132 adult patients who underwent tonsillectomy for asymmetric tonsil enlargement between 2019 and 2024. Clinical data including age, sex, and tonsil grade were collected. All specimens underwent histopathological examination with hematoxylin and eosin staining to identify Actinomyces colonization.
Results: Actinomyces colonization was identified in 18 of 132 patients (13.64%). The mean age of Actinomyces-positive patients was significantly higher than Actinomyces-negative patients (58.78 ± 19.43 vs. 41.05 ± 18.47 years, p=0.0009). Age-stratified analysis showed progressive increase in prevalence with age, reaching 34.38% in patients ≥61 years. No significant sex difference was observed (p=0.447). Higher tonsil grades were strongly associated with Actinomyces colonization, with Grade 4 tonsils showing prevalence rates of 31.25% (right) and 37.50% (left).
Conclusions: Tonsillar actinomycosis should be considered in the differential diagnosis of asymmetric tonsil hypertrophy, particularly in older patients with higher grade enlargement. Histopathological examination remains essential for accurate diagnosis and appropriate management.