Causes of Lingual Tonsil Swelling
Lingual tonsil swelling is most commonly caused by viral or bacterial infections, with other potential causes including lymphoid hyperplasia following palatine tonsillectomy, allergic reactions, and rarely, malignancy. 1, 2
Common Infectious Causes
Viral infections account for 70-95% of all tonsillitis cases, including lingual tonsillitis. Common viral pathogens include rhinovirus, coronavirus, adenovirus, influenza virus, parainfluenza virus, respiratory syncytial virus, Epstein-Barr virus, enteroviruses, and herpesviruses 3, 1
Bacterial infections cause approximately 5-15% of tonsillitis in adults and 15-30% in children aged 5-15 years, with Group A beta-hemolytic streptococcus (Streptococcus pyogenes) being the most common bacterial pathogen 3, 4
Other bacterial pathogens that may cause lingual tonsil swelling include Groups C and G beta-hemolytic streptococci, Mycoplasma pneumoniae, and Chlamydia pneumoniae 1
Post-Tonsillectomy Hypertrophy
Lingual tonsillar hypertrophy commonly develops as compensatory lymphoid hyperplasia following palatine tonsillectomy 2, 5
This occurs because the lingual tonsil is part of the Waldeyer's ring of lymphoid tissue and may enlarge to compensate for the removed palatine tonsils 1
Other Causes
Allergic reactions can trigger lingual tonsil swelling as part of a broader inflammatory response 1
Laryngopharyngeal reflux can contribute to lingual tonsillar hypertrophy 1
Obesity has been associated with lingual tonsillar hypertrophy, particularly in children with persistent obstructive sleep apnea after adenotonsillectomy 1
Foreign body embedded in the lingual tonsil can cause recurrent inflammation and abscess formation 2
Rarely, aberrant lingual thyroid tissue may present as a mass at the base of the tongue that can be mistaken for lingual tonsillar hypertrophy 2
Clinical Presentation
Symptoms of lingual tonsillitis may include nocturnal or supine cough, constant throat discomfort, glossal pain, referred otalgia, and dysphagia 2, 5
Unlike palatine tonsils, lingual tonsils lack a capsule, which prevents the formation of a peritonsillar abscess. Instead, infection may spread either into the tongue or into the parapharyngeal space 6
In severe cases, lingual tonsillar hypertrophy can cause airway obstruction, particularly in children with Down syndrome who have a higher prevalence of lingual tonsillar hypertrophy 1
Diagnostic Considerations
Lingual tonsil swelling may be difficult to visualize during routine oropharyngeal examination and may require laryngeal mirror examination, flexible laryngoscopy, or imaging studies 2, 1
Diagnostic techniques to identify lingual tonsillar hypertrophy include awake flexible laryngoscopy, drug-induced sleep endoscopy (DISE), plain neck X-rays, computed tomography, or MRI studies 1
Clinical Implications
Lingual tonsillar hypertrophy is a common cause of persistent obstructive sleep apnea in children who have undergone adenotonsillectomy, occurring in up to 85% of affected children 1
Lingual tonsil abscess, although rare, represents an important potential cause of airway obstruction and should be considered in patients with sore throat and normal oropharyngeal examination 6