Tonsillitis: Definition and Anatomy

Definition and Anatomy

• Waldeyer's Ring is a ring of lymphoid tissue surrounding the oropharynx, consisting of palatine tonsils, lingual tonsils, nasopharyngeal tonsils (adenoids), and tubal tonsils (lateral pharyngeal bands), which produce B and T lymphocytes.
• The palatine tonsils are located bilaterally in the lateral walls of the oropharynx, with the anterior wall being the palatoglossal fold and the posterior wall being the palatopharyngeal fold.

Etiology and Pathophysiology

• Tonsillitis mainly affects children between 5-10 years old and young adults between 15-25 years old.
• 30-40% of tonsillitis cases are caused by Group A beta-haemolytic Streptococcus, while 60% are caused by other pathogens such as viruses, S. Pyogenes, Staphylococci, Pneumococci, and Haemophilus influenza.
• Most cases start as a viral infection, which then develops into a superimposed bacterial infection.

Clinical Presentation

• Symptoms of tonsillitis include dysphagia, odynophagia, fever (>38.3°C), trismus, halitosis, cervical lymphadenopathy (often tender), and tonsillar enlargement.
• The stages of tonsillitis are erythema, exudative phase, follicular phase (yellow lymphatic spots), and cryptic phase (chronic tonsillitis).

Subtypes

• Superficial/Catarrhal tonsillitis is mostly viral, characterized by a generalized infection of the oropharyngeal mucosa, with follicular spreads into the tonsillar crypts and yellowish exudates.
• Membranous tonsillitis follows the follicular stage, with exudate coalescing to form a membranous sheath on the surface of the tonsils.
• Parenchymatous tonsillitis is characterized by uniform swelling/congestion and erythema.
• Ulcerative tonsillitis is characterized by ulcerations, which can be deep or superficial, and may be indicative of Diptheria or Syphilis (Vincent's angina).

Management

• Investigations for tonsillitis include blood tests (FBC, U&E, CRP), blood cultures (rarely taken), throat smear/pus swab, and rapid immune assay to identify Group A beta-haemolytic Streptomycin.
• Medical management involves antibiotics (7-14 days of oral or intravenous penicillin + B lactamase inhibitors), analgesia, bed rest, fluids, and oral hygiene.
• Surgical management involves tonsillectomy, with indications including suspected tumour, relief of airway obstruction, halitosis, sleep apnoea, and recurrent infections (acute tonsillitis) according to the Paradise score.

Complications

• Local complications include recurrent tonsillitis, chronic tonsillitis, peritonsillar abscess (Quinsy), and spread of infection to the parapharyngeal space and retropharyngeal spaces.

A comprehensive overview of tonsillitis, covering its definition, anatomy, and Waldeyer's Ring, including the role of lymphoid tissue in local defense.