LAUSR

Laryngeal tuberculosis (TB) is a rare and frequently under-recognised disease. It has no pathognomonic features and can mimic many other disorders. Diagnosis is frequently delayed and can result in significant complications. We report an unusual clinical presentation of laryngeal TB with diagnostic and treatment challenges. A 44-year-old, non-smoker, Filipino female reported a 1-month history of dysphonia associated with a nonproductive cough. She had no haemoptysis, dyspnoea or constitutional symptoms. She had epidermal growth factor receptor (EGFR) mutant lung adenocarcinoma treated with osimertinib as second-line therapy. Her disease was well controlled with known pulmonary, hepatic and skeletal metastases. She was also a chronic hepatitis B carrier on maintenance entecavir with normal liver function and an undetectable viral load. She migrated to Australia more than 15 years ago. She had Bacillus Calmette-Guérin vaccination during childhood and was never treated for TB. Her brother and father-in-law were treated for TB decades prior. Initial laryngoscopic examination identified nonspecific erythema of the vocal cord. Her dysphonia was treated empirically as gastroesophageal reflux but her symptoms persisted despite 1 month of therapy. Repeat laryngoscopy revealed more prominent erythema on the vocal cord and arytenoid portion of the right aryepiglottic fold (Fig. 1A). A computerised tomography scan of the neck demonstrated a submucosal lesion in the right arytenoid (Fig. 1B). Biopsy revealed necrotising granulomatous inflammation with acid-fast bacilli (AFB) organisms seen under light microscopy (Fig. 1C). AFB organisms were also detected in sputum. Mycobacterium tuberculosis complex DNA was detected with polymerase chain reaction. Sensitivity testing showed resistance to isoniazid. She was treated empirically with rifampicin, isoniazid, pyrazinamide and ethambutol as well as moxifloxacin for isoniazid resistance. Her dysphonia improved and a repeat laryngoscopy confirmed resolution of the right arytenoid TB. Laryngeal TB is rare, accounting for less than 1% of TB infections. It typically affects adults in the fifth decade, and can involve any part of the larynx with a spectrum of presentations, including exophytic ‘pseudotumours’, ulcerative, polypoidal and nodular changes. Dysphonia is the most common symptom, involving up to 96% of cases. Given its rarity and non-specific symptoms, it is usually misdiagnosed, resulting in delay in treatment, leading to irreversible damage. To our knowledge, our case is the first reported patient to be diagnosed with laryngeal TB with lung adenocarcinoma. EGFR mutant lung adenocarcinoma is associated with latent TB amongst Asian patients since both diseases are common in this population. Latent TB has a 5–15% lifetime risk of reactivation, particularly in immunocompromised patients. Chemotherapy and