Common clinical symptoms of Hunter syndrome that ENT specialists will encounter include: frequent hearing loss (due to otitis media or other conductive impairment or sensorineural degeneration); breathing and chewing/swallowing difficulties and obstructive sleep apnoea due to respiratory obstructions (enlarged tonsils and adenoids, nasal obstructions); skeletal deformities; and abdominal distension.^1,2

Otological and audiological evaluations performed every 6–12 months can be used to monitor hearing loss, while a diagnosis of the airway obstructions requires a comprehensive evaluation of the medical history of the patient, a current physical examination and imaging procedures. Pulmonary function can be tested using spirometry, and an overnight sleep study, conducted at a hospital or at home, can be used to evaluate the severity of obstructive sleep apnoea. For a more detailed assessment, a bronchoscopy can be used to evaluate respiratory involvement with a rigid bronchoscope and a flexible bronchoscope.^1,2

Managing airway problems in Hunter syndrome patients often involves surgery, but preparation is crucial: patients should be assessed by a multidisciplinary team that includes a cardiologist, an ENT specialist and an anaesthetist with experience in MPS diseases before any surgical procedure. However, due to the progressive nature of airway involvement, surgery may only provide a temporary solution and continual monitoring is important.²