Clinical Presentation
A chronic and slowly progressive airway compression is the usual presentation of RG, and this can last many years in areas where iodine deficiency is endemic23. A choking sensation exacerbated by the supine position, globus, wheezing, and exercise-induced dyspnea (both mistaken for asthma), or dysphagia are the symptoms most commonly reported by patients, that on the other hand are asymptomatic at presentation in over one-third of cases5. Mechanisms of dyspnea are believed to be direct extrinsic tracheal compression, dysfunction of the recurrent laryngeal nerve, and lung atelectasis24. Instead, in less than 5 % of cases the clinical presentation of RG may be acute: spontaneous hemorrhagic enlargement of RG may occur during pregnancy25,26 or for unclear reasons27,28, acute asphyxia and cardiac arrest have been described29,30, and some authors have hypothesized a direct phrenic nerve compression by the RG as the main cause of these dramatic scenarios31.
Rarer presentation may be constituted by thyrotoxicosis or symptoms of superior vena cava syndrome (facial plethora and congestion, upper neck cyanosis, or a positive Pemberton’s sign with facial flushing and engorgement of superficial jugular veins upon raising the arms)5. While it had been previously reported that this syndrome was more often associated with malignancy, this remains unproven21. Isolated dysphagia is also possible in case of goiter growing only in the retro-esophageal plane32,33, while the only presenting symptom may also be represented by oropharyngeal bleeding because of pharyngolaryngeal “downhill” (i.e ., without venous portal hypertension) varices34. Furthermore lower and upper extremities edema35, pericardial effusion, chylothorax, or hemoptysis because of tracheal varices have been also described21.