Primary laryngeal amyloidosis is a rare benign disease of unknown aetiology. It can present with dysphonia or stridor. A woman presenting with airway compromise, who required a tracheostomy, is reported.
- laryngeal disease
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A 47 year old woman presented with a seven year history of dysphonia which had deteriorated recently. Fibre optic laryngoscopy showed polyps on the right false vocal cord with a suggestion of subglottic stenosis (fig 1). The true vocal cords were mobile and appeared normal.
While awaiting further investigation, she presented with airway compromise requiring urgent tracheostomy. Direct laryngoscopy revealed subglottic oedema. The polypoid lesion was biopsied and showed features suggestive of amyloidosis and this was confirmed after staining with Congo red. A flexible bronchoscopy through the tracheostomy tube showed isolated nodules within the trachea (fig 2). Full blood count and erythrocyte sedimentation rates were normal.
Amyloidosis is a rare benign disease of unknown aetiology.
Laryngeal amyloidosis can present with hoarseness or stridor which may require tracheostomy.
Histological diagnosis from a biopsy specimen can be confirmed with characteristic staining with Congo red.
Treatment is by surgical resection using the carbon dioxide laser. Repeated resections may be necessary.
At follow up a year later she was noted to have a change in voice. Fibre optic laryngoscopy showed new lesions on the right and left true vocal cords. These were resected with a carbon dioxide laser. The result was a subjective improvement in the quality of her voice and airway. She was decannulated two months later. She remains under review and requires no further intervention.
Amyloidosis is a benign, slowly progressive condition that is characterised by extracellular fibular proteins. Diagnosis is confirmed by histopathological specimens that stain with Congo red.1Amyloidosis can be classified as either primary, developing spontaneously, or secondary to some other longstanding inflammatory disease such as rheumatoid arthritis.2 3 The primary form can be further subdivided into a localised form, where deposits are confined to a single organ or location, or generalised, where deposits are found to some extent in all tissues.
The most common presenting symptoms of primary laryngeal amyloidosis are dysphonia and stridor. Rarely, airway compromise occurs and an alternative airway may be necessary. The presence of tender bones, lymphadenopathy, or splenomegaly should alert the clinician to the possibility of generalised amyloidosis.2 Microlaryngoscopy reveals pinkish grey masses lying under the intact epithelium, either as nodular masses or subepithelial deposits. Localisation of lesions in the larynx is to the ventricle, false vocal cords, true vocal cords, aryepiglottic folds, and subglottis in that order of frequency.2 4 Histology of the biopsied specimen using routine haematoxylin and eosin stain shows amyloid as eosinophilic extracellular infiltrate. Further staining with Congo red reveals characteristic apple green birefringence with a polarising microscope confirming the diagnosis.
Treatment of localised laryngeal amyloid deposits is by surgical removal.5 Several authors have reported good results using the carbon dioxide laser.6-9 This disease is slowly progressive and repeated removal may be required.10 The carbon dioxide laser has been shown to be more effective than conventional surgery because it minimises trauma.9 Regular follow up is important as its recurrent nature may require repeated resections using the carbon dioxide laser.