Vocal fold granulomas in six brachycephalic dogs: clinical, macroscopical and histological features

Abstract

Vocal cord granulomas are rarely observed in brachycephalic breeds but often reported in humans as contact granulomas. Six French bulldogs were included in this retrospective descriptive study. Endoscopic laryngeal examinations were performed on all dogs under general anaesthesia. Vocal cord lesions were exclusively unilateral, exophytic, approximately 3-mm wide ulcerated mucosal nodules, arising from the vocal cord. Histopathological examination mainly revealed chronic inflammatory changes on the laryngeal epithelium which were consistent with laryngeal granulomas described in humans, except for the location: vocal cord in dogs versus vocal process in humans. In humans, granulomas result from chronic physical or chemical insult to laryngeal mucosa (chronic cough or throat clearing, vocal abuse, gastro-esophageal reflux). In brachycephalic breeds, chronic inspiratory efforts and air turbulences and gastro-esophageal reflux are suspected to result in chronic laryngeal inflammation.

Infiltrative laryngeal disease in dogs

“…The formation of granulation tissue with inflammatory infiltrate on histopathology has been suggested to occur in brachycephalic dogs as a sequelae to repetitive micro-trauma secondary to airway collapse and negative upper airway pressures in a study of French bulldogs (Sarran et al 2018). French bulldogs have a high prevalence of regurgitation and vomiting (Kaye et al 2018) and it was suggested that gastro-oesophageal reflux could be a contributing factor as in humans, although this has not specifically investigated in dogs.…”

“…Neoplasms involving the larynx in dogs have been described infrequently and include squamous cell carcinoma (Nazifi et al 2006), extramedullary plasmacytoma (Witham et al 2012), mast cell tumour (Beaumont et al 1979), rhabdomyosarcoma (Sanspoux 2016), chondrosarcoma (Shoieb 2014), melanoma and myxochondroma (Ramírez et al 2015). In contrast, non-neoplastic lesions are poorly characterised with inflammatory laryngeal diseases mentioned in a textbook (MacPhail 2017) and reports on granulomas (granulation tissue) associated with chronic intubation (Neilson & Pinelas 2016), brachycephalic obstructive airway syndrome (Sarran et al 2018) and secondary to Leishmania (Torrent et al 2018).…”

Pathology in Practice

“…Brachycephalic breeds of other species may also be presented with lesions that are inferred to be related to reduced laryngeal diameter as a result of brachycephaly; for example, exophytic, ulcerated granulomatous lesions have been noted in the vocal folds of 6 French Bulldogs. 21 Another interesting facet of the clinical presentation of laryngeal chondritis in Texel sheep is that in some cases it is accompanied by diaphragmatic pathology, such as hemorrhage or hematoma, dia-phragmatic myonecrosis, or overt rupture, with or without attendant thoracic hemorrhage. 4,22 It is possible that this represents an epiphenomenon, with laryngeal pathology and consequent dyspnea leading to increased intrathoracic pressure and ensuing diaphragmatic lesions and hemorrhage.…”