Histologic findings in humans and dogs are somewhat similar but the distribution of affected glands and clinical course are very different. In humans, NS is a benign self-limiting ischemic disorder of the salivary glands which has histologic features that have caused confusion with neoplasia. The characteristic histologic findings are ischemic necrosis of salivary lobules and secondary squamous metaplasia of salivary ducts. The palatine glands are most commonly affected. NS affects the submandibular salivary gland and has much more severe clinical signs.
Affected dogs appear to be in extreme pain and vomit frequently.
Sialoadenectomy of affected glands results in little if any improvement, while sialoadenectomy followed by short-term administration of an anticonvulsant appears to be an effective treatment. The Department of Otolaryngic Pathology reviewed this case. They do not consider the histologic findings consistent with necrotizing sialometaplasia because there is no true replacement of acinar tissue by well developed squamous metaplasia. Necrotizing sialometaplasia of the larynx. Rapidly growing mass noticed on the scapular region for the last 40 days.