A case of anesthesia mumps in a cat captured with magnetic resonance imaging.

A 6-year-old neutered male domestic shorthair cat was presented because of a 4-week history of upper respiratory noise and suspected upper respiratory tract infection that were unresponsive to antibiotics. On physical examination, the cat had multiple cranial nerve deficits involving cranial nerves III, V, VII, and potentially VIII. Magnetic resonance imaging (MRI) of the head under general anesthesia was conducted. During the MRI, before intravenous contrast administration, the mandibular and parotid salivary glands became acutely symmetrically enlarged. Subsequent cytology of the salivary gland showed no cytological abnormalities. A condition called "anesthesia mumps" has been reported in humans, in which the salivary glands become acutely enlarged during or following general anesthesia. This is a transient swelling, and the underlying cause is unknown; however, several mechanisms have been proposed in the human literature, including physical obstruction of the salivary duct due to patient positioning, administration of anticholinergic drugs, dehydration, and other causes of salivary stasis. A suspected case of anesthesia mumps was reported in a dog following an elective neutering. This is the first reported case of anesthesia mumps in a cat. More importantly, it is the only case in which the acuteness of the swelling was captured with MRI. Key clinical message: A case of acute transient salivary gland swelling secondary to general anesthesia is described. Anesthesiologists and other veterinary professionals should be aware of this rare and benign but potentially alarming anesthesia complication.