A 15yo girl comes into your ED complaining of unilateral facial swelling that started this morning as a little bit of swelling under her R ear, and 8 hours later, is now her entire R cheek. No fevers/chills. ROS otherwise negative.

VS normal. Exam with induration to the R cheek, non tender, no overlying erythema. Mastoid non-tender. Able to speak, swallow, without issue. Pharynx normal.

No sig PMH. Was immunized appropriately.

Whats going on?

Acute unilateral parotitis. Given extent of swelling and involvement of ear, CT scan was done to r/o mastoiditis or underlying abscess and ENT was consulted to see. CT showed a stone and no signs of infection. Started on sialogouges to good effect.

Pearls

Unilateral parotitis is usually associated with duct obstruction, whereas bilateral parotitis more commonly indicates a systemic cause

Acute bacterial parotitis occurs more frequently in elderly patients, neonates (especially preterm infants), and postoperative patients. They will often have high fevers, look toxic, and complain of trismus and dysphagia. Can be dangerous, requires CT scan to exclude abscess and timely IV abx. Its thought to be 2/2 stasis of salivary flow that allows retrograde introduction of bacterial pathogens into the parotid gland, resulting in localized infection. Fungal parotitis can also occur in the elderly.

If there is an abscess, you won’t usually feel fluctuance due to the density of the parotid tissue itself, so you cannot rely on just your exam. In 50% of cases however,  you may be able to express pus.