Causes of Unilateral Parotitis and Mastoiditis

Underlying Mechanism

Parotitis typically results from decreased salivary flow or ductal obstruction, leading to ascending infection from the oral cavity 1

The American Academy of Pediatrics notes that Streptococcus pneumoniae remains the most common pathogen (28.57% of culture-positive cases) in acute mastoiditis 2
The American Academy of Pediatrics also notes that Streptococcus pyogenes causes more severe inflammation and higher rates of spontaneous tympanic membrane rupture and progression to acute mastoiditis 2
The Centers for Disease Control and Prevention indicates that Haemophilus influenzae has become nearly equal in frequency to S. pneumoniae following PCV7 vaccination 2
Prior antibiotic treatment does not prevent mastoiditis development, with 33-81% of patients having received antibiotics before diagnosis, according to clinical guidelines 3