Introduction: Acute suppurative parotitis (ASP) is a rare condition in early infancy. It usually presents unilaterally, with inflammatory signs in the parotid region and non-specific systemic symptoms. Staphylococcus aureus (S. aureus) is the most common causative agent of ASP, and male sex, prematurity, low birth weight, dehydration, parotid duct obstruction and immunosuppression are risk factors. Most reported cases occur in the neonatal period, and they can be complicated by abscesses and sepsis. 

Description of case: We present a case of a 57-day-old girl with a history of left submandibular tumefaction, fever, and irritability. Parotid ultrasonography revealed findings compatible with bilateral parotitis and associated phlegmon. Empirical treatment with flucloxacillin was initiated. On the sixth day, the worsening of inflammatory signs on the left side and the onset of inflammatory signs on the right side occurred, and ultrasonography revealed areas of necrotic content bilaterally. Ultrasound-guided drainage of the abscess collections isolated flucloxacillin-sensitive, penicillin-resistant S. aureus from the pus culture. Antibiotic treatment was adjusted, and the patient completed 7 days of flucloxacillin and 4 days of gentamicin treatment, with regression of the swelling and complete resolution. No risk factors for ASP were identified. An immunological study was performed, the results of which were normal. During follow-up, no recurrence or complications were reported. 

Conclusions: Although ASP is less frequent now than in the past, we must be aware of potentially fatal complications if adequate treatment is not initiated early. Unlike most reported cases, the present case involved an exuberant, bilateral presentation in a girl after the neonatal period, without relevant risk factors, complicated despite the initiation of antibiotic therapy. This case required the exclusion of immunodeficiency, as otolaryngological presentations are a common manifestation of immunodeficiencies.