To report an unusual complication of pediatric acute maxillary sinusitis: premaxillary abscess. To describe clinical, radiological and biological presentation, treatment strategy and progression.

A retrospective study included all pediatric patients treated for premaxillary abscess complicating acute maxillary sinusitis in two ENT reference centers between 1999 and 2017. Disease history, clinical presentation, biological and radiological findings, treatment modalities and progression were studied.

Ten patients were included, with a mean age of 10±4.2 years. All presented with fever, rhinorrhea and premaxillary edema. Contrast-enhanced CT scan systematically found complete opacity of the maxillary sinus, without bone lysis, and extensive effusion along the intersinonasal wall up to the premaxillary region, extending in 3 cases back toward the parapharyngeal space. Bacteriology isolated Streptococcus anginosus most frequently (n=4; 40%). Treatment comprised intravenous wide-spectrum antibiotics, with surgical drainage of the abscess if>10mm (n=9; 90%). Seven of these 9 patients (78%) had recurrent abscess requiring surgical revision and 3 (33%) required a third drainage. All patients were cured without sequelae at 1 month.

In case of acute maxillary sinusitis with premaxillary edema, premaxillary abscess should be suspected. The high recurrence rate argues for maximalist surgery associated to close clinical monitoring with radiological examination.