(617) Mediastinitis, Empyema, and Chest Wall Infiltration From the Retropharyngeal Abscess: A Rare Event

Introduction: Mediastinal abscesses are rare in children. We report a retropharyngeal abscess that progressed into a mediastinal abscess and empyema and extended into the subcutaneous fascia of the neck and chest wall in a previously healthy infant.

Description: A 9-month-old female presented with fever, URI symptoms, and subsequently upper airway obstruction with stridor, and noisy breathing, on day of admission (DOA) 2. A CT scan of the neck and chest with contrast showed retropharyngeal phlegmon extending from the hypopharynx to prevertebral space and posterior mediastinum. The patient required emergent airway protection by endotracheal intubation and an incision in the pharynx to drain the retropharyngeal phlegmon. As CT scan did not show an obvious drainable collection, intervention into the mediastinum was deferred. Vancomycin, clindamycin, and ceftriaxone were initiated, and the patient was continued on ventilatory support. A moderate-sized left-side pleural effusion was noted on chest ultrasound on DOA 4. An 8.5 Fr Pigtail catheter was placed in the left pleural space, and purulent pleural fluid was drained. On DOA 6, her left arm and chest wall were edematous and swollen. Repeat CT scan of the chest showed progression of retropharyngeal and neck abscesses, mediastinal abscess, empyema, and a possible connection into the subcutaneous space of the chest and left arm also connecting with defects in the pleural and mediastinal cavities. Exploration of retropharyngeal abscess and video-assisted thoracoscopic surgery requiring total lung decortication was performed. Exploration of the pleural apex identified a medial defect tracking into the mediastinum and a 19 Fr JP drain was placed within this mediastinal cavity. A 20 Fr chest tube was placed into the pleural cavity and the previous pigtail catheter was removed. The deep subcutaneous communicating abscess in the neck was drained with a Penrose drain. Methicillin-resistant Staphylococcus aureus was isolated from the retropharyngeal collection, pleural fluid, and neck abscess. Our patient received six weeks of intravenous antibiotics and two weeks of oral antibiotics.

Discussion: Mediastinal abscesses communicating into the pleural cavity and subcutaneous tissue of the neck and chest wall are extremely rare and demonstrate the virulence of MRSA.