Descending necrotizing mediastinitis caused by Streptococcus constellatus: A case report and review of the literature

Rationale: Descending necrotizing mediastinitis (DNM) is a rare but severe mediastinal infection. If not diagnosed and treated promptly, the consequences can be very serious. Here, we shared a successful diagnosis and treatment case of DNM that originates from oral to neck and mediastinum caused by Streptococcus constellatus (S constellatus ). S constellatus is a clinically uncommon gram-positive coccus and is known for its ability to form abscesses. Timely surgical drainage and the correct use of antibiotics are key to successful treatment. Patient concerns: A 53-year-old male admitted to hospital with painful swelling of the right cheek, persistent oral pus and moderate fever lasting 1 week, followed by rapid development of a mediastinal abscess. Diagnoses: He was diagnosed with DNM caused by S constellatus . Interventions: On the evening of admission, an emergency tracheotomy and thoracoscopic exploration and drainage of the right mediastinum, floor of the mouth, parapharynx and neck abscess were performed. Antibiotics were administered immediately. Outcomes: At 28 days post-operatively, the abscess was absorbed, bilateral lung exudate decreased and the patient temperature, aspartate transaminase, alanine transaminase, bilirubin and platelets returned to normal. The patient was discharged after completing 4 weeks of antibiotic therapy. Follow-up at 3 months after discharge revealed no recurrence of the abscess. Lessons: Early surgical drainage and antibiotics treatment are important in mediastinal abscesses and infectious shock due to Streptococcus asteroids.