Necrotizing descending mediastinitis by Acinetobacter Baumannii in an out-patient: a case report

Abstract

Background Complicated cervico-facial cellulitis is an infectious disease which can have fatal prognosis. Necrotizing descending mediastinitis is a rare and fatal complication of cervico-thoracic cellulitis. This is the case of necrotizing descending mediastinitis complicating by a multi-resistant Acinetobacter Baumannii in a 27-year-old female, with early management of hemodynamic, respiratory and surgical emergencies, and very careful post-operative care, resulting in very satisfying outcome. Case presentation The patient presented was first treated with broad spectrum antibiotics for Ludwig’s angina for 10 days, then presented with a swelling of sub-mandibular, sub-mental, and cervical regions, a mild respiratory distress, with clinical enhancement of dyspnea in proclive position, tachycardia of 100 beats per minute, and arterial blood pressure of 10/5. Clinical exam showed a tight trismus, with oral opening inferior to 1 cm, no inflammatory signs in facial and cervical swollen areas, and a saturation of 95% in proclive position. Auscultation suspected a pericardial effusion. CT scan with and without injected contrast medium showed diffuse abscesses of sub-mental, sub-mandibular, retro-pharyngeal, para-pharyngeal regions, along with mediastinal abscesses and pericardial effusion. Trans-thoracic ultrasound showed 2 cm pericardial effusion, preserved function of myocardium, and without signs of tamponade. The diagnosis of necrotizing descending mediastinitis with pericardial effusion was established. The patient underwent a course of wide spectrum antibiotic therapy, low doses of cathecholamine, and a surgical drainage through cervical approach of all implicated zones. The surgical dissection was thorough and difficult due to diffuse fibrosis found in tissues of cervical regions. Two hundred milliliters of pus was evacuated, with a placement of surgical drains and Delbet blades. Bacteriological exam found an Acinetobacter Baumannii sensitive to colistin only. The post-operative outcome showed clinical and biological enhancement; however, a residual mediastinal collection appeared in control CT scan after 48 h, which indicated a surgical revision through mediastinoscopy. The post-operative outcome was satisfying with stabilized clinical, biological, and radiological aspects. Conclusions Necrotizing descending mediastinitis is an infectious disease correlated with a very elevated mortality rate, and management is based on airway control, antibiotic therapy, and surgical treatment, as well as the post-operative intensive unit care. Early diagnosis and appropriate management enhances outcome and decreases mortality significantly.