(817) Empyema Necessitans Secondary to Methicillin-Resistant Staphylococcus aureus: A Case Report

Introduction: Empyema necessitans (EN) is the extension of empyema from the pleural space into the chest wall. It is more common in adult as compare to children. The most common organisms causing EN are Mycobacterium tuberculosis, Actinomyces followed by methicillin-resistant Staphylococcus aureus. Consensus is lacking on management of EN due to the limited literature on this rare complication.

Description: 18 months-old female admitted with fever and cough for one week and respiratory distress for two days. Examination showed swelling and erythema on the left side of the chest wall extending inferiorly from the xiphoid process to the midclavicular line and superiorly up to the subclavicular region with decreased air entry on the left side of the chest. Workup revealed raised septic markers and computed tomography of the chest showed gross left-sided pleural effusion with an enhanced pleural margin, large collection with an enhancing margin in the left lateral chest wall, and smaller fluid collection in the Para mediastinal location consistent with EN. The patient was intubated, and continued on mechanical ventilation for increased work of breathing. Antibiotics ceftriaxone and vancomycin were continued. Left posterolateral thoracotomy and decortication were performed under general anesthesia with more than 500 ml purulent fluid drained and two chest tubes were placed. Cultures revealed MRSA. Pleural fluid for the AFB smear and gene-xpert were negative. An echocardiogram was performed which was negative for vegetation, IV ceftriaxone was discontinued, and vancomycin was switched to intravenous linezolid. Post-procedure radiography showed resolution of the pleural effusion, Chest tubes were removed on 7th postoperative day. The patient was treated with one week of IV antibiotics (4 days of ceftriaxone and vancomycin and 3 days IV linezolid) followed by oral linezolid for 4 weeks. The patient’s hospital course remained uneventful, and Patient was discharged in stable condition on oral antibiotics on postoperative day 9.

Discussion: Any child who presents in the emergency department with respiratory symptoms, chest wall mass, empyema necessitans should be considered as a differential diagnosis. Successful treatment options include surgical drainage with decortication, and a prolonged antibiotic course.