The 2 most common causes of acute mediastinitis are
Esophageal perforation
Median sternotomy
Esophageal perforation
Esophageal perforation Esophageal Rupture Esophageal rupture may be iatrogenic during endoscopic procedures or other instrumentation or may be spontaneous (Boerhaave syndrome). Patients are seriously ill, with symptoms of mediastinitis... read more may complicate esophagoscopy or insertion of a Sengstaken-Blakemore or Minnesota tube (for esophageal variceal bleeding). Rarely, it results from forceful vomiting (Boerhaave syndrome). Another possible cause is swallowing caustic substances (eg, lye, certain button batteries). Certain pills or esophageal ulcers (eg, in patients with AIDS and esophagitis) can contribute.
Patients with esophageal perforation become acutely ill within hours, with severe chest pain and dyspnea due to mediastinal inflammation.
Diagnosis is usually obvious from clinical presentation and a history of instrumentation or of another risk factor. The diagnosis should also be considered in patients who are very ill, have chest pain, and may have a risk factor that they cannot describe (eg, in patients who are intoxicated and may have vomited forcefully but do not remember and in preverbal children who may have ingested a button battery). The diagnosis is suggested by chest x-ray showing air in the mediastinum and confirmed by CT, although other disorders (eg, spontaneous pneumomediastinum Pneumomediastinum Pneumomediastinum is air in mediastinal interstices. The main causes of pneumomediastinum are Alveolar rupture with dissection of air into the interstitium of the lung with translocation to... read more ) can also cause air in the mediastinum.
Treatment is with parenteral antibiotics selected to be effective against oral and gastrointestinal flora (eg, clindamycin 450 mg IV every 6 hours plus ceftriaxone 2 g IV once a day, for at least 2 weeks). Patients who have severe mediastinitis with pleural effusion Pleural Effusion Pleural effusions are accumulations of fluid within the pleural space. They have multiple causes and are usually classified as transudates or exudates. Detection is by physical examination,... read more or pneumothorax Pneumothorax Pneumothorax is air in the pleural space causing partial or complete lung collapse. Pneumothorax can occur spontaneously or result from trauma or medical procedures. Diagnosis is based on clinical... read more
require emergency surgical exploration of the mediastinum with primary repair of the esophageal tear and drainage of the pleural space and mediastinum.
Median sternotomy
This procedure is complicated by mediastinitis in about 1% of cases (1 Reference Mediastinitis is inflammation of the mediastinum. Acute mediastinitis usually results from esophageal perforation or occurs after median sternotomy. Symptoms include severe chest pain, dyspnea... read more ). Patients most commonly present with wound drainage or sepsis. Diagnosis is based on finding infected fluid obtained by a needle aspiration through the sternum. Treatment consists of immediate surgical drainage, debridement, and parenteral broad-spectrum antibiotics. Mediastinitis after median sternotomy has a high mortality rate.
Chronic fibrosing mediastinitis
This condition usually is due to tuberculosis (TB) Tuberculosis (TB) Tuberculosis is a chronic, progressive mycobacterial infection, often with an asymptomatic latent period following initial infection. Tuberculosis most commonly affects the lungs. Symptoms include... read more or histoplasmosis Histoplasmosis Histoplasmosis is a pulmonary and hematogenous disease caused by Histoplasma capsulatum; it is often chronic and usually follows an asymptomatic primary infection. Symptoms are those... read more
but can be due to sarcoidosis Sarcoidosis Sarcoidosis is an inflammatory disorder resulting in noncaseating granulomas in one or more organs and tissues; etiology is unknown. The lungs and lymphatic system are most often affected, but... read more
or silicosis Silicosis Silicosis is caused by inhalation of respirable crystalline silica dust and is characterized by nodular pulmonary fibrosis. Chronic silicosis generally progresses insidiously and can advance... read more
. Other fungal diseases may also cause chronic fibrosing mediastinitis.
An intense fibrotic process develops, leading to compression of mediastinal structures, which can cause the superior vena cava syndrome Regional spread , tracheal narrowing, or obstruction of the pulmonary arteries or veins.
Diagnosis is based on CT.
If the cause is TB or fungal, antimicrobial therapy is indicated. Otherwise, no known treatment is beneficial, but insertion of vascular or airway stents can be considered.
Reference
1. De Feo M, Renzulli A, Ismeno G, et al. Variables predicting adverse outcome in patients with deep sternal wound infection. Ann Thorac Surg 2001;71(1):324-331. doi:10.1016/s0003-4975(00)02137-8
Drugs Mentioned In This Article
Drug Name | Select Trade |
---|---|
clindamycin |
Cleocin, Cleocin Ovules, Cleocin Pediatric, Cleocin T, CLIN, Clindacin ETZ, Clindacin-P, Clinda-Derm , Clindagel, ClindaMax, ClindaReach, Clindesse, Clindets, Evoclin, PledgaClin, XACIATO |
ceftriaxone |
Ceftrisol Plus, Rocephin |