Mediastinitis describes an inflammation of the mediastinum and can occur after an injury or the spread of an infection from adjacent structures in the head and neck. It is a medical emergency that requires immediate treatment.
Presentation
Patients with mediastinitis usually report a recent upper respiratory tract infection, surgery in the thorax, infection of the teeth, pain with swallowing, altered mental status, dyspnea, sore throat and shortness of breath [8].
Symptoms of mediastinitis usually start a few days before the patient presents to the emergency department. Nonetheless, in selective cases, the symptoms may appear suddenly and last only a few hours.
History is very important in establishing a diagnosis for the condition. Relevant history includes a recent bronchoscopy, endoscopy, cancer in the thorax or ingestion of a chicken or a fish bone.
Sudden development of mediastinitis may indicate a history of drug abuse in patients who cannot recall that they have vomited forcefully or among children who possibly ingested a harmful substance.
Chronic diseases such as diabetes, autoimmune diseases and chemotherapy may also predispose for mediastinitis. In addition, patients with a history of drug abuse are at an increased risk.
Immune System
- Mediastinal Lymphadenopathy
In addition to right lung infiltrates, she developed mediastinal lymphadenopathy. After transbronchial biopsy confirmation of histoplasmosis, she received therapy with oral itraconazole. [ahajournals.org]
A 74-year-old woman was monitored in Pulmonology Clinic for presenting mediastinal lymphadenopathy ( Fig. 1 D). EUS-FNA (Cook needle, 22-gauge) was performed with a total of 4 passes (subcarinal adenopathy, 7), with no immediate complications. [elsevier.pt]
A 74-year-old woman was monitored in Pulmonology Clinic for presenting mediastinal lymphadenopathy (Fig. 1D). EUS-FNA (Cook needle, 22-gauge) was performed with a total of 4 passes (subcarinal adenopathy, 7), with no immediate complications. [journalpulmonology.org]
CT also may depict associated abnormalities, such as pleural and pericardial effusions, vein thrombosis, and lymphadenopathy. [radiologykey.com]
Computed tomography scan of the chest showed stippled-type calcified mediastinal lymphadenopathy of 1.6 cm x 2.1 cm, and right hilar mass of 3.8 x 4.8 cm (Figure 2). [cureus.com]
Entire Body System
- Asymptomatic
In a majority of patients, the infection with Histoplasma capsulatum is subclinical and starts as an asymptomatic infection of the lungs that disseminates to the lymphatic nodes in the mediastinum. [news-medical.net]
Most patients can be asymptomatic. Pulmonary infiltrates with mediastinal lymphadenopathy should raise the suspicion for histoplasmosis. [ahajournals.org]
Exact epidemiological information is difficult to assess, as majority of patients infected with H. capsulatum are asymptomatic. Outside the US, most cases are unreported, however case series have been reported in the United Kingdom [5]. [clinmedjournals.org]
Diagnosis is challenging since patients are commonly asymptomatic initially or may present with very few signs and symptoms. It is usually established with imaging modalities such as MRI. [symptoma.com]
Although most adults in endemic areas have evidence of prior infection based on skin testing to histoplasmin (1, 2), infection is asymptomatic or produces mild respiratory symptoms only in most patients with an intact immune system (3). [atsjournals.org]
- Lymphadenopathy
It is essential to follow scrupulously the recommendations of the regulations to avoid contamination of the endoscope's channel and its subsequent spread to lymphadenopathy through the needle puncture. [elsevier.pt]
In addition to right lung infiltrates, she developed mediastinal lymphadenopathy. After transbronchial biopsy confirmation of histoplasmosis, she received therapy with oral itraconazole. [ahajournals.org]
CT found a venous infarct in the right lung in addition to extensive lymphadenopathy in the mediastinum and pulmonary hila, with associated calcifications almost completely occluding the superior vena cava and azygos vein. [ncbi.nlm.nih.gov]
CT Features may include: evidence of mediastinal inflammation such as fat stranding, edema and loss of the normal fat planes single or multiple mediastinal fluid collections which may contain gas locules and demonstrate an enhancing wall locoregional lymphadenopathy [radiopaedia.org]
- Malaise
The possibility of mediastinitis should always be kept in mind when a patient complains of fever over a long period of time as well as chest pain and malaise after an EBUS-TBNA or EUS-FNA procedure. [ncbi.nlm.nih.gov]
After 48 h, she started feeling general malaise, retrosternal pain radiating to the neck, odynophagia, dysphagia, fever, and erythematous, and pruriginous maculo-papular lesions in the trunk and upper limbs. [elsevier.pt]
After 48h, she started feeling general malaise, retrosternal pain radiating to the neck, odynophagia, dysphagia, fever, and erythematous, and pruriginous maculo-papular lesions in the trunk and upper limbs. [journalpulmonology.org]
Clinically, patients presented with a biphasic illness characterized by an initial insidious flu-like illness lasting 2 to 4 days and characterized by fever, malaise, myalgias, and nonproductive cough. [radiologykey.com]
- Fatigue
If patients are symptomatic, the most common complaints are fever, sore throat, fatigue, and enlarged lymph nodes. [jcm.asm.org]
The patient has been feeling more fatigued and tired for last few months. On admission, vitals were normal. On physical examination, he was anxious and appeared to be in distress, rest of the systemic examination was unremarkable. [cureus.com]
Most patients recover without treatment, but some of them remain dyspneic and fatigued for months. Conversely, chronic pulmonary histoplasmosis follows exposure in patients with underlying lung diseases. [hindawi.com]
The following day, he started to feel fatigued with fevers, anorexia, odynophagia, and nausea but denied vomiting. His medical history included hypertension and he had no surgical history. He had recent prolonged traveling. [journals.lww.com]
Patients may present with shortness of breath (dyspnea), fatigue or loss of stamina, cough with blood (hemoptysis) or without, chronic chest (pleuritic) pain, recurrent pulmonary infections or pneumonias, difficulty swallowing (dysphagia), or swelling [rarediseases.org]
- Multiple Organ Dysfunction Syndrome
Complications Complications of DNM were recorded in 12 patients (70.6%) and included multiple organ dysfunction syndrome (MODS) in 6 (35%), of whom 5 initially presented in a state of septic shock. [doi.org]
Respiratoric
- Pneumonia
Usually a consequence of perforation of the oesophagus (endoscopic procedures, tumours), rarely a complication of pneumonia/mediastinitis (possibly lung abscess, empyema) or even as a complication of coemphysitis. [wikilectures.eu]
Indhold DISEASES OF THE CIRCULATORY APPARATUS 2 PART II 36 SECTION I 42 PART III 68 PART IV 139 DISEASES OF THE CIRCULATORY APPARATUS 147 PART V 156 SECTION II 173 Interstitial pneumonia and retraction of the lungs 10 Pulmonary abscess 312 Pulmonary gangrene [books.google.dk]
Empyema is a suppurative infection of the pleural cavity that is usually related to extension of a necrotizing pneumonia or lung abscess. [cancertherapyadvisor.com]
Here, we will present the evaluation and follow-up of a teenage girl presented with recurrent right lobe pneumonia which was finally diagnosed as FM. 2. [hindawi.com]
- Stridor
Given lack of stridor, shortness of breath, or inability to tolerate secretions, there was no immediate concern for airway compromise. [hindawi.com]
Symptoms commonly referred to are fever, pain and sepsis; cranial nerve deficits are common, as is trismus and stridor; erosion into adjacent hypopharynx, oesophagus or vascular structures may occur. [academic.oup.com]
Stridor ( n = 1), swelling of the face ( n = 1), thoracic pain ( n = 1) and shoulder pain ( n = 1) were rarely reported. The main clinical findings were fever in all patients and swelling/redness of the pharynx/larynx ( n = 14, 82%). [doi.org]
Idiopathic fibrosing mediastinitis in a 38-year-old man with intermittent stridor. Linear tomogram shows diffuse narrowing of the trachea and both main bronchi and a soft-tissue mass encasing the distal trachea. Figure 13a. [pubs.rsna.org]
- Exertional Dyspnea
Symptoms resulting from involvement of the pulmonary vessels include progressive or exertional dyspnea and hemoptysis. Chronic occlusion of pulmonary veins can result in secondary pulmonary arterial hypertension and cor pulmonale. [pulmonologyadvisor.com]
Patients with pulmonary venous occlusion can present with progressive or exertional dyspnea as well as with hemoptysis. This pattern of symptoms has been called the “pseudo-mitral stenosis syndrome.” [pubs.rsna.org]
- Pleuritic Pain
Patients may present with shortness of breath (dyspnea), fatigue or loss of stamina, cough with blood (hemoptysis) or without, chronic chest (pleuritic) pain, recurrent pulmonary infections or pneumonias, difficulty swallowing (dysphagia), or swelling [rarediseases.org]
Gastrointestinal
- Regurgitation
Echocardiography suggested new-onset pulmonary hypertension and moderate tricuspid regurgitation. [ahajournals.org]
Odynophagia (painful swallowing) and later dysphagia (resulting in regurgitation and aspiration) is invariably reported in most published series. [clinicsinsurgery.com]
Clinical symptoms include high fever, dysphagia, dispnea, neck stiffness, esophagus regurgitation, spontaneous draining of airways with suction, laryngeal spasm, bronchial erosion and jugular vein thrombosis (4). [annalidistomatologia.com]
Cervical abscess can also occur; in these cases, symptoms like dysphagia, odynophagia, dysphonia, regurgitation and cervical skin edema also appear. [scielo.br]
- Abdominal Pain
He denied smoking, drinking alcohol, excessive caffeine consumption, substance use, recent travel, cough, fever, chills, night sweats, hemoptysis, weight loss, joint pain, rash, nausea, vomiting, abdominal pain and syncopal episodes. [cureus.com]
Cardiovascular
- Hypertension
The patient had compression of his pulmonary artery due to fibrosing mediastinitis and findings of pulmonary hypertension on the examination and by echocardiography. [clinicalimagingscience.org]
[…] rarer disorder of unknown etiology, although several suspected causes such as granulomatous diseases, characterized by fibrous tissue proliferation within the mediastinum, leading to respiratory and cardiac failure by bronchial obstruction or pulmonary hypertension [ncbi.nlm.nih.gov]
Skin
- Erythema
After 48 h, she reported to the general hospital emergency department with erythema over the sternal notch, neck pain and fever. [archbronconeumol.org]
[…] mediastinum contains no major structures posterior mediastinum vessels descending aorta azygous venous system other structures esophagus thoracic duct Presentation Symptoms chest pain fever tachycardia Physical exam purulent discharge from the wound wound erythema [step2.medbullets.com]
Physical exam was notable for absence of distress, mild tenderness, and erythema to anterior neck left greater than right, poor dentition, symmetrical tonsillar swelling with no uvular deviation, and pharyngeal erythema. [hindawi.com]
Oedema and/or erythema of the neck and face may be found. There may be crepitus of the skin of the chest and neck due to surgical emphysema. The mouth should be examined for evidence of pharyngeal infection or foreign bodies. [patient.info]
His throat was swollen and painful at palpation, but no erythema was seen. During pulmonary investigation, pleural rubs were heard, and the abdominal survey revealed a painful upper abdomen. [jcm.asm.org]
Psychiatrical
- Suggestibility
Certain findings may be present which suggest the diagnosis. [infectiousdiseaseadvisor.com]
Echocardiography suggested new-onset pulmonary hypertension and moderate tricuspid regurgitation. [ahajournals.org]
Review of literature suggests that the isolated pathogens are rare in this setting and are most likely not related to oropharyngeal contamination during bronchoscope insertion. [ncbi.nlm.nih.gov]
Workup
Mediastinitis can be diagnosed clinically based on history and clinical presentation. A computed tomography (CT scan) or a chest x-ray can also confirm the diagnosis [9].
Patients with a history of thoracic surgery may undergo a needle aspiration biopsy; a procedure in which a needle is inserted through the sternum to retrieve fluid that can be sent for culture and examination under a microscope.
X-Ray
- Pulmonary Infiltrate
[…] of the central mass or associated lymph nodes (especially if there has been preceding histoplasmosis) Tracheobronchial narrowing Pulmonary infiltrates The following are a collection of radiological findings demonstrating the presence of fibrosing mediastinitis [wikidoc.org]
Findings included a mediastinal or hilar mass (7/7), calcifications of the central mass or in associated lymph nodes (6/7), tracheobronchial narrowing (5/7), and pulmonary infiltrates (4/7). [ajronline.org]
diffuse form Other findings include: calcifications of the central mass or associated lymph nodes: especially if there has been preceding histoplasmosis tracheobronchial narrowing 2,4 pulmonary infiltrates 2 MRI The pattern of involvement is essentially [radiopaedia.org]
Pulmonary infiltrates with mediastinal lymphadenopathy should raise the suspicion for histoplasmosis. Diagnosis can be made rapidly by serological tests, staining, and culture of bronchoalveolar lavage fluid and, in rare cases, biopsy. [ahajournals.org]
[…] debridement on patient mortality, J Thorac Cardiovasc Surg, 2000, vol. 119 (pg. 260 - 267 ) [11] Descending necrotizing mediastinitis: a retrospective surgical experience, Eur J Cardiovasc Surg, 1999, vol. 16 (pg. 200 - 205 ) [12] Ludwig angina, empyema, pulmonary [academic.oup.com]
Microbiology
- Wuchereria Bancrofti
Other rare causes of fibrosing mediastinitis include exposure to tuberculosis, aspergillosis, Wuchereria bancrofti, Blastomyces dermatitidis, and radiation therapy.2 Some forms of fibrosing mediastinitis are associated with autoimmune disorders. [ahajournals.org]
Treatment
Protection of the respiratory airway is one of the most important initial goals of treatment. The patient should not be placed in the CT scanner if the airway has not been secured. Unfortunately, swelling in the soft tissue can impede airway protection and may require fiber-optic aid. Intubation can also be further complicated by laryngospasm, trauma to the retropharyngeal wall or aspiration of pus. Urgent cricothyrotomy or tracheostomy are other options in case of severe complications.
Septic shock is common and patients require extensive fluid resuscitation upon presentation, in addition to antibiotic administration and the enforcement of sepsis protocols.
The most important part of management in the emergency setting is the prompt diagnosis. The latter can considerably improve outcomes. The differential diagnosis of mediastinitis is broad and clinical symptoms are not always clear cut. Other potential diseases that can explain the clinical picture include pneumonia, pharyngitis, acute cardiovascular disease and isolated pharyngeal abscess.
After stabilization, patients need to be transferred as soon as possible from the emergency department for surgical operation. The goal of surgery is the removal of all necrotic tissue, as well as the examination of the structures and organs within the mediastinum. Surgery is performed with a cervical approach and consists of a thoracotomy [10]. Pus and necrotic substance should be drained and any esophageal rupture needs to be closed.
Prognosis
Mediastinitis has elevated mortality, with figures ranging from 11.1% up to 50% in some case series, and reaching 67% in patients with comorbidities. Descending necrotizing mediastinitis tends to be more severe with mortality levels between 11.1% and 34.9%.
Prognosis can be improved if the disease is caught early and treated immediately and aggressively. Preventive measures can also help in avoiding the development of the condition, particularly following surgeries in the thorax area [1].
Etiology
Mediastinitis has a wide range of causes. These include esophageal rupture, ingestion of a foreign body such as a fish or a chicken bone, infection subsequent to surgery in the thorax as well as medical errors during procedures involving the esophagus or the trachea such as upper endoscopy, surgery in the esophagus, dilatation of the esophagus, transesophageal biopsy, dilatation of the trachea, bronchoscopy and transbronchial biopsy. Infections of the head and neck that can also cause mediastinitis usually affect the pharynx, the sinuses, the teeth or the tonsils [2] [3]. The disease may also very rarely be seen as a complication of laparoscopic cholecystectomy.
It can sometimes result when performing an intubation procedure and the esophagus or the hypopharynx is perforated. In these cases, symptoms appear directly after intubation or, in rare instances, they may manifest much later. The condition should be suspected if the state of the patient worsens significantly with circulatory collapse and evidence of sepsis.
Although the most commonly involved organisms are bacteria, mediastinitis can also be caused by infections with fungi, particularly candida species. Infection with candida occurs in 0.3% of all cases of cardiothoracic surgery.
Mediastinitis caused by tuberculosis should be suspected in patients with a history of the disease. It usually takes place when a lymph node ruptures within the mediastinum. Diagnosis is challenging since patients are commonly asymptomatic initially or may present with very few signs and symptoms. It is usually established with imaging modalities such as MRI.
Fibrosing mediastinitis is a very rare disease, caused by an exaggerated fibrotic reaction. It follows granulomatous disease or histoplasmosis. Typical symptoms result from pressure over structures and organs present within the mediastinum and include shortness of breath, cough, obstruction of the superior vena cava, pain in the chest and hemoptysis.
Epidemiology
Mediastinitis has become a rare disease in the developed world after the introduction of antibiotics and appears almost exclusively in patients who have undergone cardiothoracic surgery, particularly heart transplants. Nonetheless, the condition can still be commonly encountered in developing nations among patients who suffer from infections in the head and neck area.
One study suggests that in a sample of 10,000 subjects with a history of cardiothoracic surgery, the incidence of the condition was reported to be 1% [4]. Other studies report that it is six times more common among males than females, and tends to affect patients in their third and fifth decades, although cases involving patients who are as young as 2 months and older than 80 years have been also described.
Pathophysiology
Infections in the mediastinum can only take place if there is a breach to the normal structures and organs contained in it. This commonly occurs after injury to the trachea, the sternum, the bronchi and the esophagus. It can also take place when infections from the cervical and pharyngeal regions spread in a downward direction.
Descending necrotizing mediastinitis refers to an extension of the infection from the cervical and head area into the mediastinum and is usually the most common cause in the developing world. Some common descending infections involved in mediastinitis are sinusitis, pharyngeal abscess, odontogenic infections and various other ear, nose and throat infections.
The infectious spread is the most devastating form of mediastinitis. The infection has a tendency to spread in the downward direction because of the effects of gravity, negative intrathoracic pressure, and normal breathing. The condition is very prevalent in the developing world because of poor access to medical care, resulting in ineffective treatment of the infection [5] [6].
Causes of direct injury are diverse and include ingestion of foreign bodies such as chicken or fish bones, a motor vehicle accident, malignancy, surgery in the thorax, Boerhaave syndrome, dilatation of the trachea or the esophagus, bronchoscopy, endoscopy and endotracheal intubation.
The infection associated with mediastinitis is polymicrobial in nature, with the involvement of both aerobic and anaerobic organisms. However, obligates anaerobes are 10 times more common than aerobes. Bacteroides species is the most frequently involved anaerobe and streptococcus is the most common one. A range of other species has been implicated such as fusobacterium, staphylococcus, escherichia coli, haemophilus influenzae, enterobacter cloacae, peptostreptococcus, pseudomonas aeruginosa, and histoplasmosis. Mediastinitis with methicillin-resistant staphylococcus aureus has been recently identified, raising great concern [7].
Prevention
It is important to follow medical advice after surgery. In case a wound opens or there is associated swelling and fluctuance, the patient needs to be in immediate contact with his surgeon. The patient should also measure regularly his temperature and report any abnormalities to the medical team.
Individuals with diabetes should have their blood sugar levels very well controlled. Even patients normally on oral medication may need insulin injections to decrease the risk of infections.
Patients who receive radiation therapy after surgery are also at increased risk. They require continuous monitoring and follow-up to detect any infection or a breakdown in the wound. This is essential in the prevention of severe complications.
Other preventive measures include wearing a supporting bra, especially for obese patients or female patients with large breasts. Increased weight can lead to elevated stress over the wound, increasing the risk of poor wound healing.
Patients should also not use any creams, ointments or lotions before receiving appropriate medical advice. Antibacterial products are not recommended and may actually worsen the healing process. In addition, patients are generally advised to restrict movement and the lifting of heavy weights.
Summary
Mediastinitis is an infection of the mediastinum that can result from either a damage to the structures within it or from a spread of the infection from the head and neck region. In the developing world, the most common cause is an uncontrolled infection, most frequently involving the teeth and oral cavity, and spreading in a downward fashion to the mediastinum [1]. In contrast, most cases in the developed countries occur after an injury; for example, a surgery in the thorax or a motor vehicle accident. Patients develop symptoms gradually before presenting to the emergency department. History taking is the most critical step in establishing the diagnosis, in addition to the overall clinical picture. Nonetheless, magnetic resonance imaging (MRI) can be used to confirm the diagnosis. Mediastinitis requires urgent treatment with fluid resuscitation and antibiotic administration, after securing the airway. Patients are eventually referred for surgical management, which consists of debridement and exploration of the mediastinal area. Mediastinitis has a high mortality rate, especially when comorbidities are also present.
Patient Information
Mediastinitis is a severe infection of the mediastinum that can occur after injury or after the spread of infection from the head and neck area into the mediastinum. In the developing world, the condition most commonly occurs in conjunction with an infection in the hand and neck, most frequently in the teeth and the oral cavity. In contrast, an injury is the most common cause of mediastinitis in the developed world especially following surgery in the thorax. Patients generally develop gradual symptoms such as shortness of breath, confusion, fever and chills, swelling in the neck, pain in the chest and upon swallowing. They frequently have a history of infection, surgery in the thorax, a motor vehicle accident or an interventional procedure such as an endoscopy (a procedure used to visualized the digestive tract), bronchoscopy (procedure employed to look into the respiratory airways) or malignancy. Treatment of the condition is emergent and the doctors pay particular attention to securing the respiratory airway, sometimes with intubation. Fluid resuscitation is also very important since many patients may show signs of collapse due to the severity of the infection (sepsis). Patients should also be referred for surgery, in which necrotic tissue is removed and the thorax is explored to ensure the status of critical organs and structures in the area. The development of mediastinitis can be prevented if patients follow medical advice and recommendation after surgery and if they closely monitor incision wounds. Prevention of risk factors of infections such as diabetes and cardiovascular disease can also greatly help. Mediastinitis has a poor prognosis, but can be treated if diagnosis and management are prompt and aggressive.
References
- Papalia E, Rena O, Oliaro A, et al. Descending necrotizing mediastinitis: surgical management. Eur J Cardiothorac Surg. 2001 Oct; 20(4):739-42.
- Sichel JY, Attal P, Hocwald E, et al. Redefining parapharyngeal space infections. Ann Otol Rhinol Laryngol. 2006 Feb; 115(2):117-23.
- Collin J, Beasley N. Tonsillitis to mediastinitis. J Laryngol Otol. 2006 Nov; 120(11):963-6. Epub 2006 Jul 6.
- Eklund AM, Lyytikainen O, Klemets P, et al. Mediastinitis after more than 10,000 cardiac surgical procedures. Ann Thorac Surg. 2006 Nov; 82(5):1784-9.
- Scaglione M, Pezzullo MG, Pinto A, et al. Usefulness of multidetector row computed tomography in the assessment of the pathways of spreading of neck infections to the mediastinum. Semin Ultrasound CT MR. 2009 Jun; 30(3):221-30.
- Cirino LM, Elias FM, Almeida JL. Descending mediastinitis: a review. Sao Paulo Med J. 2006 Sep 7; 124(5):285-90.
- Simsek Yavuz S, Sensoy A, et al. Methicillin-Resistant Staphylococcus aureus Infection: An Independent Risk Factor for Mortality in Patients with Poststernotomy Mediastinitis. Med Princ Pract. 2014 Aug 12.
- Rehman SM, Elzain O, Mitchell J, et al. Risk factors for mediastinitis following cardiac surgery: the importance of managing obesity. J Hosp Infect. 2014 Jul 21.
- Scaglione M, Pinto A, Giovine S, et al. CT features of descending necrotizing mediastinitis--a pictorial essay. Emerg Radiol. 2007 Jun; 14(2):77-81.
- Chen KC, Chen JS, Kuo SW, et al. Descending necrotizing mediastinitis: a 10-year surgical experience in a single institution. J Thorac Cardiovasc Surg. 2008 Jul; 136(1):191-8.