Mediastinal Granuloma and Mediastinal Fibrosis

Abstract

Mediastinal granuloma/mediastinal fibrosis is a chronic inflammatory disease of the mediastinum. Mediastinal granuloma is the abnormal enlargment of mediastinal lymph nodes by granulomatous inflammation, is usually asyptomatic or minimally symptomatic, and is often detected on chest radiographs taken for other reasons. In contrast, mediastinal fibrosis is extensive fibrous tissue throughout the middle mediastinum causing compression, encasement, or invasion of the large bronchi, superior vena cava, pulmonary veins, or esophagus, often with serious clinical consequences. Some patients may exhibit a clinical entity characterized by enlarged fibrotic and/or calicified lymph nodes with a variable amount of fibrosis that may be asymptomatic, or may cause symptoms by compression or invasion of structures in the mediastinum. Clinical manifestations may be due to superior vena cava (SVC) obstruction, esophageal compression, large airway involvement, pulmonary artery or pulmonary vein narrowing, or laryngeal or phrenic nerve impingement. Definitive diagnosis is traditionally made on the basis of a surgical exploration and biopsy, either a mediastinoscopy or thoracotomy; however, characteristic findings on computed tomography (CT) of the chest may be sufficient for a diagnosis in a certain number of cases. The best therapy is unknown. Antifungal therapy and corticosteroids have been reported effective in some cases. Surgical resection of localized mediastinal granuloma or fibrosis causing symptoms is often effective. However, surgical resection of extensive mediastinal fibrosis usually is not feasible.

Mediastinite esclerosante no diagnóstico diferencial de tumores mediastinais

“…The continuous release of inflammatory or antigen material by cellular elements that constitute the process would stimulate fibroblastic activity in the more peripheral zones, leading to the formation and uncontrolled deposition of collagen, taking on a hilar and paucicellular aspect. (1) Mediastinal sclerosis might even be accompanied by retroperitoneal fibrosis, sclerosing cholangitis, Riedel's thyroiditis, orbital pseudotumor or keloids. Therefore, it is believed that there is a genetic predisposition associated with the HLA-A2 system, leading to an altered immune response.…”

“…Therefore, it is believed that there is a genetic predisposition associated with the HLA-A2 system, leading to an altered immune response. (1,4) The clinical profile is caused by the compression, entrapment or invasion of mediastinal structures. The following are the sites that are most often affected: the right paratracheal region (leading to superior vena cava syndrome and compression of the azygous vein); the subcarinal lymph nodes (the lateral extension obstructs the bronchi and the pulmonary artery, the anterior extension obstructs the pulmonary vein, and the posterior extension affects the esophagus); and the right pulmonary hilum.…”

“…Initial symptoms can include cough, dyspnea, hemoptysis and chest pain. (1,5) The principal complication of mediastinal sclerosis is superior vena cava syndrome, which is characterized by venous distention (of the veins of the neck and upper limbs), edema (of the upper extremities, neck and face), onset of collateral circulation (in the chest and back) and facial plethora. This occurred in all of the cases presented herein.…”

“…Other causes include: actinomycosis, syphilis, infection with Aspergillus flavus or Wuchereria bancrofti, as well as coccidioidomycosis, zygomycosis, nocardiosis, sarcoidosis, silicosis, trauma and use of methysergide. (1)(2)(3) It is usually difficult to make an accurate diagnosis of this rare condition using minimally invasive methods, and exploratory surgery is often needed in order to make a definitive diagnosis. (1) Herein, we describe three cases of sclerosing mediastinitis that were similar in their presentation and were diagnosed using median sternotomy.…”

“…(1)(2)(3) It is usually difficult to make an accurate diagnosis of this rare condition using minimally invasive methods, and exploratory surgery is often needed in order to make a definitive diagnosis. (1) Herein, we describe three cases of sclerosing mediastinitis that were similar in their presentation and were diagnosed using median sternotomy. Physiopathological aspects, clinical profiles and available treatments are discussed.…”