We retrospectively reviewed the radiographic findings of fibrosing mediastinitis (FM) in 33 patients.

We retrospectively reviewed the radiographic findings of fibrosing mediastinitis (FM) in 33 patients. Imaging studies included chest radiographs, comput tomographic scans, magnetic resonance imaging examinations, esophograms, ventilation perfusion scans, angiograms, and venograms. Findings include bronchial narrowing in 11 patients (33 percent) pulmonary artery obstruction/narrowing in 6 patients (18 percent) esophageal narrowing in 3 patients (9 percent) and superior vena cava obstruction/narrowing in 13 patients (39 percent) couple distinctly different radiographic patterns were identified: a localized pattern seen in 27 patients (82 percent) that often contained calcification and a diffuse pattern seen in 6 patients 18 percent) that did not contain calcification. The localized pattern is chiefly likely due to histoplasmosis and does not indicate radiographic evidence of improvement with steroid therapy. The diffuse pattern may more likely be in fact idiopathic or of a noninfectious etiology. Several patients with the diffuse pattern showed radiographic evidence of improvement with steroid therapy. CT=comput tomography; FM=fibrosing mediastinitis; MRI=magnetic resonance imaging; SVC=superior vena cava

Fibrosing mediastinitis (FM) is an excessive fibrotic reaction that befalls in the mediastinum, most commonly secondary to histoplasmosis.[1-4] This fibrotic reaction may lead to compression and sometimes occlusion of mediastinal structures[1-10] Other granulomatous diseases of that kind as tuberculosis have reportedly springed in FM.[8,9] Several examples of an idiopathic form of FM perhaps proper to a noninfectious, possibly autoimmune proces have also been described.[10,11] This idiopathic form is occasionally associated with other conditions, including retroperitoneal fibrosis,[10-12] orbital pseudotumors,[11] Riedel's sclerosing thyroiditis,[11] and methysergide therapy.[13]

MATERIALS AND METHODS

Selection of Cases

A search of the medical records at our institution revealed 33 cases of FM that had the pair radiographs and charts available for review. Twenty-five of these patients had pathologically proven FM The remaining eight patients had sufficiently characteristic radiographic findings (Weinstein et al6) to make the diagnosis without tissue sampling.

The clinical records and the following radiographic studies were reviewed: conventional chest radiographs (31 patients), chest comput tomography (CT) (24 patients), chest magnetic resonance imaging (MRI) (3 patients), esophagograms (5 patients), radionuclide profusion and ventilation studies (3 patients), venograms/angiograms (8 patients), bronchogram (1 patient), and linear tomography (2 patients).

RESULTS

Clinical Information

The average patient age was 35 years, with an age range of 13 to 64 years. Thirteen patients (40 percent) were male and 20 patients (60 percent) were female. Clinical signs and symptoms included cough in 45 percent shortness of breath/dyspnea in succession exertion in 42 percent, superior vena cava (SVC) syndrome in 39 percent hemoptysis in 27 percent chest pain in 27 percent renewed respiratory tract infections in 27 percent dysphagia in 6 percent lithoptysis in 3 percent and hoarseness in 3 percent In addition, three patients (9 percent) were asymptomatic.

Clinical follow-up of greater than 1 year was available in 23 patients. Of this clump 10 patients (44 percent) had improvement of their symptoms, 11 patients (48 percent) had no significant change, and merely 2 patients (8 percent) had progression of symptoms. No patients died as a direct follow of FM in our series.

Etiology

Etiology of FM was divided into four clusters based on various criteria. 1.Histoplasmosis or Granulomatous Disease

(14/33 Patients): This cluster of patients had either

pathologically identified caseous granulomas

(ten patients) or microorganisms consistent

with histoplasmosis (two patients) or the two (two

patients). Twelve patients in this assemblage had TB

skin standards and all were negative. 2Presum Histoplasmosis (9/33 Patients): This

collection of patients did not encounter the criteria to fit

into cluster 1. However, they did have positive

histoplasmosis serologic touchstones (four patients),

positive histoplasmosis skin experiment (two patients),

or radiographically identified calcified pulmonary

granulomas or calcified mediastinal or hilar

lymph nodes (three patients). Eight of these

patients had TB skin examples all of which were

negative. 3.Unknown (7/33 Patients): This cluster of patients

did not befitting the criteria for either group

1 or 2 4.Idiopathic With Associated Abnormality (3/33

Patients): This cluster fit none of the criteria for

clump 1 or 2 and had other conditions that may

be associated with FM[1012] common patient had

retroperitoneal fibrosis, the same had previous methylsergide

therapy, and the same had an orbital

pseudotumor with histologic features similar to

his fibrotic mediastinal process

Radiographic Findings

Tracheal Bronchial Narrowing: Tracheal narrowing was near in one patient. Bronchial narrowing was not absent in 11 patients (33 percent) Eight of these patients had narrowing becoming to circumferential encasement and the remaining four patients had narrowing to be ascribed to localized compression. Frequently, more than common part of the tracheobronchial tree was affected. The right mainstem (58 percent) left mainstem (33 percent) bronchus intermedius 33 percent) right upper lobe bronchus (25 percent) left upper lobe bronchus (16 percent) and right middle lobe bronchus (8 percent) were among those airways affected.

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