Mediastinal Cryobiopsy for Pathological Diagnosis of Fibrosing Mediastinitis-Associated Pulmonary Hypertension.

INTRODUCTION: Fibrosing mediastinitis is a benign but fatal disorder characterized by the proliferation of fibrous tissue in the mediastinum, causing encasement of mediastinal organs and extrinsic compression of adjacent bronchovascular structures. FM-associated pulmonary hypertension (FM-PH) is a serious complication of FM, resulting from the external compression of lung vessels. Pathologic assessment is important for etiologic diagnosis and effective treatment of this disease. CASE PRESENTATION: A 59-year-old male patient presented at our hospital and was diagnosed with FM-PH. He declined surgical biopsy that is the reference standard for pathologic assessment, in consideration of the potential risks. Therefore, an endobronchial ultrasound examination was performed, which identified the subcarinal lesion. Under ultrasound guidance, four needle aspirations were carried out, followed by one cryobiopsy. Histopathological examination of transbronchial needle aspiration specimens was inconclusive, while samples from cryobiopsy suggested a diagnosis of idiopathic FM. Further immunophenotyping demonstrated the infiltration of lymphocytes, macrophages, and FOXP3-positive cells in FM-PH. CONCLUSION: Mediastinal cryobiopsy might be a novel and safe option for FM-PH patients who are unwilling or unsuitable for surgical procedure.

Potential Value of FAPI PET/CT in the Detection and Treatment of Fibrosing Mediastinitis: Preclinical and Pilot Clinical Investigation.

Fibrosing mediastinitis (FM) is a rare proliferative disease within the mediastinum that leads to pulmonary hypertension, which has been regarded as a major cause of death. This study aims to evaluate the potential value of fibroblast activation protein inhibitor (FAPI)-PET/CT in the integration of diagnosis and treatment of FM through targeting FAPI in fibrosis rats and provide a theoretical basis for clinical management of FM patients. By performing a 18F-FAPI PET/CT scan, the presence of FAPI-avid in the fibrotic lesion was determined. Through a fibrosis rat model, 18F-FAPI-74 was used for lesion imaging and 177Lu-FAPI-46 was utilized to investigate the potential therapeutic effect on FM in vivo. In addition, biodistribution analysis and radiation dosimetry were carried out. With the 177Lu-FAPI-46 pharmacokinetic data of rats as the input, the estimated dose for female adults was computed, which can provide some useful information for the safe application of radiolabeled FAPI in the detection and treatment of FM in patients. Then, major findings on the use of FAPI PET/CT and SPECT/CT in FM were presented. 18F-FAPI-74 showed a high-level uptake in FM lesions of patients (SUVmax 7.94 ± 0.26), which was also observed in fibrosis rats (SUVmax 2.11 ± 0.23). Consistently, SPECT/CT imaging of fibrosis rats also revealed that 177Lu-FAPI-46-avid was active for up to 60 h in fibrotic lesions. In addition to this robust diagnostic performance, a possible therapeutic impact was evaluated as well. It turned out that no spontaneous healing of lesions was observed in the control group, whereas there was complete healing on day 9, day 11, and day 14 in the 30, 100, and 300 MBq groups, respectively. With a significant difference in the free of event rate in the Kaplan-Meier curve among four groups (P < 0.001), a dose of 300 MBq displayed the best therapeutic effect, and no obvious damage was observed in the kidney. Furthermore, organ-absorbed doses and an effective dose (0.4320 mSv/MBq) of 177Lu-FAPI-46 presumed for patients were assumed to give a preliminary indication of its safe use in clinical practice. In conclusion, 18F-FAPI-46 PET/CT can be a potentially valuable tool for the diagnosis of FM. Of note, 177Lu-FAPI-46 may be a novel and safe radiolabeled reagent for the integration of diagnosis and treatment of FM.

A rare cause of pulmonary hypertension: Idiopathic fibrosing mediastinitis obstructing right pulmonary artery and pulmonary veins.

Fibrosing mediastinitis is caused by a proliferation of fibrous tissue in the mediastinum with encasement of mediastinal viscera and compression of mediastinal bronchovascular structures. Pulmonary hypertension (PH) may occur as a severe complication of the disease. Herein, we report a patient diagnosed with fibrosing mediastinitis and pulmonary hypertension, whose imaging tests showed obstruction of right pulmonary artery and veins.

Comparison of fibrosing mediastinitis patients with vs. without markedly increased systolic pulmonary arterial pressure: a single-center retrospective study.

INTRODUCTION: Fibrosing mediastinitis (FM) complicated with pulmonary hypertension (PH) has been considered as an important cause of morbidity and mortality. This study was designed to observe the possible effects of abnormal hemodynamics on patients by conducting a between-group comparison according to the presence of markedly increased systolic pulmonary arterial pressure (SPAP), so as to provide more information for clinical management. MATERIALS AND METHODS: Fifty-one patients with clinically diagnosed FM were divided in two groups (SPAP < 50 mmHg group; SPAP ≥ 50 mmHg group) and retrospectively included in the study. Data mainly including demographic factors, echocardiographic data, results of right heart catheter and computed tomography (CT) examination were retrieved from the medical database. Echocardiographic parameters pre- and post- balloon pulmonary angioplasty (BPA) treatment were also collected in 8 patients. RESULTS: Significant changes in cardiac structure, hemodynamics and cardiac function were detected in patients complicated with markedly increased SPAP. Patients in the SPAP ≥ 50 mmHg group had increased right heart diameter, right heart ratio and velocity of tricuspid regurgitation (VTR) (p < 0.05). Deteriorated right heart function was also observed. There was no significant difference in CT findings between the two groups, except that more patients in the SPAP ≥ 50 mmHg group had pleural effusion (p < 0.05). After primary BPA in 8 patients, improvement in the right atrium proportion was observed. CONCLUSIONS: Changes due to significantly increased SPAP in patients with FM include adverse structure and function of the right heart, but differences in CT findings were not significant. Echocardiography has advantages as a noninvasive tool for the evaluation of cardiac structure, function and hemodynamics in patients with FM.

Extensive fibrotic wrapping of the heart: a rare echocardiographic diagnosis.

BACKGROUND: Fibrosing mediastinitis (FM) is considered a benign disease, but it can be fatal if progression leads to compression of the hilum of the lungs or invasion of the heart. Echocardiographic reports of this disease are very rare. CASE PRESENTATION: We present a 14-year-old male patient whose non-enhanced chest computed tomography showed unclear soft-tissue dense lesions in the anterior superior mediastinum. Echocardiography showed the heart was extensively wrapped by soft tissue lesions. The histology confirmed FM. CONCLUSIONS: When FM affects the heart, echocardiography can help to characterize the disease and aid in the diagnosis. Echocardiography should be considered an important tool to follow the progression of this disease and guide the therapeutic approach.

Acute mediastinitis, mediastinal granuloma, and chronic fibrosing mediastinitis: A review.

Acute mediastinitis is a rare infection that carries high morbidity and mortality. They are complications seen most often with deep sternal wound infections from surgeries with median sternotomies, oropharyngeal and odontogenic infections and esophageal perforations. These conditions should be promptly recognized and treated. Mediastinal granulomas are focal, mass-like lesions commonly resulting from prior granulomatous infections. They are regarded as benign, self-resolving lesions however can cause complications by compression of adjacent mediastinal structures. Chronic fibrosing mediastinitis is a rare, diffuse fibroinflammatory process most often seen with granulomatous infections and carries a worse prognosis than mediastinal granulomas especially when adjacent mediastinal structures are compromised. In this review, we discuss the epidemiology, etiology, clinical presentation, treatment and prognosis of acute mediastinitis, mediastinal granulomas, and chronic fibrosing mediastinitis.

Idiopathic focal fibrosing mediastinitis with unilateral pulmonary arterial and venous involvement.

We report a case of a 1-year-old girl where computed tomography (CT) angiography demonstrated presence of ill-defined heterogenous soft tissue thickening obliterating the mediastinal fat planes in right peri-hilar region and encasing the hilar right pulmonary artery and its segmental branches leading to marked narrowing with nonvisualization of the right-sided pulmonary veins. The case highlights the features of fibrosing mediastinitis as well as the role of CT angiography in the diagnosis and accurate depiction of the extent of involvement of the mediastinal vasculature and airways.

A review of endovascular stenting for superior vena cava syndrome in fibrosing mediastinitis.

Fibrosing mediastinitis (FM) is a rare disorder of inflammation and fibrosis involving the mediastinum. The formation of fibroinflammatory mass in the mediastinum can lead to obstruction of mediastinal structures and cause severe debilitating and life-threatening symptoms. Superior vena cava syndrome (SVCS) is a dreaded complication of FM with no medical therapy proven to be efficacious. Spiral vein grafting has long been utilized as first-line therapy for SVC syndrome due to FM. Endovascular repair with stents and angioplasty for malignant causes of SVC syndrome is well established. However, there are limited data on their utility in SVC syndrome due to FM. We present two cases of SVC syndrome due to FM treated with endovascular stenting and a detailed review of current literature on its utility in SVCS due to benign causes.

Pulmonary Artery Stenosis in a Patient with Prior Histoplasmosis and the Discovery of Complications.

Pulmonary hypertension (PH) results from varied etiologies, leading to progressive symptoms and limiting physical activity and quality of life, with associated morbidity and mortality. External compression of the pulmonary artery (PA) is a rare cause of PH and may give the clinician cause to investigate compression of nearby structures. In this E-Challenge, the authors present a case of PA stenosis in a patient with prior histoplasmosis scheduled for left PA stenting. However, because the pulmonary veins were not well-visualized on chest computed tomography, the anesthesia team performed a perioperative transesophageal echocardiogram (TEE) to help differentiate the causes of PH. TEE revealed external compression of the pulmonary veins. This case highlights the value of pathophysiologic understanding, preoperative planning, and the effect of echocardiography on clinical management and patient safety. In this case, TEE prevented possible morbidity and mortality.

Fungal fibrosing mediastinitis in pregnancy - Case report with review of literature.

Fibrosing mediastinitis (FM) is characterized by extensive and invasive fibro-inflammatory proliferation, triggered by a delayed hypersensitivity reaction to variety of infective or noninfective stimuli. The infective agents often have a geographic distribution such as Histoplasma capsulatum in North America and Mycobacterium tuberculosis in Asian regions. In few reports, the mediastinitis is caused by fungi, particularly Aspergillus species. We report the first case of possible aspergillous FM in a young pregnant woman.

Fibrosing Mediastinitis Caused by Histoplasmosis in an Adolescent.

Fibrosing mediastinitis (FM) is a rare, potentially progressive disease resulting from an idiosyncratic immune response to a variety of stimuli that lead to fibrous infiltration of the mediastinum and possible narrowing of the bronchovascular structures. We report an unusual case of FM in a pediatric patient presenting as myopericarditis and progressing to pericardial thickening and encasement of the mediastinal vascular structures needing surgical intervention. Imaging, including transthoracic echocardiography, cardiac computed tomography, and cardiac magnetic resonance played a crucial role in the diagnosis, assessment, and follow-up. Contrast-enhanced computed tomography can be especially helpful to demonstrate potential findings associated with FM.

A rare sequelae of esophageal perforation: Fibrosing mediastinitis.

Fibrosing mediastinitis (FM) is a rare disease caused by different causes. If left untreated, the prognosis is poor. The common causes of FM are Tuberculosis and Histoplasma capsulatum infection. Esophageal perforation is also a rare condition that is often easily under- and mis-diagnosed due to the lack of specificity of symptoms. Here we report a case of FM caused by esophageal perforation.

Post-tuberculosis fibrosing mediastinitis: A report of 3 cases.

Fibrosing mediastinitis is a rare entity generally caused by granulomatous disease. Most cases develop as a complication of histoplasmosis. Association with tuberculosis has been rarely documented. We report the case of 3 young patients who presented with superior vena cava syndrome several years after treated tuberculosis. Biological, radiological, and histological investigations led to the diagnosis of fibrosing mediastinitis.

Fibrosing mediastinitis resulting in unilateral pulmonary artery hypertension.

Fibrosing mediastinitis (FM), a rare disorder that is further classified as excessive fibrous tissue that occurs within the mediastinum. Classically, presenting with manifestations dependent on where the fibrous tissue is located. In rare instances, compression of pulmonary vasculature can lead to Pulmonary Hypertension. Pulmonary Hypertension- Fibrosing Mediastinitis (PH-FM) represents a rare complication with minimal available data on incidence. In regards to all-cause mortality, no specific data regarding the prognosis of PH-FM exist. With the scarcity of data, this case aids in the advancement of literature due to unique unilateral obstruction and the need for further analysis on our current treatment.

Pulmonary vascular stenosis scoring in fibrosing mediastinitis.

Aims: This study aims to develop a scoring system for evaluating the degree of pulmonary vascular stenosis in fibrosing mediastinitis (FM). Methods and results: A retrospective single-centre study was conducted on 56 patients with FM in China between April 2014 and August 2021. The involvement of pulmonary vessels in patients with FM was assessed using dual-phase computed tomography pulmonary angiography, and we found that 85.7% of the patients had both pulmonary artery (PA) and vein (PV) involvement. PA involvement was mainly located proximal to both the upper PA and the bilateral basal trunk levels in the lower lungs. The involvement of the superior PV was more common than that of the inferior PV, and the right inferior PV was the least involved. Most of these lesions exhibited moderate or severe stenosis. Additionally, a scoring system for evaluating the degree of pulmonary vascular stenosis was developed. A correlation analysis revealed a negative correlation between the final pulmonary vascular score and the pulmonary arterial pressure, pulmonary vascular resistance, and maximum tricuspid regurgitation velocity. The calculated score of 17.1 was the best cut-off value for the diagnosis of mild and severe pulmonary hypertension (PH). Conclusion: We successfully developed a scoring system for pulmonary vascular stenosis that can be used to evaluate the severity of pulmonary vessel involvement and PH. This scoring system may be relevant in the future development of target-based strategies for percutaneous interventions.

A retrospective analysis of transudative pleural effusion due to fibrosing mediastinitis.

BACKGROUND: Pleural effusion caused by fibrosing mediastinitis is rarely reported. This study aimed to summarize the clinical manifestations, diagnosis and treatment of transudative pleural effusion due to fibrosing mediastinitis. METHODS: Medical records and follow-up data of 7 patients with transudative pleural effusion due to fibrosing mediastinitis in Beijing Chaoyang Hospital between May 2014 and Feb 2018 were retrospectively analyzed. RESULTS: These patients included 4 males and 3 females, with an average age of (64 ± 9) years. There were 3 left-sided effusions, 2 right-sided effusions and 2 bilateral effusions. Previous or latent tuberculosis was found in 6 patients. Pulmonary hypertension was indicated by echocardiography in all the 7 patients. Computed tomography pulmonary angiography (CTPA) of all the 7 cases showed increased soft tissue images visible in the mediastinum and bilateral hilus, different degrees of stenosis or occlusion in the pulmonary artery and pulmonary vein. In addition, 4 cases were found of right middle lobe atelectasis with a mediastinal window setting. There was interstitial pulmonary edema on the side of pleural effusion with a lung window setting. All the 7 patients were treated with intermittent drainage of pleural effusion combined with diuretic therapy. Five patients were treated with antituberculosis therapy. Up to now, two patients died of right heart failure and respiratory failure after 2 and 16 months respectively; The remaining 5 patients were still in follow up. CONCLUSION: Fibrosing mediastinitis can lead to pulmonary vein stenosis or occlusion, and thus cause transudative pleural effusion, which can be detected by CTPA. Pulmonary hypertension, long time of cough, and a history of tuberculosis are common in these patients. The common therapy is intermittent drainage of pleural effusion combined with diuretic therapy.

Endobronchial ultrasound-guided cautery-assisted transbronchial mediastinal cryobiopsy in the diagnosis of fibrosing mediastinitis secondary to atypical sarcoidosis: a case report.

Background: Fibrosing mediastinitis (FM) secondary to atypical sarcoidosis (atypical presentation of sarcoidosis) is rarely reported at home and abroad. Its clinical manifestations represent a lack of specificity, and the initial diagnosis is frequently difficult. In particular, this case has multiple pulmonary nodules with mediastinal lymph node enlargement and bilateral pleural effusion, and pulmonary fibrosis still exists after treatment, which is inconsistent with any clinical stage of pulmonary sarcoidosis, further increasing the diagnostic difficulty. We retrospectively analyzed the clinical data of a case of FM secondary to atypical sarcoidosis diagnosed by endobronchial ultrasound-guided cautery-assisted transbronchial mediastinal cryobiopsy (EBUS-CA-TBMCB) in Chongqing University Fuling Hospital, to improve clinicians' attention to FM and understand that EBUS-CA-TBMCB remains an effective way of etiological diagnosis. Case Description: A 70-year-old man was hospitalized with cough and dyspnea for two months. After admission, through chest computed tomography (CT), ultrasound guided bilateral lung biopsy, left parietal pleural biopsy, and EBUS-CA-TBMCB, the final diagnosis was atypical sarcoidosis secondary FM. After taking glucocorticoid orally, the patient's condition improved significantly, and was discharged from the hospital. We continued following up outside the hospital, and the patient's condition was further improved. Conclusions: The diagnosis of FM is mainly based on typical imaging manifestations. When the contrast-enhanced chest CT finds localized or diffuse soft tissue density shadows around the mediastinum and pulmonary hilum with an irregular shape, with or without calcification, particular attention should be paid to exclude FM. EBUS-CA-TBMCB, as an improved minimally invasive method, can obtain enough tissue samples for pathological diagnosis, which may be the effective biopsy method for the etiology of FM to avoid missed diagnosis and misdiagnosis in the future.

Non-IgG4-Related Fibrosing Mediastinitis Diagnosed on Core Needle Biopsy and Treated with Steroids: A Case Study and Review of the Differential Diagnoses.

OBJECTIVES: This study aimed to investigate the histological characteristics and treatment efficacy of non-immunoglobulin G4-related fibrosing mediastinitis and discuss differential diagnoses for this rare entity. METHODS: We present a case study of non-immunoglobulin G4-related fibrosing mediastinitis diagnosed on core biopsy and treated with steroids. A total of four 18-gauge core needle biopsy specimens were obtained for surgical pathology. Analysis of the patient's medical history, radiological characteristics of fibrosing mediastinitis, histological features, immunohistochemistry results, the differential diagnosis and treatment efficacy of different types of fibrosing mediastinitis was performed. RESULTS: This report describes a unique presentation of fibrosing mediastinitis (syncope and weight loss) that was concerning for malignancy. Histological, laboratory and radiographical studies confirmed the diagnosis of non-immunoglobulin G4-related fibrosing mediastinitis. The patient received corticosteroid treatment which showed marked improvement after 1 month of treatment. CONCLUSIONS: Fibrosing mediastinitis is an extremely uncommon entity with unknown pathogenesis, and it is more important to rule out malignancy and infection than to delineate between fibrosing mediastinitis and IgG4-related disease. In doing this, we may reasonably initiate a trial of corticosteroids which may prove beneficial, as in this patient. More studies on the pathogenesis of fibrosing mediastinitis are necessary to guide better directed treatments.

Pulmonary artery vasodilators for treatment of pulmonary hypertension complicating fibrosing mediastinitis.

Fibrosing mediastinitis (FM) is a heterogeneous disease characterized by sclerosing fibrosis of mediastinal structures. Pulmonary hypertension (PH) may complicate the course of the disease and can contribute significantly to the morbidity of FM. Due to the rarity and complexity of the disease, evidence-based guidelines are not currently available, and the optimal treatment approach is unknown. Management approaches should be individualized, and current techniques are often unsatisfactory. Here, we present two cases of PH complicating FM that were managed using pulmonary artery vasodilator therapy with excellent hemodynamic response.

Idiopathic Mediastinal Fibrosis: A Study of a Case Using CT and Bronchoscopic Imaging.

An uncommon illness known as fibrosing mediastinitis causes the mediastinum to grow excessively thick fibrous tissue. Fungal or idiopathic origins are the most common etiologies of pathology. In an individual suffering from chronic obstructive pulmonary disease (COPD), fibrosing mediastinitis, which resembled a bronchogenic cancer, was identified during anatomopathological examination following mediastinoscopy.