Fibrosing Mediastinitis

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 Infection and Bacterial Lymphadenitis by Gemella morbillorum Leading to Airway Perforation and a Bronchopleural Fistula

Introduction: Necrotizing bronchial infection with severe infectious lymphadenitis is infrequently encountered and most commonly ascribed to Aspergillus, Histoplasma, and Mycobacterium species. We present a unique cause of severe airway destruction with lymphadenitis and bronchopleural fistula formation by the bacterium Gemella morbillorum. Case: A 24-year-old man presented with acute symptoms of vomiting, fever, and shoulder pain. A CT of the chest demonstrated a large subcarinal mass encasing the central bronchi. The workup for malignant, fungal, and granulomatous etiologies was unrevealing, while blood cultures identified G. morbillorum. Fiberoptic bronchoscopy revealed a perforation of the right middle lobar bronchus and the formation of a bronchopleural fistula, resulting in a large hydropneumothorax with empyema. Despite antibiotic therapy, surgical intervention to repair the fistula, and ventilatory support, the progression of the bronchopleural fistula led to fatal respiratory failure. Conclusion: In cases of severe mediastinal adenopathy in a young patient, bacterial lymphadenitis should be considered in the differential diagnosis with lymphoma, germ cell tumor, granulomatosis with polyangiitis, sarcoidosis, histoplasmosis, and inflammatory myofibroblastic tumor.

Added value of spectral computed tomography quantitative parameters for differentiating tuberculosis-associated fibrosing mediastinitis from endobronchial lung cancer: initial results

OBJECTIVE

The objective of this study was to explore the added value of spectral computed tomography (CT) parameters to conventional CT features for differentiating tuberculosis-associated fibrosing mediastinitis (TB-associated FM) from endobronchial lung cancer (EBLC).

METHODS

Chest spectral CT enhancement images from 109 patients with atelectasis were analyzed retrospectively. These patients were divided into two distinct categories: the TB-associated FM group (n = 77) and the EBLC group (n = 32), based on bronchoscopy and/or pathological findings. The selection of spectrum parameters was optimized with the least absolute shrinkage and selection operator regression analysis. The relationship between the spectrum parameters and conventional parameters was explored using Pearson's correlation. Multivariate logistic regression analysis was used to build spectrum model. The spectrum parameters in the spectrum model were replaced with their corresponding conventional parameters to build the conventional model. Diagnostic performances were evaluated using receiver operating characteristic curve analyses.

RESULTS

There was a moderate correlation between the parameters ㏒(L-AEFNIC) - ㏒(L-AEFC) (r= 0.419; p< 0.0001), ㏒(O-AEF40KeV) - ㏒(O-AEFC) (r= 0.475; p< 0.0001), [L-A-hydroxyapatite {HAP}(I)] - (L-U-CT) (r= 0.604; p< 0.0001), {arterial enhancement fraction (AEF) derived from normalized iodine concentration (NIC) of lymph node (L-AEFNIC), AEF derived from CT40KeV of bronchial obstruction (O-AEF40KeV), arterial-phase Hydroxyapatite (Iodine) concentration of lymph node [L-A-HAP(I)], AEF derived from conventional CT (AEFC), unenhanced CT value (U-CT)}. Spectrum model could improve diagnostic performances compared to conventional model (area under curve: 0.965 vs 0.916, p= 0.038).

CONCLUSION

There was a moderate correlation between spectrum parameters and conventional parameters. Integrating conventional CT features with spectrum parameters could further improve the ability in differentiating TB-associated FM from EBLC.

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.

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.

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.

Mediastinal fibrosis as a late and fatal complication of treated tuberculosis mimicking a neoplastic process in a 34-year-old man

Fibrosing mediastinitis, also known as sclerosing mediastinitis, is an uncommon condition marked by abnormal proliferation of fibrous tissue in the mediastinum. This condition may accrue either as an idiopathic condition or as a complication of an underlying disease process. Its pathogenesis remains unknown. However, most reported cases are incriminating abnormal immune-mediated hypersensitivity responses to Histoplasma infection. Other rare causes include tuberculosis, blastomycosis, and an idiopathic form that may be associated with other miscellaneous conditions. CT and MR imaging play a vital role in the diagnosis and management of this disease. We present a rare case of fibrosing mediastinitis as a late complication of tuberculosis in a 34-year-old man with a prior history of mediastinal tuberculosis, mimicking initially a neoplastic mediastinal process. We will describe this clinical case in the light of the literature and point out the contribution of radiological imaging in the diagnosis of this rare pathology.

Unexpected fibrous mediastinitis in a patient with myasthenia gravis - a case report

BACKGROUND

Fibrous mediastinitis (FM) is a rare mediastinal lesion characterized by proliferation of fibrous tissue within the mediastinum. Previous reports have shown that this lesion can be caused by histoplasmosis and tuberculosis. In extremely rare cases, FM can also be caused by autoimmune diseases such as antineutrophil cytoplasmic antibody-associated vasculitis and large-vessel arteritis.

CASE PRESENTATION

In our case, we report unexpected fibrous mediastinitis found after robotic thymectomy in a patient with myasthenia gravis (MG). The preoperative imaging indicated no obvious lesion in the mediastinum and the patient denied histories of both histoplasmosis and tuberculosis. After the operation, both proliferation of fibrous tissue and ectopic germinal centres (GCs) could be found in the thymus.

CONCLUSION

This rare case might enrich our knowledge of the relationship between FM and autoimmune diseases.

Endemic mycoses in children in North America: a review of radiologic findings

Clinically significant endemic mycoses (fungal infections) in the United States (U.S.) include Blastomyces dermatitidis, Histoplasma capsulatum, and Coccidioides immitis/posadasii. While the majority of infections go clinically unnoticed, symptomatic disease can occur in immunocompromised or hospitalized patients, and occasionally in immune-competent individuals. Clinical manifestations vary widely and their diagnosis may require fungal culture, making the rapid diagnosis a challenge. Imaging can be helpful in making a clinical diagnosis prior to laboratory confirmation, as well as assist in characterizing disease extent and severity. In this review, we discuss the three major endemic fungal infections that occur in the U.S., including mycology, epidemiology, clinical presentations, and typical imaging features with an emphasis on the pediatric population.

Idiopathic fibrosing mediastinitis with esophageal varices: A case report

Fibrosing mediastinitis (FM) is a rare cause of lung fibrosis with multiple etiologies ranging from infectious to autoimmune to idiopathic. Common causes of FM include histoplasmosis and a relatively new cause of IgG4-related disease. We present a 55-year-old male with symptoms of esophageal varices, intractable hiccups, and progressive difficulty in breathing. A chest X-ray showed right lung fibrosis with pleural effusion and loss of lung volume, which was originally thought to be the sequelae of SARS-CoV-2 or metastasis, but computed tomography of the chest revealed FM. His variceal bleeding was controlled, and he was discharged home. However, treatment for FM was not pursued because the cause was not identified. Using corticosteroids may not cease the progression of the disease, and surgical options are available when symptoms persist. Idiopathic FM requires laboratory and radiological findings to exclude relevant differential diagnoses.

Chronic Tubercular Mediastinitis: A Rare Case Presentation With Subcutaneous Emphysema

Tuberculosis, histoplasmosis, various fungal infections, malignancy, and sarcoidosis are the most common causes of chronic or slowly progressing mediastinitis. Chronic mediastinitis of tubercular origin with subcutaneous emphysema is exceptionally uncommon, and the majority of cases are caused by trauma. Here we report the case of a 35-year-old chronic alcoholic male who presented to the Outpatient Department (OPD) with complaints of cough, chest pain, loss of weight, and intermittent low-grade fever for three months with no significant past medical history or family history for any respiratory diseases. He was admitted and all routine investigations were performed, which were normal including his chest X-ray, except erythrocyte sedimentation rate (ESR) which was raised. The patient's high-resolution Computed Tomography (HRCT) of the thorax was done which showed multiple pleural-based nodular lesions with few showing central cavitary nodules along with ground glass appearance. It also showed two fistulous tracks of 3.4-millimeter diameter, arising from the trachea at the T1 - T2 vertebral level and at the carina which led to the presence of air in the subcutaneous plane extending from the neck up to visualized abdomen suggestive of chronic mediastinitis with tracheal fistula, along with subcutaneous emphysema. This fistula was confirmed by video bronchoscopy as well as three-dimensional (3D) virtual bronchoscopy. A biopsy was taken, which was positive for acid-fast bacilli (AFB) stain, polymerase chain reaction (PCR) for tuberculosis, and positive tuberculin skin test. The patient was started on anti-tubercular treatment and on a follow-up visit upon completion of the intensive phase, his HRCT and video bronchoscopy showed fibrosing scarring with fistula closure.

Fibrosing Mediastinitis Causing High Degree AV Block in a Young Female Patient

A 30-year-old woman presented with presyncopal episodes and was found to have high degree atrioventricular block. Computed tomography imaging demonstrated pericardial thickening extending from the main pulmonary artery to the aortic cusps. Here we present a rare case of fibrosing mediastinitis causing high-degree atrioventricular block. (Level of Difficulty: Intermediate.).

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.

Pediatric mediastinal masses

Mediastinal masses are categorized based on the International Thymic Malignancy Interest Group (ITMIG) classification into prevascular, visceral and paravertebral compartments. The schema is based on cross-sectional imaging, mainly CT, and helps with generating a differential diagnosis based on location of the mass. Up to half of all pediatric mediastinal tumors are malignant. In this review we describe mediastinal masses that are relevant to the pediatric population, as well as the role of MR imaging of mediastinal masses and its advantages.

Pulmonary Hypertension Caused by Fibrosing Mediastinitis

Pulmonary hypertension (PH) is a progressive and severe disorder in pulmonary hemodynamics. PH can be fatal if not well managed. Fibrosing mediastinitis (FM) is a rare and benign fibroproliferative disease in the mediastinum, which may lead to pulmonary vessel compression and PH. PH caused by FM (PH-FM) is a pathologic condition belonging to group 5 in the World Health Organization PH classification. PH-FM has a poor prognosis because of a lack of effective therapeutic modalities and inappropriate diagnosis. With the development of percutaneous pulmonary vascular interventional therapy, the prognosis of PH-FM has been greatly improved in recent years. This article provides a comprehensive review on the epidemiology, pathophysiologic characteristics, clinical manifestations, diagnostic approaches, and treatment modalities of PH-FM based on data from published reports and our medical center with the goal of facilitating the diagnosis and treatment of this fatal disease.

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PH-FM, as a type of rare condition in group 5 PH, has a poor prognosis because of a lack of effective therapeutic modalities and frequent misdiagnosis and underdiagnosis.

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The most prevalent trigger of FM is H-FM in the United States and TB-FM in China.

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Imaging findings, including mismatched perfusion defects in the V/Q scan, FM dyad, and FM triad are important diagnostic clues, and clinical classification facilitates decision making in diagnosis and therapeutics.

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Because of the limited efficacy of drug therapy as well as the uncertain effectiveness and high risk of surgical treatment, endovascular interventional modality is currently the preferred therapeutic option, although procedure-related complications and intrastent restenosis after PV intervention need to be addressed.

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.

Clinical Features of Fibrosing Mediastinitis in Japanese Patients: Two Case Reports and a Literature Review

Fibrosing mediastinitis (FM) is a rare fibroinflammatory disease of the mediastinum with an etiology and clinical features that vary by world region. The characteristics of FM in Japan are still unknown. We herein report two Japanese patients with FM who were treated with corticosteroids and responded well. We also reviewed the Japanese literature on PubMed® and summarized the characteristics of 27 Japanese FM patients, including our two patients. In Japan, the predominant cases were those without a specific cause, were diffusely distributed, and responded well to corticosteroid therapy.

Extrinsic compression of coronary and pulmonary vasculature

Coronary artery disease from atherosclerosis induced stenosis remains the leading cause of acute coronary syndrome (ACS) and death worldwide, however extrinsic compression of coronary arteries from adjacent anatomical and pathological structures is an infrequent but important diagnosis to be aware of, especially given the nonspecific symptoms of chest pain that mimic angina in patients with pulmonary hypertension (PHT) and congenital heart disease. Non-invasive CT angiography is an invaluable diagnostic tool for detection of coronary artery compression, pulmonary artery dilatation and pulmonary vascular compression. Although established guidelines are not available for management of left main coronary artery (LMCA) compression syndrome, percutaneous coronary intervention and stent implantation remain a feasible option for the treatment, specifically for patients with a high surgical risk. Treatment of pulmonary vein or artery compression is more varied and determined by etiology. This review article is focused on detailed discussion of extrinsic compression of coronary arteries, mainly the LMCA and brief discussion on pulmonary vasculature compression by surrounding anatomical and pathological entities, with focus on pathophysiology, clinical features, complications and role of imaging in its diagnosis and management.

Ventilation-Perfusion Scan: A Primer for Practicing Radiologists

Lung scintigraphy, or ventilation-perfusion (V/Q) scan, is one of the commonly performed studies in nuclear medicine. Owing to variability in clinical applications and different departmental workflows, many trainees are not comfortable interpreting the results of this study. This article provides a simplified overview of V/Q imaging, including a review of its technique, interpretation methods, and established and emerging clinical applications. The authors review the role of V/Q imaging in evaluation of acute and chronic pulmonary embolism, including the role of SPECT/CT and comparing V/Q scan with CT angiography. In addition, a variety of other applications of pulmonary scintigraphy are discussed, including congenital heart disease, pretreatment planning for lung cancer and emphysema, posttransplant imaging for bronchiolitis obliterans, and less common vascular and nonvascular pathologic conditions that may be detected with V/Q scan. This article will help radiologists and residents interpret the results of V/Q scans and understand the various potential clinical applications of this study. Online supplemental material is available for this article. ^©RSNA, 2021.

COVID-19 as a cause of chronic pulmonary hypertension: pathophysiological rationale and potential of instrumental investigations

Coronavirus disease 2019 (COVID-19) is a poorly understood and dangerous medical problem. COVID-19-related pulmonary vessels involvement is a complex set of interrelated pathophysiological processes associated with vascular endothelial dysfunction and accompanied by thrombosis of various localization, vasomotor disorders, severe respiratory failure, as well as pulmonary embolism (PE) resulting in chronic thromboembolic pulmonary hypertension (CTEPH). According to computed tomographic pulmonary angiography, the incidence of PE in patients with COVID-19 ranges from 23 to 30%. The aim of this work was to focus the doctors' attention on the risk of pulmonary hypertension in patients after COVID-19.

Despite the ability of severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) to infect various organs and systems, the main and most serious complications are pulmonary infiltration, acute respiratory distress syndrome, acute respiratory failure and PE, which in some cases becomes the triggering mechanism for CTEPH development. The literature review presents data on main pathological abnormalities developing in target organs during COVID-19 and playing an important role in increasing the CTEPH risk. The paper describes the main methods of instrumental investigations of CTEPH and an algorithm for its use in COVID-19 survivors.

The revealed data demonstrated that the absence of obvious signs of pulmonary hypertension/CTEPH, the cardiopulmonary system abnormalities cannot be ruled out. Therefore, it seems appropriate to actively follow up COVID-19 survivors. A thoroughly, purposefully collected anamnesis, pulmonary function tests and stress echocardiography in an ambiguous clinical situation will play a leading role as they identify cardiopulmonary disorders and provide the doctor with basic information for further planning of patient management.

Idiopathic fibrous mediastinitis with refractory pleural effusion: a case report and literature review

Fibrous mediastinitis is a rare progressive disease characterized by invasive proliferation of fibrous tissue in the mediastinum. This tissue proliferation leads to compression of the mediastinal structures in the thoracic cavity, including the pulmonary vessels, esophagus, and trachea, causing corresponding symptoms and complications such as pulmonary hypertension. In clinical practice, the diagnosis of fibrous mediastinitis is often delayed or missed because of the rarity and variable clinical manifestations of this condition. This article presents a case of idiopathic fibrous mediastinitis that manifested as pleural effusion of unknown etiology along with a review of the relevant literature.

The combined prevalence of classified rare rheumatic diseases is almost double that of ankylosing spondylitis

BACKGROUND

Rare diseases (RDs) affect less than 5/10,000 people in Europe and fewer than 200,000 individuals in the United States. In rheumatology, RDs are heterogeneous and lack systemic classification. Clinical courses involve a variety of diverse symptoms, and patients may be misdiagnosed and not receive appropriate treatment. The objective of this study was to identify and classify some of the most important RDs in rheumatology. We also attempted to determine their combined prevalence to more precisely define this area of rheumatology and increase awareness of RDs in healthcare systems. We conducted a comprehensive literature search and analyzed each disease for the specified criteria, such as clinical symptoms, treatment regimens, prognoses, and point prevalences. If no epidemiological data were available, we estimated the prevalence as 1/1,000,000. The total point prevalence for all RDs in rheumatology was estimated as the sum of the individually determined prevalences.

RESULTS

A total of 76 syndromes and diseases were identified, including vasculitis/vasculopathy (n = 15), arthritis/arthropathy (n = 11), autoinflammatory syndromes (n = 11), myositis (n = 9), bone disorders (n = 11), connective tissue diseases (n = 8), overgrowth syndromes (n = 3), and others (n = 8). Out of the 76 diseases, 61 (80%) are classified as chronic, with a remitting-relapsing course in 27 cases (35%) upon adequate treatment. Another 34 (45%) diseases were predominantly progressive and difficult to control. Corticosteroids are a therapeutic option in 49 (64%) syndromes. Mortality is variable and could not be determined precisely. Epidemiological studies and prevalence data were available for 33 syndromes and diseases. For an additional eight diseases, only incidence data were accessible. The summed prevalence of all RDs was 28.8/10,000.

CONCLUSIONS

RDs in rheumatology are frequently chronic, progressive, and present variable symptoms. Treatment options are often restricted to corticosteroids, presumably because of the scarcity of randomized controlled trials. The estimated combined prevalence is significant and almost double that of ankylosing spondylitis (18/10,000). Thus, healthcare systems should assign RDs similar importance as any other common disease in rheumatology.

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.

Thoracic Endemic Fungi in the United States: Importance of Patient Location

The digitization of radiographic studies along with high-speed transmission of images has formed the basis of teleradiology, which has become an integral component in the workflow of a contemporary radiology practice. It is with this advent and growing utilization of teleradiology that the significance of the source location of images has gained importance. Specifically, the importance of where the patient resides and what endemic fungi occur in that location cannot be underestimated. In the United States, histoplasmosis, coccidioidomycosis, blastomycosis, and cryptococcosis are caused by endemic fungi occurring in the Ohio and Mississippi river valleys, the Southwest, the Upper Midwest, and the Pacific Northwest, respectively. All of these organisms enter the body through the respiratory system and have the potential to cause significant morbidity and mortality. Patients infected with these fungi are often asymptomatic but may present with acute flulike symptoms such as fever, cough, or dyspnea. Patients may also present with vague chronic symptoms including cough, fever, malaise, and weight loss. Thoracic manifestations at radiography and CT include consolidation, nodules, cavities, lymphadenopathy, and pleural disease. PET may show fluorine 18-fluorodeoxyglucose uptake with active acute or chronic infections, and it is difficult to distinguish infections from malignancy. Imaging findings may be nonspecific and can be confused with other disease processes, including malignancy. The patient demographics, clinical history, and location are clues that may lead to a proper diagnosis of endemic fungal disease. The radiologist should be cognizant of the patient location to provide a correct and timely radiologic diagnosis that helps guide the clinician to initiate appropriate therapy. ^©RSNA, 2021.

A young immunocompetent female with anterior mediastinal mass

A 23-year-old female presented with 3 months of central chest pain and fever. Clinico-radiological investigations were consistent with an anterior mediastinal mass. This clinicopathologic conference discusses the differential diagnoses of such a presentation and their management options.

An unusual pediatric case of tuberculosis-associated mediastinal fibrosis with concomitant pulmonary arterial and venous occlusion

We present a case of a 4-year-old boy with tuberculosis-associated mediastinal fibrosis with concomitant pulmonary arterial and venous occlusion, highlighting the role computed tomography angiography in identification of the disease process, coexistent vascular abnormalities and associated complications.

Evaluation of Outcomes Following Pulmonary Artery Stenting in Fibrosing Mediastinitis

PURPOSE

Fibrosing mediastinitis is a rare disease characterized by fibrosis of mediastinal structures with subsequent constriction of the bronchi and pulmonary vessels leading to potential respiratory compromise and death. Presently, there is no effective curative treatment with available treatments focused on reducing symptomology, including placement of pulmonary artery stents. Limited studies examine the use of stents in fibrosing mediastinitis. Given this knowledge gap, we assessed stent patency, hemodynamics, complications, and secondary outcomes of clinical improvement of pulmonary artery stenting for fibrosing mediastinitis.

MATERIALS AND METHODS

Nine patients with fibrosing mediastinitis and pulmonary artery stents were retrospectively identified for inclusion (six females, three males; mean age 44.17 years, range 13-68; total 13 primary stents) from 2005 to 2018. Eight patients had history of PH. All patients had dyspnea on presentation. Seven patients had ventilation/perfusion studies demonstrating impairment. Results from computed tomography and echocardiography studies were collected to assess patency and physiologic response.

RESULTS

All patients received initial angioplasty and stenting of the right pulmonary artery (10 stents). Two patients underwent additional left-sided intervention (3 stents). Stenting significantly increased lesion luminal patency (54-79%; P < 0.005) and reduced systolic pressure gradients across stenoses (mean -9.38 mmHg; P < 0.005). Primary patency at one year was 90%. Two stents received reintervention at 276 and 497 days. 89% reported improvement in dyspnea in the initial post-stenting period. There were no mortalities or major complications.

CONCLUSION

Pulmonary artery stenting improves vascular patency and provides symptomatic relief in patients with fibrosing mediastinitis.

A Rare Case of Bronchomediastinal Pulmonary Vein Fistula due to Fibrosing Mediastinitis

Fibrosing mediastinitis (FM) is a rare condition with extensive proliferation of fibrous tissue in the mediastinum usually happens few years after Histoplasma infection. FM usually occurs years later after presentation of Histoplasma infection, and usually what makes patients seek medical attention are symptoms from compression and occlusion of vital mediastinal structures, such as the central airways, superior vena cava, pulmonary arteries, and veins. Rarely, heart, pericardium, coronaries, and aorta are involved. We report a case of 39-year-old-male who was admitted with fever and cough. The patient’s condition worsened despite being on broad-spectrum antibiotics, with worsening encephalopathy and a new onset lower extremity weakness. Brain imaging showed multiple strokes suggestive of embolic event. CT chest/abdomen was suggestive of FM along with cavitary lung nodules and pneumomediastinum. Splenic and renal infarcts were also noted. Infective endocarditis was one of the top differential diagnosis due to multiple embolic infarcts, and hence a transesophageal echocardiography (TEE) was pursued. TEE showed a mass along with air bubbles entering the left atrium from the pulmonary vein. On re-evaluation of CT chest images, a fistula was seen extending from the mediastinum to the left main bronchus and the left upper pulmonary vein. This supported the diagnosis of FM with erosion of lymph node into the left main bronchus and left upper pulmonary artery, leading to fistula formation and subsequent systemic air embolization. The diagnosis of FM requires a multimodality approach, high clinical suspicion, and accurate history taking. Treatment mainly aims at managing the mechanical complications.

Benign lesions of the mediastinum: A review with emphasis on cytology and small biopsy specimens

This review focuses on the diagnosis of select benign processes, ranging from reactive entities to heterotopic tissues to neoplasms, which may occur in the mediastinum. Currently, the mediastinum can be evaluated and biopsied with endoscopic procedures. Therefore, cytopathology specimens, fine needle aspirations, and small biopsies play an important role in the diagnosis of these lesions. In this review, an emphasis is given to relevant clinical presentations, histologic and cytologic findings, differential diagnoses, ancillary testing, and interpretation. Pitfalls are reviewed and discussed in each section. It is important for both surgical pathologists and cytopathologists to be familiar with these entities and their cytologic and histologic features that may be helpful in reaching a diagnosis.

Diagnosis of an unusual case of idiopathic mediastinal fibrosis by 18F-FDG PET/CT

Diagnosis of idiopathic mediastinal fibrosis was done by exclusion in a 54-year-old woman with dyspnoea, chest pain, cough and fatigue showing positivity of 2-deoxy-2-[¹⁸F]fluoro-D-glucose positron-emission tomography/computed tomography total body imaging which turned out to normal after six and eighteen months of prednisone and pirfernidone treatment.

Mimickers of chronic thromboembolic pulmonary hypertension on imaging tests: a review

Chronic thromboembolic pulmonary hypertension (CTEPH) is caused by mechanical obstruction of large pulmonary arteries secondary to one or more episodes of pulmonary embolism. Ventilation perfusion scan is the recommended initial screening test for this condition and typically shows multiple large mismatched perfusion defects. However, not all patients with an abnormal ventilation perfusion scan have CTEPH since there are other conditions that be associated with a positive ventilation perfusion scan. These conditions include in situ thrombosis, pulmonary artery sarcoma, fibrosing mediastinitis, pulmonary vasculitis and sarcoidosis, among others. Although these conditions cannot be distinguished from CTEPH using a ventilation perfusion scan, they have certain characteristic radiological features that can be demonstrated on other imaging techniques such as computed tomography scan and can help in differentiation of these conditions. In this review, we have summarized some key clinical and radiological features that can help differentiate CTEPH from the CTEPH mimics.

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.

Non-aortic vascular findings on chest CT angiogram: including arch vessels and bronchial arteries

CT angiogram (CTA) has become the modality of choice for imaging of thoracic vascular pathologies, involving the aorta and the pulmonary arteries. Apart from showing exquisite details of these large arteries, pathologies and anatomic variants of their branches can also be studied to a great extent. The major branches of aortic arch can be affected by a wide variety of pathologies ranging from atherosclerosis to trauma and vasculitis. Bronchial arteries in spite of supplying only 1% of lung parenchyma can become hypertrophied in various congenital and acquired conditions, becoming an important source of collateral circulation as well as a source for life threatening hemoptysis. CT also plays an important role in diagnosis of vascular compression at the thoracic outlet. With advances in CT technology, the acquisition, interpretation and clinical applications of CT angiography will continue to grow in the years to come.

CTPA, DECT, MRI, V/Q Scan, and SPECT/CT V/Q for the noninvasive diagnosis of chronic thromboembolic pulmonary hypertension: A protocol for systemic review and network meta-analysis of diagnostic test accuracy

BACKGROUND

To determine the diagnostic accuracy of techniques with chronic thromboembolic pulmonary hypertension (CTEPH) patients via a protocol for systemic review and network meta-analysis.

METHODS

We will search PubMed, EMBASE, Web of Science, and Google Scholar from inception to October 1, 2018. The reference lists of the retrieved articles are also consulted. Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) will be used to assess the risk of bias in each study. The direct meta-analyses, network meta-analyses, and ranking of competing diagnostic tests will be used by STATA 12.0 and WINBUGS 1.4. Heterogeneity and inconsistency are assessed.

RESULTS

This study is ongoing, will be submitted to a peer-reviewed journal publication once completed.

CONCLUSION

This study will provide a comprehensive evidence summary of diagnostic test accuracy in detecting the CTEPH, and can help patients and clinicians to select appropriate or best diagnostic test.

ETHICS AND COMMUNICATION

No ethical approval and patient consent are required, because it is based on published researches.

PROSPERO REGISTRATION NUMBER

CRD42019121279.

Fibrosing/Sclerosing Lesions of the Mediastinum: A Review

Fibrosing lesions of the mediastinum represent a small but challenging group of lesions that range in etiology from infectious to idiopathic to neoplastic. The diagnosis of such lesions becomes more challenging in the setting of mediastinoscopic biopsies. In addition, over the years, there has been further accumulation of knowledge of the clinical aspects of these lesions that needs to be incorporated into their evaluation. Therefore, it is essential that in the general evaluation of these fibrosing processes, one not only carefully examines the histopathologic features of the lesion, that of a fibroinflammatory process with the appropriate histochemical and immunohistochemical studies, but also carefully evaluates the clinical presentation and imaging findings. Needless to say, as will be illustrated in this review, determining a definitive unequivocal diagnosis on a small mediastinoscopic biopsy may be difficult, and often one needs to provide guidance on the perspective of the histologic features present. In some cases, mainly tumoral conditions with extensive fibrosis, a conclusive diagnosis can be made; however, it is those cases in which the extensive fibrosis is the only histopathologic feature where more appropriate guidance is required. While this review will focus more on the non-neoplastic fibroinflammatory lesions of the mediastinum, within the discussion of differential diagnoses, we will discuss some neoplastic conditions that commonly show extensive fibrosing features.

Many Faces of Thoracic Histoplasmosis-Pictorial Essay

Histoplasmosis is primarily a pulmonary fungal infection with a vast array of radiological manifestations, which can mimic a number of thoracic diseases. This article reviews various presentations of histoplasmosis on chest imaging.

Imaging of Pulmonary Hypertension: Pictorial Essay

Pulmonary hypertension (PH) is an end result of a diverse array of complex clinical conditions that invoke hemodynamic and pathophysiological changes in the pulmonary vasculature. Many patients' symptoms begin with dyspnea on exertion for which screening tests such as chest roentgenograms and more definitive noninvasive tests such as CT scans are ordered initially. It is imperative that clinicians are cognizant of subtle clues on these imaging modalities that alert them to the possibility of PH. These clues may serve as a stepping stone towards more advanced noninvasive (echocardiogram) and invasive (right heart catheterization) testing. On the CT scan, the signs are classified into mediastinal and lung parenchymal abnormalities. In addition to suspecting the diagnosis of PH, this paper provides a pictorial essay to guide health care professionals in identifying the etiology of PH. This paper also provides concrete definitions, wherever possible, of what constitutes abnormalities in PH, such as dilated pulmonary arteries, pruning of vessels, and increased thickness of free wall of the right ventricle. The sensitivities and specificities of each sign are enumerated. The common radiographic and clinical features of many different etiologies of PH are tabulated for the convenience of the readers. Some newer imaging modalities such as dual-energy CT of the chest that hold promise for the future are also described.

Multimodality Imaging of Focal and Diffuse Fibrosing Mediastinitis

Fibrosing mediastinitis is a rare benign but potentially life-threatening process that occurs because of proliferation of fibrotic tissue in the mediastinum. The focal subtype is more common and typically is associated with an abnormal immunologic response to Histoplasma capsulatum infection. Affected patients are typically young at presentation, but a wide age range has been reported, without a predilection for either sex. The diffuse form may be idiopathic or associated with autoimmunity, usually affects middle-aged and/or elderly patients, and is more common in men. For both subtypes, patients present with signs and symptoms related to obstruction or compression of vital mediastinal structures. The most common presenting signs and symptoms are cough, dyspnea, recurrent pneumonia, hemoptysis, and pleuritic chest pain. Patients with the diffuse subtype may have additional extrathoracic symptoms depending on the other organ systems involved. Because symptom severity is variable, treatment should be individualized with therapies tailored to alleviate compression of the affected mediastinal structures. Characteristic imaging features of fibrosing mediastinitis include infiltrative mediastinal soft tissue (with or without calcification) with compression or obstruction of mediastinal vascular structures and/or the aerodigestive tract. When identified in the appropriate clinical setting, these characteristic features allow the radiologist to suggest the diagnosis of fibrosing mediastinitis. Careful assessment is crucial at initial and follow-up imaging for exclusion of underlying malignancy, assessment of disease progression, identification of complications, and evaluation of treatment response. Online supplemental material is available for this article. ^©RSNA, 2019.

Sclerosing Mediastinitis Causing Unilateral Pulmonary Edema Due to Left Atrial and Pulmonary Venous Compression. A Case Report and Literature Review

Sclerosing mediastinitis (SM), previously named chronic fibrosing mediastinitis, is an inflammatory process that in its end-stage results to sclerosis around the mediastinal structures. SM is quite rare and has been correlated with inflammatory and autoimmune diseases, as well as malignancy. SM may either present in a mild form, with minor symptoms and a benign course or in a more aggressive form with severe pulmonary hypertension and subsequent higher morbidity and mortality. The diagnosis of SM may be difficult and quite challenging, as symptoms depend on the mediastinal structure that is mainly involved; quite often the superior vena cava. However, practically any mediastinal structure may be involved by the fibrotic process, such as the central airways, as well as the pulmonary arteries and veins, leading to obstruction or total occlusion. The latter may be impossible to undergo proper surgical excision of the lesion, and is considered to be a real challenge to the surgeon. We herein report a case of SM that presented with arterial and venous compression. The imaging appearance was that of unilateral pulmonary edema, associated with lung collapse. The case is supplemented by a non-systematic review of the relevant literature.

Aggressive and progressive fibrosing mediastinitis involving the thoracic spine mimicking malignancy: A case report

Fibrosing mediastinitis is an uncommon benign disorder in which a chronic inflammatory reaction results in diffuse fibrosis of the mediastinum, potentially compromising the airways, great vessels and other mediastinal structures. Herein we describe a progressive course of fibrosing mediastinitis in a 72-year-old man. Computed tomography images depicted a diffuse, infiltrative, soft tissue mass involving the esophagus and superior vena cava in the mediastinum. Magnetic resonance imaging revealed destruction of the adjacent thoracic spine. Positron emission tomography-computed tomography also revealed increased metabolism in the periphery of the mass.

Proximal Interruption of the Pulmonary Artery

Proximal interruption of the pulmonary artery (PIPA) is an uncommon developmental anomaly resulting in underdevelopment of the proximal portion of the pulmonary artery with preservation of the intrapulmonary segments. Clinical presentation ranges between an asymptomatic incidental finding to massive hemoptysis. When findings suggestive of PIPA are present radiographically, the diagnosis of PIPA can be definitively diagnosed with computed tomography or magnetic resonance pulmonary angiography. Other imaging modalities, such as nuclear perfusion scan and catheter angiography can help in the diagnosis.

Pictorial review of the pulmonary vasculature: from arteries to veins

Pathology of the pulmonary vasculature involves an impressive array of both congenital and acquired conditions. While some of these disorders are benign, disruption of the pulmonary vasculature is often incompatible with life, making these conditions critical to identify on imaging. Many reviews of pulmonary vascular pathology approach the pulmonary arteries, pulmonary veins and bronchial arteries as individual topics. The goal of this review is to provide an integrated overview of the high-yield features of all major disorders of the pulmonary vasculature. This approach provides a more cohesive and comprehensive conceptualisation of respiratory pathology. In this review, we present both the salient clinical and imaging features of congenital and acquired disorders of the pulmonary vasculature, to assist the radiologist in identifying pathology and forming a robust differential diagnosis tailored to the presenting patient. TEACHING POINTS: • Abnormalities of the pulmonary vasculature are both congenital and acquired. • Pathology of a single pulmonary vascular territory often affects the entire pulmonary vasculature. • Anomalous pulmonary venous flow is named as a function of its location and severity. • Bronchial arteries often undergo dilatation secondary to cardio-respiratory pathology.

Fibrosing Mediastiniti: a Rare Cause of Unilateral Absent Lung Perfusion on a V/Q Scan

We report a case of a 29-year-old female with a history of asthma, post-partum ARDS, and pulmonary hypertension who presents with severe shortness of breath. The patient describes her shortness of breath as progressive over the past 10 years. Chest radiography and CT angiography of the thorax showed findings consistent with fibrosing mediastinitis with severe stenosis of the left main pulmonary artery. This resulted in appearance of unilateral absent left lung perfusion on quantitative Tc-99-MAA perfusion and Xe-133 ventilation (V/Q) scan.

Tomographic assessment of thoracic fungal diseases: a pattern and signs approach

Pulmonary fungal infections, which can be opportunistic or endemic, lead to considerable morbidity and mortality. Such infections have multiple clinical presentations and imaging patterns, overlapping with those of various other diseases, complicating the diagnostic approach. Given the immensity of Brazil, knowledge of the epidemiological context of pulmonary fungal infections in the various regions of the country is paramount when considering their differential diagnoses. In addition, defining the patient immunological status will facilitate the identification of opportunistic infections, such as those occurring in patients with AIDS or febrile neutropenia. Histoplasmosis, coccidioidomycosis, and paracoccidioidomycosis usually affect immunocompetent patients, whereas aspergillosis, candidiasis, cryptococcosis, and pneumocystosis tend to affect those who are immunocompromised. Ground-glass opacities, nodules, consolidations, a miliary pattern, cavitary lesions, the halo sign/reversed halo sign, and bronchiectasis are typical imaging patterns in the lungs and will be described individually, as will less common lesions such as pleural effusion, mediastinal lesions, pleural effusion, and chest wall involvement. Interpreting such tomographic patterns/signs on computed tomography scans together with the patient immunological status and epidemiological context can facilitate the differential diagnosis by narrowing the options.

Mediastinal and retroperitoneal fibrosis as a manifestation of breast cancer metastasis: A case report and literature review

RATIONALE

Mediastinal and retroperitoneal fibrosis as a manifestation of metastasis from malignancies is rare disease and particularly, cases of mediastinal fibrosis have been rarely reported.

PATIENT CONCERNS

A 60-year-old woman presented with dyspnea and bilateral flank pain. The patient had no previous history of malignancy.

DIAGNOSES

A contrast-enhanced chest computed tomography scan revealed a left breast mass and infiltrative soft tissue masses in the mediastinum and retroperitoneum, which showed high fluorodeoxyglucose uptake on positron emission tomography scan. The left breast mass was proven as a malignancy on biopsy and surgical excisional biopsy of the mediastinal mass revealed metastasis from the breast cancer on histopathologic examination.

INTERVENTIONS

Our patient was treated with palliative hormone therapy for the primary breast cancer and metastasis with mediastinal and retroperitoneal fibrosis.

OUTCOMES

Follow-up imaging studies showed improvement of the primary breast cancer and also metastasis.

LESSONS

We report this rare case to emphasize that mediastinal and retroperitoneal fibrosis can be a presentation of metastasis from various primary malignancies. We expect that appropriate diagnosis and treatment for metastatic mediastinal and retroperitoneal fibrosis can have a beneficial effect on disease course and prognosis of the patient.

IgG4-related Disease in Thymus. A Very Rare Case of Chronic Fibrosis Mimicking Sarcoidosis

IgG4-related disease (IgG4-RD) is a multi-organ immune-mediated chronic fibroinflammatory condition, with unclear certain etiology. It is morphologically characterized by storiform fibrosis, dense IgG4-positive lympho-plasmacytic infiltrate, and obliterative phlebitis. It was recognized as a systemic condition as recently as 2003. IgG4-RD has been described in virtually every organ, forming sclerosing masses, and often mimicking tumors. Clinically, patients present unspecific symptoms and this condition is often recognized incidentally. The epidemiology remains poorly studied, but it has been noted that in the majority of recorded instances, patients are middle-aged men. IgG4-RD could mimic conditions other than tumors, such as infection, inflammation, or other systemic disorders. To ensure accuracy of diagnosis, an exhaustive histopathological analysis is required, together with clinical, radiological, and serological data. Thymic fibrosis in the absence of other primary thymic lesions is a very rare occurrence; in English literature only 1 case has been reported with scattered IgG4 plasma cells infiltrate and focal obliterative phlebitis. We will describe, for the first time, the case of a 49-year-old man displaying an anterior mediastinic, hilar, and intramyocardial mass simulating a sarcoidosis, with a definitive diagnosis of IgG4-related thymic fibrosis extending to the mediastinum and the heart. At the histological examination, we found many features of IgG4-RD in the thymic tissue, such as diffused storiform fibrosis, dense lymphoplasmacytic infiltrate with abundant plasma cells IgG4 positive (ratio IgG/IgG4: 40%), obliterative phlebitis, eosinophilic infiltrate, and Castleman-like lymphoid follicles. We discussed the differential diagnosis and reviewed the literature and the other cases of IgG4-related diseases that had been diagnosed in our department.