(BQ) Part 2 book Diagnostic imaging chest presents the following contents: Connective tissue disorders, immunological diseases and vasculitis, mediastinal abnormalities, cardiovascular disorders, trauma, post treatment chest, pleural diseases, chest wall and diaphragm.
Diagnostic Imaging Chest Treatment Discontinuation of use of lipoid agent Diagnosis Transthoracic needle biopsy may be diagnostic DIAGNOSTIC CHECKLIST Consider Lipoid pneumonia in patients with pulmonary nodule, mass, or consolidation with intrinsic fat attenuation or “crazy-paving” pattern on CT SELECTED REFERENCES Betancourt SL et al: Lipoid pneumonia: spectrum of clinical and radiologic manifestations AJR Am J Roentgenol 194(1):103-9, 2010 Franquet T et al: The crazy-paving pattern in exogenous lipoid pneumonia: CT-pathologic correlation AJR Am J Roentgenol 170(2):315-7, 1998 Section - Connective Tissue Disorders, Immunological Diseases, and Vasculitis Introduction and Overview Approach to Connective Tissue Disorders, Immunological Diseases, and Vasculitis > Table of Contents > Section - Connective Tissue Disorders, Immunological Diseases, and Vasculitis > Introduction and Overview > Approach to Connective Tissue Disorders, Immunological Diseases, and Vasculitis Approach to Connective Tissue Disorders, Immunological Diseases, and Vasculitis Gerald F Abbott, MD Imaging Modalities For patients with connective tissue disorders, immunological diseases, and vasculitis who have symptoms referable to the thorax, the imaging evaluation typically begins with chest radiography but often requires CT/HRCT studies for accurate detection and characterization of pleuropulmonary abnormalities In some cases, the pleuropulmonary imaging findings of these disorders are the initial manifestation of the disease, which may not become clinically apparent until months or years later Connective Tissue Disease Connective tissue diseases (also called collagen vascular diseases) comprise a group of autoimmune disorders characterized by damage to connective tissue components at various anatomic locations in the body These include rheumatoid arthritis, scleroderma, mixed connective tissue disorder, polymyositis and dermatomyositis, systemic lupus erythematosus, Sjögren syndrome, and ankylosing spondylitis These disease processes may be associated with focal or diffuse pulmonary abnormalities Diffuse infiltrative pulmonary disease is most commonly detected in patients with rheumatoid arthritis and in those with progressive systemic sclerosis (scleroderma) The majority of connective tissue diseases have the potential to produce a chronic interstitial lung disease that is indistinguishable from usual interstitial pneumonia (UIP) in its clinical, radiographic, and CT/HRCT manifestations However, ground-glass opacity is often a predominant CT/HRCT finding in patients with lung disease associated with connective tissue disorders, typically with finer reticulation and less frequent honeycombing than that which characterizes UIP and idiopathic pulmonary fibrosis (IPF) Connective tissue diseases are often associated with pathologic abnormalities other than UIP, including nonspecific interstitial pneumonia (NSIP), bronchiolitis obliterans, bronchiectasis, lymphoid interstitial pneumonia (LIP), and cryptogenic organizing pneumonia (COP) Because patients with connective tissue disease are at risk for the development of interstitial lung disease, which may progress to end-stage fibrosis and honeycomb lung, they are also at increased risk for the development of primary lung cancer Thus, radiologists must regard any new pulmonary nodule or mass in such patients with a high index of suspicion for malignancy and should aggressively pursue a definitive diagnosis in these cases Immunocompromised Patients In recent decades, several factors have led to an increased number of immunocompromised patients, including the widespread use of ablative chemotherapy in the management of patients with cancer, an increase in the frequency of solid organ and bone marrow transplantation, and the epidemic of HIV infection Detection of pleuropulmonary imaging abnormalities in immunocompromised patients should always prompt consideration of infection as an important differential diagnostic possibility However, many other disease processes that mimic infection must also be 778 Diagnostic Imaging Chest excluded, including cytotoxic and noncytotoxic drug reactions, interstitial lung diseases, lymphoproliferative disorders, and malignant neoplasms The chest radiograph is an important initial imaging modality in the evaluation of symptomatic immunocompromised patients, but it may be normal in 10% of patients with pulmonary complications Chest CT and HRCT provide improved accuracy in the demonstration of imaging abnormalities, their patterns, distribution, and the extent of pulmonary involvement When combined with clinical and epidemiological information, imaging findings may help to narrow the differential diagnostic possibilities and determine the next best steps in the diagnostic process Comparison with previous chest imaging studies is critical to recognize new abnormalities and determine the temporal sequence of their progression The presence or absence of associated findings such as lymphadenopathy and pleural effusion may help to narrow the list of differential diagnostic possibilities Specific clinical and imaging features may be important clues to the diagnosis For example, lung nodules, masses, and consolidations detected by CT or HRCT in association with neutropenia should prompt consideration of invasive aspergillosis as a leading diagnostic possibility In fact, management decisions in the treatment of opportunistic infections in immunocompromised patients are frequently made based on imaging abnormalities and may not require microbiologic confirmation On the other hand, the finding of ground-glass opacity in patients with HIV/AIDS is highly suggestive of Pneumocystis jiroveci pneumonia (PCP) Pulmonary Hemorrhage and Vasculitis Pulmonary vasculitis syndromes include several disease entities, some of which frequently affect the lung (e.g., Wegener granulomatosis, Churg-Strauss vasculitis, and microscopic polyangiitis) Pulmonary vasculitis also occurs in miscellaneous systemic disorders, in diffuse pulmonary hemorrhagic syndromes, and in other secondary, localized forms The pulmonary vasculitis syndromes are clinicopathologic entities; their diagnosis is based not solely on pathologic findings, but rather on a correlation among clinical, imaging, and pathologic features Clinical settings in which pulmonary vasculitis may occur are variable and include diffuse pulmonary hemorrhage, pulmonary renal syndromes, pulmonary nodular and/or cavitary disease, and upper airway lesions When patients present with pulmonary hemorrhage, corroborated by imaging findings and clinical testing, pulmonary vasculitis should be considered as a differential diagnostic possibility, including the most common vasculitis syndrome, Wegener granulomatosis The diagnosis of idiopathic pulmonary hemorrhage is always a diagnosis of exclusion Selected References Hansell DM et al: Idiopathic interstitial pneumonias and immunologic disease of the lungs In Imaging of Diseases of the Chest St Louis: Mosby 608-39, 2010 P.7:3 Image Gallery (Left) HRCT of a patient with scleroderma shows esophageal dilatation and posterior subpleural ground-glass and reticular opacities Connective tissue diseases may exhibit findings indistinguishable from UIP However, ground-glass opacity is typically the predominant finding in patients with associated NSIP (Right) HRCT of a patient with scleroderma shows pulmonary fibrosis and honeycombing A focal nodular lesion represents associated primary lung cancer 779 Diagnostic Imaging Chest (Left) CECT of a patient with lupus pneumonitis demonstrates patchy ground-glass opacities that involved both lungs The CT imaging differential diagnosis of ground-glass opacity in patients with lupus also includes pneumonia and pulmonary hemorrhage (Right) CECT of a patient with systemic lupus erythematosus shows bibasilar subpleural reticular opacities, traction bronchiectasis, and early honeycombing Patients with lupus may exhibit CT manifestations of usual interstitial pneumonia (Left) CECT of a patient with polymyositis shows findings of nonspecific interstitial pneumonia with subpleural reticular and ground-glass opacities Note the relative sparing of the subpleural lung , a CT finding that is very suggestive of NSIP (Right) CECT of a patient with idiopathic pulmonary hemorrhage (IPH) shows bilateral multifocal ground-glass opacities Approximately 25% of patients with IPH will subsequently develop an autoimmune disorder Immunological and Connective Tissue Disorders Ovid: Diagnostic Imaging: Chest > Table of Contents > Section - Connective Tissue Disorders, Immunological Diseases, and Vasculitis > Immunological and Connective Tissue Disorders > Rheumatoid Arthritis Jonathan H Chung, MD Key Facts Terminology Rheumatoid arthritis (RA) 780 Diagnostic Imaging Chest Subacute or chronic inflammatory polyarthropathy of unknown cause Imaging Radiographs Pleural thickening &/or effusion Reticulonodular & irregular linear opacities, lower lung zones Rheumatoid nodules (< 5%) CT/HRCT Evaluation of pleural effusions & thickening Interstitial fibrosis (30-40%): Usual interstitial pneumonia & nonspecific interstitial pneumonia Nodules or masses Bronchiectasis, bronchial wall thickening, constrictive bronchiolitis Top Differential Diagnoses Idiopathic pulmonary fibrosis (IPF) Scleroderma Cryptogenic organizing pneumonia (COP) Asbestosis Clinical Issues Involves synovial membranes & articular structures Extraarticular RA: More common in men Thoracic RA: Dyspnea, cough, pleuritic pain May be asymptomatic 5-year survival 40%: Infection most common cause of death Diagnostic Checklist Consider RA-related lung disease in patient with lung fibrosis & history of RA or polyarthritis (especially distal clavicular resorption) (Left) Sagittal HRCT of a patient with RA shows basilar and peripheral predominant pulmonary fibrosis with honeycombing , traction bronchiectasis , reticulation, and mild ground-glass opacity, suggestive of usual interstitial pneumonia pattern of disease (Right) Coronal HRCT of a patient with RA shows mild peripheral subpleural mixed ground-glass and reticular opacities diagnosed as NSIP on lung biopsy In cases of mild lung fibrosis, tissue sampling is often required for definitive diagnosis 781 Diagnostic Imaging Chest (Left) Axial CECT of a patient with RA shows a small right pleural effusion and peripheral right lung nodules (Right) Coronal CECT of a middle-aged man with RA shows a right middle lobe nodule , consistent with a rheumatoid nodule Note the small right pleural effusion Thoracic manifestations of RA are much more common in men than in women, although RA is more common in women overall P.7:5 TERMINOLOGY Abbreviations Rheumatoid arthritis (RA) Definitions Subacute or chronic inflammatory polyarthropathy of unknown cause Associated thoracic findings: Pleural disease, interstitial fibrosis, lung nodules, airway disease Complications: Pneumonia, empyema, drug reaction, amyloidosis, cor pulmonale IMAGING General Features Best diagnostic clue Interstitial lung disease in patient with polyarthritis (especially distal clavicular resorption) Location Interstitial lung disease: Lower lobes Radiographic Findings Pleural disease Pleural thickening (20%) Pleural effusion Much more common in men Small to large, usually unilateral, may be bilateral Transient, persistent, or relapsing Susceptibility to empyema Pneumothorax: Rare Associated with rheumatoid nodules Parenchymal disease Reticulonodular & irregular linear opacities with lower lung zone predominance Interstitial fibrosis in 5% on chest radiography Progressive lower lobe volume loss Rheumatoid nodules (< 5%) Solitary or multiple, mm to cm Peripheral (subpleural) Waxing & waning course May cavitate (50%), thick smooth wall More common in men, especially smokers Caplan syndrome: Very rare 782 Diagnostic Imaging Chest Multiple lung nodules in coal miners with RA Large rounded nodules (0.5-5 cm) Nodules exhibit peripheral distribution Airway disease Hyperinflation Diffuse reticulonodular opacities: Follicular bronchiolitis Bronchiectasis (20%) Isolated or related to traction bronchiectasis Pulmonary micronodules CT Findings HRCT Abnormal in 50%, more sensitive than pulmonary function tests (PFTs) Pleural disease: Common abnormality in RA Pleural effusion Moderate size; often subacute or chronic Often loculated Pleural thickening Fibrothorax Rounded atelectasis May be associated with pericarditis, interstitial fibrosis, interstitial pneumonia, &/or lung nodules Rheumatoid lung disease Much more common in men Interstitial fibrosis in 30-40% by HRCT Typically usual interstitial pneumonia (UIP) & nonspecific interstitial pneumonia (NSIP) UIP: Subpleural & basilar predominant reticulation, traction bronchiolectasis, & honeycomb lung NSIP: Basilar predominant ground-glass opacity & reticulation; may spare subpleural lung Cryptogenic organizing pneumonia (COP): Less common Peripheral or central consolidation & ground-glass opacities; may be mass-like or nodular Nodules or masses May mimic neoplasia: Discrete, rounded or lobulated, subpleural nodules Pleural abnormalities & lung nodules, when present, help distinguish RA-related interstitial lung disease from UIP Airway disease Bronchiectasis & bronchial wall thickening: Earliest thoracic finding Constrictive bronchiolitis Mosaic attenuation/expiratory air-trapping Cylindrical bronchiectasis & bronchial wall thickening Micronodules < cm, centrilobular, subpleural, peribronchial Centrilobular nodules & tree-in-bud opacities in follicular bronchiolitis Bronchocentric granulomatosis: Bronchocentric nodules, similar to rheumatoid nodules Follicular bronchiolitis Rare Caused by lymphoid follicular hyperplasia along airways Centrilobular nodules & peribronchial thickening Drug reaction RA-related treatment may lead to infiltrative lung disease Drug treatment may produce constrictive bronchiolitis Corticosteroids: Opportunistic infection Gold: Ground-glass opacity along bronchovascular bundles; COP Methotrexate: Subacute hypersensitivity pneumonitis; NSIP Anti-tumor necrosis factor-α antibodies: Mycobacterial or fungal pneumonia Other findings Pulmonary hypertension, lymphadenopathy, mediastinal fibrosis, & pericardial effusion or thickening 783 Diagnostic Imaging Chest Imaging Recommendations Best imaging tool HRCT useful to characterize pattern & extent of RA-related lung & airway disease CT useful for evaluation of RA-related pleural disease P.7:6 DIFFERENTIAL DIAGNOSIS Idiopathic Pulmonary Fibrosis (IPF) May exhibit identical imaging findings: Peripheral, basilar fibrosis with honeycombing on HRCT Absence of pleural, pericardial, & airways disease No skeletal erosions Scleroderma May exhibit identical imaging findings: NSIP pattern on HRCT Dilated esophagus: Relaxation of lower esophageal sphincter No joint erosions as in RA: Hallmark is acroosteolysis (resorption distal phalanx) Asbestosis May exhibit identical imaging findings: UIP pattern on HRCT May exhibit pleural plaques (± calcification) or thickening Occupational history is of paramount importance No skeletal erosions Cryptogenic Organizing Pneumonia Bilateral or unilateral, patchy consolidations, or ground-glass opacities; often subpleural or peribronchial Basilar irregular linear opacities PATHOLOGY General Features Etiology Possible inflammatory, immunologic, hormonal, & genetic factors Subacute or chronic inflammatory polyarthropathy of unknown cause Interstitial lung disease Usual interstitial pneumonia Nonspecific interstitial pneumonia Cryptogenic organizing pneumonia Airways disease Bronchiectasis or bronchitis Constrictive bronchiolitis Follicular bronchiolitis Microscopic Features Pulmonary fibrosis: Usually UIP or NSIP pattern Other pulmonary findings: Interstitial pneumonitis, COP, lymphoid follicles, rheumatoid nodules (pathognomonic) Pleural biopsy: May show rheumatoid nodules Pleural fluid: Lymphocytes, acutely neutrophils & eosinophils Laboratory Abnormalities Pleural fluid: High protein, low glucose, low pH, high LDH, high RF, low complement Pulmonary function tests Restrictive pulmonary function, reduced diffusing capacity Obstructive defect if predominant airways disease CLINICAL ISSUES Presentation Most common signs/symptoms Primary sites of inflammation: Synovial membranes & articular structures Onset usually between 25 & 50 years Insidious onset, with relapses & remissions Other signs/symptoms Extraarticular RA: More common in men, age range of 50-60 years Thoracic symptoms Thoracic disease may develop before, at onset, or after onset of arthritis May be asymptomatic 784 Diagnostic Imaging Chest Dyspnea, cough, pleuritic pain, finger clubbing, hemoptysis, infection, bronchopleural fistula, pneumothorax Most affected patients have arthritis; positive rheumatoid factor (RF) (80%) & cutaneous nodules Demographics Age Any age, but more common in middle-aged adults Gender 3x more common in women Epidemiology Thoracic involvement much more common in men Pleural disease common; 40-75% in postmortem studies Natural History & Prognosis 5-year survival: 40% Death from infection, respiratory failure, cor pulmonale, amyloidosis Infection is most common cause of death Treatment Treatment: Corticosteroids, immunosuppressant drugs Drugs used to treat RA may cause interstitial lung disease Methotrexate Gold D-penicillamine Anti-tumor necrosis factor-α antibodies DIAGNOSTIC CHECKLIST Consider RA-related lung disease in patient with lung fibrosis & history of RA or polyarthritis (especially with distal clavicular resorption) Image Interpretation Pearls Hand radiographic abnormalities &/or findings of distal clavicle erosions are useful for differentiating RA from other interstitial lung diseases SELECTED REFERENCES Lynch DA: Lung disease related to collagen vascular disease J Thorac Imaging 24(4):299-309, 2009 P.7:7 Image Gallery (Left) Axial NECT of a patient with pulmonary involvement by RA shows adjacent right upper lobe pulmonary nodules, one of which exhibits cavitation and a thick nodular wall (Right) Axial NECT of the same patient shows additional bilateral lung nodules, one with cavitation , consistent with rheumatoid nodules Rheumatoid nodules affect less than 5% of patients with RA The differential diagnosis includes cavitary metastases, septic emboli, vasculitis, and fungal or necrotizing pneumonia 785 Diagnostic Imaging Chest (Left) Axial expiratory HRCT of a patient with RA shows large regions of air-trapping secondary to RA-related constrictive bronchiolitis (Right) Coronal HRCT of the same patient shows bilateral mosaic attenuation and areas of air-trapping with intrinsic cylindrical bronchiectasis and bronchial wall thickening, consistent with constrictive bronchiolitis Although there is imaging overlap between constrictive bronchiolitis and asthma, the former produces irreversible airway obstruction (Left) Axial NECT of a patient with RA shows bilateral pleural thickening with partial calcification on the right There is an adjacent subpleural soft tissue mass in the right lower lobe (Right) Axial NECT of the same patient shows that the right lower lobe mass abuts the thickened pleura, exhibits the “comet tail” sign , and is associated with right lower lobe volume loss with posterior displacement of the right major fissure The findings are diagnostic of rounded atelectasis Scleroderma > Table of Contents > Section - Connective Tissue Disorders, Immunological Diseases, and Vasculitis > Immunological and Connective Tissue Disorders > Scleroderma Scleroderma Jonathan H Chung, MD Key Facts Terminology Generalized connective tissue disorder affecting multiple organs, including skin, lungs, heart, & kidneys Imaging Radiography Symmetric basal reticulonodular opacities 786 Diagnostic Imaging Chest Decreased lung volumes, sometimes out of proportion to lung disease Dilated, air-filled esophagus best seen on lateral CT Interstitial lung disease: Nonspecific interstitial pneumonia > > usual interstitial pneumonia Thin-walled subpleural cysts: 10-30 mm Esophageal dilatation (80%) Pulmonary arterial hypertension Lymphadenopathy (60-70%) Top Differential Diagnoses Idiopathic pulmonary fibrosis Aspiration pneumonia Nonspecific interstitial pneumonia Pathology Collagen overproduction & deposition in tissue Clinical Issues Pulmonary disease usually follows skin manifestations Increased risk of lung cancer, usually in patients with pulmonary fibrosis Poor prognosis; death usually from aspiration pneumonia Diagnostic Checklist Consider scleroderma in patient with chronic interstitial lung disease & dilated esophagus (Left) Axial HRCT of a patient with known scleroderma shows symmetric peripheral ground-glass and reticular opacities with subpleural sparing and a dilated distal esophagus (Right) Coronal NECT minIP image of the same patient shows basilar predominant lung disease and debris within a dilated esophagus , which is highly suggestive of esophageal dysmotility Esophageal dysmotility is commonly present in patients with scleroderma 787 ... D et al: Imaging lung disease in systemic sclerosis Curr Rheumatol Rep 12( 2):156-61, 20 10 Lynch DA: Lung disease related to collagen vascular disease J Thorac Imaging 24 (4) :29 9-309, 20 09 de Azevedo... high-resolution CT findings Radiographics 20 (6):1 623 -35, 20 00 12 Warrington KJ et al: The shrinking lungs syndrome in systemic lupus erythematosus Mayo Clin Proc 75(5):467- 72, 20 00 13 Murin S et al: Pulmonary... with air-trapping Imaging Recommendations Best imaging tool HRCT is optimal imaging modality for evaluation of interstitial lung & small airway diseases 807 Diagnostic Imaging Chest DIFFERENTIAL