Clinical Presentation

The clinical manifestations of DAH with or without capillaritis are relatively similar, and consist of cough, dyspnea, and hemoptysis, usually over a few days’ or weeks’ duration. Note that the absence of hemoptysis does not exclude DAH because hemoptysis may occur later in the course of a patient’s presentation, or occasionally will not be seen at all, even with extensive alveolar bleeding. However, at least with extensive bleeding, the patient’s hematocrit usually falls; when combined with extensive thoracic imaging findings and the proper clinical context, this should suggest the correct diagnosis. As a result of repeated hemorrhage, iron deficiency anemia may be present. In patients with DAH associated with connective tissue or rheumatologic syndromes, inflammation in other organ systems, such as sinusitis, arthritis, and glomerulonephritis, may be present. Increasingly bloody sequential bronchoalveolar lavage, often with hemosiderin-laden macrophages, confirms the diagnosis of DAH, but is not specific for the underlying insult producing the hemorrhage. In particular, when pulmonary-renal syndromes are responsible for DAH, red cell casts and proteinuria are often found in the urine. The erythrocyte sedimentation rate is frequently elevated in patients with DAH, but is a nonspecific finding.

Radiography

Chest radiography in patients with DAH of any cause will show focal, multifocal, or diffuse ground-glass opacity and/or consolidation, usually in the presence of a normal heart size and without pleural effusion. Findings often predominate in the dependent regions of lung and, in most patients, appear relatively quickly. A reverse bat wing appearance may occasionally be seen. Shortly after the appearance of lung opacities, a linear and reticular network may be evident superimposed on the regions of ground-glass opacity, representing interlobular septal thickening. The pulmonary opacities clear slowly over a period of 7 to 14 days if there are no superimposed processes or repeated episodes of alveolar hemorrhage. Recurrent bouts of alveolar hemorrhage may produce areas of fibrosis and scarring, manifesting on chest radiography as areas of coarse linear and reticular opacity with architectural distortion.

CT

CT and high-resolution CT (HRCT) typically show multifocal or diffuse bilateral ground-glass opacity and consolidation. Ground-glass attenuation poorly defined nodules (Fig. 101-1) may occur. Often, a network pattern of smooth interlobular septal thickening is superimposed in the regions of ground-glass opacity.

FIGURE 101-1 Diffuse alveolar hemorrhage: centrilobular nodules. This axial CT scan shows diffuse ground-glass opacity centrilobular nodules found to represent pulmonary hemorrhage on biopsy.

Clinical Presentation

Patients with WG typically present with fever and upper respiratory symptoms, such as nasal discharge and sinus symptoms. Constitutional symptoms, such as fatigue, weight loss, and malaise, are common. Cough, hemoptysis, shortness of breath and chest pain are common in patients with pulmonary involvement. Skin lesions, hearing loss, and ulcers in the oral and nasal cavities may occur. C-ANCA antibodies (antineutrophil cytoplasmic autoantibodies) with PR-3 specificity are elevated in more than 90% of patients with WG. C-ANCA antibodies are relatively specific for WG, but may be seen in microscopic polyangiitis, although protoplasmic-staining antineutrophil cytoplasmic antibodies (p-ANCA) is more suggestive of the latter. P-ANCA antibodies are seen in about 25% of patients with WG.

Radiography

Chest radiographs are abnormal in up to 85% of patients with WG at some point during the course of the illness. The most characteristic imaging manifestation of WG is multiple, usually bilateral, nodules or masses typically measuring 2 to 4 cm, often associated with cavitation (Fig. 101-2). Pulmonary opacities and cavities in patients with WG may occasionally be much larger. WG-related pulmonary cavities often have a rather thick, irregular internal wall, and air-fluid levels are occasionally seen. Ground-glass opacity surrounding the cavities is a frequent finding and is usually caused by adjacent alveolitis or pulmonary hemorrhage.

FIGURE 101-2 Wegener’s granulomatosis, lung cavities. This frontal chest radiograph shows multiple cavities of variable wall thickness. Solid nodules are also present bilaterally.

CT

Thoracic CT scanning in patients with WG also typically shows multiple bilateral nodules and/or masses,¹ and is far more sensitive for the detection of cavitation than chest radiography. In fact, most nodules measuring more than 2 cm in patients with WG will show cavitation on CT (Fig. 101-3). Nodules and cavities in patients with WG have no particular zonal predilection, and are somewhat randomly distributed throughout the lungs.

FIGURE 101-3 Wegener’s granulomatosis, lung cavity. This axial CT scan shows an irregular-appearing subpleural right lung cavity of indeterminate wall thickness.

Patchy multifocal or diffuse ground-glass opacities, often with areas of consolidation,¹ is the second most common thoracic imaging manifestation of WG, and may occur in the absence of pulmonary nodules. These opacities are usually the result of pulmonary hemorrhage. Occasionally, areas of consolidation may be subpleural or peribronchiolar in distribution, simulating organizing pneumonia; the so-called atoll or reverse halo sign may also be seen (Fig. 101-4).

FIGURE 101-4 Wegener’s granulomatosis, atoll sign. This axial CT scan shows bilateral subpleural opacities with central ground-glass attenuation and peripheral consolidation, consistent with the atoll or reverse ground-glass halo sign. The appearance is suggestive of organizing pneumonia.

Tracheobronchial wall thickening and narrowing may be present in patients with WG,¹ and may even lead to atelectasis. Typically, airway involvement in patients with WG predominates in the subglottic region and extends a variable distance caudally (Fig. 101-5). The airway wall thickening is circumferential and often nodular and irregular, occasionally resulting in tracheobronchial stenosis. The tracheobronchial thickening may occasionally calcify.

FIGURE 101-5 Wegener’s granulomatosis, diffuse tracheobronchial thickening. This axial CT scan shows circumferential, noncalcified tracheal thickening.

Pleural effusions and lymphadenopathy may occur in patients with WG, but are nonspecific findings and are relatively uncommon overall.

Pulmonary parenchymal opacities in patients with WG may resolve during treatment. Cavities may occasionally even enlarge during treatment, although wall thickness usually becomes progressively thinner and the internal wall character becomes smoother.

From Clinical Presentation

A number of serologic abnormalities may be seen in patients with WG, including anemia, elevated rheumatoid factor, and elevated erythrocyte sedimentation rate, and other uncommon serologic test results. Most of these laboratory findings are fairly nonspecific. Recurrent alveolar hemorrhage is common in patients with WG, is often subclinical and may lead to the detection of hemosiderin-laden macrophages on bronchoscopy with lavage. The most useful test for the evaluation of patients with WG is the c-ANCA antibody, which is elevated in more than 90% of patients with WG. C-ANCA antibody titers may also be used to follow disease course. Although c-ANCA antibody titers may be elevated in other diseases, in the proper clinical context and with suggestive radiologic features, the diagnosis of WG can be confidently established when c-ANCA antibodies are present.

The term limited Wegener’s granulomatosis refers to a clinical syndrome essentially identical to the full-blown WG syndrome but without systemic (especially renal) involvement clinically; upper respiratory tract manifestations are usually present. Histopathologically, WG manifestations are often present in the viscera of patients with limited WG, and therefore it is probably appropriate to consider limited WG as one end of the spectrum of WG rather than as a separate condition.

Clinical Presentation

The average age of onset is about 50 years, and men are more commonly affected than women.² Fever and constitutional symptoms, such as weight loss and malaise, are common in patients with microscopic polyangiitis. Patients also often complain of myalgias and arthralgias, and individually affected organ systems may also produce particular symptoms. For example, involvement of the gastrointestinal tract may produce diarrhea and bleeding, whereas involvement of the skin may produce dermatologic manifestations, such as purpura and splinter hemorrhages. Peripheral neuropathy may occur. Shortness of breath, cough, and hemoptysis are the more common symptoms of thoracic involvement, and hemoptysis may be life-threatening.

Radiography

Chest radiographs typically show multifocal bilateral areas of ground-glass opacity and/or consolidation related to alveolar hemorrhage.

CT

HRCT will show multifocal areas of ground-glass opacity, possibly with consolidation; smooth interlobular septal thickening may be associated with the areas of ground-glass opacity. Poorly defined ground-glass opacity centrilobular nodules, reflecting prior pulmonary hemorrhage and the presence of hemosiderin-laden macrophages, may be seen. Pleural effusion may occur, but is uncommon.

From Clinical Presentation

Patients with microscopic polyangiitis typically have elevated erythrocyte sedimentation rates, and other rheumatologic markers, such as rheumatoid factor and antinuclear antibody, may be elevated. These findings are ultimately nonspecific. An elevated p-ANCA antibody directed against myeloperoxidase is associated with microscopic polyangiitis and may be diagnostic in the context of the proper clinical and imaging findings. However, p-ANCA antibodies may be elevated in other vasculitides, such as Churg-Strauss syndrome and pauci-immune capillaritis. Therefore, a tissue diagnosis, usually obtained from the lung via surgical lung biopsy, is often required.

Clinical Presentation

Males are much more commonly affected than females in patients with Behçet syndrome. The typical age of diagnosis is 20 to 30 years, and Behçet syndrome is most commonly encountered in the Middle East, Mediterranean countries, and Japan.³ Patients usually present with chronic remitting oral and genital ulcers and skin lesions, especially erythema nodosum, as well as uveitis. A number of systemic manifestations are common in Behçet syndrome, including arthritis, neuropathy, thrombophlebitis, and aneurysm formation. Thoracic involvement usually occurs in the setting of established disease, with patients complaining of chest pain, shortness of breath, cough, and hemoptysis. Hemoptysis may be massive and life-threatening and is the cause of death in up to 39% of patients.

Radiography

Chest radiographs in patients with Behçet syndrome may show multifocal or diffuse bilateral air space opacities in patients with thoracic symptoms and hemoptysis; these findings are nonspecific and resemble those of other causes of DAH.³ Much more characteristic of Behçet syndrome is the presence of pulmonary artery aneurysms. On chest radiographs, pulmonary artery aneurysms appear as central hilar prominence or perihilar rounded opacity of variable size (Fig. 101-6A).³ Aneurysms may grow rapidly, and therefore a rapid change in the appearance of the hilum may be suggestive of aneurysm development in the proper context. The margins of the aneurysms may be poorly defined because of surrounding pulmonary hemorrhage.

FIGURE 101-6 Behçet syndrome, pulmonary artery aneurysm. A, Frontal chest radiograph shows rounded, poorly defined opacity in the left retrocardiac region representing a pulmonary artery aneurysm. The poorly defined nature of the lesion suggests surrounding hemorrhage. A smaller lesion is present on the right. B, Sagittal thoracic CT scan shows pulmonary artery aneurysm in left lower lobe.

CT

CT is clearly much more sensitive for the detection and characterization of pulmonary artery aneurysms (see Fig. 101-6B), and may even detect thrombosed pulmonary artery aneurysms that would be difficult to detect by catheter pulmonary angiography. Behçet syndrome may closely resemble another condition associated with the development of pulmonary artery aneurysms and venous thrombosis, Hughes-Stovin syndrome.

Thrombotic complications are also common in patients with Behçet syndrome and may involve the great veins of the thorax and the proximal pulmonary arteries.³ Pulmonary arterial thrombosis or emboli, as well as vasculitis, may produce pulmonary infarction, which usually manifests on chest radiographs or CT scans as a subpleural wedge-shaped consolidation.

Pleural effusions may occur in patients with Behçet syndrome, possibly caused by venous thrombosis or pulmonary infarction. Occasionally, the effusion may be chylous in nature.

Clinical Presentation

Classically, Takayasu arteritis has been divided into early (prepulseless) and late (pulseless) phases. Late-phase Takayasu arteritis may be further subclassified as classic pulseless disease (type I), a mixed type (type II), an atypical coarctation type (type III), and a dilated type (type IV). Most patients present with a form of late-phase disease.

During the early, inflammatory stage, fever, pain in the region of the inflamed vessels, myalgias, fatigue, and malaise are common. On physical examination, bruits or diminished pulse over the involved vessels may be detected. Ischemic symptoms may result when vascular stenoses or occlusions are present. When the brachiocephalic vessels are involved, neurologic symptoms may dominate the clinical picture.⁴

In the late occlusive phase, ischemic symptoms are the primary manifesting features, including angina, claudication, syncope, and visual impairment.⁴

CT

CT is useful for the early diagnosis of Takayasu arteritis because it allows evaluation of arterial wall thickness rather than just the luminal diameter. This is especially important because early diagnosis and treatment are associated with improved prognosis in patients with Takayasu arteritis. The findings of Takayasu arteritis on CT and CT angiography (CTA) include stenoses, occlusions, aneurysms (Fig. 101-7), and concentric arterial wall thickening affecting the aorta and its branches, as well as the the pulmonary arteries. Occasionally, coronary artery aneurysms may be seen. In late-stage Takayasu arteritis, extensive vascular calcification may occur.⁴ Limitations of CT include the need for iodinated contrast material and ionizing radiation, which may be particularly important given the typically young age of patients with Takayasu arteritis.

FIGURE 101-7 Takayasu arteritis, arterial aneurysm. This volume rendered thoracic CT image shows a large right subclavian artery aneurysm.

MRI

Advantages of MRI include the lack of need for ionizing radiation and iodinated contrast material, making MRI ideal for the serial evaluation of patients with Takayasu arteritis who are undergoing treatment. Furthermore, techniques such as cine MRI may show significant cardiovascular functional and hemodynamic abnormalities in patients with Takayasu arteritis, particularly aortic regurgitation. As with CT, MRI is useful for early diagnosis because of its ability to evaluate arterial wall thickness rather than just luminal narrowing.

Findings of Takayasu arteritis on MRI include mural thrombi, signal alterations within and surrounding inflamed vessels (Fig. 101-8), fusiform vascular dilation or frank aneurysm formation, thickened aortic valvular cusps, multifocal stenoses, and concentric thickening of the aortic wall. MRI may also show pericardial effusions and signal abnormalities within the pericardium, representing fluid and granulation tissue.⁴ The main disadvantages of MRI in patients with Takayasu arteritis include difficulty in visualizing small branch vessels and poor visualization of vascular calcification. MRI is also expensive, and is frequently less available in regions in which Takayasu arteritis is most prevalent.

FIGURE 101-8 Takayasu arteritis, vascular wall thickening and enhancement. This postcontrast T1-weighted image shows circumferential intense enhancement of the thickened brachiocephalic artery wall (arrowheads).

MR angiography provides detailed vascular information, including the location, degree, and extent of stenoses, as well as the presence of aneurysms. The patency of surgical bypass grafts may also be readily assessed.⁴

Angiography

Angiography has traditionally been the primary procedure for the diagnostic evaluation of Takayasu arteritis. Angiography often demonstrates long, smooth, tapered stenoses that range from mild to severe (Fig. 101-9). Arterial occlusions may be present, and collateral vessels or the subclavian steal phenomenon may be seen. Angiography is useful for guiding and evaluating interventional procedures, such as angioplasty or stent placement. However, angiography is invasive, may require a large amount of iodinated contrast material, delivers a substantial radiation dose, and can be difficult to perform in patients with long-segment stenoses or heavy arterial calcification. Additionally, angiography does not depict changes in wall architecture as well as cross-sectional techniques, and cannot differentiate between vascular narrowing caused by acute mural inflammation from that caused by chronic transmural fibrosis. Importantly, ischemic complications resulting from angiography in patients with Takayasu arteritis may be substantial, possibly because blood coagulation activity is increased in these patients.

FIGURE 101-9 Takayasu arteritis, vascular stenosis. This catheter pulmonary angiogram shows several stenoses, one high grade (arrow), in the right pulmonary arterial system.

From Clinical Presentation

Because histopathologic specimens are seldom available because of the large vessels commonly affected and because the histopathologic appearance of Takayasu arteritis can mimic that of other vasculitides, including temporal arteritis, the diagnosis of Takayasu arteritis is largely based on the combination of clinical information, laboratory evaluation, and diagnostic imaging.

Clinical Presentation

The following three stages of Churg-Strauss syndrome have been described:

Anemia is frequent as well. Cardiomyopathy is a common cause of death in patients with Churg-Strauss syndrome. A limited form of Churg-Strauss syndrome, with involvement of one organ system only, similar to limited Wegener’s granulomatosis, has been described. In such patients, the lung is rarely involved, and usually the gastrointestinal tract is affected.

Radiography

Chest radiographs are commonly abnormal in patients with Churg-Strauss syndrome, usually showing transient, nonsegmental, occasionally subpleural, consolidation.⁵ No particular zonal predilection has been noted. Occasionally, pulmonary opacities may be nodular in configuration (Fig. 101-10), somewhat resembling Wegener’s granulomatosis but, unlike Wegener’s granulomatosis, cavitation does not usually occur.

FIGURE 101-10 Churg-Strauss syndrome. This frontal chest radiograph shows multifocal bilateral pulmonary opacities, some nodular in appearance. Biopsy and clinical presentation indicated a diagnosis of Churg-Strauss syndrome.

CT

Thoracic CT findings in patients with Churg-Strauss syndrome include bilateral, subpleural ground-glass opacity or consolidation often accompanied by small centrilobular nodules.⁵

From Clinical Presentation

As with other vasculitides and numerous inflammatory processes, the erythrocyte sedimentation rate is usually elevated. Blood hypereosinophilia is usually present, typically more than 10% of the peripheral white blood cell count. The American College of Rheumatology diagnostic criteria for Churg-Strauss syndrome are presented in Box 101-1. Note that the presence of vasculitis is not among these criteria, because the presence of extravascular tissue eosinophilia is a more sensitive indicator of disease.

Clinical Presentation

Patients with giant cell arteritis often present with headache, malaise, joint aches, jaw claudication, fatigue, and polymyalgia rheumatica. Characteristically, pain on palpation over the temporal artery may be present. Patients are usually 50 years of age or older.

Ultrasound

Ultrasound may show a hypoechoic halo involving the temporal artery, representing vascular wall edema.

CT

Giant cell arteritis may produce visible thickening and enhancement of the walls of the affected large arteries, usually in a patchy fashion. These findings are best appreciated on unenhanced and enhanced (Fig. 101-11) CT studies. Stenoses and occlusions may occur. Bilateral pleural effusions may be seen, and a reticular and nodular pulmonary parenchymal pattern has been described. A larger nodular pattern has also been reported in patients with giant cell arteritis, but because there is some overlap between the pattern and areas of involvement in giant cell arteritis and other systemic vasculitides, such as Wegener’s granulomatosis and Churg-Strauss syndrome, it is not clear whether pulmonary nodules truly represent a manifestation of giant cell arteritis.

FIGURE 101-11 Giant cell arteritis, vascular wall thickening and enhancement. This postcontrast thoracic CT scan shows thickening and enhancement of the wall of the aorta.

Clinical Presentation

DAH with pulmonary capillaritis has occasionally been seen in patients with rheumatoid arthritis, polymyositis, scleroderma, and mixed connective tissue syndromes. DAH may be the initial manifestation of disease in some patients with connective tissue diseases, whereas in others it may be a late manifestation of disease. The clinical presentation of DAH in the setting of connective tissue disorders resembles other causes of alveolar hemorrhage.

CT

The imaging manifestations of DAH in the setting of connective tissue disease are similar to those of DAH in other clinical settings—multifocal or diffuse, usually bilateral, air space opacities, often a combination of ground-glass opacities and consolidation and often acute in onset. HRCT shows multifocal bilateral ground-glass opacity, often with smooth interlobular septal thickening; chronic or recurrent episodes may show poorly defined ground-glass attenuation centrilobular nodules. In patients with SLE, DAH should be distinguished from acute lupus pneumonitis. The latter is more common than DAH in SLE and usually manifests with multifocal or diffuse air space opacities, but usually with evidence of serosal membrane inflammation, such as pleural and pericardial effusions.

Radiography

On chest radiographs, necrotizing sarcoid granulomatosis has been reported to show multiple, bilateral small (10-mm) circumscribed nodules. The presentation may resemble a miliary pattern, although large nodules have also been reported as a manifestation of necrotizing sarcoid granulomatosis. Other reported appearances of necrotizing sarcoid granulomatosis include bilateral areas of air space consolidation, a solitary pulmonary nodule, and pleural effusion.

CT

HRCT will typically show that the nodules are distributed in a perilymphatic pattern, similar to classic sarcoidosis. Nodules may coalesce and cavitation may occur.

From Clinical Presentation

It is unclear whether necrotizing sarcoid granulomatosis represents a separate disease entity or is an unusual reaction in patients with sarcoidosis. Because necrotizing granulomas often have an infectious cause, it is very important that such causes be excluded before the diagnosis of necrotizing sarcoid granulomatosis is considered.

Clinical Presentation

IPH usually affects children and, much less commonly, young adults; children younger than 10 years are most commonly affected. Males are more commonly affected than females, at least with adult-onset disease. Patients with IPH characteristically present with hemoptysis. Other nonspecific symptoms, such as fever, cough, chest pain, shortness of breath, and iron deficiency anemia, may be present.⁷ Hemoptysis is not invariably seen. In some cases, the onset of disease is insidious, whereas in others, disease onset is acute. Some patients develop lymphadenopathy and hepatosplenomegaly.⁷ Later in the course of disease, with repeated episodes of hemorrhage, pulmonary fibrosis may develop, associated with other signs and symptoms, such as digital clubbing and progressive dyspnea or decreased exercise tolerance.

Radiography

Patients with IPH usually present with patchy, bilateral air space opacities with air bronchograms as a result of pulmonary hemorrhage. Findings may predominate in the mid and lower lungs and perihilar regions. Often, the pattern superficially resembles that of cardiogenic pulmonary edema, except that the vascular pedicle is usually not widened and cardiomegaly should be absent. Pleural effusions are also less common in patients with IPH than in patients with cardiogenic pulmonary edema. Asymmetric pulmonary opacities may occur in patients with IPH and, although rare, unilateral disease has been reported. The apices and costophrenic angles tend to be spared.

Over time, serial chest radiography characteristically shows pulmonary abnormalities evolving from ground-glass opacity and consolidation to areas of linear and reticular abnormalities. These abnormalities may resolve over a 1- to 2-week period. However, with repeated episodes of pulmonary hemorrhage, the areas of reticulation and linear abnormality may persist, often associated with architectural distortion, and represent developing pulmonary fibrosis.

CT

CT and HRCT in patients with IPH show findings typical of pulmonary hemorrhage—multifocal, bilateral, patchy or diffuse ground-glass opacities, with or without areas of air space consolidation associated with smooth interlobular septal thickening (Fig. 101-12). Findings tend to favor the dependent regions of the lung. Poorly defined ground-glass centrilobular nodules may be seen.

FIGURE 101-12 Idiopathic pulmonary hemosiderosis (IPH). This axial CT scan shows multifocal bilateral ground-glass opacity associated with mild interlobular septal thickening.

From Clinical Presentation

The diagnosis of IPH is one of exclusion. To consider the diagnosis of IPH, other causes of pulmonary hemorrhage must be addressed and excluded through a combination of imaging studies, careful clinical history and physical examination demonstrating repeated episodes of pulmonary hemorrhage associated with recurrent chest radiographic opacities consistent with pulmonary hemorrhage, and a series of laboratory examinations to rule out the possibility of other causes of pulmonary hemorrhage. Often, renal biopsy is required to obtain tissue for immunofluorescence and electron microscopy to exclude pulmonary-renal syndromes.

Clinical Presentation

Patients with Goodpasture syndrome are usually young adults, more often men. The main presenting complaint is hemoptysis, although this symptom is not invariably present. Typically, the hemoptysis in patients with Goodpasture syndrome develops before the onset of renal disease. Other common symptoms include fever, chest pain, shortness of breath, and fatigue. Hematuria and hypertension may occur in some patients, but these findings are unusual. At some point, an active urine sediment will occur, including proteinuria, and cellular or granular cell casts in the urine. This particular finding, in the setting of pulmonary hemorrhage or diffuse pulmonary opacities, is very suggestive of a pulmonary-renal syndrome, such as Goodpasture syndrome. In most patients, pulmonary and renal disease are present, but in a small percentage of patients, pulmonary disease without renal involvement may occur, as may the reverse.

The overall survival rate of Goodpasture syndrome is about 50%, with most deaths caused by DAH, often precipitated by pulmonary infection.

Radiography

Patients with Goodpasture syndrome usually present with patchy, bilateral air space opacities with air bronchograms related to pulmonary hemorrhage, very similar to IPH or other causes of DAH, with or without pulmonary capillaritis. Findings are often somewhat gravitationally dependent, predominating in the mid and lower lungs. As with IPH, the vascular pedicle is usually not widened and cardiomegaly should be absent; pleural effusions are also uncommon. The apices and costophrenic angles tend to be spared.

As with IPH or any cause of DAH, over time, serial chest radiographs characteristically show pulmonary abnormalities resolving, with areas of linear and reticular abnormalities developing, typically over a 1- to 2-week period, in the regions previously affected with ground-glass opacity and consolidation. With repeated episodes of pulmonary hemorrhage, the areas of reticulation and linear abnormality may persist, often associated with architectural distortion, representing developing pulmonary fibrosis.

CT

CT and HRCT in patients with Goodpasture syndrome show findings typical of pulmonary hemorrhage—multifocal, bilateral, patchy or diffuse ground-glass opacities (Fig. 101-13), with or without areas of air space consolidation associated with smooth interlobular septal thickening. Findings tend to favor the dependent regions of lung. Poorly defined ground-glass centrilobular nodules are common.

FIGURE 101-13 Goodpasture syndrome. This axial CT scan shows multifocal ground-glass opacity centrilobular nodules consistent with hemorrhage.

From Clinical Presentation

The diagnosis of Goodpasture syndrome is usually suspected when a young patient presents with hemoptysis and bilateral opacities on chest radiographs associated with urinalysis showing cellular or granular cell casts. Immunofluorescence or enzyme-linked immunosorbent assay confirmation of circulating or tissue anti–basement membrane antibodies is typically performed to establish the diagnosis. The diagnosis is usually confirmed with tissue from the kidney because the absence of proven pulmonary involvement does not exclude the diagnosis and, frequently, the linear pattern of immunofluorescence is more readily recognizable on renal, rather than pulmonary, biopsies.

KEY POINTS

Pulmonary vasculitis may involve small, medium, or large vessels.

Pulmonary vasculitis of any cause may present with pulmonary hemorrhage resulting from the presence of capillaritis.

Other suggestive imaging features are occasionally evident in specific causes of pulmonary vasculitis.