Noninfectious pulmonary complications after hematopoietic stem cell transplantation: practical approach to imaging diagnosis.

Hematopoietic stem cell transplantation (HSCT) is a widely available treatment for a variety of malignant and nonmalignant disorders. The treatment outcome is affected by the type of transplant and is limited by complications secondary to immunosuppression and treatment-related toxicity. Pulmonary complications are very common and follow a predictable timeline that reflects the immunologic status of the patient in the peritransplant period. Until recently, pulmonary complications were largely attributed to infectious causes. However, advances in diagnosis and treatment have led to a shift, and noninfectious complications have emerged as a major cause of morbidity and mortality in this population. With the increasing number of centers that perform HSCT, knowledge of posttransplant noninfectious pulmonary complications has become increasingly relevant. The basic principles of and indications for HSCT are described, and a timeline for the clinical, radiologic, and pathologic manifestations of noninfectious pulmonary complications is presented. Emphasis is given to high-resolution computed tomographic findings and the role of imaging in management of complications. A practical approach is provided to guide imaging interpretation and diagnosis of noninfectious pulmonary complications after HSCT.

Thoracic paracoccidioidomycosis: radiographic and CT findings.

Paracoccidioidomycosis (PCM) is the most common systemic mycosis in Latin America. Although most cases occur in developing countries, recent immigration patterns and an increase in travel have led to a growing number of PCM cases in the United States and Europe. PCM is caused by the dimorphic fungus Paracoccidioides brasiliensis, and the chronic form may progress to severe pulmonary involvement. Several radiologic patterns have been described for pulmonary PCM, including linear and reticular opacities, variable-sized nodules, patchy ill-defined opacities, airspace consolidation, and cavitary lesions. Fibrosis and paracicatricial emphysema are common associated findings. Chest computed tomography (CT) is the method of choice for evaluating pulmonary PCM, with the most common CT findings being ground-glass attenuation, consolidation, small or large nodules, masses, cavitations, interlobular septal thickening, emphysema, and fibrotic lesions. PCM is also an important cause of the "reversed halo" sign at high-resolution CT and should be considered in the differential diagnosis. Awareness of the multiple radiologic manifestations of PCM as well as its epidemiologic and clinical characteristics may permit early diagnosis and initiation of specific treatment, thereby reducing associated morbidity and mortality.

Comparative study of clinical, pathological and HRCT findings of primary alveolar proteinosis and silicoproteinosis.

OBJECTIVE: To compare the clinical, high-resolution computed tomography (HRCT) and pathological findings of primary alveolar proteinosis (PAP) and silicoproteinosis. MATERIAL AND METHODS: The study included 15 patients with PAP (6 women, 9 men, mean age 31 years) and 13 with silicoproteinosis (13 men, mean age 29.5 years). PAP was diagnosed by lung biopsy in 13 and bronchoalveolar lavage in two patients and silicoproteinosis by bronchoalveolar lavage in 10 and autopsy in three cases. HRCT images were reviewed by two chest radiologists with consensus for the presence, extent and distribution of ground-glass opacities, septal thickening, consolidation and nodules. Radiological-pathological correlation was performed by one radiologist and one chest pathologist. RESULTS: Seven (46%) patients with PAP were asymptomatic; the remainder presented slowly progressive dyspnea and dry cough. All silicoproteinosis patients had dry cough and rapidly progressive dyspnea. The most common HRCT finding on PAP was the crazy-paving pattern (93%). All cases had areas of geographic sparing in the affected lung. The most common finding in silicoproteinosis (92%) was dependent consolidation with calcification in 83%. Centrilobular nodules were common (85%). On pathology, both diseases demonstrated intra-alveolar accumulation of PAS material, thickening of interlobular septae and alveolar walls and no evidence of fibrosis. A few silica particles were seen in silicoproteinosis. CONCLUSION: Despite the pathological similarities, PAP and silicoproteinosis have distinct clinical and imaging features and prognosis. Bilateral crazy-paving pattern with areas of geographic sparing is characteristic for PAP. Silicoproteinosis presents with bilateral dependent consolidation often with areas of calcification. The crazy-paving pattern is not seen in silicoproteinosis.

Pulmonary paracoccidioidomycosis.

Paracoccidioidomycosis is a subacute or chronic systemic mycosis caused by Paracoccidioides brasiliensis, a soil saprophyte and thermally dimorphic fungus. The disease occurs mainly in rural workers in Latin America and is the most frequent endemic systemic mycosis in many countries of South America, where almost 10 million people are believed to be infected. Paracoccidioidomycosis should be regarded as a disease of travelers outside the endemic area. The primary pulmonary infection is subclinical in most cases, and individuals may remain infected throughout life without ever developing clinical signs. A small proportion of patients present with clinical disease. The lungs are frequently involved, and the pulmonary clinical manifestations must be differentiated from many other infectious and noninfectious conditions. Diagnosis should be based on epidemiological, clinical, and microbiological data. Effective treatment regimens are available to control the fungal infection, but most patients develop fibrotic sequelae that may severely hamper respiratory and adrenal function and the patient's well-being.

The reversed halo sign on high-resolution CT in infectious and noninfectious pulmonary diseases.

OBJECTIVE: The purpose of this article is to describe diseases that may present with the reversed halo sign on high-resolution CT. We emphasize the tomographic features most frequently associated with this sign and correlate them with histologic findings. CONCLUSION: A wide spectrum of infectious and noninfectious diseases may present with the reversed halo sign on chest CT. The nonspecific nature of this sign should not cloud an otherwise fairly straightforward diagnosis, especially when associated background findings are typical. Although a rigorous analysis of associated CT findings may help with the differential diagnosis, histologic assessment is often needed for a definitive determination of the cause.

Paracoccidioidomycosis: high-resolution computed tomography-pathologic correlation.

OBJECTIVE: The purpose of this study was to describe the high-resolution computed tomography (HRCT) features of pulmonary paracoccidioidomycosis and to correlate them with pathologic findings. METHODS: The study included 23 adult patients with pulmonary paracoccidioidomycosis. All patients had undergone HRCT, and the images were retrospectively analyzed by two chest radiologists, who reached decisions by consensus. An experienced lung pathologist reviewed all pathological specimens. The HRCT findings were correlated with histopathologic data. RESULTS: The predominant HRCT findings included areas of ground-glass opacities, nodules, interlobular septal thickening, airspace consolidation, cavitation, and fibrosis. The main pathological features consisted of alveolar and interlobular septal inflammatory infiltration, granulomas, alveolar exudate, cavitation secondary to necrosis, and fibrosis. CONCLUSION: Paracoccidioidomycosis can present different tomography patterns, which can involve both the interstitium and the airspace. These abnormalities can be pathologically correlated with inflammatory infiltration, granulomatous reaction, and fibrosis.

"Crazy-paving" patterns on high-resolution CT scans in patients with pulmonary complications after hematopoietic stem cell transplantation.

OBJECTIVE: To describe the pulmonary complications following hematopoietic stem cell transplantation (HSCT) that can present with a "crazy-paving" pattern in high-resolution CT scans. MATERIALS AND METHODS: Retrospective review of medical records from 2,537 patients who underwent HSCT. The "crazy-paving" pattern consists of interlobular and intralobular septal thickening superimposed on an area of ground-glass attenuation on high-resolution CT scans. The CT scans were retrospectively reviewed by two radiologists, who reached final decisions by consensus. RESULTS: We identified 10 cases (2.02%), seven male and three female, with pulmonary complications following HSCT that presented with the "crazy-paving" pattern. Seven (70%) patients had infectious pneumonia (adenovirus, herpes simplex, influenza virus, cytomegalovirus, respiratory syncytial virus, and toxoplasmosis), and three patients presented with non-infectious complications (idiopathic pneumonia syndrome and acute pulmonary edema). The "crazy-paving" pattern was bilateral in all cases, with diffuse distribution in nine patients (90%), predominantly in the middle and inferior lung regions in seven patients (70%), and involving the anterior and posterior regions of the lungs in nine patients (90%). CONCLUSION: The "crazy-paving" pattern is rare in HSCT recipients with pulmonary complications and is associated with infectious complications more commonly than non-infectious conditions.

Leptospirosis of the lung presenting with crazy-paving pattern: correlation between the high-resolution CT and pathological findings.

The authors present the high-resolution CT findings of a patient with diffuse pulmonary hemorrhage due to leptospirosis. The main finding consisted of extensive ground-glass opacities super imposed on mild interlobular septal thickening, resulting in the appearance termed "crazy- paving". The patient died and the necropsy showed extensive haemorrhage filling the airspace and blood infiltrating the interlobular sep- ta. The correlation between the high-resolution CT and pathological findings is emphasised.

Computed tomography findings in patients with tracheal paracoccidioidomycosis.

OBJECTIVE: To evaluate the high-resolution computed tomographic (CT) findings of patients with tracheal paracoccidioidomycosis. METHODS: The high-resolution CT scans of 178 patients with pulmonary paracoccidioidomycosis were reviewed, and 4 cases of proven tracheal involvement were studied. There were 3 male and 1 female patients, with ages ranging from 44 to 62 years (average, 49.2 years). The CT scans were retrospectively analyzed with special attention to the location of airway lesions, patterns of wall thickening, and occurrence of abnormal adjacent lymph nodes. Images were reviewed by 2 radiologists who reached decisions by consensus. RESULTS: The CT findings were circumferential parietal thickening (n = 4) and irregular (n = 3) or smooth (n = 1), with submucosal nodules (n = 2). Enlarged mediastinal lymph nodes were seen in 1 patient. CONCLUSIONS: The CT findings in patients with tracheal paracoccidioidomycosis were circumferential irregular thickening of the tracheal wall, with submucosal nodules.

AIDS-related Kaposi sarcoma of the lung presenting with a "crazy-paving" pattern on high-resolution CT: imaging and pathologic findings.

Kaposi sarcoma (KS) is a fulminate and disseminated form of acquired immunodeficiency syndrome (AIDS)-defining neoplasm, usually presenting pulmonary involvement. We report a 40-year-old woman with AIDS and biopsy-proven KS showing unusual high-resolution computed tomography (HRCT) findings. HRCT showed areas of ground-glass attenuation with superimposed septal thickening ("crazy-paving" pattern). CT-pathologic correlation revealed that crazy-paving pattern in this case was due to accompanying pulmonary edema and hemorrhage in addition to tumor cell infiltration into the peribronchovascular interstitium, interlobular and alveolar septa. The authors suggest the inclusion of KS in the differential diagnosis of lung diseases in patients with AIDS presenting with crazy-paving pattern on the HRCT.

Consolidation with diffuse or focal high attenuation: computed tomography findings.

This pictorial essay aims to present various lesions that could present as consolidations with diffuse of focal high attenuation on computed tomography, helping to make the diagnosis more confident and specific. The radiologic literature has limited information about such findings and the role of computed tomography in the differential diagnosis. The following diseases are presented: metastatic pulmonary calcification, pulmonary alveolar microlithiasis, amiodarone lung, talcosis, iodinated oil embolism, tuberculosis, silicoproteinosis, and amyloidosis. In conclusion, air-space consolidations can be seen in a wide variety of diseases affecting the lungs. The identification of the different patterns of consolidation with focal high attenuation narrows the differential diagnosis. We present a diagnostic approach based on appearance and distribution of these lesions.

Pulmonary infections following bone marrow transplantation: high-resolution CT findings in 35 paediatric patients.

PURPOSE: The purpose of this study was to assess the high-resolution CT findings of paediatric patients who had pulmonary infections following bone marrow transplantation (BMT), and to evaluate the differential diagnosis through high-resolution CT of the various pathogens responsible for pulmonary infections after BMT. PATIENTS AND METHODS: The study included 35 consecutive patients who had documented pulmonary infection, high-resolution CT of the chest performed within 24h of the beginning of symptoms, and proven diagnosis within 1 week of the onset of symptoms. The pulmonary infections were due to viruses (n=16), bacteria (n=9), fungi (n=9), and protozoa (n=1). Two radiologists analyzed the CT scans and reached final decisions regarding the findings by consensus. RESULTS: Four patients with confirmed pneumonia had normal high-resolution CT scans. Regarding the viral infections, the most frequent features were areas of ground-glass attenuation (43.7%) and small centrilobular nodules (31.2%). Airspace consolidation (88.9%), small centrilobular nodules (22.2%) and ground-glass attenuation (22.2%) were the most frequent findings in patients with bacterial pneumonia following BMT. Large nodules were seen in 66.7% of the patients with fungal pneumonia, and in only one case of virus infection. The "halo sign" (n=5) was seen only in patients with fungal pneumonia. CONCLUSION: In conclusion, the main causes of pulmonary infection in paediatric patients following BMT share similar high-resolution CT findings. Large nodules and "halo sign" are more common in patients with fungal infections.

Silicoproteinosis: high-resolution CT findings in 13 patients.

OBJECTIVE: The purpose of this study was to evaluate the high-resolution CT findings of silicoproteinosis. CONCLUSION: Silicoproteinosis usually manifests as bilateral consolidation in the posterior portions of the lungs and as numerous centrilobular nodules. Calcification within areas of consolidation is a common finding.

[Acute pulmonary schistosomiasis: correlation between the high-resolution CT and pathological findings]. / Schistosomíase pulmonar aguda: Correlação entre a tomografia computadorizada de alta resolução e os achados anatomopatológicos.

A 35 years old rural worker presented with a 15 days history of progressive dyspnea, associated with dry cough, myalgia and fever. Few days before the symptoms, he had swim in a river. The chest radio- graphs demonstrated bilateral reticule-nodular infiltrates. The high-resolution CT showed patchy areas of ground-glass attenuation, irregular inter- lobular septal thickening, intralobular interstitial thickening, and small nodules, which are confluent in some regions. All the laboratory investigations were negative. The open lung biopsy shows parenchymal granulomatous inflammation, and numerous schistosome ova.

Pneumonia lipoídica em adultos: aspectos na tomografia computadorizada de alta resolução / Lipoid pneumonia in adults: findings on high-resolution computed tomography

OBJETIVO: Apresentar os aspectos na tomografia computadorizada de alta resolução do tórax da pneumonia lipoídica exógena por aspiração de óleo mineral, em pacientes adultos MATERIAIS E MÉTODOS: Foram estudados oito pacientes adultos - quatro mulheres e quatro homens - com média de idade de 69,4 anos, todos usuários de óleo mineral para tratamento de constipação intestinal. Os exames foram avaliados por dois radiologistas, de forma independente RESULTADOS: Os achados tomográficos mais comuns foram as consolidações com áreas de densidade de gordura de permeio, e o padrão de pavimentação em mosaico. As lesões foram bilaterais em seis pacientes, e unilaterais em dois CONCLUSÃO: O encontro de consolidações pulmonares com áreas de densidade de gordura de permeio, associado à história clínica do uso de óleo mineral, é diagnóstico de pneumonia lipoídica exógena.

OBJECTIVE: The present study was aimed at describing the findings on high-resolution computed tomography in patients with exogenous lipoid pneumonia secondary to mineral oil aspiration MATERIALS AND METHODS: Eight adult patients - four men and four women - with mean age of 69.4 years were studied. All of the patients were users of mineral oil for treating intestinal constipation. High-resolution computed tomography studies of these patients were blindly evaluated by two radiologists. RESULTS: Air-space consolidation with areas of fat density and crazy paving pattern were the most frequent findings. The lesions were bilateral in six cases and unilateral in two CONCLUSION: Air-space consolidation with areas of fat density, associated with a clinical history of mineral oil ingestion virtually indicates a diagnosis of exogenous lipoid pneumonia.

Pulmonary paracoccidioidomycosis and AIDS: high-resolution CT findings in five patients.

OBJECTIVE: To study the high-resolution computed tomographic (HRCT) findings in patients with AIDS and pulmonary paracoccidioidomycosis (PCM). MATERIALS AND METHODS: The study included 5 consecutive patients (4 men and 1 woman, with ages ranging between 35 and 57 years; mean, 48 years) with diagnosis of AIDS and pulmonary PCM. All patients underwent HRCT, and the images were reviewed by 2 radiologists who reached decisions by consensus. RESULTS: The predominant HRCT findings in the present series were large nodules (80%), cavited air-space consolidations (80%), ground-glass attenuation (80%), and cicatricial emphysema in the bases (80%). These lesions predominated bilaterally in the middle regions (80%) of the lungs. CONCLUSIONS: The most common HRCT features in patients with AIDS and pulmonary PCM are large nodules associated with cavitated air-space consolidations and ground-glass attenuation, as well as cicatricial emphysema in the pulmonary bases. These findings are usually distributed bilaterally in the middle lung zones of the lungs.

Lipoid pneumonia in children following aspiration of mineral oil used in the treatment of constipation: high-resolution CT findings in 17 patients.

BACKGROUND: Exogenous lipoid pneumonia is a rare disorder caused by aspiration of mineral, vegetable and animal oils. High-resolution CT findings of lipoid pneumonia in children taking mineral oil for constipation have been rarely reported. OBJECTIVE: To evaluate the high-resolution CT findings in 17 children with exogenous lipoid pneumonia following aspiration of mineral oil. MATERIALS AND METHODS: The study included nine boys and eight girls, with ages ranging from 2 months to 9 years. All patients underwent high-resolution CT and the images were reviewed by two radiologists who reached decisions by consensus. The inclusion criteria were an abnormal radiograph, history of taking mineral oil and the presence of intrapulmonary lipids proved by bronchoalveolar lavage or open lung biopsy. RESULTS: The most common symptoms were cough (n = 13), mild fever (n = 11), and progressive dyspnea (n = 9). The main CT findings were air-space consolidations (100%), usually with areas of fatty attenuation (70.6%), areas of ground-glass attenuation (52.9%), and a crazy-paving pattern (17.6%), predominating bilaterally in the posterior and lower regions of the lungs. CONCLUSION: The high-resolution CT features in children with exogenous lipoid pneumonia are air-space consolidations and ground-glass attenuation, occasionally with a crazy-paving pattern, distributed bilaterally in the posterior and lower zones of the lungs.

Tumor de células gigantes do metatarso: relato de caso e revisão da literatura / Giant cell tumor of the metatarsal bone: case report and review of the literature

O tumor de células gigantes é uma neoplasia rara e representa 5% dos tumores ósseos primários. Acomete com maior freqüência joelho e punho, sendo raro em pequenos ossos do pé. Os autores apresentam um paciente do sexo masculino, 32 anos de idade, há quatro meses com dor no pé direito. A radiografia simples demonstrou lesão osteolítica e insuflante acometendo o primeiro metatarso do pé direito. A tomografia computadorizada revelou lesão radiolucente com bordas bem definidas. Foi realizada biópsia da lesão, cujo estudo histológico definiu o diagnóstico de tumor de células gigantes. Os autores enfatizam a correlação entre os achados de imagem e a histologia.

Giant cell tumor of bone is a rare neoplasm and account for 5% of all primary bone tumors. It is common in the knee and wrist, but rare in the small bones of the foot. The authors report a 32-yearold male patient presented with a four-month history of right foot pain. Plain radiographs showed an expansive lytic lesion involving the first right metatarsal bone. Computed tomography scan demonstrated a radiolucent lesion with well-defined borders. Biopsy was performed and the histological diagnostic was giant cell tumor. The authors emphasize the correlation between the imaging and histological findings.

Viral pneumonia after hematopoietic stem cell transplantation: high-resolution CT findings.

Hematopoietic stem cell transplantation (HSCT) is the treatment of choice for many hematologic malignancies and nonmalignant disorders of bone marrow function. Pulmonary infections from bacterial, fungal, and viral organisms are a major cause of morbidity and mortality in patients after HSCT. The radiographic and high-resolution computed tomography (HRCT) findings of the different lower respiratory tract viral infections are quite similar. Findings of viral pneumonia on HRCT include small poorly defined centrilobular nodules and patchy, often bilateral, areas of peribronchial ground-glass opacity and consolidation. Air trapping may be present because of associated bronchiolitis. Interlobular septal thickening, bronchial wall thickening, and tree-in-bud opacities may also be present. Advanced viral pneumonia with diffuse alveolar damage is characterized by patchy or confluent consolidation and ground-glass opacities. Although nonspecific, in the correct clinical setting, these HRCT findings can help suggest the diagnosis of viral pneumonia in recipients of HSCT.