Influenza A (H1N1) virus-associated pneumonia: high-resolution computed tomography-pathologic correlation.

OBJECTIVE: The purpose of this study was to describe the high-resolution computed tomography (HRCT) features of fatal cases of Influenza A (H1N1) virus-associated pneumonia and to correlate them with pathologic findings. METHODS: The study included six adult patients who died following Influenza A (H1N1) virus-associated pneumonia. All patients had undergone HRCT, and the images were retrospectively analyzed by two chest radiologists, who reached decisions by consensus. Two experienced lung pathologists reviewed all pathological specimens. The HRCT findings were correlated with the histopathologic data. RESULTS: The predominant HRCT findings included areas of airspace consolidation (n=6) and ground-glass opacities (n=3). The main pathological features consisted of diffuse alveolar damage with hyaline membrane formation (n=5), associated with various degrees of pulmonary congestion, edema, hemorrhage, inflammatory infiltration and bronchiolitis. A patient who survived longer showed findings of organizing pneumonia. CONCLUSION: Fatal cases of Influenza A (H1N1) virus-associated pneumonia can present as areas of consolidation on CT, with or without ground-glass opacities. These abnormalities can be pathologically correlated with diffuse alveolar damage. Patients with longer survival may present with findings of organizing pneumonia.

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.

Exogenous lipoid pneumonia. Clinical and radiological manifestations.

Lipoid pneumonia results from the pulmonary accumulation of endogenous or exogenous lipids. Host tissue reactions to the inhaled substances differ according to their chemical characteristics. Symptoms can vary significantly among individuals, ranging from asymptomatic to severe, life-threatening disease. Acute, sometimes fatal, cases can occur, but the disease is usually indolent. Possible complications include superinfection by nontuberculous mycobacteria, pulmonary fibrosis, respiratory insufficiency, cor pulmonale, and hypercalcemia. The radiological findings are nonspecific, and the disease presents with variable patterns and distribution. For this reason, lipoid pneumonia may mimic many other diseases. The diagnosis of exogenous lipoid pneumonia is based on a history of exposure to oil, characteristic radiological findings, and the presence of lipid-laden macrophages on sputum or BAL analysis. High-resolution computed tomography (HRCT) is the best imaging modality for the diagnosis of lipoid pneumonia. The most characteristic CT finding in LP is the presence of negative attenuation values within areas of consolidation. There are currently no studies in the literature that define the best therapeutic option. However, there is a consensus that the key measure is identifying and discontinuing exposure to the offending agent. Treatment in patients without clinical symptoms remains controversial, but in patients with diffuse pulmonary damage, aggressive therapies have been reported. They include whole lung lavage, systemic corticosteroids, and thoracoscopy with surgical debridement.

Paravertebral mass in a patient with hemolytic anemia: computed tomographic findings.

Extramedullary hematopoiesis is characterized by the presence of hematopoietic tissue outside of the bone marrow and is typically associated with chronic hemolytic anemias. Intrathoracic extramedullary hematopoiesis is a rare and usually asymptomatic condition. The authors report a case of a 57-year-old man with intrathoracic extramedullary hematopoiesis and hereditary spherocytosis. Clinical and laboratory evaluation, together with radiological findings, are described. The diagnosis of the disease was confirmed by tissue biopsy.

Lipoid pneumonia in 53 patients after aspiration of mineral oil: comparison of high-resolution computed tomography findings in adults and children.

OBJECTIVE: To evaluate the high-resolution computed tomography (HRCT) findings in 53 patients with exogenous lipoid pneumonia and to compare the imaging features of adults and children. MATERIALS AND METHODS: The study included 35 children and 18 adults. Statistical comparisons of findings in the 2 age groups were performed using either Pearson chi2 or Fisher exact test, as appropriate, at 5% significance level. RESULTS: The main HRCT findings included air-space consolidation, ground glass attenuation, air-space nodules, and crazy-paving pattern. Abnormalities predominated in the posterior regions of the right lung. The right lower lobe was most likely to show severe involvement. CONCLUSIONS: The presence of air-space consolidation, the involvement of upper right lobe, and the central and posterior distribution of the lesions were more common in children, whereas the crazy-paving pattern and random localization were significantly more frequent in adults. The other findings were not different between the 2 groups.

Pulmonary talcosis: imaging findings.

Talc is a mineral widely used in the ceramic, paper, plastics, rubber, paint, and cosmetic industries. Four distinct forms of pulmonary disease caused by talc have been defined. Three of them (talcosilicosis, talcoasbestosis, and pure talcosis) are associated with aspiration and differ in the composition of the inhaled substance. The fourth form, a result of intravenous administration of talc, is seen in drug users who inject medications intended for oral use. The disease most commonly affects men, with a mean age in the fourth decade of life. Presentation of patients with talc granulomatosis can range from asymptomatic to fulminant disease. Symptomatic patients typically present with nonspecific complaints, including progressive exertional dyspnea, and cough. Late complications include chronic respiratory failure, emphysema, pulmonary arterial hypertension, and cor pulmonale. History of occupational exposure or of drug addiction is the major clue to the diagnosis. The high-resolution computed tomography (HRCT) finding of small centrilobular nodules associated with heterogeneous conglomerate masses containing high-density amorphous areas, with or without panlobular emphysema in the lower lobes, is highly suggestive of pulmonary talcosis. The characteristic histopathologic feature in talc pneumoconiosis is the striking appearance of birefringent, needle-shaped particles of talc seen within the giant cells and in the areas of pulmonary fibrosis with the use of polarized light. In conclusion, computed tomography can play an important role in the diagnosis of pulmonary talcosis, since suggestive patterns may be observed. The presence of these patterns in drug abusers or in patients with an occupational history of exposure to talc is highly suggestive of pulmonary talcosis.

Pulmonary metastases from primary hepatocellular carcinoma in a 26-year-old patient: a case report.

Hepatocellular carcinoma is a primary tumor of the liver, which usually develops in the setting of chronic liver disease, particularly viral hepatitis. The diagnosis of hepatocellular carcinoma can be difficult, and often requires the use of serum markers, one or more imaging modalities, and histological confirmation. The authors describe a case of a 26-year-old woman with hepatocellular carcinoma and multiple pulmonary metastases. She presented with hepatomegaly and sporadic fever, and had negative hepatitis serology, normal alkaline phosphatase, and a rising serum alpha-fetoprotein level. The diagnosis was confirmed by histopathology, after percutaneous liver biopsy. Although the patient was in good health condition and had few symptoms, there was no possibility of treatment due to the extension of the liver tumor and the number of pulmonary metastases.

Primary pulmonary mucosa-associated lymphoid tissue lymphoma computed tomography findings: a case report.

Primary pulmonary non-Hodgkin's lymphoma is a very rare neoplasm. It is most frequently represented by the mucosa-associated lymphoid tissue type. We describe a case of a 67-year-old woman who presented with fatigue, mild dyspnea, and consolidation on chest radiograph. The diagnosis of non-Hodgkin's lymphoma was established by transbronchial biopsy, and chemotherapy was then started. The patient was treated with 6 cycles of chemotherapy. She had good response to therapy and no progression of the disease was observed during a 4-year follow-up period. The clinical, radiological and histopathological features are described. This entity has an indolent course, good response to therapy and favorable prognosis. However, despite being an incidental radiological finding in a third of cases, this disease remains highly underdiagnosed.

Pulmonary nocardiosis in the acquired immunodeficiency syndrome, computed tomographic findings: a case report.

The authors describe a case of pulmonary nocardiosis in a 37-year-old man with acquired immunodeficiency syndrome in treatment with antiretroviral drugs. Clinical symptoms were productive cough, hemoptysis and progressive weight loss. A chest x-ray showed a right upper lobe consolidation while the computed tomography demonstrated consolidation with air bronchogram and airspace nodules. The radiologic findings were unspecific. Consequently, a bronchoscopy with bronchoalveolar lavage was performed, revealing filamentous Gram-positive bacteria (Nocardia species). Treatment with trimethoprim-sulfamethoxazole resulted in complete remission of the respiratory symptoms.