Miriam Menna Barreto

Microlitíase alveolar pulmonar: achados na tomografia computadorizada de alta resolução do tórax em 10 pacientes

OBJECTIVE To present the high-resolution computed tomography (HRCT) findings of pulmonary alveolar microlithiasis. METHODS The HRCT scans of 10 adult patients (seven females and three males; mean age, 38.7 years) were retrospectively analyzed. The films were studied independently by two radiologists. RESULTS The most common tomographic findings were ground-glass attenuation and linear subpleural calcifications, which were seen in 90% of the patients. Other relevant findings were small parenchymal nodules, calcification along the interlobular septa, nodular cissures, subpleural nodules, subpleural cysts, dense consolidations, and a mosaic pattern of attenuation. CONCLUSIONS The HRCT findings presented by individuals with pulmonary alveolar microlithiasis are distinct. In most cases, such findings can form the basis of the diagnosis, eliminating the need to perform a lung biopsy.

Correlation between computed tomographic and magnetic resonance imaging findings of parenchymal lung diseases.

Computed tomography (CT) is considered to be the gold standard method for the assessment of morphological changes in the pulmonary parenchyma. Although its spatial resolution is lower than that of CT, MRI offers the advantage of characterizing different aspects of tissue based on the degree of contrast on T1-weighted image (WI) and T2-WI. In this article, we describe and correlate the MRI and CT features of several common patterns of parenchymal lung disease (air trapping, atelectasis, bronchiectasis, cavitation, consolidation, emphysema, ground-glass opacities, halo sign, interlobular septal thickening, masses, mycetoma, nodules, progressive massive fibrosis, reverse halo sign and tree-in-bud pattern). MRI may be an alternative modality for the collection of morphological and functional information useful for the management of parenchymal lung disease, which would help reduce the number of chest CT scans and radiation exposure required in patients with a variety of conditions.

Can chest high-resolution computed tomography findings diagnose pulmonary alveolar microlithiasis?

Objective The present study was aimed at retrospectively reviewing high-resolution computed tomography (HRCT) findings in patients with pulmonary alveolar microlithiasis in order to evaluate the frequency of tomographic findings and their distribution in the lung parenchyma. Materials and Methods Thirteen patients (9 females and 4 males; age, 9 to 59 years; mean age, 34.5 years) were included in the present study. The HRCT images were independently evaluated by two observers whose decisions were made by consensus. The inclusion criterion was the presence of abnormalities typical of pulmonary alveolar microlithiasis at HRCT, which precludes lung biopsy. However, in 6 cases lung biopsy was performed. Results Ground-glass opacities and small parenchymal nodules were the predominant tomographic findings, present in 100% of cases, followed by small subpleural nodules (92.3%), subpleural cysts (84.6%), subpleural linear calcifications (69.2%), crazy-paving pattern (69.2%), fissure nodularity (53.8%), calcification along interlobular septa (46.2%) and dense consolidation (46.2%). Conclusion As regards distribution of the lesions, there was preferential involvement of the lower third of the lungs. No predominance of distribution in axial and anteroposterior directions was observed.

Pulmonary artery sarcoma mimicking chronic pulmonary thromboembolism.

A 35-year-old woman was admitted in our institution with a 2-year history of dyspnea, hemoptysis and chest pain. Chest computed tomography (CT) demonstrated filling defects in the right pulmonary artery and some of its branches (Figure 1A). Transthoracic echocardiography showed right heart chambers enlargement and increased pulmonary artery systolic pressure. These test results associated to the patient’s clinical history, allowed for the diagnosis of chronic pulmonary thromboembolism (PTE). After six months of treatment without clinical improvement, a new contrast enhanced CT revealed a growing intraluminal filling defect and a lobulated mass on the right pulmonary artery and its branches, with areas of contrast enhancement (Figure 1 – B,C,D). In addition to the CT findings, magnetic resonance imaging identified restriction of water diffusion. These imaging findings yielded the diagnosis of pulmonary artery sarcoma (PAS). A significant clinical worsening was observed and the patient died before she could be submitted to a diagnostic/therapeutic surgical procedure. Vascular lesions of the chest have not been frequently described in the Brazilian radiological literature. PAS is a rare malignant tumor that develops from mesenchymal cells in the intima of the pulmonary artery. In general, it affects the central pulmonary arteries, close to the pulmonary valve, resulting in significant morbidity and high mortality rates. There is no predilection for sex, occurring most commonly in the fifth decade of life. In general, symptoms are nonspecific with dyspnea, cough, hemoptysis, chest pain and weight loss, progressing to pulmonary hypertension, right ventricular failure, and possibly chronic cor pulmonale. Clinical and radiological findings are frequently similar to thromboembolic disease. Due to its rarity and insidious growth pattern, PAS may be diagnosed as chronic PTE, leading to a diagnostic delay and inappropriate therapy such as anticoagulation or prolonged thrombolysis. At imaging studies, PAS presents as unilateral, intravascular lobulated masses with heterogeneous contrast enhancement, that may cause vascular distension and local extravascular dissemination. Also, the lungs are frequently affected by metastases. According to Yi et al., tomographic findings suggesting the diagnosis of PAS include low attenuation filling defect of the entire luminal diameter of a segment or of the whole extent of the main pulmonary artery, enlargement of the involved arteries and

Immunoreactivity of five antigens of Mycobacterium tuberculosis in patients attending a public health care facility in an area with high endemicity for TB

The objective of this study was to evaluate people attending a primary health clinic in Rio de Janeiro, Brazil for immunoreactivity to five Mycobacterium tuberculosis antigens, as these antigens are markers of immune response and factors associated with active TB. The serum antibody titers of different categories of patients (defined by microbiological and radiological characteristics and by response to therapy on follow‐up) to 38 kDa, 16 kDa, MPT64, ESAT‐6 and MT10.3 antigens were determined blind with ELISA. Positive tests to each antigen were defined with ROC analysis. OR were calculated for factors associated with humoral response in patients with active TB. A total of 201 patients underwent serological testing. Patients with confirmed active TB responded more frequently to MPT64 (44%), 16 kDa (37.7%) and 38 kDa (36.1%). ESAT‐6 and MT10.3 were also able to distinguish people in TB groups from controls. TB infected subjects responded less frequently to ESAT‐6 and MT10.3 (3.7% and 11%, respectively). Sensitivity and specificity to all antigens combined were 58.4% and 60.7%, respectively. Reactivity to 38 kDa and to MPT64 was more likely among alcohol users OR 2.61 (95%CI;1.05–6.94) and OR 3.27 (95%CI;1.33–8.15), respectively. 16 kDa antigen elicited a more protective response among smokers, OR 0.29 (95%CI; 0.10–0.83). It was concluded that reactivity to all antigens tested represented markers of active disease. ESAT‐6 and MT10.3 could not be identified as markers of TB infection in this community. Sensitivity was higher to all antigens combined, but at a cost of lower specificity. Interestingly, among factors associated with positive immunoreactivity, alcohol use and smoking seem to polarize the humoral response in different directions. This finding deserves further investigation.

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.

Influenza A (H1N1) pneumonia: HRCT findings

OBJECTIVE: To describe aspects found on HRCT scans of the chest in patients infected with the influenza A (H1N1) virus. METHODS: We retrospectively analyzed the HRCT scans of 71 patients (38 females and 33 males) with H1N1 infection, confirmed through laboratory tests, between July and September of 2009. The HRCT scans were interpreted by two thoracic radiologists independently, and in case of disagreement, the decisions were made by consensus. RESULTS: The most common HRCT findings were ground-glass opacities (85%), consolidation (64%), or a combination of ground-glass opacities and consolidation (58%). Other findings were airspace nodules (25%), bronchial wall thickening (25%), interlobular septal thickening (21%), crazy-paving pattern (15%), perilobular pattern (3%), and air trapping (3%). The findings were frequently bilateral (89%), with a random distribution (68%). Pleural effusion, when observed, was typically minimal. No lymphadenopathy was identified. CONCLUSIONS: The most common findings were ground-glass opacities and consolidations, or a combination of both. Involvement was commonly bilateral with no axial or craniocaudal predominance in the distribution. Although the major tomographic findings in H1N1 infection are nonspecific, it is important to recognize such findings in order to include infection with the H1N1 virus in the differential diagnosis of respiratory symptoms.

Computed tomography findings in patients with H1N1 influenza A infection

The present study aimed to review high resolution computed tomography findings in patients with H1N1 influenza A infection. The most common tomographic findings include ground-glass opacities, areas of consolidation or a combination of both patterns. Some patients may also present bronchial wall thickening, airspace nodules, crazy-paving pattern, perilobular opacity, air trapping and findings related to organizing pneumonia. These abnormalities are frequently bilateral, with subpleural distribution. Despite their nonspecificity, it is important to recognize the main tomographic findings in patients affected by H1N1 virus in order to include this possibility in the differential diagnosis, characterize complications and contribute in the follow-up, particularly in cases of severe disease.

Competence of senior medical students in diagnosing tuberculosis based on chest X-rays

OBJECTIVE To evaluate the competence of senior medical students in diagnosing tuberculosis (TB) based on their reading of chest X-rays, as well as to identify the factors associated with high scores for the overall interpretation of chest X-rays. METHODS In October 2008, a convenience sample of senior medical students who had undergone formal training in radiology at the Federal University of Rio de Janeiro School of Medicine, in the city of Rio de Janeiro, Brazil, were invited to participate in the study. Six chest X-rays (three of TB patients and three of patients without TB) were selected. Participants were asked to choose one of the three probable radiological interpretations, and one of the four subsequent suitable clinical approaches. They also completed a questionnaire designed to collect data related to demographics, career of interest, time spent in emergency rooms and year of study. The sensitivity and specificity related to competence in the radiological diagnosis of TB, as well as a score for the overall interpretation of chest X-rays, were calculated. RESULTS The sensitivity of the probable radiological diagnosis of pulmonary TB, based on the three chest X-rays of patients with TB (minimal, moderate and extensive) was 86.5%, 90.4% and 94.2%, respectively, and the specificity was 90%, 82% and 42%. The only factor associated with a high score for the overall radiological interpretation was the year of study. CONCLUSIONS In this sample of medical students, who had received formal training in radiology early in their medical school course, the competence in interpreting the chest X-rays of TB patients was good. The year of study seems to influence overall chest X-ray reading skill.

Organizing pneumonia: chest HRCT findings.

OBJECTIVE: To determine the frequency of HRCT findings and their distribution in the lung parenchyma of patients with organizing pneumonia. METHODS: This was a retrospective review of the HRCT scans of 36 adult patients (26 females and 10 males) with biopsy-proven organizing pneumonia. The patients were between 19 and 82 years of age (mean age, 56.2 years). The HRCT images were evaluated by two independent observers, discordant interpretations being resolved by consensus. RESULTS: The most common HRCT finding was that of ground-glass opacities, which were seen in 88.9% of the cases. The second most common finding was consolidation (in 83.3% of cases), followed by peribronchovascular opacities (in 52.8%), reticulation (in 38.9%), bronchiectasis (in 33.3%), interstitial nodules (in 27.8%), interlobular septal thickening (in 27.8%), perilobular pattern (in 22.2%), the reversed halo sign (in 16.7%), airspace nodules (in 11.1%), and the halo sign (in 8.3%). The lesions were predominantly bilateral, the middle and lower lung fields being the areas most commonly affected. CONCLUSIONS: Ground-glass opacities and consolidation were the most common findings, with a predominantly random distribution, although they were more common in the middle and lower thirds of the lungs.