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.     

Cytomegalovirus pneumonia after bone marrow transplantation: high resolution CT findings

Cytomegalovirus (CMV) pneumonia is one of the most common pulmonary complications after bone marrow transplantation (BMT). We describe the high resolution CT (HRCT) findings of 13 patients with CMV pneumonia diagnosed after allogenic BMT. The study included 13 consecutive patients who developed CMV pneumonia after BMT and who had HRCT of the chest performed within 24 h of the onset of symptoms. HRCT scans were reviewed by two radiologists who assessed pattern and distribution of findings. There were nine male and four female patients, ranging from 9 years to 56 years of age (mean age 33 years). BMT was performed for treatment of chronic myelogenous leukaemia (54%), severe aplastic anaemia (23%), acute myelogenous leukaemia (15%) and Fanconi's anaemia (8%). The time elapsed until diagnosis ranged from +18 days to +405 days (median of 54 days, mean +81.6 days). The predominant patterns of abnormality on HRCT scans were ground-glass opacities (69%), small centrilobular nodules (69%) and air-space opacities (54%). The abnormalities were distributed in the central and peripheral zones of the lungs in six cases, only in the periphery in four cases, and only in the central zone in three cases. In all cases the lung lesions were bilateral, and asymmetry was observed in seven cases. The authors conclude that the most common HRCT findings in patients with CMV pneumonia after BMT consist of bilateral asymmetric ground-glass, air-space opacities and small centrilobular nodules.     

Radiographic and high-resolution CT findings of influenza virus pneumonia in patients with hematologic malignancies

OBJECTIVE: We sought to describe the radiographic and high-resolution CT findings of influenza virus pneumonia in patients with hematologic malignancies. CONCLUSION: Radiologic findings of influenza virus pneumonia in immunocompromised patients consist of patchy or confluent consolidation and nodular opacities on chest radiography and ground-glass attenuation, consolidation, centrilobular nodules, and branching linear opacities on high-resolution CT.     

Pulmonary infections after bone marrow transplantation: high-resolution CT findings in 111 patients

OBJECTIVE: The purpose of this study was to review the high-resolution CT findings in patients with pulmonary infection after bone marrow transplantation and to determine distinguishing features among the various types of infection. MATERIALS AND METHODS: This study included 111 consecutive bone marrow transplant recipients who had documented pulmonary infection, high-resolution CT of the chest performed within 24 hr of the beginning of symptoms, and proven diagnosis within 1 week of the onset of symptoms. Two radiologists analyzed the CT scans and reached final decisions regarding the findings by consensus. Statistical analysis was performed using the Fisher's exact test and multivariate analysis; a p value of less than 0.05 was considered statistically significant. RESULTS: The pulmonary infections were due to viruses (n = 57), bacteria (n = 26), fungi (n = 21), and protozoa (n = 1). Six patients had more than one organism responsible for the infection. Nodules that were 1 cm or more in diameter were seen in 13 (62%) of 21 patients with fungal pneumonia, five (19%) of 26 patients with bacterial pneumonia (p = 0.0059), three (10%) of 30 with respiratory syncytial virus (RSV) pneumonia (p = 0.0001), and three (14%) of 22 with cytomegalovirus pneumonia (p = 0.0016). The halo sign was present in 10 of 21 patients with fungal pneumonia, two of 26 with bacterial pneumonia (p = 0.0026), three of 30 with RSV pneumonia (p = 0.0036), and one of 22 with cytomegalovirus pneumonia (p = 0.0015). There was no statistically significant difference in the prevalence of the other CT patterns including small nodules, ground-glass attenuation, and air-space consolidation among viral, bacterial, and fungal infections (all p > 0.05). CONCLUSION: The presence of large nodules and visualization of the halo sign are most suggestive of fungal infection. Other high-resolution CT patterns are not helpful in distinguishing among the various types of infection seen in bone marrow transplant recipients.     

Pulmonary tuberculosis presenting as acute respiratory failure: radiologic findings

PURPOSE: The purpose of this work was to describe the radiologic findings of pulmonary tuberculosis in patients who presented with acute respiratory failure. METHODS: We included patients who had newly diagnosed active pulmonary tuberculosis and who presented with acute respiratory failure. Initial chest radiographic (n = 17) and high-resolution CT (n = 11) findings of each patient were analyzed retrospectively. RESULTS: Of 1,010 patients with active pulmonary tuberculosis, 17 patients (1.7%) presented with acute respiratory failure. Nine (53%) of the 17 patients died. The most common initial chest radiographic findings were small nodular lesions (16/17; 94%), consolidation (13/17; 76%), and ground-glass opacity (12/17; 70%). Eleven (69%) of 16 nodular lesions, 9 of 13 (69%) consolidations, and 10 of 12 (83%) ground-glass opacities were bilateral. On HRCT (n = 11), miliary micronodular lesions were seen in 6 patients (55%), whereas bronchogenic spread of tuberculosis with disseminated centrilobular nodules and tree-in-bud appearance was seen in 5 patients (45%). Diffuse areas of ground-glass attenuation were seen in all six patients with miliary nodules and four of five patients with bronchogenic spread of tuberculosis. CONCLUSION: Patients with pulmonary tuberculosis occasionally present with acute respiratory failure. In this condition, chest radiograph most commonly shows bilateral small nodular lesions mixed with consolidation or ground-glass opacity, whereas HRCT demonstrates findings of miliary or bronchogenic disseminated tuberculosis with diffuse areas of ground-glass attenuation.     

Respiratory bronchiolitis, respiratory bronchiolitis-associated interstitial lung disease, and desquamative interstitial pneumonia: different entities or part of the spectrum of the same disease process?

OBJECTIVE: Our objective was to assess high-resolution CT findings of respiratory bronchiolitis, respiratory bronchiolitis-associated interstitial lung disease, and desquamative interstitial pneumonia and to determine whether these three entities could be reliably differentiated by radiologic criteria. MATERIALS AND METHODS: CT scans (1- to 3-mm collimation) were reviewed in 40 patients with pathologically proven respiratory bronchiolitis (n = 16), respiratory bronchiolitis-associated interstitial lung disease (n = 8), or desquamative interstitial pneumonia (n = 16). All patients with respiratory bronchiolitis and respiratory bronchiolitis-associated interstitial lung disease were cigarette smokers, and 85% of the patients with desquamative interstitial pneumonia had a history of smoking. CT scans were independently reviewed by two radiologists who assessed the pattern and distribution of abnormalities. RESULTS: The predominant abnormalities in respiratory bronchiolitis were centrilobular nodules (12 [75%] of 16 patients) and ground-glass attenuation (six [38%] of 16). No single abnormality predominated in the respiratory bronchiolitis-associated interstitial lung disease group; findings included ground-glass attenuation (four [50%] of eight), centrilobular nodules (three [38%] of eight), and mild fibrosis (two [25%] of eight). All patients with desquamative interstitial pneumonia showed ground-glass attenuation, and 10 (63%) of the 16 showed evidence of fibrosis. CONCLUSION: The significant overlap between the CT findings of respiratory bronchiolitis, respiratory bronchiolitis-associated interstitial lung disease, and desquamative interstitial pneumonia is consistent with the concept that they represent different degrees of severity of small airway and parenchymal reaction to cigarette smoke.     

Near drowning: thin-section CT findings in six patients

PURPOSE: The purpose of this study was to assess the thin-section CT findings of near drowning in six patients. METHOD: Thin-section (1 mm collimation) CT scans of six patients who experienced near drowning were retrospectively analyzed. The CT scans were performed 0-5 days (median 1 day) after near drowning. RESULTS: Thin-section CT findings included bilateral patchy or diffuse areas of ground-glass attenuation (n = 6) with geographic pattern (n = 3) and fine intralobular reticular opacities ("crazy-paving" appearance) (n = 3), ill-defined centrilobular nodules (n = 4), and air-space consolidation (n = 1). Distribution of ground-glass attenuation was predominantly central (n = 4) or diffuse (n = 2). Interstitial pulmonary emphysema and pneumomediastinum were present in two patients. CONCLUSION: The thin-section CT findings of near drowning consist of ground-glass opacities with or without associated reticular opacities and centrilobular nodules.     

Stenotrophomonas maltophilia pneumonia after bone marrow transplantation: case report with emphasis on the high-resolution CT findings

A 6-year-old female patient who underwent bone marrow transplantation because of Fanconi anaemia presented with fever, dyspnoea and cough 17 days after the procedure. The physical examination revealed diffuse crackles. Chest radiographs demonstrated diffuse alveolar opacities in both lungs. High-resolution CT showed a diffuse and bilateral lung lesion characterized by multifocal areas of air-space consolidation associated with ground-glass attenuation and small centrilobular nodules. The culture of the material obtained with bronchoalveolar lavage only demonstrated growth of Stenotrophomonas maltophilia. The patient rapidly presented respiratory insufficiency and death in the same day.     

Pulmonary candidiasis after hematopoietic stem cell transplantation: thin-section CT findings

PURPOSE: To retrospectively evaluate thin-section computed tomographic (CT) findings in hematopoietic stem cell transplant (ie, bone marrow transplant) patients with histopathologically proved pulmonary candidiasis. MATERIALS AND METHODS: Ethical approval was obtained from the institutional review board of each of the three institutions; informed consent was not required. The study included 17 hematopoietic stem cell transplant recipients with proved pulmonary candidiasis. Histopathologic specimens were acquired at transbronchial biopsy (n = 8), open lung biopsy (n = 6), and autopsy (n = 3). The patients included seven men and 10 women (age range, 20-62 years; mean age, 37 years). The thin-section CT scans were retrospectively reviewed by two thoracic radiologists for the presence, appearance, and distribution of parenchymal abnormalities. RESULTS: Multiple nodules were present in 15 (88%) patients, including centrilobular nodules and tree-in-bud pattern in seven (41%) patients. Nodules were bilateral in 12 patients and unilateral in three. An associated halo of ground-glass opacity was identified in five (33%) patients. Nodules were the only CT finding in five patients (29%). Areas of air-space consolidation were identified in 11 (65%) patients. Areas of ground-glass opacity were seen in six (35%) of 17 patients and were always associated with other abnormalities. Other less common CT findings included pleural effusion (n = 3), thickening of the bronchial walls (n = 2), and cavitation (n = 1). CONCLUSION: The most common thin-section CT findings of pulmonary candidiasis in hematopoietic stem cell transplant patients are multiple bilateral nodular opacities often associated with areas of consolidation.     

Rhodococcus equi pneumonia in AIDS: high-resolution CT findings in five patients

The aim of this study was to describe the high-resolution CT scan findings in five patients with AIDS and pulmonary infection due to Rhodococcus equi. The study included five patients with AIDS and proven R. equi infection. The CT scans were reviewed by two observers. The patients included four men and one woman ranging from 39 years to 49 years in age (mean 42 years). The findings included areas of consolidation (n=5) with single (n=1) or multiple cavitation (n=4), ground-glass opacities (n=5), centrilobular nodules (n=3), small centrilobular nodular opacities (n=3) and "tree in bud" opacities (n=3). None of the patients had pleural effusion or lymph node enlargement. The most common high-resolution CT manifestations of R. equi infection consist of areas of consolidation with cavitation, ground-glass opacities, nodules and a tree-in-bud pattern.     

High-resolution CT findings of severe acute respiratory syndrome at presentation and after admission

OBJECTIVE: The aim of this study was to assess the high-resolution CT (HRCT) findings at presentation and after hospital admission in patients with severe acute respiratory syndrome (SARS). MATERIALS AND METHODS: We reviewed the HRCT findings at presentation (n = 12) and after hospital admission (n = 25) of 29 patients with SARS and compared the HRCT findings with the radiographic findings. HRCT scans were obtained using 1-mm (n = 28) or 2-mm (n = 1) collimation. The radiographs and HRCT scans were reviewed independently by two observers who reached a decision by consensus. RESULTS: All patients had abnormal findings on HRCT at presentation. Eight of these 12 patients had normal findings on radiographs. The predominant HRCT findings at presentation consisted of unilateral (n = 6) or bilateral (n = 2) ground-glass opacities or focal unilateral (n = 2) or bilateral (n = 2) areas of consolidation. All patients showed progression of disease on follow-up. The predominant HRCT findings on follow-up CT scans consisted of unilateral (n = 2) or bilateral ground-glass opacities (n = 13), unilateral (n = 2) or bilateral consolidation (n = 5), or a mixed bilateral pattern of ground-glass attenuation, consolidation, and reticulation (n = 3). Reticulation with associated architectural distortion and mild traction bronchiectasis was present in eight patients. CONCLUSION: HRCT can show parenchymal abnormalities in patients with SARS who have normal findings on radiographs at presentation. Follow-up CT scans obtained in hospitalized patients show findings consistent with fibrosis in a small percentage of patients.     

"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.     

白血病患者骨髓移植术后肺部并发症的CT诊断

目的探讨白血病患者骨髓移植术后肺部并发症的CT诊断。方法对30例白血病患者骨髓移植术后肺部并发症的CT表现进行回顾性分析。结果巨细胞病毒性肺炎可以表现为弥漫性实变、多发结节、毛玻璃改变、多发小片状影,以弥漫性实变为最多见(37.5%,3/8);真菌性肺炎主要表现为单发球形病灶(50.0%,4/8),其中3例病灶周围可见毛玻璃密度影;细菌性肺炎主要表现为单发片状影(50%,1/2);急性呼吸窘迫综合征(ARDS)主要表现为弥漫性实变(66.7%,2/3);肺水肿主要表现为支气管血管束增粗或网格状改变(66.7%,2/3);药物毒性反应可表现为弥漫性实变(50.0%,1/2)或网格状改变(50.0%,1/2);细支气管闭塞并机化性肺炎气管炎(BOOP)表现为多发结节状改变(50.0%,1/2)或毛玻璃密度改变(50.0%,1/2)。移植后3周内发生率最高的为真菌感染,移植后3~14周发生率最高的为巨细胞病毒性肺炎,移植后14周以后病例较少,主要为BOOP。结论综合分析CT表现对血病患者骨髓移植术后肺部并发症的诊断有较高价值。     

Adenovirus pneumonia in adults: radiographic and high-resolution CT findings in five patients

OBJECTIVE: The purpose of this study was to describe the radiographic and high-resolution CT (HRCT) findings of adenovirus pneumonia in five patients. CONCLUSION: Adenovirus pneumonia in adults appears as bilateral patchy parenchymal opacities on chest radiographs and as bilateral ground-glass opacities with a random distribution with or without consolidation on HRCT images. These findings, however, are not specific for adenovirus pneumonia.     

High-resolution CT findings of diffuse bronchioloalveolar carcinoma in 38 patients

OBJECTIVE: The purpose of this study was to analyze the high-resolution CT features of diffuse bronchioloalveolar carcinoma and determine the useful findings in differential diagnosis. MATERIALS AND METHODS: High-resolution CT scans of 38 patients with pathologically proven diffuse bronchioloalveolar carcinoma were reviewed. Sequential CT scans were obtained in 15 patients. The high-resolution CT findings were compared with those of eosinophilic pneumonia (n = 22), multiple pulmonary metastases (n = 12), and tuberculosis (bronchogenic: n = 22; miliary: n = 12). RESULTS: High-resolution CT findings of diffuse bronchioloalveolar carcinoma included ground-glass opacity (n = 29), consolidation (n = 29), nodules (n = 28), centrilobular nodules (n = 26), peripheral distribution (n = 19), and air bronchogram (n = 18). According to the major features, high-resolution CT findings of diffuse bronchioloalveolar carcinoma could be classified into three patterns: predominantly ground-glass (n = 4), consolidative (n = 22), and multinodular (n = 12). Most patients with diffuse bronchioloalveolar carcinoma had a mixture of these findings. The frequency of findings of diffuse bronchioloalveolar carcinoma on high-resolution CT was not different from that of tuberculosis, but the predominant distribution of the nodules and areas of ground-glass attenuation differed between the two. Difference in distribution between bronchioloalveolar carcinoma and bronchogenic tuberculosis included ground-glass opacity remote from the consolidation and a lower lung predominance. CONCLUSION: Although these high-resolution CT findings are not specific, the combination of consolidation and nodules and the coexistence of centrilobular nodules and remote areas of ground-glass attenuation are characteristic of diffuse bronchioloalveolar carcinoma.     

闭塞性细支气管炎伴机化性肺炎的高分辨CT表现

目的探讨闭塞性细支气管炎伴机化性肺炎的高分辨CT表现,并与慢性嗜酸性肺炎和寻常型间质性肺炎进行鉴别。方法结合相关文献回顾性分析12例闭塞性细支气管炎伴机化性肺炎高分辨CT表现。结果12例闭塞性细支气管炎伴机化性肺炎的高分辨CT表现如下:(1)肺内多发斑片状肺实变影和磨玻璃影(n=8),其中肺实变影中见支气管充气征(n=5)。(2)肺内多发小结节影和不规则线状影(n=7)。(3)肺内多发斑片状肺实变影和磨玻璃影伴小结节影和不规则线状影(n=3)。(4)细支气管扩张、壁增厚伴周围肺实变影(n=6)。(5)肺内肺实变影和磨玻璃影呈游走性(n=3)。结论高分辨CT可以更好地显示闭塞性细支气管炎伴机化性肺炎的病理改变,并使其能与慢性嗜酸性肺炎和寻常型间质性肺炎在影像上进行鉴别,也为纤维支气管镜下肺活检提供准确的定位。     

Lung diseases in patients with common variable immunodeficiency: chest radiographic, and computed tomographic findings

OBJECTIVE: To evaluate chest radiographic and computed tomographic (CT) findings of lung disease related to common variable immunodeficiency. METHODS: Thirty-five chest radiographs and 30 CT scans of 46 patients were assessed. Lung parenchymal abnormalities that were evaluated included airspace consolidation, ground-glass attenuation, nodules, bronchiectasis, and air trapping. RESULTS: On CT, ground-glass attenuation and nodules were the most frequent findings, observed in 60% (n = 18/30) and 83% (n = 25/30), respectively. Three major CT patterns were identified: airway disease (n = 13), nodules (n = 8), and parenchymal opacification (n = 6). All 13 patients with airway disease showed centrilobular opacities. One patient with peribronchial nodules showed lymphoid interstitial pneumonia, and 1 with randomly distributed nodules showed noncaseating granulomas. Patients with a CT pattern of parenchymal opacification showed lower lung predominance; surgical biopsies showed organizing pneumonia in 1 patient and lymphoid interstitial pneumonia with nonnecrotizing granulomas in another. CONCLUSIONS: Common variable immunodeficiency is associated with 3 major CT patterns: airway disease, nodules, and parenchymal opacification.     

Squalene-induced extrinsic lipoid pneumonia: serial radiologic findings in nine patients.

PURPOSE: The purpose of this work was to demonstrate the initial and follow-up radiologic findings of squalene-induced extrinsic lipoid pneumonia. METHOD: Follow-up chest radiographs (n = 9) and high-resolution CT scans (n = 3) as well as initial radiographs (n = 9) and CT scans (n = 8) were obtained in nine patients with squalene-induced extrinsic lipoid pneumonia. The serial radiologic findings were analyzed retrospectively by three chest radiologists, focusing on the pattern and distribution of parenchymal abnormalities. RESULTS: The most frequent pattern of parenchymal abnormalities on chest radiograph was areas of ground-glass opacity (n = 9, bilateral 6), followed by consolidation (n = 7, bilateral 3) and poorly defined small nodules (n = 4, bilateral 2). The abnormalities were distributed in the right lower lung (n = 9), left lower lung (n = 6), and right middle lung (n = 6) zones. Initial CT scans (n = 8) demonstrated bilateral areas of ground-glass attenuation (n = 8), poorly defined centrilobular nodules (n = 8), crazy paving (n = 6), and consolidation (n = 3). The abnormalities were distributed in the right middle lobe (n = 8) and in both lower lobes (n = 5). Follow-up chest radiograph (n = 9) showed complete disappearance (n = 2) and decrease (n = 7) in the extent of the parenchymal abnormalities. Follow-up CT scans (n = 3) demonstrated decrease (n = 2) and no change (n = 1) in the extent of the abnormalities. CONCLUSION: Squalene-induced extrinsic lipoid pneumonia most commonly appears as areas of ground-glass attenuation mixed with poorly defined centrilobular nodules and crazy paving on CT, being distributed mainly in the right middle and both lower lobes. The lesions are indolent and remain after cessation of squalene ingestion.     

Human metapneumovirus infection in hematopoietic stem cell transplant recipients: high-resolution computed tomography findings

PURPOSE: To review the high-resolution computed tomography (CT) findings in hematopoietic stem cell transplant (HCT) recipients who had proven human metapneumovirus (HMPV) pneumonia. MATERIALS AND METHODS: The study included 5 HCT recipients who had proven HMPV pneumonia. The patients included 4 men and 1 woman ranging in age from 23 to 58 years (mean age = 42 years). The CT scans were assessed for the presence, appearance, size, and distribution of parenchymal abnormalities. RESULTS: Human metapneumovirus was isolated in all 5 patients in this series. None of these patients had any other infectious organism identified in cultures or bronchoalveolar lavage. The predominant CT findings were bilateral abnormalities in all patients, consisting primarily of a mixture of patterns, including, most commonly, ground-glass attenuation and nodular opacities. Areas of ground-glass opacification had no zonal predominance and were bilateral, asymmetric, and patchily distributed. Multiple nodules were identified in 4 (80%) of 5 patients. Nodules were multiple; less than 5 nodules were identified in 1 case, and 5 to 10 nodules were identified in 3 cases. All nodules in all cases were less than 10 mm in diameter. Areas of air-space consolidation were identified in 2 (40%) patients. All patients were available for follow-up; lesions improved in 4 patients. CONCLUSION: The thin-section CT manifestations of HMPV pneumonia usually consist of a mixture of patterns, including, most commonly, ground-glass attenuation and nodular opacities.     

Chronic pulmonary paracoccidioidomycosis (South American blastomycosis): high-resolution CT findings in 41 patients.

OBJECTIVE: To assess the pulmonary parenchymal findings on high-resolution CT in 41 patients with the chronic form of paracoccidioidomycosis (South American blastomycosis). SUBJECTS AND METHODS: The study included 41 consecutive patients in whom chronic paracoccidioidomycosis had been proven. All patients underwent high-resolution CT (1-mm collimation, high-spatial-frequency reconstruction algorithm) at 12 equally spaced intervals through the chest. The images were analyzed by two radiologists, and each final decision was reached by consensus. RESULTS: Thirty-eight (93%) of the 41 patients had CT scans with abnormal findings. The findings included interlobular septal thickening in 36 patients (88%), 1-25 mm diameter nodules in 34 (83%), peribronchovascular interstitial thickening in 32 (78%), centrilobular opacities in 26 (63%), intralobular lines in 24 (59%), ground-glass opacities in 14 (34%), cavitation in seven (17%), air-space consolidation in five (12%), traction bronchiectasis in 34 (83%), and paracicatricial emphysema in 28 (68%). In approximately 90% of patients, the abnormalities were bilateral and symmetrical and involved all lung zones. CONCLUSION: High-resolution CT findings of paracoccidioidomycosis consist predominantly of interstitial abnormalities and nodules associated with traction bronchiectasis and paracicatricial emphysema in a bilaterally symmetrical distribution.