Diffuse micronodular lung disease: HRCT and pathologic findings

Imaging recommendations and algorithms for pediatric tuberculosis: part 1-thoracic tuberculosis

Tuberculosis (TB) remains a global health problem and is the second leading cause of death from a single infectious agent, behind the novel coronavirus disease of 2019. Children are amongst the most vulnerable groups affected by TB, and imaging manifestations are different in children when compared to adults. TB primarily involves the lungs and mediastinal lymph nodes. Clinical history, physical examination, laboratory examinations and various medical imaging tools are combined to establish the diagnosis. Even though chest radiography is the accepted initial radiological imaging modality for the evaluation of children with TB, this paper, the first of two parts, aims to discuss the advantages and limitations of the various medical imaging modalities and to provide recommendations on which is most appropriate for the initial diagnosis and assessment of possible complications of pulmonary TB in children. Practical, evidence-based imaging algorithms are also presented.

Miliary tuberculosis in an immune-competent Bangladeshi man-A case report

Miliary tuberculosis is a disseminated and active form of tuberculosis caused by Mycobacterium tuberculosis. It frequently affects immunocompromised patients. However, immune-competent hosts are reported rarely. Herein, we reported a case of miliary tuberculosis of a 40-year-old immune-competent Bangladeshi man presented with pyrexia of unknown origin.

High-Resolution Computed Tomography of Nonfibrotic Interstitial Lung Disease

Nonfibrotic interstitial lung diseases include a heterogeneous group of conditions that can result in various patterns of lung involvement. When approaching the computed tomographic (CT) scan of a patient with a suspected or known interstitial lung disease, the use of the appropriate radiological terms and a systematic, structured approach to the interpretation of the imaging findings are essential to reach a confident diagnosis or to limit the list of differentials to few possibilities. The large number of conditions that cause nonfibrotic interstitial lung diseases prevents a thorough discussion of all these entities. Therefore, this article will focus on the most common chronic lung diseases that can cause these CT findings. A pattern-based approach is used, with a discussion of nodular pattern, consolidation, crazy paving, ground-glass opacities, septal thickening, and calcifications. The different clinical conditions will be described based on their predominant pattern, with particular attention to findings that can help in the differential diagnosis.

The Atypical Manifestation of Pulmonary Tuberculosis in Patients with Bronchial Anthracofibrosis

It has been stated that bronchial anthracofibrosis (BAF) has an important relationship with pulmonary tuberculosis (TB), and the coexistence of TB and BAF is high. The purpose of this study was to compare the differences in computed tomography (CT) characteristics of pulmonary TB according to the presence of underlying BAF. Total of 202 consecutive patients who were diagnosed with pulmonary TB and underwent bronchoscopy and CT in our institution were retrospectively reviewed. We classified the patients into two groups according to the presence of BAF and compared the clinicoradiological findings between the two groups (anthracofibrosis group vs. nonanthracofibrosis group). Elderly and female patients were significantly higher in anthracofibrosis group (mean age 79 ± 7 (64−94) vs. 56 ± 17 (16−95), p < 0.001; female 89% vs. 29%, p < 0.001). The frequency of internal low-density area or focal contour bulge within atelectasis (64% vs. 1%, p < 0.001), lower lobe predominance (43% vs. 9%, p < 0.001), endobronchial involvement (46% vs. 15%, p < 0.001), and lymphadenopathy (57% vs. 28%, p = 0.002) were significantly higher in anthracofibrosis group. In contrast, the anthracofibrosis group showed lower frequency of upper lobe predominance (32% vs. 81%, p < 0.001) and cavitation (14% vs. 51%, p = 0.001). In conclusion, being aware of these atypical manifestations of pulmonary TB in the presence of BAF will be of great help in early detection of TB.

Micronodular lung disease on high-resolution CT: patterns and differential diagnosis

With the advent of high-resolution computed tomography (HRCT), micronodular lung disease is a routinely encountered pathology in thoracic imaging. This article will review how to differentiate the three main micronodular patterns and review the differential diagnosis for each. Differential diagnosis of micronodular lung disease may be extensive, but by identifying the pattern and using additional clues, such as distribution, additional imaging findings, and clinical history, a radiologist can make an accurate diagnosis. First, three micronodular patterns - centrilobular, peri-lymphatic, and random - can be identified by using a simple algorithm based on the location of nodules. This algorithm requires understanding of the anatomy and function of the secondary pulmonary lobule. Each micronodular pattern offers a unique differential diagnosis. Centrilobular nodules can be seen with inflammatory, infectious, or vascular aetiologies; peri-lymphatic nodules with sarcoidosis and lymphangitic carcinomatosis; and random nodules with haematogenous metastases or infections.

Nodular distribution pattern on chest computed tomography (CT) in patients diagnosed with nontuberculous mycobacteria (NTM) infections

BACKGROUND

This study evaluated the prevalence of spreading pathways in nontuberculous mycobacteria (NTM) pulmonary infections according to nodular distribution patterns seen on chest computed tomography (CT).

METHODS

This study included 63 patients diagnosed with NTM lung infections who underwent CT at our institution. A retrospective analysis of CT images focused on the presence and distribution of nodules, presence of intrathoracic lymphadenopathy and the predominant side of infection in the lungs. The findings were classified into five groups; centrilobular (bronchogenic spread), perilymphatic (lymphangitic spread), random (hematogenous spread), combined pattern and no nodules present. The groups were then compared according to other CT findings.

RESULTS

Among 51 (81%) patients identified with a nodular pattern on chest CT, 25 (39.8%) presented with centrilobular, 7 (11.1%) with perilymphatic, 6 (9.5%) with random and 13 (20.6%) with combined nodular patterns but located in different areas of the lungs. The right side of the lungs was predominant in 38 cases (60.3%). Intrathoracic lymphadenopathy was evident in 20 patients (31.7%). Significant differences in distributions of nodular patterns were seen in patients infected with Mycoplasma avium complex (MAC) associated with centrilobular pattern (p = 0.0019) and M. fortuitum associated with random pattern (p = 0.0004). Some of the findings were related to perilymphatic nodules between other isolated species of NTM (p = 0.0379).

CONCLUSION

The results of this study showed a high proportion of perilymphatic nodules and right-sided predominance in the upper lobe, which, combined with intrathoracic lymphadenopathy is highly suggestive of the lymphangitic spread of lung NTM infections.

Uncommon thoracic manifestations from extrapulmonary tumors: Computed tomography evaluation - Pictorial review

Although metastasis can occur at a variety of sites, pulmonary involvement is common in patients with cancer. Depending on the source and type of tumor, pulmonary metastases present with a wide range of radiologic appearances. Hematogenous dissemination through the pulmonary arteries to the pulmonary capillary network is the most common form of spread in pulmonary metastases. However, they may also reach the lung via lymphatic dissemination, secondary airway involvement, vessel tumor embolism, and direct chest invasion. In the evaluation of patients with known extrathoracic tumors, CT is the state-of-the-art imaging modality for detecting and characterize pulmonary metastases as well as to predict resectability. Although CT limitations are well known, knowledge of growth rates of various tumors and understanding the pattern of spread may be helpful clues in suggesting and even establish the specific diagnosis. The purpose of this pictorial review is to discuss the imaging appearances of different patterns of intrathoracic tumoral dissemination.

Sarcoidosis: A Diagnosis of Exclusion

OBJECTIVE. This article will review the typical and atypical imaging features of sarcoidosis, identify entities that may be mistaken for sarcoidosis, and discuss patterns and clinical scenarios that suggest an alternative diagnosis. CONCLUSION. Radiologists must be familiar with the characteristic findings in sarcoidosis and be attentive to situations that suggest alternative diagnoses. The radiologist plays a major role in prompt diagnosis and one that may help reduce patient morbidity and mortality.

Imaging of Pulmonary Infections

Pulmonary infections have always been a cause of high morbidity and mortality, particularly in the pediatric and geriatric population and in immunocompromised hosts [1]. Pulmonary infections have various etiologies and have variegated patterns on radiographs and computed tomography (CT). Imaging plays an important role in the initial diagnosis and follow-up of various lung infections. Radiographs can be normal or non-specific during the initial evaluation, and CT findings may be more definitive. CT not only helps with the diagnosis but can also aid in management by guiding the diagnostic and therapeutic procedure. The pulmonary infections spread by direct or indirect contact with the infected host, droplet transmission, or an airborne spread. In rare cases, some infections can also be transmitted by vectors, namely, insect or animal hosts, and rarely by direct invasion from nearby infected organs. Pulmonary infections may have typical imaging patterns and distribution based on the mode of spread. There are a number of well-described imaging patterns of alveolar infections. The localization and morphological features on imaging may help in the diagnosis of infection and identification of mode of infection and, in certain cases, the microorganism responsible for the infection.

Miliary Tuberculosis

Miliary tuberculosis (TB) results from a massive lymphohematogenous dissemination of Mycobacterium tuberculosis bacilli and is characterized by tiny tubercles evident on gross pathology resembling millet seeds in size and appearance. The global HIV/AIDS pandemic and widespread use of immunosuppressive drugs and biologicals have altered the epidemiology of miliary TB. Considered to be predominantly a disease of infants and children in the pre-antibiotic era, miliary TB is increasingly being encountered in adults as well. The clinical manifestations of miliary TB are protean and nonspecific. Atypical clinical presentation often delays the diagnosis. Clinicians, therefore, should have a low threshold for suspecting miliary TB. Focused, systematic physical examination helps in identifying the organ system(s) involved, particularly early in TB meningitis, as this has therapeutic significance. Fundus examination for detecting choroid tubercles offers a valuable clinical clue for early diagnosis, as their presence is pathognomonic of miliary TB. Imaging modalities help in recognizing the miliary pattern, defining the extent of organ system involvement. Examination of sputum, body fluids, image-guided fine-needle aspiration cytology or biopsy from various organ sites, needle biopsy of the liver, bone marrow aspiration, and biopsy should be done to confirm the diagnosis. Cytopathological, histopathological, and molecular testing (e.g., Xpert MTB/RIF and line probe assay), mycobacterial culture, and drug susceptibility testing must be carried out as appropriate and feasible. Miliary TB is uniformly fatal if untreated; therefore, early initiation of specific anti-TB treatment can be lifesaving. Monitoring for complications, such as acute kidney injury, air leak syndromes, acute respiratory distress syndrome, adverse drug reactions such as drug-induced liver injury, and drug-drug interactions (especially in patients coinfected with HIV/AIDS), is warranted.

Miliary tuberculosis: A new look at an old foe

Miliary tuberculosis (TB), is a fatal form of disseminated TB characterized by tiny tubercles evident on gross pathology similar to innumerable millet seeds in size and appearance. Global HIV/AIDS pandemic and increasing use of immunosuppressive drugs have altered the epidemiology of miliary TB. Keeping in mind its protean manifestations, clinicians should have a low threshold for suspecting miliary TB. Careful physical examination should focus on identifying organ system involvement early, particularly TB meningitis, as this has therapeutic significance. Fundus examination for detecting choroid tubercles can help in early diagnosis as their presence is pathognomonic of miliary TB. Imaging modalities help in recognizing the miliary pattern, define the extent of organ system involvement and facilitate image guided fine-needle aspiration cytology or biopsy from various organ sites. Sputum or BAL fluid examination, pleural, pericardial, peritoneal fluid and cerebrospinal fluid studies, fine needle aspiration cytology or biopsy of the lymph nodes, needle biopsy of the liver, bone marrow aspiration and biopsy, testing of body fluids must be carried out. GeneXpert MTB/RIF, line probe assay, mycobacterial culture and drug-susceptibility testing must be carried out as appropriate and feasible. Treatment of miliary TB should be started at the earliest as this can be life saving. Response to first-line anti-TB drugs is good. Screening and monitoring for complications like acute respiratory distress syndrome (ARDS), adverse drug reactions like drug-induced liver injury, drug-drug interactions, especially in patients co-infected with HIV/AIDS, are warranted. Sparse data are available from randomized controlled trials regarding optimum regimen and duration of anti-TB treatment.

Clinicoradiologic evidence of pulmonary lymphatic spread in adult patients with tuberculosis

OBJECTIVE

The purpose of this study is to evaluate the prevalence and clinicoradiologic characteristics of pulmonary tuberculosis with lymphatic involvement.

MATERIALS AND METHODS

A total of 126 adults with active tuberculosis who underwent CT were enrolled. A retrospective investigation of CT images focused on the presence of perilymphatic micronodules, as well as other CT features of active tuberculosis. We selected two groups of patients with micronodules according to distribution (perilymphatic vs centrilobular). We compared clinical and CT findings between the two groups.

RESULTS

Fifteen patients were excluded because of coexisting pulmonary disease. Among 111 patients, the prevalence of perilymphatic micronodules, galaxy or cluster signs, and interlobular septal thickening was 64 (58%), 18 (16%), and 30 (27%), respectively. Of 106 patients with micronodules, 37 and 40 were classified into the perilymphatic and centrilobular groups, respectively. Compared with the centrilobular group, the perilymphatic group had statistically significantly lower frequencies of positive acid-fast bacilli smears (32% vs 70%), consolidation (70% vs 98%), and cavitation (30% vs 60%). However, frequencies of interlobular septal thickening (41% vs 18%), galaxy or cluster signs (30% vs 0%), and pleural effusion (43% vs 20%) were statistically significantly higher in the perilymphatic group.

CONCLUSION

CT findings representing pulmonary perilymphatic involvement are relatively common in adults with tuberculosis. These findings may represent lymphatic spread of tuberculosis and provide an explanation for the unusual CT features of pulmonary tuberculosis mimicking sarcoidosis and the low detection of Mycobacterium tuberculosis in patients with micronodules.

High resolution computed tomography findings in smear-negative pulmonary tuberculosis patients according to their culture status

OBJECTIVE

The aim of this study was to assess the clinical features and high resolution computed tomography (HRCT) findings in smear-negative pulmonary tuberculosis (PTB) and to evaluate the correlation between these parameters and the culture results.

METHODS

We retrospectively studied 78 active smear-negative PTB patients. They were divided into two groups according to their culture results. The HRCT findings and clinical features at the beginning of the antituberculosis treatment were reviewed.

RESULTS

The mean age was 22.48±3.18 years. Micronodules (87%), large nodules (63%) and centrilobular nodules (62%) were the most common HRCT findings. HRCT findings were observed in the right upper (72%), left upper (56%), right lower (32%), and left lower lobes (29%). Cough (37%) and chest pain (32%) were the most frequent symptoms at presentation.

CONCLUSIONS

There were no significant differences in the HRCT findings and clinical features between the two groups. Thus, in cases of smear-negative and culture-negative PTB, the patient with compatible clinical and radiological features should be considered for tuberculosis treatment.

Features and prognostic impact of distant metastasis in patients with stage IV lung adenocarcinoma harboring EGFR mutations: importance of bone metastasis

Mutated epidermal growth factor receptor (EGFR) and signaling pathways were associated with multiple brain and intra-pulmonary metastases, oncogenic progression and metastasis. However, features of metastasis to other organs and the independent prognostic influence of metastatic lesions were not elucidated in patients with lung cancer harboring EGFR mutations. Between January 2007 and April 2012, we treated 277 patients diagnosed with stage IV lung adenocarcinoma. Studied were 246 patients with available tumor EGFR mutation data who also underwent radiographic evaluation of lung, abdominal, brain, and bone metastases. The EGFR mutated group (N = 98) had significantly more metastatic lesions in the brain and bone than the wild-type group (N = 148): brain, 3 (1-93) versus 2 (1-32) median (range), P = 0.023; bone, 3 (1-43) versus 2 (1-27), P = 0.035, respectively. In addition, EGFR mutations were significantly more frequent in patients with multiple than non-multiple lung metastases (24/40 vs. 12/42, P = 0.004). Multivariate analysis showed that bone metastasis was a significant independent negative predictive factor of overall survival (OS) in patients with mutated [hazard ratio (HR) 2.04; 95 % confidence interval (CI) 1.17-3.64; P = 0.011] and wild-type EGFR (HR 2.09; 95 % CI 1.37-3.20; P < 0.001). In conclusion, patients with mutated EGFR had more lung, brain, and bone metastases, and bone metastasis was an independent negative predictor of OS.

Lung infections: the radiologist's perspective

Imaging plays a key role in lung infections. A CT scan must be carried out when there is a strong clinical suspicion of pneumonia that is accompanied by normal, ambiguous, or nonspecific radiography, a scenario that occurs most commonly in immunocompromised patients. CT allows clinicians to detect associated abnormalities or an underlying condition and it can guide bronchoalveolar lavage or a percutaneous or transbronchial lung biopsy. An organism can vary in how it is expressed depending on the extent to which the patient is immunocompromised. This is seen in tuberculosis in patients with AIDS. The infective agents vary with the type of immune deficiency and some infections can quickly become life-threatening. Clinicians should be aware of the complex radiological spectrum of pulmonary aspergillosis, given that this diagnosis must be considered in specific settings.

Association of diffuse, random pulmonary metastases, including miliary metastases, with epidermal growth factor receptor mutations in lung adenocarcinoma

BACKGROUND

Although the association of multiple pulmonary metastases, and particularly miliary metastases, with response to gefitinib treatment in patients with nonsmall cell lung cancer has been reported, the association of miliary pulmonary metastases with epidermal growth factor receptor gene (EGFR) mutations remains unclear.

METHODS

The authors retrospectively investigated the association of diffuse, random pulmonary metastases in patients with lung adenocarcinoma. The study included 163 Japanese patients who had unresectable, advanced lung adenocarcinoma diagnosed between April 2003 and March 2010. Computed tomography scans that were obtained at the time of diagnosis were analyzed by 2 investigators. For the purposes of this study, diffuse, random pulmonary metastases were defined as multiple nodules (n = 50; ≤ 3 cm in greatest dimension) distributed diffusely and randomly throughout the lungs.

RESULTS

Of 163 patients, 55 had pulmonary metastases, and EGFR mutations were detected in 22 of those 55 patients. The mutations were identified preferentially among women (P = .15) and were identified significantly among patients who had a smoking history of < 10 pack-years (P = .0057). Diffuse, random pulmonary metastases were identified in 11 of 22 patients who had EGFR mutations and in 4 of 33 patients who had the wild-type EGFR (P = .0043). On the basis of multivariate analyses, EGFR mutations were associated independently with a smoking history of < 10 pack-years (P = .026) and with diffuse, random pulmonary metastases (P = .012).

CONCLUSIONS

When patients with lung adenocarcinomas who had EGFR mutations developed pulmonary metastases, they tended to be diffuse and random, including military metastases. However, such metastases were much less common in patients who had lung adenocarcinomas with wild-type EGFR.

Imaging of pulmonary vasculitis

The presence of pulmonary vasculitis can be suggested by a clinical presentation that includes diffuse pulmonary hemorrhage, acute glomerulonephritis, chronic refractory sinusitis or rhinorrhea, imaging findings of nodules or cavities, mononeuritis multiplex, multisystemic disease, and palpable purpura. Serologic tests, including the use of cytoplasmic antineutrophil cytoplasmic antibody (ANCA) and perinuclear ANCA, are performed for the differential diagnosis of the diseases. A positive cytoplasmic ANCA test result is specific enough to make a diagnosis of ANCA-associated granulomatous vasculitis if the clinical features are typical. Perinuclear ANCA positivity raises the possibility of Churg-Strauss syndrome or microscopic polyangiitis. Imaging findings of pulmonary vasculitis are diverse and often poorly specific. The use of a pattern-based approach to the imaging findings may help narrow the differential diagnosis of various pulmonary vasculitides. Integration of clinical, laboratory, and imaging findings is mandatory for making a reasonably specific diagnosis.

[HRCT of the lung: nodular pattern: anatomy and differential diagnosis]

Since the spectrum of differential diagnoses is wide, the interpretation of a nodular pattern in lung lesions detected on CT is a frequent problem. Number, size, localization, and morphology (shape, density, margins) contribute to evaluating the most probable differential diagnosis. "Classical" high resolution CT or high resolution image reconstructions from multiple row detector CT helical acquisitions achieve a detail resolution that makes it possible to distinguish findings by their typical predominance in certain anatomical compartments of the lung. The position of bronchial, vascular and lymphatic structures can be determined down to the secondary pulmonary lobule, the smallest subunit of the lung to be separated by septa of connective tissue. Based on this, a centrilobular predominance of nodules, i.e. with a tree-in-bud pattern, is a frequent sign of bronchiolitis. Perilymphatic predominance in the periphery of the lobules is associated with sarcoidosis or lymphangitic spread of cancer. Random distribution of nodules is interpreted as a sign of hematogenic spread of disease. Hence the subtle interpretation of specific findings on HRCT can contribute substantially to clinical decision making, although these signs may not always replace biopsy and histologic workup.

Frequency and predictors of miliary tuberculosis in patients with miliary pulmonary nodules in South Korea: a retrospective cohort study

Background

Miliary pulmonary nodules are commonly caused by various infections and cancers. We sought to identify the relative frequencies of various aetiologies and the clinical and radiographic predictors of miliary tuberculosis (TB) in patients with miliary pulmonary nodules.

Methods

We performed a retrospective cohort study of patients who presented with micronodules occupying more than two-thirds of the lung volume, based on computed tomography (CT) of the chest, between November 2001 and April 2007, in a tertiary referral hospital in South Korea.

Results

We analyzed 76 patients with miliary pulmonary nodules. Their median age was 52 years and 38 (50%) were males; 18 patients (24%) had a previous or current malignancy and five (7%) had a history of TB. The most common diagnoses of miliary nodules were miliary TB (41 patients, 54%) and miliary metastasis of malignancies (20 patients, 26%). Multivariate analysis revealed that age ≤30 years, HIV infection, corticosteroid use, bronchogenic spread of lesions, and ground-glass opacities occupying >25% of total lung volume increased the probability of miliary TB. However, a history of malignancy decreased the probability of miliary TB.

Conclusion

Miliary TB accounted for approximately half of all causes of miliary pulmonary nodules. Young age, an immune-compromised state, and several clinical and radiographic characteristics increased the probability of miliary TB.

Multi slice computed tomography in the study of pulmonary metastases

PURPOSE

This study was undertaken to assess the performance of 16-slice computed tomography (MSCT) using Multi-Planar Reformatting (MPR), Maximum Intensity Projection (MIP) and Volume Rendering (VR) reconstructions to study pulmonary metastases.

MATERIALS AND METHODS

CT studies of 32 patients with pulmonary metastases were retrospectively reviewed. Images were assessed for the following parameters: number, size, location, distribution of the nodules and the presence of the "mass-vessel sign". These parameters were evaluated by two observers on axial-source images and on MPR, MIP and VR reconstructions. Sensitivity of each reconstruction and interobserver agreement were calculated.

RESULTS

Two-dimensional (2D) axial images and MIP and VR reconstructions exhibited 100% sensitivity for lesions >10 mm. For nodules 6-10 mm, sensitivity was 49%-55% for the 2D images, 90% for MIP and 80%-85% for VR reconstructions. For metastasis <or= 5 mm, sensitivity was 22% for 2D images, 87%-89% for MIP and 55%-58% for VR reconstructions. Coronal and sagittal MPR, MIP and VR did not improve the detection rate compared with the corresponding axial images. MIP and VR provided overlapping results in detecting the "mass-vessel sign".

CONCLUSIONS

MIP are the most sensitive reconstructions for detecting small pulmonary nodules.

Padrões tomográficos das doenças intersticiais pulmonares difusas com correlação clínica e patológica

A tomografia de alta resolução (TCAR) é a técnica de imagem radiológica que reflete mais de perto as alterações da estrutura pulmonar. Os vários achados tomográficos podem ser combinados para formar padrões típicos. Estes, conjuntamente com a distribuição anatômica dos achados, e com os dados clínicos, podem estreitar o diagnóstico das doenças intersticiais pulmonares difusas, e em vários casos sugerir o diagnóstico correto com alto grau de acurácia. Os padrões mais comuns das doenças intersticiais pulmonares difusas na TCAR são o nodular, linear e reticular, lesões císticas, opacidades em vidro fosco e consolidações. Este artigo revisa as correlações entre os padrões tomográficos na TCAR e os achados patológicos e resume as causas mais comuns e os métodos de investigação para se atingir um diagnóstico nas doenças pulmonares crônicas difusas mais comuns.

Pulmonary involvement in Churg-Strauss syndrome: an analysis of CT, clinical, and pathologic findings

We tried to assess retrospectively thin-section CT findings of Churg-Strauss syndrome (CSS) in 25 patients and to compare these findings with clinical and histopathologic findings. Of 25 patients, 19 (76%) had parenchymal abnormalities at CT; small nodules (n = 12; 63%), ground-glass opacity (n = 10; 53%), bronchial wall thickening (n = 10; 53%), and consolidation (n = 8; 42%). Parenchymal abnormalities (n = 19) were categorizable as an airway pattern in 11 and an airspace pattern in eight. Patients with an airway pattern (n = 5) had obstructive (n = 3) or combined (n = 2) PFT results, whereas those with an airspace pattern (n = 4) had restrictive (n = 3) or obstructive (n = 1) results. Parenchymal opacities at CT corresponded histologically to areas of eosinophilic pneumonia, necrotizing granulomas, and granulomatous vasculitis; small nodules to eosinophilic bronchiolitis and peribronchiolar vasculitis; and bronchial wall thickening to airway wall eosinophil and lymphocyte infiltration. Patients with airspace pattern responded more readily to treatment than those with airway pattern. CT shows lung parenchymal abnormalities in about three-quarters of CSS patients and these abnormalities can be categorized as airspace or airway patterns. This classification helps predict PFT data, underlying histopathology, and treatment response.

Radiological findings of mycobacterial diseases

The diagnosis and treatment of mycobacterial diseases are very important clinical issues. Among mycobacterial diseases, pulmonary tuberculosis remains an important cause of morbidity and mortality throughout the world. Pulmonary tuberculosis demonstrates a variety of clinical and radiological features. In addition, the prevalence of Mycobacterium avium complex (MAC) has increased, especially in elderly women without underlying diseases. Clinically, there is a significant difference between tuberculosis and atypical mycobacterium infection in terms of the infection control measures adopted and the choice of treatment. Therefore, it is very important to know the characteristic radiological findings of mycobacterial diseases. In the present review, key radiological points for diagnosing mycobacterial diseases are discussed.

Mycoplasma pneumoniae pneumonia: differential diagnosis by computerized tomography

OBJECTIVE AND BACKGROUND

This study was designed to clarify chest computerized tomography (CT) findings of Mycoplasma pneumoniae pneumonia facilitating differential diagnosis from CAP (community acquired pneumonia) caused by other organisms.

METHODS

We retrospectively reviewed the CT findings of 36 patients (median age 33 years, 15 males, 21 females) with serologically proven M. pneumoniae pneumonia and 52 patients (median age 61 years, 37 males, 15 females) suffering from CAP with no serological evidence of M. pneumoniae infection. The CT images were analyzed by experienced pulmonologists.

RESULTS

The most common finding in the M. pneumoniae pneumonia group was bronchial wall thickening, when we compared it with the CAP group (p<0.0001, Fisher's exact probability test). In the CAP group infected with other organisms, dense consolidations with air bronchograms were more frequent than any other findings (p=0.0279, chi-square test).

CONCLUSIONS

The diagnosis of M. pneumoniae pneumonia would appear to be reliable when we found bronchial wall thickening in the chest CT images.

Intravenous injection of pharmaceutical tablets presenting as multiple pulmonary nodules and declining pulmonary function in an adolescent with cystic fibrosis

Here we present the unusual case of an adolescent with cystic fibrosis presenting with declining pulmonary function and diffuse micronodular pulmonary disease. This case illustrates the radiographic and pathologic findings associated with the intravenous injection and pulmonary arterial embolization of insoluble pharmaceutical-tablet constituents. The number of first-time users reporting nonmedical use of prescription pain relievers is increasing dramatically, especially in adolescents. Recognition of both the diagnostic imaging features and histologic features on lung biopsy are critical steps for early diagnosis, intervention, and potential prevention of sudden death in these at-risk patients.

Imaging of Metastatic Disease to the Thorax

Tumor imaging is at the forefront of radiology technology and is the focus of most cutting edge research. Radiologic applications for imaging of metastases are applied to initial staging, restaging after neoadjuvant therapy, and follow-up surveillance after therapy for tumor recurrence. CT is the routine imaging choice in staging, restaging, and detection of recurrence. Fluorodeoxyglucose-positron emission tomography has evolved as an imaging modality that further improves staging as well as the detection of recurrent and metastatic disease.

Radiological manifestations of pulmonary tuberculosis

Pulmonary tuberculosis (TB) is a common worldwide lung infection. The radiological features show considerable variation, but in most cases they are characteristic enough to suggest the diagnosis. Classically, tuberculosis is divided into primary, common in childhood, and postprimary, usually presenting in adults. The most characteristic radiological feature in primary tuberculosis is lymphadenopathy. On enhanced CT, hilar and mediastinal nodes with a central hypodense area suggest the diagnosis. Cavitation is the hallmark of postprimary tuberculosis and appears in around half of patients. Patchy, poorly defined consolidation in the apical and posterior segments of the upper lobes, and in the superior segment of the lower lobe is also commonly observed. Several complications are associated with tuberculous infection, such as hematogenous dissemination (miliary tuberculosis) or extension to the pleura, resulting in pleural effusion. Late complications of tuberculosis comprise a heterogeneous group of processes including tuberculoma, bronchial stenosis bronchiectasis, broncholithiasis, aspergilloma, bronchoesophageal fistula and fibrosing mediastinitis. Radiology provides essential information for the management and follow up of these patients and is extremely valuable for monitoring complications.

Small-vessel diseases of the lung: CT-pathologic correlates

Diseases that primarily affect the small vessels of the lung are difficult to diagnose. Many conditions are characterized by involvement of small pulmonary vessels, and pathologically they can be conveniently divided into occluding and inflammatory types. The former, typified by chronic pulmonary thromboembolism and primary pulmonary hypertension, are relatively cryptic in terms of imaging. In contrast, inflammatory vasculitides, which often cause pulmonary hemorrhage and infarction, result in florid but nonspecific radiographic abnormalities. The spectrum of thin-section computed tomographic abnormalities encountered in the inflammatory vasculitides is wide: For example, in Wegener granulomatosis the pattern ranges from cavitating nodules to lobar consolidation to ground-glass opacity. This review highlights some of the less obvious imaging manifestations of occlusive and inflammatory diseases of the small pulmonary vessels.

Tuberculose pulmonar: achados na tomografia computadorizada de alta resolução do tórax em pacientes com doença em atividade comprovada bacteriologicamente

Objetivo: Descrever os achados em pacientes com tuberculose pulmonar em atividade na tomografia computadorizada de alta resolução e o padrão de distribuição das lesões pelo parênquima pulmonar. Casuística e método: Foram analisadas retrospectivamente as tomografias de alta resolução de 42 pacientes com diagnóstico bacteriológico de tuberculose pulmonar ou forte suspeita clínica, com posterior confirmação bacteriológica. Resultados: Os principais sinais sugestivos de atividade encontrados foram nódulos do espaço aéreo (83%), nódulos centrolobulares (74%), aspecto de árvore em brotamento (67%), cavitações (67%), espessamento das paredes brônquicas (55%), consolidações (48%), opacidade em vidro fosco (21%), e espessamento do interstício pulmonar (9%). Conclusão: A tomografia computadorizada de alta resolução do tórax pode sugerir fortemente atividade da doença, sendo particularmente útil nos pacientes com baciloscopias negativas e/ou radiografias indeterminadas, permitindo a instituição de tratamento adequado, antes mesmo do crescimento da micobactéria em meio de cultura.

Various diffuse infiltrative lung diseases: high resolution computed tomography appearances

High resolution CT (HRCT; 1-2 mm collimation scans reconstructed with a high spatial frequency algorithm) is an established technique for the evaluation of diffuse infiltrative lung diseases. For many of these diseases, the features shown on HRCT correlate well with the histopathological abnormalities. The purpose of this pictorial essay is to illustrate HRCT appearances in various diffuse infiltrative lung diseases.

Pulmonary involvement in mixed connective tissue disease: high-resolution CT findings in 41 patients

The objective of this study was to describe the pulmonary abnormalities on high-resolution computed tomography (CT) in patients with mixed connective tissue disease (MCTD). The study included 41 patients who met the diagnostic criteria for MCTD and showed abnormal findings on high-resolution CT. The presence, extent, and distribution of various high-resolution CT findings were evaluated. The predominant abnormalities included areas of ground-glass attenuation (n = 41), subpleural micronodules (n = 40), and nonseptal linear opacities (n = 32). Other common findings included peripheral predominance (n = 40), lower lobe predominance (n = 39), intralobular reticular opacities (n = 25), architectural distortion (n = 20), and traction bronchiectasis (n = 18). Less common findings included honeycombing, ill-defined centrilobular nodules, airspace consolidation, interlobular septal thickening, thickening of bronchovascular bundles, bronchial wall thickening, bronchiectasis, and emphysema. Pulmonary involvement of MCTD is characterized by the presence of ground-glass attenuation, nonseptal linear opacities, and peripheral and lower lobe predominance. Ill-defined centrilobular opacities were uncommonly seen.