Pulmonary tuberculosis: CT findings--early active disease and sequential change with antituberculous therapy

Idiopathic dendriform pulmonary ossification as the phenotype of interstitial lung abnormalities: CT-pathologic correlation and prevalence

BACKGROUND AND PURPOSE

Idiopathic dendriform pulmonary ossification (DPO) is mostly asymptomatic, and detected incidentally in lung CT. There have been no reports on the precise CT-pathologic correlation and the prevalence of idiopathic DPO. This study aimed to clarify the histological background and prevalence of idiopathic DPO.

MATERIALS AND METHODS

Sixteen patients with histologically confirmed idiopathic DPO (12 men and 4 women; mean age, 38.8 years; range 22-56 years) were identified in a nationwide epidemiological survey. Local HRCT findings of pre-biopsy examinations, such as branching, round, linear structures with or without high attenuation were compared side by side with histological findings. The attenuation of branching, round, and linear structures was classified into three-point levels on bone window images (width, 2500 HU; level, 500 HU). Furthermore, we collected continuous pulmonary CT images of 8111 cases for checking up metastasis from extrathoracic malignancy at a single institution, and evaluated the prevalence of interstitial lung abnormalities (ILAs) and DPO.

RESULTS

In all 16 cases, branching (n = 15, 93%), round (n = 5, 31%), or linear (n = 5, 31%) structures were identified, histologically corresponding to dendriform ossification and cicatricial organizing pneumonia (OP)/fibrosis. Histologically, ossification was confirmed in all the 16 patients. However, in two cases, a highly attenuated structure could not be detected on the pre-biopsy CT of the same area. Regarding the prevalence of idiopathic DPO, 283 (3.5%) of 8111 patients had ILAs, of which a total of 26 (0.3% of all cases, 9.2% of ILAs cases) had DPO.

CONCLUSION

Idiopathic DPO showed linear or branching structures with or without high attenuation on CT, corresponded to ossification, cicatricial OP/fibrosis. DPO was seen in 9.2% of ILAs cases. Idiopathic DPO is one of pathologic phenotypes of ILAs.

Long term management of people with post-tuberculosis lung disease

Post-tuberculosis lung disease (PTLD) is emerging as a significant area of global interest. As the number of patients surviving tuberculosis (TB) increases, the subsequent long-term repercussions have drawn increased attention due to their profound clinical and socioeconomic impacts. A primary obstacle to its comprehensive study has been its marked heterogeneity. The disease presents a spectrum of clinical manifestations which encompass tracheobronchial stenosis, bronchiectasis, granulomas with fibrosis, cavitation with associated aspergillosis, chronic pleural diseases, and small airway diseases-all persistent consequences of PTLD. The spectrum of symptoms a patient may experience varies based on the severity of the initial infection and the efficacy of the treatment received. As a result, the long-term management of PTLD necessitates a detailed and specific approach, addressing each manifestation individually-a tailored strategy. In the immediate aftermath (0-12 months after anti-TB chemotherapy), there should be an emphasis on monitoring for relapse, tracheobronchial stenosis, and smoking cessation. Subsequent management should focus on addressing hemoptysis, managing infection including aspergillosis, and TB-associated chronic obstructive pulmonary disease or restrictive lung function. There remains a vast expanse of knowledge to be discovered in PTLD. This review emphasizes the pressing need for comprehensive, consolidated guidelines for management of patients with PTLD.

Novel Insights into the Pathogenesis of Human Post-Primary Tuberculosis from Archival Material of the Pre-Antibiotic Era, 1931-1947

OBJECTIVES

Primary and post-primary tuberculosis (TB) are distinct entities. The aim of this study was to study the histopathology of primary and post-primary TB by using the unique human autopsy material from the pre-antibiotic era, 1931-1947.

MATERIAL AND METHODS

Autopsy data were collected from the autopsy journals, and the human tissue was collected from the pathology archives at the Department of Pathology, the Gades Institute.

RESULTS

Histological presentations of TB lesions showed great diversity within a single lung. Post-primary TB starts as a pneumonia forming early lesions, characterized by the infiltration of foamy macrophages containing mycobacterial antigens within alveoli, and progressing to necrotic pneumonias with an increasing density of mycobacterial antigens in the lesions. These necrotic pneumonic lesions appeared to either resolve as fibrocaseous lesions or lead to cavitation. The typical granulomatous inflammation, the hallmark of TB lesions, appeared later in the post-primary TB and surrounded the pneumonic lesions. These post-primary granulomas contained lesser mycobacterial antigens as compared to necrotic pneumonia.

CONCLUSIONS

Immunopathogenesis of post-primary TB is different from primary TB and starts as pneumonia. The early lesions of post-primary TB may progress or regress, holding the key to understanding how a host can develop the disease despite an effective TB immunity.

CT Scan Differences of Pulmonary TB According to Presence of Pleural Effusion

BACKGROUND

Subpleural micronodules and interlobular septal thickening are common CT scan findings in TB pleural effusion. These CT scan features could help us differentiate between TB pleural effusion and nonTB empyema.

RESEARCH QUESTION

Does the frequency of subpleural micronodules and interlobular septal thickening correlate with the presence of pleural effusion in patients with pulmonary TB?

STUDY DESIGN AND METHODS

CT scan findings of pulmonary TB, micronodules and their distribution (peribronchovascular, septal, subpleural, centrilobular, and random), large opacity (consolidation/macronodule), cavitation, tree-in-buds, bronchovascular bundle thickening, interlobular septal thickening, lymphadenopathy, and pleural effusion were retrospectively analyzed. Patients were divided into two groups according to the presence of pleural effusion. Clinicoradiologic findings of the two groups were then analyzed. We presented Benjamini-Hochberg critical value for multiple testing correction of CT scan findings, with a false discovery rate of 0.05.

RESULTS

Of a total of 338 consecutive patients diagnosed with pulmonary TB who underwent CT scans, 60 were excluded because of coexisting pulmonary diseases. The frequency of subpleural nodules (47/68, 69% in pulmonary TB with pleural effusion vs 30/210, 14% in pulmonary TB without effusion, P < .001, Benjamini-Hochberg [B-H] critical value = 0.0036) and interlobular septal thickening (55/68, 81% vs 134/210, 64%, P = .009, B-H critical value = 0.0107) was significantly higher in the group of patients with pulmonary TB with pleural effusion than in the group without pleural effusion. In contrast, tree-in-buds (20/68, 29% vs 101/210, 48%, P = .007, B-H critical value = 0.0071) were less frequently seen in patients with pulmonary TB with pleural effusion.

INTERPRETATION

Subpleural nodules and septal thickening were more common in pulmonary TB patients with pleural effusion than in those without pleural effusion. TB involvement of the lymphatics in the peripheral interstitium could be associated with the development of pleural effusion.

Radiomics analysis of lung CT for multidrug resistance prediction in active tuberculosis: a multicentre study

OBJECTIVES

Multidrug-resistant TB (MDR-TB) is a severe burden and public health threat worldwide. This study aimed to develop a radiomics model based on the tree-in-bud (TIB) sign and nodules and validate its predictive performance for MDR-TB.

METHODS

We retrospectively recruited 454 patients with proven active TB from two hospitals and classified them into three training and testing cohorts: TIB (n = 295, 102), nodules (n = 302, 97), and their combination (n = 261, 81). Radiomics features relating to TIB and nodules were separately extracted. The maximal information coefficient and recursive feature elimination were used to select informative features per the two signs. Two radiomics models were constructed to predict MDR-TB using a random forest classifier. Then, a combined model was built incorporating radiomics features based on these two signs. The capability of the models in the combined training and testing cohorts was validated with ROC curves.

RESULTS

Sixteen features were extracted from TIB and 15 from nodules. The AUCs of the combined model were slightly higher than those of the TIB model in the combined training cohort (0.911 versus 0.877, p > 0.05) and testing cohort (0.820 versus 0.786, p < 0.05) and similar to the performance of the nodules model in the combined training cohort (0.911 versus 0.933, p > 0.05) and testing cohort (0.820 versus 0.855, p > 0.05).

CONCLUSIONS

The CT-based radiomics models hold promise for use as a non-invasive tool in the prediction of MDR-TB.

CLINICAL RELEVANCE STATEMENT

Our study revealed that complementary information regarding MDR-TB can be provided by radiomics based on the TIB sign and nodules. The proposed radiomics models may be new markers to predict MDR in active TB patients.

KEY POINTS

• This is the first study to build, validate, and apply radiomics based on tree-in-bud sign and nodules for the prediction of MDR-TB. • The radiomics model showed a favorable performance for the identification of MDR-TB. • The combined model holds potential to be used as a diagnostic tool in routine clinical practice.

The Effect of Diabetes Control Status on CT Findings in Pulmonary Tuberculosis: Emphasis on Bronchial Erosive Changes

PURPOSE

Studies on the effect of diabetes mellitus (DM) on the radiologic findings of pulmonary tuberculosis (PTB) have reported inconsistent results. These findings may have been influenced by the glycemic control status of the patients studied. To our knowledge, no recent data have described the effect of the DM control status on CT findings in PTB in terms of medium-sized airway involvement that is visualized as bronchial erosion on CT. The aim of this present study was to determine whether the DM control status influenced radiological manifestations in patients with PTB, with an emphasis on bronchial erosive changes.

METHODS

We conducted a retrospective single-center study on patients who were newly diagnosed with PTB. A total of 426 consecutive patients with PTB who underwent CT scans at the time of diagnosis from 1 January 2017 to 31 March 2020 were included in this study. The included patients were categorized as having no DM (non-DM), controlled DM, or uncontrolled DM. The patient medical charts, microbiology study results, and pulmonary changes on the CT scans were analyzed.

RESULTS

Among 426 patients with PTB who underwent CT scans at the time of diagnosis, 91 were excluded either due to undetermined hemoglobin A1C (HbA1C) levels (n = 25) or concomitant pulmonary diseases (n = 66) that would make the analysis of the pulmonary changes on CT scans difficult. Finally, 335 patients were included in this study (224 men and 111 women; mean age, 59 years; range, 16-95 years). Among the 335 patients, 82 (24.5%) had DM and 52 of those (63.4%) had an uncontrolled status. The frequency of cavitation (43% vs. 23% vs. 79%, p < 0.001) and bronchial erosion (44% vs. 30% vs. 73%, p < 0.001) was significantly different between the three groups. The uncontrolled DM group showed a high frequency of cavitation and bronchial erosion compared to the non-DM (cavitation, p < 0.001 and bronchial erosion, p < 0.001) and controlled DM groups (p < 0.001 and p < 0.001). However, the frequency of cavitation and bronchial erosion in the controlled DM group was not different compared to the non-DM group.

CONCLUSION

The glycemic status (HbA1C ≥ 7.0), not the presence of DM, influenced the radiologic manifestations of PTB, especially in terms of medium-sized bronchial involvement, appearing as bronchial erosive changes and the feeding bronchus sign on chest CT scans. This difference in the uncontrolled DM group was likely to contribute to the higher frequency of cavitation.

A high-resolution 3D atlas of the spectrum of tuberculous and COVID-19 lung lesions

Our current understanding of the spectrum of TB and COVID-19 lesions in the human lung is limited by a reliance on low-resolution imaging platforms that cannot provide accurate 3D representations of lesion types within the context of the whole lung. To characterize TB and COVID-19 lesions in 3D, we applied micro/nanocomputed tomography to surgically resected, postmortem, and paraffin-embedded human lung tissue. We define a spectrum of TB pathologies, including cavitary lesions, calcium deposits outside and inside necrotic granulomas and mycetomas, and vascular rearrangement. We identified an unusual spatial arrangement of vasculature within an entire COVID-19 lobe, and 3D segmentation of blood vessels revealed microangiopathy associated with hemorrhage. Notably, segmentation of pathological anomalies reveals hidden pathological structures that might otherwise be disregarded, demonstrating a powerful method to visualize pathologies in 3D in TB lung tissue and whole COVID-19 lobes. These findings provide unexpected new insight into the spatial organization of the spectrum of TB and COVID-19 lesions within the framework of the entire lung.

A comparison of the chest radiographic and computed tomographic features of subclinical pulmonary tuberculosis

Subclinical pulmonary tuberculosis (PTB) is a recently described intermediate state of great interest, but about which little is known. This study sought to describe and compare the frequency of key radiologic features of subclinical PTB on chest radiograph (CXR) versus computed tomographic scan (CT), and to interpret the clinical and public health relevance of the differences. Diagnostic CXRs and CT scans of the thorax and neck in a 16-year cohort of subclinical PTB patients in Canada were re-acquired and read by two independent readers and arbitrated by a third reader. Logistic regression models were fit to determine how likely CXR features can be detected by CT scan versus CXR after adjustment for age and sex. Among 296 subclinical patients, CXRs were available in 286 (96.6%) and CT scans in 94 (32.9%). CXR features in patients with and without CT scans were comparable. Lung cavitation was 4.77 times (95% CI 1.95–11.66), endobronchial spread 19.36 times (95% CI 8.05–46.52), and moderate/far-advanced parenchymal disease 3.23 times (95% CI 1.66–6.30), more common on CT scan than CXR. We conclude that the extent to which CXRs under-detect key radiologic features in subclinical PTB is substantial. This may have public health and treatment implications.

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.

Tuberculosis Treatment Monitoring and Outcome Measures: New Interest and New Strategies

Despite the advent of new diagnostics, drugs and regimens, tuberculosis (TB) remains a global public health threat. A significant challenge for TB control efforts has been the monitoring of TB therapy and determination of TB treatment success. Current recommendations for TB treatment monitoring rely on sputum and culture conversion, which have low sensitivity and long turnaround times, present biohazard risk, and are prone to contamination, undermining their usefulness as clinical treatment monitoring tools and for drug development. We review the pipeline of molecular technologies and assays that serve as suitable substitutes for current culture-based readouts for treatment response and outcome with the potential to change TB therapy monitoring and accelerate drug development.

Centri-lobular pulmonary nodules on HRCT: incidence and approach for etiological diagnosis

Background

Centri-lobular nodules are the most common pattern of diffuse pulmonary nodules encountered on high-resolution computed tomography (HRCT). HRCT with post-processing techniques such as obtaining maximum intensity projection (MIP) is helpful in making centri-lobular nodules more conspicuous. The study aimed to highlight the role of HRCT with its reconstruction capabilities in the detection and characterization of centri-lobular pulmonary nodules, interpret the most frequent associated findings, and correlate with the clinical findings to reach the most appropriate diagnosis.

Results

The study included 58 patients; 41.4% males and 58.6% females. Their age ranged from 2 to 67 years with mean age of 25.69. The centri-lobular nodules numbers, distribution, shape, and associated HRCT chest findings were identified. The top three etiological diagnoses were infection/inflammation in 50.0% of cases followed by acute viral bronchiolitis in 27.6% and inhalation bronchiolitis in 19.0% of cases. Correlation of HRCT findings with the clinical diagnosis was carried out with consequent formulation of an algorithm for the diagnostic approach of various etiologies of centri-lobular pulmonary nodules.

Conclusions

HRCT is a useful tool in the detection and characterization of centri-lobular pulmonary nodules. It can be used to differentiate the different etiologies that share centri-lobular nodularity. Other associated features and multidisciplinary approach are essential for further characterization of the most relevant etiological diagnosis.

Comparative Role of MDCT and FDG-PET/CT in the Diagnostic Evaluation of Mediastinal Mass Lesions: An Institutional Experience

Background Mediastinal mass lesions span a wide histopathological and radiological spectrum. Partition of the mediastinum into specific compartments aids in differential diagnosis of mass lesions, assistance in biopsies, and other surgical procedures. Multidetector row computed tomography (MDCT) is a promising three-dimensional imaging tool allowing substantial anatomical volumes to be routinely covered with isotropic submillimeter spatial resolution to precisely localize lesions and biopsy needles for both benign and malignant disease lesions of the mediastinum.

Objective The aim of this study was to categorize mass lesions according to the mediastinal compartments to study their MDCT characteristics and to provide a comparative role of fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in the diagnostic evaluation of mediastinal mass lesions.

Materials and Methods Patients with clinical or radiological suspicion of mediastinal lesions on the basis of an abnormal chest radiograph were referred to the department of radiodiagnosis at a tertiary care center between April 2015 and December 2019 for MDCT evaluation. A total of 80 cases were correlated with the histopathological diagnosis excluding aneurysms. Size, CT density (Hounsfield unit [HU] mean), and maximum standardized uptake value (SUVmax) of mediastinal and chest wall lesions were determined on FDG-PET/CT.

Results This study included a total of 102 cases, 72 males and 29 females. Mediastinal mass lesions were most common in the age group 46 to 60 years. Anterior mediastinum (n = 43, 42.2%) is the most commonly involved compartment followed by posterior mediastinum (n = 37, 35.9%) and middle mediastinum (n = 22, 21.8%). Transcompartmental involvement is more commonly seen involving the anterior and middle mediastinum. The SUVmax, HU mean, and size were higher in malignant cases (p = 0.001, p = 0.003, and p = 0.004, respectively). The current study found a cutoff value of 4.61 for SUVmax to discriminate benign lesions from malignant ones with a sensitivity and specificity of 73.7 and 75.9%, respectively (area under the curve: 0.841, 95% confidence interval: 0.793–0.965, p = 0.0001). The values of SUVmax and HU mean were higher in solid benign lesions than those of cystic benign lesions (p = 0.007 and p = 0.003, respectively).

Conclusion In the current study, MDCT has high diagnostic accuracy of ∼94% overall as compared with histopathology, and 97 and 92% for benign and malignant lesions, respectively, in the evaluation of mediastinal mass lesions. FDG-PET/CT may be complementary to conventional imaging methods for the evaluation of mediastinal and chest wall mass lesions. However, confirmatory tissue sampling is required to confirm PET positive findings for the definite diagnosis.

Analysis of Clinical Features and Risk Factors in Pregnant Women With Miliary Pulmonary Tuberculosis After In Vitro Fertilization Embryo Transfer

Purpose

Miliary pulmonary tuberculosis (TB) among pregnant women after in vitro fertilization embryo transfer (IVF-ET) causes poor outcomes but is rarely reported. This study analyzed the clinical characteristics and risk factors of these patients to provide hints for further studies.

Method

The demographic characteristics, clinical manifestations, radiologic features, treatment, and outcomes of six patients diagnosed from May 2012 to August 2021 in Xiangya Hospital and 69 patients that were reported in English or Chinese literature from January 1980 to August 2021 were retrospectively analyzed. Continuous variables were compared between groups by t-test or Mann–Whitney U test, and categorical variables were compared between groups by chi-square test or Fisher exact test. Univariate and multiple logistic regression analyses were used to determine the predictors of respiratory failure.

Results

A total of 75 patients were included. The average age of patients was about 30 years. All patients had tubal obstruction; 5 of them were diagnosed with pelvic TB before. Thirteen cases had a history of pulmonary or extrapulmonary TB, six out of them without any antituberculosis treatment history. All patients were in their first or second trimester during the onset of symptoms. The average interval between onset of symptoms and radiologic examination was about 21 days. The most common abnormalities on chest computed tomography scan were multiple nodules, pulmonary infiltrate, and consolidation. Merely 10 patients obtained bacteriological diagnosis by Mycobacterium tuberculosis culture or polymerase chain reaction test. The other patients were clinically diagnosed. All the patients received antituberculosis treatment. Although 44% of patients had fatal complications, all cases were cured or improved after antituberculosis treatment. Unfortunately, only eight fetuses survived (10.6%). The most frequent and severe complication was type I respiratory failure (20%). Patients with expectoration, dyspnea, coarse breath sounds, ground-glass opacity, and pulmonary infiltrate or consolidation were more likely to have respiratory failure (P < 0.05). Ground-glass opacity (OR = 48.545, 95% CI = 2.366–995.974, P = 0.012) and pulmonary infiltrate or consolidation (OR = 19.943, 95% CI = 2.159–184.213, P = 0.008) were independent predictors for respiratory failure.

Conclusion

Tube infertility with underscreened or untreated TB is a risk factor for miliary TB during pregnancy after IVF-ET. Ground-glass opacity and pulmonary infiltrate or consolidation are predictors of respiratory failure. We demonstrate risk factors for incidence and complications to supply clues for future intervention and improve patient prognosis.

Deep-Learning-Aided Detection of Mycobacteria in Pathology Specimens Increases the Sensitivity in Early Diagnosis of Pulmonary Tuberculosis Compared with Bacteriology Tests

The histopathological diagnosis of mycobacterial infection may be improved by a comprehensive analysis using artificial intelligence. Two autopsy cases of pulmonary tuberculosis, and forty biopsy cases of undetected acid-fast bacilli (AFB) were used to train AI (convolutional neural network), and construct an AI to support AFB detection. Forty-two patients underwent bronchoscopy, and were evaluated using AI-supported pathology to detect AFB. The AI-supported pathology diagnosis was compared with bacteriology diagnosis from bronchial lavage fluid and the final definitive diagnosis of mycobacteriosis. Among the 16 patients with mycobacteriosis, bacteriology was positive in 9 patients (56%). Two patients (13%) were positive for AFB without AI assistance, whereas AI-supported pathology identified eleven positive patients (69%). When limited to tuberculosis, AI-supported pathology had significantly higher sensitivity compared with bacteriology (86% vs. 29%, p = 0.046). Seven patients diagnosed with mycobacteriosis had no consolidation or cavitary shadows in computed tomography; the sensitivity of bacteriology and AI-supported pathology was 29% and 86%, respectively (p = 0.046). The specificity of AI-supported pathology was 100% in this study. AI-supported pathology may be more sensitive than bacteriological tests for detecting AFB in samples collected via bronchoscopy.

Correlations Between Inflammatory Biomarkers in Tuberculosis-Associated Obstructive Pulmonary Disease Patients With Anxiety and Depression

Introduction

Tuberculosis-associated obstructive pulmonary disease (TOPD), anxiety, and depression are significant public health problems worldwide and their prevalence is common. These diseases interfere with physical, psychosocial, and economic well-being, resulting in unemployment, prolonged hospitalization, abstinence from working, and isolation.

Subjects and methods

This is a single-center, cross-sectional cohort, observational study conducted in a tertiary care hospital over six years to understand spirometry, laboratory profiles, as well as the impact on overall health, daily life, and perceived well-being in patients with TOPD.

Result

The sample size of the study was 73 patients. A total of 43 (58.5%) patients had depression with an average St. George's Respiratory Questionnaire for chronic obstructive pulmonary disease (SGRQ-C) score of 67.5, and 16 (21.9%) patients had anxiety with an average SGRQ-C score of 78.9. In the patients who scored higher on the Hamilton Depression Rating Scale (HAM-D), there was a significant correlation between Hamilton Anxiety Rating Scale (HAM-A) and HAM-D scores, as well as C-reactive protein (CRP) levels and WBC counts. In 16 (21.9%) of the patients with moderate to severe anxiety, there was a statistically significant negative correlation between higher HAM-A scores and lower WBC counts. Anxiety, depression, CRP level, WBC count, and serum fibrinogen did not show a significant correlation with the Global Initiative for Chronic Obstructive Lung Disease (GOLD) groups-based assessment of TOPD severity. A high serum fibrinogen level did not correlate with a high HAM-D score, nor did a high CRP level correlate with a high HAM-A score.

Conclusion

Psychiatric comorbidities like depression are associated with increased inflammation in chronic diseases like TOPD, but no definitive biomarker has been identified and further studies are required to identify suitable biomarkers.

Active pulmonary tuberculosis: something old, something new, something borrowed, something blue

Tuberculosis remains a major global health issue affecting all countries and age groups. Radiology plays a crucial role in the diagnosis and management of pulmonary tuberculosis (PTB). This review aims to improve understanding and diagnostic value of imaging in PTB. We present the old, well-established findings ranging from primary TB to the common appearances of post-primary TB, including dissemination with tree-in-bud nodularity, haematogenous dissemination with miliary nodules and lymphatic dissemination. We discuss new concepts in active PTB with special focus on imaging findings in immunocompromised individuals. We illustrate PTB appearances borrowed from other diseases in which the signs were initially described: the reversed halo sign, the galaxy sign and the cluster sign. There are several radiological signs that have been shown to correlate with positive or negative sputum smears, and radiologists should be aware of these signs as they play an important role in guiding the need for isolation and empirical anti-tuberculous therapy.

Chest Imaging in the Diagnosis and Management of Pulmonary Tuberculosis: The Complementary Role of Thoraci Ultrasound

Tuberculosis (TB) is a severe infectious disease that still represents a major cause of mortality and morbidity worldwide. For these reasons, clinicians and radiologists should use all the available diagnostic tools in the assessment of the disease in order to provide precise indications about starting an anti-tubercular treatment and reduce risk of TB transmission and complications especially in developing countries where the disease is still endemic. As TB mycobacteria are mainly transmitted through respiratory droplets, the pulmonary parenchyma is usually the first site of infection. As a result, chest imaging plays a central role in the diagnostic process. Thoracic ultrasound (TUS) is a portable, non-invasive, radiation-free, and cost-contained technology which could be easily available in resource-limited settings. This perspective article focuses on the potential role of TUS in the diagnosis and management of patients with pulmonary TB. Unfortunately, there are still insufficient evidence and too contrasting data to judge TUS as an appropriate diagnostic method for the screening of the disease. Despite this, TUS may have a useful role in identifying pleural and anterior pericardial effusions or in the identification of abscesses of the anterior chest wall and paraspinal collections in low- and middle-income settings. In addition, TUS seems to have a milestone role in guiding minimally invasive interventional procedures, such as placement of chest tubes, drainage of loculated collections, thoracentesis and pericardiocentesis, and percutaneous biopsy of subpleural pulmonary consolidations or pleural plaques.

Micro-Computed Tomography Analysis of the Human Tuberculous Lung Reveals Remarkable Heterogeneity in Three-dimensional Granuloma Morphology

Rationale: Our current understanding of tuberculosis (TB) pathophysiology is limited by a reliance on animal models, the paucity of human TB lung tissue, and traditional histopathological analysis, a destructive two-dimensional approach that provides limited spatial insight. Determining the three-dimensional (3D) structure of the necrotic granuloma, a characteristic feature of TB, will more accurately inform preventive TB strategies.Objectives: To ascertain the 3D shape of the human tuberculous granuloma and its spatial relationship with airways and vasculature within large lung tissues.Methods: We characterized the 3D microanatomical environment of human tuberculous lungs by using micro computed tomography, histopathology, and immunohistochemistry. By using 3D segmentation software, we accurately reconstructed TB granulomas, vasculature, and airways in three dimensions and confirmed our findings by using histopathology and immunohistochemistry.Measurements and Main Results: We observed marked heterogeneity in the morphology, volume, and number of TB granulomas in human lung sections. Unlike depictions of granulomas as simple spherical structures, human necrotic granulomas exhibit complex, cylindrical, branched morphologies that are connected to the airways and shaped by the bronchi. The use of 3D imaging of human TB lung sections provides unanticipated insight into the spatial organization of TB granulomas in relation to the airways and vasculature.Conclusions: Our findings highlight the likelihood that a single, structurally complex lesion could be mistakenly viewed as multiple independent lesions when evaluated in two dimensions. In addition, the lack of vascularization within obstructed bronchi establishes a paradigm for antimycobacterial drug tolerance. Lastly, our results suggest that bronchogenic spread of Mycobacterium tuberculosis reseeds the lung.

Discriminating Small-Sized (2 cm or Less), Noncalcified, Solitary Pulmonary Tuberculoma and Solid Lung Adenocarcinoma in Tuberculosis-Endemic Areas

Background. Pulmonary tuberculoma can mimic lung malignancy and thereby pose a diagnostic dilemma to clinicians. The purpose of this study was to establish an accurate, convenient, and clinically practical model for distinguishing small-sized, noncalcified, solitary pulmonary tuberculoma from solid lung adenocarcinoma. Methods. Thirty-one patients with noncalcified, solitary tuberculoma and 30 patients with solid adenocarcinoma were enrolled. Clinical characteristics and CT morphological features of lesions were compared between the two groups. Multivariate logistic regression analyses were applied to identify independent predictors of pulmonary tuberculoma and lung adenocarcinoma. Receiver operating characteristic (ROC) analysis was performed to investigate the discriminating efficacy. Results. The mean age of patients with tuberculoma and adenocarcinoma was 46.8 ± 12.3 years (range, 28–64) and 61.1 ± 9.9 years (range, 41–77), respectively. No significant differences were observed concerning smoking history and smoking index, underlying disease, or tumor markers between the two groups. Univariate and multivariate analyses showed age and lobulation combined with pleural indentation demonstrated excellent discrimination. The sensitivity, specificity, accuracy, and the area under the ROC curve were 87.1%, 93.3%, 90.2%, and 0.956 (95% confidence interval (CI), 0.901–1.000), respectively. Conclusion. The combination of clinical characteristics and CT morphological features can be used to distinguish noncalcified, solitary tuberculoma from solid adenocarcinoma with high diagnostic performance and has a clinical application value.

Cancer or Tuberculosis: A Comprehensive Review of the Clinical and Imaging Features in Diagnosis of the Confusing Mass

Confusing masses constitute a challenging clinical problem for differentiating between cancer and tuberculosis diagnoses. This review summarizes the major theories designed to identify factors associated with misdiagnosis, such as imaging features, laboratory tests, and clinical characteristics. Then, the clinical experiences regarding the misdiagnosis of cancer and tuberculosis are summarized. Finally, the main diagnostic points and differential diagnostic criteria are explored, and the characteristics of multimodal imaging and radiomics are summarized.

Chest Radiographs and CT Findings during Healthcare Workers' Tuberculosis Screening Using Interferon-Gamma Release Assay: Retrospective Observational Study

Purpose

To investigate the incidence of tuberculosis (TB) in healthcare workers (HCWs) with positive interferon-gamma release assay (IGRA) results based on chest X-ray (CXR) and CT findings and determine the role of imaging in the diagnosis of TB.

Materials and Methods

Among 1976 hospital personnel screened for TB using IGRA, IGRA-positive subjects were retrospectively investigated. Clustered nodular and/or linear streaky opacities in the upper lung zone were considered positive on CXR. The CT findings were classified as active, indeterminate, inactive, or normal. The active or indeterminate class was considered CT-positive.

Results

IGRA was positive in 255 subjects (12.9%). CXR and CT were performed in 249 (99.2%) and 113 subjects (45.0%), respectively. CXR- and CT-positive findings were found in 7 of 249 (2.8%) and 9 of 113 (8.0%) patients, respectively. Among the nine CT-positive subjects, active and indeterminate TB findings were found in 6 (5.3%) and 3 (2.7%) patients, respectively. Microbiological tests, including acid-fast bacilli staining, culture, and polymerase chain reaction for TB, were negative in all nine CT-positive subjects. Empirical anti-TB medications were administered to 9 CT-positive subjects, and 3 of these nine subjects were CXR-negative for pulmonary TB.

Conclusion

CT helped diagnose asymptomatic TB in IGRA-positive HCWs.

Hafnia alvei pneumonia: a rare cause of infection in the multimorbid or immunocompromised

Hafnia alvei is a rare, poorly understood commensal bacterium which has, on occasion, been shown to infect humans. We present two cases. The first patient presented with a 1-week history of dyspnoea, pleurisy and a productive cough, and the second with a prodrome of fatigue and night sweats. The former had a history of severe chronic obstructive pulmonary disease and the latter had a history of Crohn's disease. Both patients had underlying comorbidities and immunosuppression, but differed in presentation, radiological findings and recovery. This case series aims to remind readers of the broad differential of pathogens that can lead to disease in the immunocompromised and that one should not dismiss atypical cultured bacteria as commensal too hastily.

The Pathogenesis of Tuberculosis-The Koch Phenomenon Reinstated

Research on the pathogenesis of tuberculosis (TB) has been hamstrung for half a century by the paradigm that granulomas are the hallmark of active disease. Human TB, in fact, produces two types of granulomas, neither of which is involved in the development of adult type or post-primary TB. This disease begins as the early lesion; a prolonged subclinical stockpiling of secreted mycobacterial antigens in foamy alveolar macrophages and nearby highly sensitized T cells in preparation for a massive necrotizing hypersensitivity reaction, the Koch Phenomenon, that produces caseous pneumonia that is either coughed out to form cavities or retained to become the focus of post-primary granulomas and fibrocaseous disease. Post-primary TB progresses if the antigens are continuously released and regresses when they are depleted. This revised paradigm is supported by nearly 200 years of research and suggests new approaches and animal models to investigate long standing mysteries of human TB and vaccines that inhibit the early lesion to finally end its transmission.

Fine-needle aspiration cytology of mediastinal masses: An institutional experience

Introduction:

Mediastinal masses are uncommon in clinical practice. Fine-needle aspiration cytology (FNAC) is an important and useful investigation and is considered next to imaging in the diagnosis of mediastinal lesions.

Aim:

To analyze the mediastinal masses diagnosed on FNAC.

Materials and Methods:

We retrospectively retrieved twenty-five cases, which underwent FNAC under ultrasound or computed tomography (CT) guidance for mediastinal masses, over a period of 4 years. Histopathological correlations were done in cases wherever available.

Results:

Among twenty-five cases, which were diagnosed through FNAC, eighteen were males and seven were females with age ranging from 6 to 85 years. Ultrasonography (USG)-guided FNAC was performed in three patients, while CT-guided FNAC was performed in twenty-two patients. Out of twenty-five cases, seventeen cases were malignant, six were benign, and two cases were inadequate. FNAC was useful in the diagnosis of 83.3% of cases. Biopsy and/or cell block correlations were available in fourteen cases. In the malignant category, mediastinal invasion by either squamous cell carcinoma or adenocarcinoma constituted the highest number with eight (47%) out of seventeen cases. Among the nonneoplastic conditions, nonspecific inflammation was the most common cause with two cases (8%) out of total cases followed by one case each of tuberculosis, schwannoma, thymoma, and cystic lesion.

Conclusion:

USG or CT-guided FNAC is a safe, minimally invasive, and cost-effective procedure, which can provide a precise diagnosis in the mediastinal masses, and may obviate the need for an invasive surgical approach.

Dual-Energy Computed Tomography Lung in patients of Pulmonary Tuberculosis

Objectives

The objective of this study was to characterize findings of high-resolution computed tomography (HRCT) and dual-energy CT (DECT) (80 keV, 140 keV, and mixed) in pulmonary tuberculosis (TB) patients and to compare and correlate HRCT and DECT findings.

Material and Methods

This cross-sectional study was conducted on 67 patients of 18-65 years of age who were suspected cases of pulmonary TB with signs and symptoms of cough, fever, hemoptysis, sputum, night sweats, and weight loss with positive sputum AFB examinations/bronchoalveolar lavage. All the patients subjected to HRCT scan and followed with DECT scan. Comparison of various imaging techniques (DECT 80 keV, DECT 140 keV, and DECT mixed) with HRCT was done for detecting lung findings and data so obtained were subjected to statistical analysis.

Results

On comparing the various imaging techniques with HRCT for detecting consolidation, tree in bud pattern, cavitary lesions, ground-glass opacity, bronchiectasis, atelectasis, nodules, granuloma, peribronchial thickening, and fibrosis, the maximum agreement of HRCT was found with DECT 80 keV and minimum agreement was found with DECT 140 keV.

Conclusion

The study concluded that DECT 80 keV monochromatic reconstructions among 80 keV, mixed, and 140 keV monochromatic reconstructions in lung parenchyma window settings are a faster and better analytical tool for the assessment of findings of pulmonary TB when compared with HRCT.

The Diagnosis and Treatment of Tuberculosis

BACKGROUND

Around 10 million people worldwide contract tuberculosis every year. According to the World Health Organization (WHO), approximately one-quarter of the world's population is latently infected with Mycobacterium tuberculosis. In Ger- many, the incidence of tuberculosis was in decline over several decades but rose in 2015 to 7.3 new cases per 100 000 persons. In 2018, a total of 5429 new cases were documented, corresponding to 6.5 new cases per 100 000 persons.

METHODS

This article is based on literature retrieved by a selective search in PubMed and on the authors' clinical experience.

RESULTS

Tuberculosis involves the lungs in almost 75% of patients but can generally involve any organ. In Germany, the majority of patients come from high-incidence countries. If a patient's differential diagnosis includes tuberculosis, the main tests for the detection of the pathogen in sputum and tissue samples are culture (the gold standard), microscopy, and nucleic acid amplification tests. Imaging studies are also used for diagnosis and follow-up. The standard treatment consists of a combination of isoniazid, rifampicin, ethambutol, and pyrazinamide, followed by a combination of isoniazid and rifampicin only. Liver damage is one of the more common adverse effects of this treatment, arising in 2.4% of patients. Multidrug-resistant tuberculosis, which is rare in Germany (around 100 cases per year), should be treated in special- ized centers.

CONCLUSION

Rapid diagnosis and targeted treatment are essential to prevent an unfavorable course of the disease as well as its transmission to other individuals. In patients presenting with unclear symptoms, tuberculosis should always be considered as a differential diagnosis. The diagnosis of latent tuberculosis and decision-making regarding its treatment are difficult because of the lack of specific biomarkers and of relevant data from clinical trials.

Angiographic Findings and Outcomes of Bronchial Artery Embolization in Patients with Pulmonary Tuberculosis

Objective

We aimed to evaluate the angiographic findings and outcomes of bronchial artery embolization in tuberculosis patients and to compare them with those of non-tuberculosis patients.

Materials and Methods

Patients who underwent bronchial artery embolization in a single interventional radiology department with hemoptysis were reviewed. A total of 89 patients (66 males and 23 females; mean age 52.71±15.37) were incorporated in the study. The patients were divided into two groups: tuberculosis group (n=36) and non-tuberculosis group (16 malignancy, 22 bronchiectasis, 6 pulmonary infection, 5 chronic obstructive pulmonary disease, 4 idiopathic; n=53). Angiography and embolization procedure were performed by interventional radiologists with 5, 10, and 20 years of experience. Angiographic findings were classified as tortuosity, hypertrophy, hypervascularity, aneurysm, bronchopulmonary shunt, extravasation, and normal bronchial artery. Chi-square test was used to compare angiographic findings between tuberculosis and non-tuberculosis patient groups.

Results

Bronchopulmonary shunt was found to be significantly higher in the tuberculosis group as compared to that in the non-tuberculosis group (p=0.002). Neither of the groups showed a statistically significant difference with respect to recurrence (p=0.436).

Conclusion

Bronchial artery embolization is a useful and effective treatment method of hemoptysis in tuberculosis. Evaluation of bronchopulmonary shunts in patients with tuberculosis is critical for the reduction of catastrophic complications.

Cavitary tuberculosis: the gateway of disease transmission

Tuberculosis continues to be a major threat to global health. Cavitation is a dangerous consequence of pulmonary tuberculosis associated with poor outcomes, treatment relapse, higher transmission rates, and development of drug resistance. However, in the antibiotic era, cavities are often identified as the most extreme outcome of treatment failure and are one of the least-studied aspects of tuberculosis. We review the epidemiology, clinical features, and concurrent standards of care for individuals with cavitary tuberculosis. We also discuss developments in the understanding of tuberculosis cavities as dynamic physical and biochemical structures that interface the host response with a unique mycobacterial niche to drive tuberculosis-associated morbidity and transmission. Advances in preclinical models and non-invasive imaging can provide valuable insights into the drivers of cavitation. These insights will guide the development of specific pharmacological interventions to prevent cavitation and improve lung function for individuals with tuberculosis.

Endobronchial Tuberculosis: A Rare Presentation

Endobronchial tuberculosis (EBTB) is an infection of the tracheobronchial tree by Mycobacterium tuberculosis. It is common among young females. Patient can present with fever, cough, wheeze, with or without any constitutional symptoms. It presents as a diagnostic dilemma, as patient sputum smear can be false negative. CT scan may or may not show any abnormality, or any endobronchial lesion. Bronchoscopy with bronchoalveolar lavage and biopsy offers the diagnostic choice. We hereby report a case of a young immunocompetent Asian female who was found to have endobronchial pathology, leading to diagnosis and timely therapy. 

Clustered micronodules as predominant manifestation on CT: A sign of active but indolently evolving pulmonary tuberculosis

OBJECTIVE

To investigate the prevalence, patient characteristics, and natural history of clustered micronodules (CMs) in active pulmonary tuberculosis.

MATERIALS AND METHODS

From January 2013 through July 2018, 833 consecutive patients with bacteriologically or polymerase chain reaction-proven active pulmonary tuberculosis were retrospectively evaluated. CMs were defined as a localized aggregation of multiple dense discrete micronodules, which primarily distributed around small airways distal to the level of the segmental bronchus: small airways surrounded by CMs maintained luminal patency and the CMs might coalesce into a larger nodule. The patients were dichotomized according to whether the predominant computed tomography (CT) abnormalities were CMs. We analyzed radiologic and pathologic findings in patients whose predominant diagnostic CT abnormalities were CMs, along with those of incidental pre-diagnostic CT scans, if available. Chi-square, McNemar, Student t-test and Wilcoxon-signed rank test were performed.

RESULTS

CMs were the predominant CT abnormality in 2.6% of the patients (22/833, 95% CI, 1.8-4.0%) with less sputum smear-positivity (4.8% vs 31.0%; p = .010) and a similar proportion of immunocompromised status (40.9% vs 46.0%; p = .637) than those without having CMs as the predominant CT abnormality. The time interval for minimal radiologic progression was 6.4 months. The extent of CMs increased with disease progression, frequently accompanied by consolidation and small airway wall thickening. Pathologically, smaller CMs were non-caseating granulomas confined to the peribronchiolar interstitium, whereas larger CMs were caseating granulomas involving lung parenchyma. Two of the five patients with a pre-diagnostic CT scan obtained more than 50 months pre-diagnosis showed an incipient stage of CMs, in which they were small peribronchiolar nodules.

CONCLUSION

Active pulmonary tuberculosis manifested predominantly as CMs in 2.6% of patients, with scarce of acid-fast bacilli smear-positivity and no association with impaired host immunity. CMs indolently progressed, accompanied by consolidation and small airway wall thickening, and originated from small nodules.

Pulmonary High-Resolution Computed Tomography (HRCT) Findings of Patients with Early-Stage Coronavirus Disease 2019 (COVID-19) in Hangzhou, China

BACKGROUND The aim of this study was to investigate the imaging manifestations of early-stage coronavirus disease 2019 (COVID-19) and to provide imaging basis for early detection of suspected cases and stratified intervention. MATERIAL AND METHODS From 20 January 2020 to 2 February 2020, 6 patients diagnosed with COVID-19, including 1 male and 5 females, were retrospectively reviewed in Zhejiang Hospital. These cases were clinically assessed and classified as common COVID-19. All patients underwent thoracic high-resolution computed tomography (HRCT) within 2 days after the onset of symptoms, and their images were viewed by 2 radiologists who were blind to their clinical records. RESULTS CT images of 6 confirmed patients were collected. Two of the 6 patients (33.3%) had bilateral lung involvements and 4 (66.7%) had single-lung involvement. Two cases (33.3%) had a single lesion, 2 cases (33.3%) had 2 lesions, and 2 cases (33.3%) had multiple lesions. There were 2 cases (33.3%) with focal subpleural distribution and 1 case (16.7%) along the bronchial vascular bundle. Five cases (83.3%) had ground-glass opacities, 4 cases (66.7%) had ground-glass nodules, 1 case (16.7%) had thickened lobular septum, 2 cases (33.3%) had thickened bronchial wall, 2 cases (33.3%) had halo sign,1 case (16.7%) had crazy-paving sign, and 1 case (16.7%) had tree-in-bud sign. CONCLUSIONS The imaging manifestations of early-stage COVID-19 are relatively mild, and the imaging findings of some patients are not typical, which can easily lead to missed diagnoses. Thus, suspected cases need to be closely monitored, and epidemiological history and clinical laboratory examination should also be considered during diagnosis.

Comparison of the chest computed tomography findings between patients with pulmonary tuberculosis and those with Mycobacterium avium complex lung disease

BACKGROUND

Since the computed tomography (CT) findings of nontuberculous mycobacterial lung disease are similar to those of pulmonary tuberculosis (PTB), we often have difficulty differentiating the two. In this study, we compared the differences in chest CT findings and their locations between cases of PTB and Mycobacterium avium complex lung disease (MACLD).

METHODS

The subjects were 100 MACLD patients and 42 PTB patients treated at our hospital from May 2005 to August 2015. The CT findings were retrospectively evaluated.

RESULTS

PTB more frequently showed lung shadows with calcification inside the lesion, calcification of the mediastinal/hilar lymph node, and pleural effusion on CT than MACLD, while extensive bronchiectasis and granular/large shadows connected to bronchiectasis were more frequently observed with MACLD than PTB. For cavitary lesions, the thinnest part of the cavity wall with MACLD was thinner than that with PTB. Granular shadows, large shadows, and bronchiectasis were typically distributed to the right upper lobe and left upper division in PTB cases vs. the right intermediate lobe and left lingula in MACLD.

CONCLUSIONS

Chest CT findings would therefore be useful for distinguishing PTB and MACLD when typical findings are observed.

Pulmonary Cryptococcosis in a Nurse Initially Suspected of Having Pulmonary Tuberculosis

Patient: Female, 34-year-old

Final Diagnosis: Pulmonary cryptococcosis

Symptoms: None

Medication: —

Clinical Procedure: Bronchoscopy

Specialty: Infectious Diseases

Tuberculosis: a focused review for the emergency medicine clinician

INTRODUCTION

Tuberculosis (TB) is a common disease worldwide, affecting nearly one-third of the world's population. While TB has decreased in frequency in the United States, it remains an important infection to diagnose and treat.

OBJECTIVE

This narrative review discusses the evaluation and management of tuberculosis, with an emphasis on those factors most relevant for the emergency clinician.

DISCUSSION

TB is caused by Mycobacterium tuberculosis and is highly communicable through aerosolized particles. A minority of patients will develop symptomatic, primary disease. Most patients will overcome the initial infection or develop a latent infection, which can reactivate. Immunocompromised states increase the risk of primary and reactivation TB. Symptoms include fever, prolonged cough, weight loss, and hemoptysis. Initial diagnosis often includes a chest X-ray, followed by serial sputum cultures. If the patient has a normal immune system and a normal X-ray, active TB can be excluded. Newer tests, including nucleic acid amplification testing, can rapidly diagnose active TB with high sensitivity. Treatment for primary and reactivation TB differs from latent TB. Extrapulmonary forms can occur in a significant proportion of patients and involve a range of different organ systems. Patients with human immunodeficiency virus are high-risk and require specific considerations.

CONCLUSIONS

TB is a disease associated with significant morbidity and mortality. The emergency clinician must consider TB in the appropriate setting, based on history and examination. Accurate diagnosis and rapid therapy can improve patient outcomes and reduce the spread of this communicable disease.

Chest imaging using signs, symbols, and naturalistic images: a practical guide for radiologists and non-radiologists

Several imaging findings of thoracic diseases have been referred-on chest radiographs or CT scans-to signs, symbols, or naturalistic images. Most of these imaging findings include the air bronchogram sign, the air crescent sign, the arcade-like sign, the atoll sign, the cheerios sign, the crazy paving appearance, the comet-tail sign, the darkus bronchus sign, the doughnut sign, the pattern of eggshell calcifications, the feeding vessel sign, the finger-in-gloove sign, the galaxy sign, the ginkgo leaf sign, the Golden-S sign, the halo sign, the headcheese sign, the honeycombing appearance, the interface sign, the knuckle sign, the monod sign, the mosaic attenuation, the Oreo-cookie sign, the polo-mint sign, the presence of popcorn calcifications, the positive bronchus sign, the railway track appearance, the scimitar sign, the signet ring sign, the snowstorm sign, the sunburst sign, the tree-in-bud distribution, and the tram truck line appearance. These associations are very helpful for radiologists and non-radiologists and increase learning and assimilation of concepts.Therefore, the aim of this pictorial review is to highlight the main thoracic imaging findings that may be associated with signs, symbols, or naturalistic images: an "iconographic" glossary of terms used for thoracic imaging is reproduced-placing side by side radiological features and naturalistic figures, symbols, and schematic drawings.

Clinical characteristics and chest computed tomography findings of smear-positive and smear-negative pulmonary tuberculosis in hospitalized adult patients

Pulmonary tuberculosis (PTB) continues to be one of the significant public health threats with significant morbidity and mortality. The present study was aimed to assess the clinical characteristics and chest computed tomography (CT) findings of smear-positive and smear-negative PTB in hospitalized adult patients.Hospitalized adult patients diagnosed with PTB by positive Mycobacterium tuberculosis growth on acid-fast bacilli culture from bronchial aspiration or sputum from 2015 to 2017 were reviewed. Only the patients who had chest CT within 14 days of the diagnosis of PTB were included. Medical records and CT images were analyzed.A total of 189 patients was enrolled. The median age was 62 years, and there were 118 males (62.4%). More than half of the patients had underlying chronic medical conditions (55.5%). The most common CT finding was nodular lesions (96.8%). The patients were categorized in 2 groups of smear-positive (n = 94, 49.7%) and smear-negative (n = 95, 50.3%). Between 2 groups, there was no difference in underlying medical conditions. However, there were more lesions of cavity, consolidation, bronchiectasis, upper lobe involvement, multiple lobe involvement, and lymphadenopathy in the smear-positive group. A predictive model for smear-positive tuberculosis was created based on the comparison analysis that had an area of 0.724 under the receiver operating characteristic curve. In a multivariate logistic regression analysis, CT findings of consolidation (odds ratio [OR] 2.521, 95% confidence interval [CI] 1.175-5.408, P = .02), lymphadenopathy (OR 1.947, 95% CI 1.025-3.696, P = .04), and multi-lobe involvement (OR 2.795, 95% CI 1.084-7.205, P = .03) were associated with smear-positive PTB.PTB patients who have chest CT findings of cavity, consolidation, bronchiectasis, upper lobe involvement, multiple lobe involvement, and lymphadenopathy may be at higher risk for smear-positive TB. A predictive model may be helpful for further assessment.

Correlation between the tuberculin skin test and T-SPOT.TB in patients with suspected tuberculosis infection: A pilot study

T-SPOT.TB is a novel screening method for Mycobacterium tuberculosis infection. However, it is controversial whether T-SPOT.TB should become an alternative method to the tuberculin skin test (TST) for screening M. tuberculosis infections. The present study aimed to evaluate this issue based on the retrospective analysis of clinical cases. TST and T-SPOT.TB tests were used on patients with suspected M. tuberculosis infection on admission. Demographic data and clinical information, including previous history of M. tuberculosis infection, were collected. A total of 118 patients were included in the analysis, among whom 30 (25.4%) were diagnosed with active M. tuberculosis infection, and seven patients (5.9%) were currently receiving immunosuppressive treatment. The overall sensitivity and specificity of the TST were 76.7 and 77.3%, respectively, while they were 88.3 and 68.1%, respectively, for the T-SPOT.TB test. Patients with large TST indurations had a higher number of gamma interferon-producing T cells among peripheral blood mononuclear cells compared with those of TST-negative patients. In conclusion, the T-SPOT.TB test had a higher sensitivity than the TST, but the difference was not statistically significant. Neither the T-SPOT.TB test nor the TST was sufficiently accurate to detect active M. tuberculosis infection.

Sex Disparity in Severity of Lung Lesions in Newly Identified Tuberculosis Is Age-Associated

Background: The age-associated characteristic of computed tomography (CT) images of tuberculosis (TB) and the reason for male bias in TB are still not clear. Methods: We compared the CT images, clinical inflammatory indices and sputum bacterial counts between 594 non-smoking men and women with newly diagnosed TB with matched large span of ages from 15 to 92 years old. Logistic regression analyses were used to identify the cavity-associated factors of men and women, separately and in combination. Results: Sputum bacterial counts, ratio of cavities, lung injury scores, and level of C reactive protein were significantly higher in men than in women with ages from 15 to 74, but not in cases older than 75. In CT images, thick walled cavity, cicatricial emphysema and parenchymal bands were present in men at ages of 15-74 more than matched women. Ratios of cases with lobular emphysema and pleural effusion were higher in men after age of 56. While ratios of cases with parenchymal bands, calcification, pleural effusion, pleural thickening, lobular emphysema and bronchovascular distortion increased with aging, those of centrilobular nodules, micronodules and tree in bud decreased with aging in men. Erythrocyte sedimentation rate (ESR) increased with aging, but no differences were found between men and women in ESR or T-SPOT TB tests. Higher complement C4 and lower body mass index in men and positive result in anti-TB antibody test in women were strongly associated with the presence of cavity. Conclusions: The sex bias in TB is age-associated. TB prevention, treatment and research should take differences of sex and age into account.

Trends in Diagnosis for Active Tuberculosis Using Nanomaterials

Background:

Tuberculosis (TB), one of the leading causes of death worldwide, is difficult to diagnose based only on signs and symptoms. Methods for TB detection are continuously being researched to design novel effective clinical tools for the diagnosis of TB.

Objective:

This article reviews the methods to diagnose TB at the latent and active stages and to recognize prospective TB diagnostic methods based on nanomaterials.

Methods:

The current methods for TB diagnosis were reviewed by evaluating their advantages and disadvantages. Furthermore, the trends in TB detection using nanomaterials were discussed regarding their performance capacity for clinical diagnostic applications.

Results:

Current methods such as microscopy, culture, and tuberculin skin test are still being employed to diagnose TB, however, a highly sensitive point of care tool without false results is still needed. The utilization of nanomaterials to detect the specific TB biomarkers with high sensitivity and specificity can provide a possible strategy to rapidly diagnose TB. Although it is challenging for nanodiagnostic platforms to be assessed in clinical trials, active TB diagnosis using nanomaterials is highly expected to achieve clinical significance for regular application. In addition, aspects and future directions in developing the high-efficiency tools to diagnose active TB using advanced nanomaterials are expounded.

Conclusion:

This review suggests that nanomaterials have high potential as rapid, costeffective tools to enhance the diagnostic sensitivity and specificity for the accurate diagnosis, treatment, and prevention of TB. Hence, portable nanobiosensors can be alternative effective tests to be exploited globally after clinical trial execution.

Infection in Immunocompromised Hosts: Imaging

Immunocompromised patients are encountered with increasing frequency in clinical practice. In addition to the acquired immunodeficiency syndrome (AIDS), therapy for malignant disease, and immune suppression for solid organ transplants, patients are now rendered immunosuppressed by advances in treatment for a wide variety of autoimmune diseases. The number of possible infecting organisms can be bewildering. Recognition of the type of immune defect and the duration and depth of immunosuppression (particularly in hematopoietic and solid organ transplants) can help generate a differential diagnosis. Radiologic imaging plays an important role in the detection and diagnosis of chest complications occurring in immunocompromised patients; however, chest radiography alone seldom provides adequate sensitivity and specificity. High-resolution computed tomography (CT) can provide better sensitivity and specificity, but even CT findings may be nonspecific findings unless considered in conjunction with the clinical context. Combination of CT pattern, clinical setting, and immunologic status provides the best chance for an accurate diagnosis. In this article, CT findings have been divided into 4 patterns: focal consolidation, nodules/masses, small/micronodules, and diffuse ground-glass attenuation/consolidation. Differential diagnoses are suggested for each pattern, adjusted for both AIDS and non-AIDS immunosuppressed patients.

High-resolution computed tomography findings of pulmonary tuberculosis in lung transplant recipients

OBJECTIVE

Respiratory infections constitute a major cause of morbidity and mortality in solid organ transplant recipients. The incidence of pulmonary tuberculosis is high among such patients. On imaging, tuberculosis has various presentations. Greater understanding of those presentations could reduce the impact of the disease by facilitating early diagnosis. Therefore, we attempted to describe the HRCT patterns of pulmonary tuberculosis in lung transplant recipients.

METHODS

From two hospitals in southern Brazil, we collected the following data on lung transplant recipients who developed pulmonary tuberculosis: gender; age; symptoms; the lung disease that led to transplantation; HRCT pattern; distribution of findings; time from transplantation to pulmonary tuberculosis; and mortality rate. The HRCT findings were classified as miliary nodules; cavitation and centrilobular nodules with a tree-in-bud pattern; ground-glass attenuation with consolidation; mediastinal lymph node enlargement; or pleural effusion.

RESULTS

We evaluated 402 lung transplant recipients, 19 of whom developed pulmonary tuberculosis after transplantation. Among those 19 patients, the most common HRCT patterns were ground-glass attenuation with consolidation (in 42%); cavitation and centrilobular nodules with a tree-in-bud pattern (in 31.5%); and mediastinal lymph node enlargement (in 15.7%). Among the patients with cavitation and centrilobular nodules with a tree-in-bud pattern, the distribution was within the upper lobes in 66.6%. No pleural effusion was observed. Despite treatment, one-year mortality was 47.3%.

CONCLUSIONS

The predominant HRCT pattern was ground-glass attenuation with consolidation, followed by cavitation and centrilobular nodules with a tree-in-bud pattern. These findings are similar to those reported for immunocompetent patients with pulmonary tuberculosis and considerably different from those reported for AIDS patients with the same disease.

Chronic Airspace Diseases

Airspace disease can be acute or chronic and commonly present as consolidation or ground-glass opacity on chest imaging. Consolidation or ground-glass opacity occurs when alveolar air is replaced by fluid, pus, blood, cells, or other material. Airspace disease is considered chronic when it persists beyond 4-6 weeks after treatment. These can be secondary to certain infectious, inflammatory, or neoplastic conditions. Computed tomography of the chest is usually performed in this set of patients to identify characteristic imaging findings. Familiarity with the differential diagnosis and characteristic imaging findings for chronic airspace disease is very important for guiding patient's management in a timely fashion.

Sex influences the association between haemostasis and the extent of lung lesions in tuberculosis

Background

Worldwide tuberculosis (TB) reports show a male bias in morbidity; however, the differences in pathogenesis between men and women with TB, as well as the mechanisms associated with such differences, are poorly investigated. We hypothesized that comparison of the degree of lung injury and clinical indices of well-matched men and women with newly diagnosed TB, and statistical analysis of the correlation between these indices and the extent of lung lesions, can provide insights into the mechanism of gender bias in TB.

Methods

We evaluated the acid-fast bacilli grading of sputum samples and compiled computed tomography (CT) data of the age-matched, newly diagnosed male and female TB patients without history of smoking or comorbidities. Inflammatory biomarker levels and routine haematological and coagulation-associated parameters were compared. Binary logistic regression analysis was used to define the association between the indices and lung lesions, and the influence of sex adjustment.

Results

Women with TB have a longer delay in seeking healthcare than men after onset of the TB-associated symptoms. Men with TB have significantly more severe lung lesions (cavities and healing-associated features) and higher bacterial counts compared to women with TB. Scoring of the CT images before and after anti-TB treatment showed a faster response to therapy in women than in men. Coagulation- and platelet-associated indices were in models from multivariate regression analysis with groups of males or females with TB or in combination. In univariate regression analysis, lower lymphocyte counts were associated with both cavity and more bacterial counts, independent of sex, age and BMI. The association of international normalized ratios (INR), prothrombin times (PTs), mean platelet volumes (MPVs) and fibrinogen (FIB) level with lung lesions was mostly influenced by sex adjustment.

Conclusions

Sex influences the association between haemostasis and extent of TB lung lesions, which may be one mechanism involved in sex bias in TB pathogenesis.

Electronic supplementary material

The online version of this article (10.1186/s13293-018-0203-9) contains supplementary material, which is available to authorized users.

[Pulmonary tuberculosis: Radiological evolution of broncho-pulmonary lesions at the end of treatment]

OBJECTIVES

To describe the residual broncho-pulmonary lesions and evaluate the role of CT scanning at the end of treatment of pulmonary tuberculosis.

MATERIALS AND METHODS

Analysis of the initial and end of treatment CT scans of 56 patients with pulmonary tuberculosis according to a reading grid including parenchymatous and airways lesions. The CT data at the end of treatment were analysed in relation to the clinical and microbiological data, and the original CT scan.

RESULTS

Active lesions (thick walled cavities and/or centrilobular micronodules) persisted in 24 patients (43%) after a mean treatment period of 7 months. The persistence of these signs of activity was correlated with the initial presence of a cavitary syndrome (p=0.027), with predominant sub-segmentary bronchial involvement, with extensive micronodular spread (p=0.024) and with bronchiectasis (p=0.04). These residual lesions were not associated with an increased risk of relapse.

CONCLUSION

The persistence of signs of activity on the CT scan at the end of treatment of tuberculosis do not necessarily correspond to an absence of cure but to a radiological delay. This imaging is nevertheless useful to make an assessment of any subsequent changes in the bronchial tree and to estimate the risk of later complications.

The Pathogenesis of Tuberculosis: The Early Infiltrate of Post-primary (Adult Pulmonary) Tuberculosis: A Distinct Disease Entity

It has long been recognized that tuberculosis (TB) induces both protective and tissue damaging immune responses. This paper reviews nearly two centuries of evidence that protection and tissue damage are mediated by separate disease entities in humans. Primary TB mediates protective immunity to disseminated infection while post-primary TB causes tissue damage that results in formation of cavities. Both are necessary for continued survival of Mycobacterium tuberculosis (MTB). Primary TB has been extensively studied in humans and animals. Post-primary TB, in contrast, is seldom recognized or studied. It begins as an asymptomatic early infiltrate that may resolve or progress by bronchogenic spread to caseous pneumonia that either fragments to produce cavities or is retained to produce post-primary granulomas and fibrocaseous disease. Primary and post-primary TB differ in typical age of onset, histopathology, organ distribution, x-ray appearance, genetic predisposition, immune status of the host, clinical course and susceptibility to protection by BCG. MTB is a highly successful human parasite because it produces both primary and post-primary TB as distinct disease entities in humans. No animal reproduces this sequence of lesions. Recognition of these facts immediately suggests plausible solutions, animal models and testable hypotheses to otherwise inaccessible questions of the immunity and pathogenesis of TB.