Latent Tuberculosis Infection and COVID-19: Analysis of a Cohort of Patients from Careggi University Hospital (Florence, Italy).

Data regarding the relationship between coronavirus disease (COVID-19) and active or latent tuberculosis (TB) are discordant. We conducted a retrospective study examining the impact of latent tuberculosis infection (LTBI) on the clinical progression of COVID-19 patients. We selected 213 patients admitted with COVID-19 in a tertiary-level Italian hospital (February-December 2020), who underwent a QuantiFERON-TB test (QFT) and/or chest radiological exam. The population was divided into three groups: (i) QFT negative and without radiological TB sequelae (Neg); (ii) QFT positive and without radiological TB sequelae (Pos); (iii) radiological TB sequelae regardless of QFT result (Seq). In-hospital mortality and oro-tracheal intubation (OTI) showed significantly higher results in the Seq group (Seq 50% vs. Pos 13.3% vs. Neg 9.3%, p < 0.001; Seq 16.7% vs. Pos 6.7% vs. Neg 4.9%, p = 0.045). Considering the Pos and Seq groups' patients as the population with defined LTBI, in-hospital mortality (20/51, 39.2%) and OTI risk (7/51, 13.7%) were statistically higher with respect to patients without LTBI (in-hospital mortality: 15/162, 9.3%, p < 0.001; OTI risk: 8/162, 4.9%, p = 0.023), respectively. Multivariate analysis showed that radiological sequelae and the Charlson Comorbidity Index (CCI) were significantly associated with higher mortality rate; despite the higher CCI of Seq population, we cannot exclude the correlation between COVID-19 in-hospital mortality and the presence of radiological TB sequelae.

Primary Lymphoproliferative Lung Diseases: Imaging and Multidisciplinary Approach.

Lymphoproliferative lung diseases are a heterogeneous group of disorders characterized by primary or secondary involvement of the lung. Primary pulmonary lymphomas are the most common type, representing 0.5-1% of all primary malignancies of the lung. The radiological presentation is often heterogeneous and non-specific: consolidations, masses, and nodules are the most common findings, followed by ground-glass opacities and interstitial involvement, more common in secondary lung lymphomas. These findings usually show a prevalent perilymphatic spread along bronchovascular bundles, without a prevalence in the upper or lower lung lobes. An ancillary sign, such as a "halo sign", "reverse halo sign", air bronchogram, or CT angiogram sign, may be present and can help rule out a differential diagnosis. Since a wide spectrum of pulmonary parenchymal diseases may mimic lymphoma, a correct clinical evaluation and a multidisciplinary approach are mandatory. In this sense, despite High-Resolution Computer Tomography (HRCT) representing the gold standard, a tissue sample is needed for a certain and definitive diagnosis. Cryobiopsy is a relatively new technique that permits the obtaining of a larger amount of tissue without significant artifacts, and is less invasive and more precise than surgical biopsy.

Vascular tree-in-bud sign in Pulmonary Tumour Thrombotic Microangiopathy (PTTM): CT findings for a difficult radiological early antemortem diagnosis.

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Behçet's Disease: A Radiological Review of Vascular and Parenchymal Pulmonary Involvement.

Behcet's disease (BD) is a chronic systemic inflammatory disorder characterized by underlying chronic vasculitis of both large- and small-caliber vessels. Thoracic involvement in BD can occur with various types of manifestations, which can be detected with contrast-enhanced MSCT scanning. In addition, MR can be useful in diagnosis. Characteristic features are aneurysms of the pulmonary arteries that can cause severe hemoptysis and SVC thrombosis that manifests as SVC syndrome. Other manifestations are aortic and bronchial artery aneurysms, alveolar hemorrhage, pulmonary infarction, and rarely pleural effusion. Achieving the right diagnosis of these manifestations is important for setting the correct therapy and improving the patient's outcome.

A Home-Treatment Algorithm Based on Anti-inflammatory Drugs to Prevent Hospitalization of Patients With Early COVID-19: A Matched-Cohort Study (COVER 2).

Background and Aim: While considerable success has been achieved in the management of patients hospitalized with severe coronavirus disease 2019 (COVID-19), far less progress has been made with early outpatient treatment. We assessed whether the implementation of a home treatment algorithm-designed based on a pathophysiologic and pharmacologic rationale-and including non-steroidal anti-inflammatory drugs, especially relatively selective cyclooxygenase-2 inhibitors and, when needed, corticosteroids, anticoagulants, oxygen therapy and antibiotics-at the very onset of mild COVID-19 symptoms could effectively reduce hospital admissions. Methods: This fully academic, matched-cohort study evaluated outcomes in 108 consecutive consenting patients with mild COVID-19, managed at home by their family doctors between January 2021 and May 2021, according to the proposed treatment algorithm and in 108 age-, sex-, and comorbidities-matched patients on other therapeutic schedules (ClinicalTrials.gov: NCT04854824). The primary outcome was COVID-19-related hospitalization. Analyses were by intention-to-treat. Results: One (0.9%) patient in the "recommended" cohort and 12 (11.1%) in the "control" cohort were admitted to hospital (P = 0.0136). The proposed algorithm reduced the cumulative length of hospital stays by 85% (from 141 to 19 days) as well as related costs (from €60.316 to €9.058). Only 9.8 patients needed to be treated with the recommended algorithm to prevent one hospitalization event. The rate of resolution of major symptoms was numerically-but not significantly-higher in the "recommended" than in the "control" cohort (97.2 vs. 93.5%, respectively; P = 0.322). Other symptoms lingered in a smaller proportion of patients in the "recommended" than in the "control" cohort (20.4 vs. 63.9%, respectively; P < 0.001), and for a shorter period. Conclusion: The adoption of the proposed outpatient treatment algorithm during the early, mild phase of COVID-19 reduced the incidence of subsequent hospitalization and related costs.

Systemic Emergencies in COVID-19 Patient: A Pictorial Review.

Since the first report of the outbreak in Wuhan, China in December 2019, as of 1 September 2021, the World Health Organization has confirmed more than 239 million cases of the novel coronavirus (SARS-CoV-2) infectious disease named coronavirus disease 2019 (COVID-19), with more than 4.5 million deaths. Although SARS-CoV-2 mainly involves the respiratory tract, it is considered to be a systemic disease. Imaging plays a pivotal role in the diagnosis of all manifestations of COVID-19 disease, as well as its related complications. The figure of the radiologist is fundamental in the management and treatment of the patient. The authors try to provide a systematic approach based on an imaging review of major multi-organ manifestations of this infection.

Acute Pulmonary Embolism: Prognostic Role of Computed Tomography Pulmonary Angiography (CTPA).

Computed Tomography Pulmonary Angiography (CTPA) is considered the gold standard diagnostic technique in patients with suspected acute pulmonary embolism in emergency departments. Several studies have been conducted on the predictive value of CTPA on the outcomes of pulmonary embolism (PE). The purpose of this article is to provide an updated review of the literature reporting imaging parameters and quantitative CT scores to predict the severity of PE.

CT findings of non-neoplastic central airways diseases.

Non-neoplastic lesions of central airways are uncommon entities with different etiologies, with either focal or diffuse involvement of the tracheobronchial tree. Clinical symptoms of non-neoplastic tracheobronchial diseases are non-specific, and diagnosis is difficult, especially in the early stages. Three-dimensional computed tomography (3D-CT) is an evaluable tool as it allows to assess and characterize tracheobronchial wall lesions and meanwhile it enables the evaluation of airways surrounding structures. Multiplanar reconstructions (MPR), minimum intensity projections (MinIP), and 3D Volume Rendering (VR) (in particular, virtual bronchoscopy) also provide information on the site and of the length of airway alterations. This review will be discussed about (1) primary airway disorders, such as relapsing polychondritis, tracheobronchophathia osteochondroplastica, and tracheobronchomegaly, (2) airway diseases, related to granulomatosis with polyangiitis, Chron's disease, Behcet's disease, sarcoidosis, amyloidosis, infections, intubation and transplantation, (3) tracheobronchial malacia, and (4) acute tracheobronchial injury. 3D-CT findings, especially with MPR and 3D VR reconstructions, allows us to evaluate tracheobronchial disease morphologically in detail.

Preliminary Report on Computed Tomography Radiomics Features as Biomarkers to Immunotherapy Selection in Lung Adenocarcinoma Patients.

PURPOSE: To assess the efficacy of radiomics features obtained by computed tomography (CT) examination as biomarkers in order to select patients with lung adenocarcinoma who would benefit from immunotherapy. METHODS: Seventy-four patients (median age 63 years, range 42-86 years) with histologically confirmed lung cancer who underwent immunotherapy as first- or second-line therapy and who had baseline CT studies were enrolled in this approved retrospective study. As a control group, we selected 50 patients (median age 66 years, range 36-86 years) from 2005 to 2013 with histologically confirmed lung adenocarcinoma who underwent chemotherapy alone or in combination with targeted therapy. A total of 573 radiomic metrics were extracted: 14 features based on Hounsfield unit values specific for lung CT images; 66 first-order profile features based on intensity values; 43 second-order profile features based on lesion shape; 393 third-order profile features; and 57 features with higher-order profiles. Univariate and multivariate statistical analysis with pattern recognition approaches and the least absolute shrinkage and selection operator (LASSO) method were used to assess the capability of extracted radiomics features to predict overall survival (OS) and progression free survival (PFS) time. RESULTS: A total of 38 patients (median age 61; range 41-78 years) with confirmed lung adenocarcinoma and subjected to immunotherapy satisfied inclusion criteria, and 50 patients in a control group were included in the analysis The shift in the center of mass of the lesion due to image intensity was significant both to predict OS in patients subjected to immunotherapy and to predict PFS in patients subjected to immunotherapy and in patients in the control group. With univariate analysis, low diagnostic accuracy was reached to stratify patients based on OS and PFS time. Regarding multivariate analysis, considering the robust (two morphological features, three textural features and three higher-order statistical metrics) application of the LASSO approach and all patients, a support vector machine reached the best results for stratifying patients based on OS (area under curve (AUC) of 0.89 and accuracy of 81.6%). Alternatively, considering the robust predictors (six textural features and one higher-order statistical metric) and application of the LASSO approach including all patients, a decision tree reached the best results for stratifying patients based on PFS time (AUC of 0.96 and accuracy of 94.7%). CONCLUSIONS: Specific radiomic features could be used to select patients with lung adenocarcinoma who would benefit from immunotherapy because a subset of imaging radiomic features useful to predict OS or PFS time were different between the control group and the immunotherapy group.

Behçet disease in Emergency Department: a rare case presenting with haemoptysis and massive pulmonary arterial aneurysms.

Behçet disease (BD) is a systemic disorder caused by underlying vasculitis of unknown origin. In this paper we present a case of a 26-year-old male patient who was admitted at our Emergency Department with massive haemoptysis due to pulmonary arterial involvement in BD. The discussion of this case helps to remember that BD is the main cause of aneurysm of the pulmonary arteries and a cause of haemoptysis in young patients. Therefore, the radiologist plays a key role in the identification of intrathoracic alterations with chest computed tomography. The knowledge of clinical manifestations and distinctive elements of BD allow an accurate diagnosis and let the patient to be directed towards an appropriate treatment, in order to avoid the onset of life-threatening complications.

A simple, home-therapy algorithm to prevent hospitalisation for COVID-19 patients: A retrospective observational matched-cohort study.

BACKGROUND: Effective home treatment algorithms implemented based on a pathophysiologic and pharmacologic rationale to accelerate recovery and prevent hospitalisation of patients with early coronavirus disease 2019 (COVID-19) would have major implications for patients and health system. METHODS: This academic, matched-cohort study compared outcomes of 90 consecutive consenting patients with mild COVID-19 treated at home by their family physicians between October 2020 and January 2021 in Northern and Central Italy, according to the proposed recommendation algorithm, with outcomes for 90 age-, sex-, and comorbidities-matched patients who received other therapeutic regimens. Primary outcome was time to resolution of major symptoms. Secondary outcomes included prevention of hospitalisation. Analyses were by intention-to-treat. FINDINGS: All patients achieved complete remission. The median [IQR] time to resolution of major symptoms was 18 [14-23] days in the 'recommended schedule' cohort and 14 [7-30] days in the matched 'control' cohort (p = 0·033). Other symptoms persisted in a lower percentage of patients in the 'recommended' than in the 'control' cohort (23·3% versus 73·3%, respectively, p<0·0001) and for a shorter period (p = 0·0107). Two patients in the 'recommended' cohort were hospitalised compared to 13 (14·4%) controls (p = 0·0103). The prevention algorithm reduced the days and cumulative costs of hospitalisation by >90%. INTERPRETATION: Implementation of an early home treatment algorithm failed to accelerate recovery from major symptoms of COVID-19, but reduced the risk of hospitalisation and related treatment costs. Given the study design, additional research would be required to consolidate the proposed treatment recommendations. FUNDING: Fondazione Cav.Lav. Carlo Pesenti.

Prognostic value of CT pulmonary angiography parameters in acute pulmonary embolism.

OBJECTIVES: Computed tomographic pulmonary angiography (CTPA) is the first-line test in acute pulmonary embolism (APE) diagnostic algorithm, but its correlation with short-term outcome remains not clear at all. The aim is to determine whether CTPA findings can predict 30-day mortality of patients with APE in Emergency Department. METHODS: This retrospective monocentric study involved 780 patients with APE diagnosed at the Emergency Department of our institution (period 2010-2019). These CTPA findings were evaluated: embolic obstruction burden score (Qanadli score), common pulmonary artery trunk diameter, right-to-left ventricular ratio, azygos vein and coronary sinus diameters. Comorbidities and fatal/nonfatal adverse outcomes within 30 days were recorded. Troponin I values were correlated with angiographic parameters with multiple logistic regression analysis. RESULTS: The all-cause and APE-related 30-day mortality rates were 5.9% and 3.6%, respectively. Patients who died within 30 days were older with higher prevalence rates of malignancy. Qanadli score and all CTPA parameters correlate with Troponin I level and the presence of RVD at echocardiography (p values < 0.0001). Instead, RV/LV ratio and coronary sinus diameter correlate with 30-day mortality (p values < 0.05). At the multivariate logistic regression analysis, only coronary sinus and RVD remained significant with an HR = 2.5 (95% CI 1.1-5.6) and HR = 1.9 (95% CI 0.95-3.7), respectively. CONCLUSION: CTPA quantification of right ventricular strain is an accurate predictor of 30-day mortality. In particular, it seems that a dilated coronary sinus (>9 mm) has an additional prognostic value in association with echocardiographic signs of right-heart disfunction and high Troponin I levels.

Ground-glass opacity (GGO): a review of the differential diagnosis in the era of COVID-19.

Thoracic imaging is fundamental in the diagnostic route of Coronavirus disease 2019 (COVID-19) especially in patients admitted to hospitals. In particular, chest computed tomography (CT) has a key role in identifying the typical features of the infection. Ground-glass opacities (GGO) are one of the main CT findings, but their presence is not specific for this viral pneumonia. In fact, GGO is a radiological sign of different pathologies with both acute and subacute/chronic clinical manifestations. In the evaluation of a subject with focal or diffuse GGO, the radiologist has to know the patient's medical history to obtain a valid diagnostic hypothesis. The authors describe the various CT appearance of GGO, related to the onset of symptoms, focusing also on the ancillary signs that can help radiologist to obtain a correct and prompt diagnosis.

Quantitative imaging decision support (QIDSTM) tool consistency evaluation and radiomic analysis by means of 594 metrics in lung carcinoma on chest CT scan.

OBJECTIVE: To evaluate the consistency of the quantitative imaging decision support (QIDSTM) tool and radiomic analysis using 594 metrics in lung carcinoma on chest CT scan. MATERIALS AND METHODS: We included, retrospectively, 150 patients with histologically confirmed lung cancer who underwent chemotherapy and baseline and follow-ups CT scans. Using the QIDSTM platform, 3 radiologists segmented each lesion and automatically collected the longest diameter and the density mean value. Inter-observer variability, Bland Altman analysis and Spearman's correlation coefficient were performed. QIDSTM tool consistency was assessed in terms of agreement rate in the treatment response classification. Kruskal Wallis test and the least absolute shrinkage and selection operator (LASSO) method with 10-fold cross validation were used to identify radiomic metrics correlated with lesion size change. RESULTS: Good and significant correlation was obtained between the measurements of largest diameter and of density among the QIDSTM tool and the radiologists measurements. Inter-observer variability values were over 0.85. HealthMyne QIDSTM tool quantitative volumetric delineation was consistent and matched with each radiologist measurement considering the RECIST classification (80-84%) while a lower concordance among QIDSTM and the radiologists CHOI classification was observed (58-63%). Among 594 extracted metrics, significant and robust predictors of RECIST response were energy, histogram entropy and uniformity, Kurtosis, coronal long axis, longest planar diameter, surface, Neighborhood Grey-Level Different Matrix (NGLDM) dependence nonuniformity and low dependence emphasis as Volume, entropy of Log(2.5 mm), wavelet energy, deviation and root man squared. CONCLUSION: In conclusion, we demonstrated that HealthMyne quantitative volumetric delineation was consistent and that several radiomic metrics extracted by QIDSTM were significant and robust predictors of RECIST response.

Chest X-ray in the emergency department during COVID-19 pandemic descending phase in Italy: correlation with patients' outcome.

PURPOSE: The aims of our study are: (1) to estimate admission chest X-ray (CXR) accuracy during the descending phase of pandemic; (2) to identify specific CXR findings strictly associated with COVID-19 infection; and (3) to correlate lung involvement of admission CXR with patients' outcome. MATERIALS AND METHODS: We prospectively evaluated the admission CXR of 327 patients accessed to our institute during the Italian pandemic descending phase (April 2020). For each CXR were searched ground glass opacification (GGO), consolidation (CO), reticular-nodular opacities (RNO), nodules, excavations, pneumothorax, pleural effusion, vascular congestion and cardiac enlargement. For lung alterations was defined the predominance (upper or basal, focal or diffuse, central or peripheric, etc.). Then radiologists assessed whether CXRs were suggestive or not for COVID-19 infection. For COVID-19 patients, a prognostic score was applied and correlated with the patients' outcome. RESULTS: CXR showed 83% of specificity and 60% of sensitivity. GGO, CO, RNO and a peripheric, diffuse and basal prevalence showed good correlation with COVID-19 diagnosis. A logistic regression analysis pointed out GGO and a basal or diffuse distribution as independent predictors of COVID-19 diagnosis. The prognostic score showed good correlation with the patients' outcome. CONCLUSION: In our study, admission CXR showed a fair specificity and a good correlation with patients' outcome. GGO and others CXR findings showed a good correlation with COVID-19 diagnosis; besides GGO a diffuse or bibasal distribution resulted in independent variables highly suggestive for COVID-19 infection thus enabling radiologists to signal to clinicians radiologically suspect patients during the pandemic descending phase.

Exogenous lipoid pneumonia: when radiologist makes the difference.

PURPOSE: To report high-resolution CT (HRCT) findings in our group of patients with exogenous lipoid pneumonia (ELP), confirmed with histopathological findings and clinical-anamnestic data, in order to describe the most common radiological patterns of this rare disorder. MATERIALS AND METHODS: In this retrospective study, HRCT of 10 patients with ELP were evaluated by three radiologists. Diagnosis of ELP was made through CT, bronchiolo-alveolar lavage (BAL) and a pneumological examination associated with an accurate medical anamnesis. Five patients had a histologically proven ELP, through lung biopsy. All patients had a chronic exposition to substances made of animal fat or mineral/vegetable oils. RESULTS: In our cohort of patients with ELP, the following parenchymal patterns were observed: 8/10 patients had lung consolidation with adipose density (attenuation values < - 40 HU); 10/10 patients had multiple areas of ground glass opacity; 6/10 patients had smooth thickening of interlobular septa and ground glass opacities ("crazy-paving" pattern); 2/10 patients presented nodules > 2.5 cm with spiculated margins (tumor-like); 5/10 patients showed reactive lymph nodes enlargement. The oldest lesions were characterized by bronchiectasis and fibrosis around the lipidic consolidations. CONCLUSION: Pulmonary alterations found in HRCT exams can be confused with other lung diseases (especially lung tumors) and they are always a challenge even for the most experienced radiologist. In our experience, although non-specific, consolidation areas with low HU values and crazy-paving pattern are frequently associated in ELP. These characteristics should alert the radiologist to consider ELP among the possible differential diagnoses, always correlating the results of CT examination with appropriate clinical-laboratory evaluations and an accurate anamnesis.

Chest X-ray in new Coronavirus Disease 2019 (COVID-19) infection: findings and correlation with clinical outcome.

AIM: The purpose of this study is to describe the main chest radiological features (CXR) of COVID-19 and correlate them with clinical outcome. MATERIALS AND METHODS: This is a retrospective study involving patients with clinical-epidemiological suspect of COVID-19 infection, who performed CXRs at the emergency department (ED) of our University Hospital from March 1 to March 31, 2020. All patients performed RT-PCR nasopharyngeal and throat swab, CXR at the ED and clinical-epidemiological data. RT-PCR results were considered the reference standard. The final outcome was expressed as discharged or hospitalized patients into a medicine department or intensive care unit (ICU). RESULTS: Patients that had a RT-PCR positive for COVID-19 infection were 234 in total: 153 males (65.4%) and 81 females (34.6%), with a mean age of 66.04 years (range 18-97 years). Thirteen CXRs were negative for radiological thoracic involvement (5.6%). The following alterations were more commonly observed: 135 patients with lung consolidations (57.7%), 147 (62.8%) with GGO, 55 (23.5%) with nodules and 156 (66.6%) with reticular-nodular opacities. Patients with consolidations and GGO coexistent in the same radiography were 35.5% of total. Peripheral (57.7%) and lower zone distribution (58.5%) were the most common predominance. Moreover, bilateral involvement (69.2%) was most frequent than unilateral one. Baseline CXR sensitivity in our experience is about 67.1%. The most affected patients were especially males in the age group 60-79 years old (45.95%, of which 71.57% males). RALE score was slightly higher in male than in female patients. ANOVA with Games-Howell post hoc showed significant differences of RALE scores for group 1 vs 3 (p < 0.001) and 2 vs 3 (p = 0.001). Inter-reader agreement in assigning RALE score was very good (ICC: 0.92-with 95% confidence interval 0.88-0.95). CONCLUSION: In COVID-19, CXR shows patchy or diffuse reticular-nodular opacities and consolidation, with basal, peripheral and bilateral predominance. In our experience, baseline CXR had a sensitivity of 68.1%. The RALE score can be used in the emergency setting as a quantitative method of the extent of SARS-CoV-2 pneumonia, correlating with an increased risk of ICU admission.

Radiological Patterns of Lung Involvement in Inflammatory Bowel Disease.

Inflammatory bowel disease (IBD) is a form of chronic inflammation of the gastrointestinal tract, including two major entities: ulcerative colitis and Crohn's disease. Although intestinal imaging of IBD is well known, imaging of extraintestinal manifestations is not extensively covered. In particular, the spectrum of IBD-associated or related changes in the chest is broad and may mimic other conditions. The common embryonic origin of intestine and lungs from the foregut, autoimmunity, smoking, and bacterial translocation from the colon may all be involved in the pathogenesis of these manifestations in IBD patients. Chest involvement in IBD can present concomitant with or years after the onset of the bowel disease even postcolectomy and can affect more than one thoracic structure. The purpose of the present paper is to present the different radiological spectrum of IBD-related chest manifestations, including lung parenchyma, airways, serosal surfaces, and pulmonary vasculature. The most prevalent and distinctive pattern of respiratory involvement is large airway inflammation, followed by lung alterations. Pulmonary manifestations are mainly detected by pulmonary function tests and high-resolution computed tomography (HRCT). It is desirable that radiologists know the various radiological patterns of possible respiratory involvement in such patients, especially at HRCT. It is essential for radiologists to work in multidisciplinary teams in order to establish the correct diagnosis and treatment, which rests on corticosteroids at variance with any other form of bronchiectasis.

Lobar Collapse Therapy Using Endobronchial Valves as a New Complementary Approach to Treat Cavities in Multidrug-Resistant Tuberculosis and Difficult-to-Treat Tuberculosis: A Case Series.

BACKGROUND: The poor treatment outcomes of multidrug-resistant tuberculosis (TB) and the emergence of extensively drug-resistant TB and extremely and totally drug-resistant TB highlight the urgent need for new antituberculous drugs and other adjuvant treatment approaches. OBJECTIVES: We have treated cavitary tuberculosis by the application of endobronchial one-way valves (Zephyr®; Pulmonx Inc., Redwood City, Calif., USA) to induce lobar volume reduction as an adjunct to drug treatment. This report describes the feasibility, effectiveness and safety of the procedure. METHODS: Patients with severe lung destruction, one or more cavities or those who were ineligible for surgical resection and showed an unsatisfactory response to standard drug treatments were enrolled. During bronchoscopy, endobronchial valves were implanted in the lobar or segmental bronchi in order to induce atelectasis and reduce the cavity size. RESULTS: Four TB patients and 1 patient with atypical mycobacteriosis were treated. The mean patient age was 52.6 years. Complete cavity collapses were observed on CT scans in 4 of the 5 cases. All patients showed improvements in their clinical status, and sputum smears became negative within 3-5 months. There were no severe short- or long-term complications. The valves were removed in 3 of the 5 patients after 8 months on average; there was no relapse after 15 months of follow-up. CONCLUSION: These data suggest that endobronchial valves are likely to be useful adjuncts to the treatment of therapeutically difficult patients. More data are required to confirm our findings.