CT findings in severe thoracic sarcoidosis

Central Bronchial Deformity in Pulmonary Sarcoidosis: A Finding Suggestive of an Upper Lobe Fibrotic Phenotype on Chest Images

RATIONALE AND OBJECTIVES

Bronchial and lung parenchymal structural remodeling may occur due to disease progression in patients with pulmonary sarcoidosis; however, its mechanisms remain unclear. Central bronchial deformity (CBD) associated with shrinkage in the upper lobe (SUL) is often observed in such patients. This study aimed to examine the association between CBD and structural remodeling to identify features indicating disease severity on chest images.

MATERIALS AND METHODS

This retrospective cohort study included 72 patients with pulmonary sarcoidosis, excluding patients with only bilateral hilar lymphadenopathy. The participants were divided into with and without CBD groups to examine the association between CBD and other structural remodeling, including SUL, cyst and/or low attenuation area-like emphysema (Cyst/LAA), pleural/sub-pleural thickening (PT), and traction bronchiectasis (TrBE), in the upper lobe on chest images. The association of CBD phenotype with respiratory dysfunction was also examined.

RESULTS

CBD was highly associated with SUL (81.4% vs. 8.9%), Cyst/LAA (44.4% vs. 6.7%), and PT (59.2% vs. 3.7%). The respective odds ratios in the univariable and multivariable analyses were as follows: SUL, 45.1 and 39.9; Cyst/LAA, 11.2 and 14.2; and PT, 64.0 and 68.7. TrBE was frequently associated with CBD (22.25% vs. 4.4%); the odds ratio was 6.14 in the univariable analysis. Furthermore, participants with CBD exhibited lower %FVC and %DLCO.

CONCLUSION

CBD is significantly associated with lung remodeling (SUL, Cyst/LAA, TrBE, and PT) and respiratory dysfunction. CBD may be a crucial clinical phenotype to identify upper lobe fibrotic changes.

Imaging of Pulmonary Sarcoidosis-A Review

Sarcoidosis is the classic multisystem granulomatous disease. First reported as a disorder of the skin, it is now clear that, in the overwhelming majority of patients with sarcoidosis, the lungs will bear the brunt of the disease. This review explores some of the key concepts in the imaging of pulmonary sarcoidosis: the wide array of typical (and some of the less common) findings on high-resolution computed tomography (HRCT) are reviewed and, with this, the concept of morphologic/HRCT phenotypes is discussed. The pathophysiologic insights provided by HRCT through studies where morphologic abnormalities and pulmonary function tests are compared are evaluated. Finally, this review outlines the important contribution of HRCT to disease monitoring and prognostication.

Sarcoidosis Associated with Enlarged Mediastinal Lymph Nodes with the Detection of Streptococcus gordonii and Cutibacterium acnes Using a Clone Library Method

A 77-year-old Japanese woman with mediastinal lymphadenopathy and uveitis was diagnosed with sarcoidosis. The bacterial flora in biopsied samples from mediastinal lymph nodes was analyzed using a clone library method with Sanger sequencing of the 16S rRNA gene, and Streptococcus gordonii (52 of 71 clones) and Cutibacterium acnes (19 of 71 clones) were detected. No previous study has conducted a bacterial floral analysis using the Sanger method for the mediastinal lymph node in sarcoidosis, making this case report the first to document the presence of S. gordonii and C. acnes in the mediastinal lymph node of a patient with sarcoidosis.

Pulmonary sarcoidosis: A comprehensive review: Past to present

Sarcoidosis is a sterile non-necrotizing granulomatous disease without known causes that can involve multiple organs with a predilection for the lung and thoracic lymph nodes. Worldwide it is estimated to affect 2-160/100,000 people and has a mortality rate over 5 years of approximately 7%. For sarcoidosis patients, the cause of death is due to sarcoid in 60% of the cases, of which up to 80% are from advanced cardiopulmonary failure (pulmonary hypertension and respiratory microbial infections) in all races except in Japan were greater than 70% of the sarcoidosis deaths are due to cardiac sarcoidosis. Scadding stages for pulmonary sarcoidosis associates with clinical outcomes. Stages I and II have radiographic remission in approximately 30%-80% of cases. Stage III only has a 10%-40% chance of resolution, while stage IV has no change of resolution. Up to 40% of pulmonary sarcoidosis patients progress to stage IV disease with lung parenchyma fibroplasia, bronchiectasis with hilar retraction and fibrocystic disease. These patients are at highest risk for the development of precapillary pulmonary hypertension, which may occur in up to 70% of these patients. Sarcoid patients with pre-capillary pulmonary hypertension can respond to targeted pulmonary arterial hypertension medications. Stage IV fibrocytic sarcoidosis with significant pulmonary physiologic impairment, >20% fibrosis on HRCT or pre-capillary pulmonary hypertension have the highest risk of mortality, which can be >40% at 5-years. First line treatment for patients who are symptomatic (cough and dyspnea) with parenchymal infiltrates and abnormal pulmonary function testing (PFT) is oral glucocorticoids, such as prednisone with a typical starting dose of 20-40 mg daily for 2 weeks to 2 months. Prednisone can be tapered over 6-18 months if symptoms, spirometry, PFTs, and radiographs improve. Prolonged prednisone may be required to stabilize disease. Patients requiring prolonged prednisone ≥10 mg/day or those with adverse effects due to glucocorticoids may be prescribed second and third line treatements. Second and third line treatments include immunosuppressive agents (e.g., methotrexate and azathioprine) and anti-tumor necrosis factor (TNF) medication; respectively. Effective treatments for advanced fibrocystic pulmonary disease are being explored. Despite different treatments, relapse rates range from 13% to 75% depending on the stage of sarcoid, number of organs involved, socioeconomic status, and geography. CONCLUSION: The mortality rate for sarcoidosis over a 5 year follow up is approximately 7%. Unfortunately, 10%-40% of patients with sarcoidosis develop progressive pulmonary disease, and >60% of deaths resulting from sarcoidosis are due to advance cardiopulmonary disease. Oral glucocorticoids are the first line treatment, while methotrexate and azathioprine are considered second and anti-TNF agents are third line treatments that are used solely or as glucocorticoid sparing agents for symptomatic extrapulmonary or pulmonary sarcoidosis with infiltrates on chest radiographs and abnormal PFT. Relapse rates have ranged from 13% to 75% depending on the population studied.

Diagnosis and Treatment of Pulmonary Sarcoidosis: A Review

IMPORTANCE

Sarcoidosis is an inflammatory granulomatous disease of unknown cause that affects an estimated 2 to 160 people per 100 000 worldwide and can involve virtually any organ. Approximately 10% to 30% of patients with sarcoidosis develop progressive pulmonary disease.

OBSERVATION

Among patients with pulmonary sarcoidosis, the rate of spontaneous remission without serious sequelae ranges from 10% to 82%. However, lung disease progression occurs in more than 10% of patients and can result in fibrocystic architectural distortion of the lung, which is associated with a mortality rate of 12% to 18% within 5 years. Overall, the mortality rate for sarcoidosis is approximately 7% within a 5-year follow-up period. Worldwide, more than 60% of deaths from sarcoidosis are due to pulmonary involvement; however, more than 70% of deaths from sarcoidosis are due to cardiac involvement in Japan. Up to 70% of patients with advanced pulmonary sarcoidosis develop precapillary pulmonary hypertension, which is associated with a 5-year mortality rate of approximately 40%. Patients with sarcoidosis and precapillary pulmonary hypertension should be treated with therapies such as phosphodiesterase inhibitors and prostacyclin analogues. Although optimal doses of oral glucocorticoids for pulmonary sarcoidosis are unknown, oral prednisone typically starting at a dose of 20 mg/d to 40 mg/d for 2 to 6 weeks is recommended for patients who are symptomatic (cough, dyspnea, and chest pain) and have parenchymal infiltrates and abnormal pulmonary function test results. Oral glucocorticoids can be tapered over 6 to 18 months if symptoms, pulmonary function test results, and radiographs improve. Prolonged use of oral glucocorticoids may be required to control symptoms and stabilize disease. Patients without adequate improvement while receiving a dose of prednisone of 10 mg/d or greater or those with adverse effects due to glucocorticoids may be prescribed immunosuppressive agents, such as methotrexate, azathioprine, or an anti-tumor necrosis factor medication, either alone or with glucocorticoids combined with appropriate microbial prophylaxis for Pneumocystis jiroveci and herpes zoster. Effective treatments are not available for advanced fibrocystic pulmonary disease.

CONCLUSIONS AND RELEVANCE

Sarcoidosis has a mortality rate of approximately 7% within a 5-year follow-up period. More than 10% of patients with pulmonary sarcoidosis develop progressive disease and more than 60% of deaths are due to advanced pulmonary sarcoidosis. Oral glucocorticoids with or without another immunosuppressive agent are the first-line therapy for symptomatic patients with abnormal pulmonary function test results and lung infiltrates. Patients with sarcoidosis and precapillary pulmonary hypertension should be treated with therapies such as phosphodiesterase inhibitors and prostacyclin analogues.

Riociguat for Sarcoidosis-Associated Pulmonary Hypertension: Results of a 1-Year Double-Blind, Placebo-Controlled Trial

BACKGROUND

Riociguat is effective in delaying the time to clinical worsening (TCW) in patients with groups 1 and 4 pulmonary hypertension.

RESEARCH QUESTION

Is riociguat more effective than placebo in prolonging TCW in sarcoidosis-associated pulmonary hypertension (SAPH)?

STUDY DESIGN AND METHODS

This was a double-blind placebo-controlled trial. Patients with SAPH confirmed by right heart catheterization were randomized 1:1 to riociguat or placebo. Patients underwent 6-min walk distance (6MWD) and spirometry testing every 8 weeks. The primary end point was TCW, which was defined by the time to the first of the following: (1) all-cause mortality, (2) need for hospitalization because of worsening cardiopulmonary status attributable to progression of disease, (3) > 50 m decrease in the 6MWD test, or (4) worsening of World Health Organization functional class.

RESULTS

A total of 16 patients were randomized to riociguat (n = 8) or placebo (n = 8). No difference was found in pulmonary artery mean, pulmonary vascular resistance, initial 6MWD, or FVC between the two groups. Five of eight patients who received placebo met TCW criteria, whereas none of the patients who received riociguat experienced a qualifying event. By log-rank analysis, patients who received riociguat were in the study for a significantly longer period (χ ² = 6.259; P = .0124). The 6MWD decreased in the placebo group (median, -55.9 m; range, -176.8 to 60 m), but rose in the riociguat group (median, +42.7 m; range, -7.5 to +91.4 m; P = .0149), with a placebo-corrected difference of 94 m (P < .01). Four of eight patients who received riociguat, but only 1 of 8 patients who received placebo, showed a > 30-m improvement in 6MWD (P > .05). No significant adverse events associated with riociguat occurred.

INTERPRETATION

Over the 1 year of the study, riociguat was effective in preventing clinical worsening and improving exercise capacity in patients with SAPH.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT02625558; URL: www.clinicaltrials.gov.

Advanced Pulmonary Sarcoidosis

At least 5% of sarcoidosis patients die from their disease, usually from advanced pulmonary sarcoidosis. The three major problems encountered in advanced pulmonary sarcoidosis are pulmonary fibrosis, pulmonary hypertension, and respiratory infections. Pulmonary fibrosis is the result of chronic inflammation, but other factors including abnormal wound healing may be important. Sarcoidosis-associated pulmonary hypertension (SAPH) is multifactorial including parenchymal fibrosis, vascular granulomas, and hypoxia. Respiratory infections can be cause by structural changes in the lung and impaired immunity due to sarcoidosis or therapy. Anti-inflammatory therapy alone is not effective in most forms of advanced pulmonary sarcoidosis. New techniques, including high-resolution computer tomography and 18F-fluorodeoxyglucose positron emission tomography (PET) have proved helpful in identifying the cause of advanced disease and directing specific therapy.

Radiographic and Histopathologic Features in Sarcoidosis: A Pictorial Display

Sarcoidosis is a multisystemic granulomatous disorder that can affect virtually any organ. However, pulmonary and thoracic lymph node involvement predominates; abnormalities on chest radiographs are present in 80 to 90% of patients with sarcoidosis. High-resolution computed tomographic (HRCT) scans are superior to chest X-rays in assessing extent of disease, and some CT features may discriminate an active inflammatory component (which may be amenable to therapy) from fibrosis (for which therapy is not indicated). Typical findings on HRCT include micronodules, perilymphatic and bronchocentric distribution, perihilar opacities, and varying degrees of fibrosis. Less common findings on CT include mass-like or alveolar opacities, miliary opacities, mosaic attenuation, honeycomb cysts, and cavitation. With progressive disease, fibrosis, architectural distortion, upper lobe volume loss with hilar retraction, coarse linear bands, cysts, and bullae may be observed. We discuss the salient CT findings in patients with sarcoidosis (with a major focus on pulmonary features) and present classical radiographic and histopathological images of a few extrapulmonary sites.

New advances in the management of pulmonary sarcoidosis

Sarcoidosis is a highly variable granulomatous multisystem syndrome. It affects individuals in the prime years of life; both the frequency and severity of sarcoidosis are greater in economically disadvantaged populations. The diagnosis, assessment, and management of pulmonary sarcoidosis have evolved as new technologies and therapies have been adopted. Transbronchial needle aspiration guided by endobronchial ultrasound has replaced mediastinoscopy in many centers. Advanced imaging modalities, such as fluorodeoxyglucose positron emission tomography scanning, and the widespread availability of magnetic resonance imaging have led to more sensitive assessment of organ involvement and disease activity. Although several new insights about the pathogenesis of sarcoidosis exist, no new therapies have been specifically developed for use in the disease. The current or proposed use of immunosuppressive medications for sarcoidosis has been extrapolated from other disease states; various novel pathways are currently under investigation as therapeutic targets. Coupled with the growing recognition of corticosteroid toxicities for managing sarcoidosis, the use of corticosteroid sparing anti-sarcoidosis medications is likely to increase. Besides treatment of granulomatous inflammation, recognition and management of the non-granulomatous complications of pulmonary sarcoidosis are needed for optimal outcomes in patients with advanced disease.

Why do people die from pulmonary sarcoidosis?

PURPOSE OF REVIEW

In sarcoidosis, the design and validation of an appropriate risk stratification strategy is hampered by the considerable variability in initial presentation, disease evolution, and outcome. Although spontaneous resolution of the disease is described in a large proportion of patients, approximately 20-30% would present with chronic or progressive lung disease that has been associated with morbidity and mortality. Higher morbidity and mortality can be related to both the disease severity and extent as well as its treatments. We review the utility of integration of clinical, pathological, and radiological features of pulmonary sarcoidosis to detect pulmonary sarcoidosis patient at risk of developing severe, fibrotic lung disease.

RECENT FINDINGS

Recently published studies suggested a mortality rate of 11-14 per 1000 person-years. Demographic characteristics such as age, sex, and race may play a role but conflicting evidence are reported depending on the origin of the population. To date, there are no tools that can reliably predict the exact group of pulmonary sarcoidosis patients to progress to fibrosis. Imaging contributes significantly to the diagnosis and management of patients with sarcoidosis as it can provide useful information regarding the discrimination between reversible and irreversible disease, the extent of the parenchymal damage and the presence of possible complications. Symptoms and lung function tests are the rest of the key determinants and their change over time should be considered.

SUMMARY

This review concentrates on the definition of advanced pulmonary sarcoidosis and determinants of mortality in the pulmonary sarcoidosis group of patients.

High-Risk Sarcoidosis. Current Concepts and Research Imperatives

Sarcoidosis is a disease with heterogeneous manifestations and outcomes, varying in part on the basis of organ involvement. Specifically, patients with sarcoidosis at risk for poor outcomes include individuals with treatment-resistant pulmonary sarcoidosis, including fibrotic pulmonary disease and pulmonary hypertension, as well as those with cardiac, neurologic, and multiorgan disease. The limited but available data relating to these patients with high-risk sarcoidosis, defined as those patients with presentations requiring medical intervention to avoid progressive disability or premature death, was evaluated as part of the National Heart, Lung, and Blood Institute's workshop to improve understanding of these disease manifestations. In particular, knowledge gaps that preclude a greater understanding of the pathogenesis and management of these severe sarcoidosis clinical phenotypes were identified in the workshop. Research strategies are proposed to address critical knowledge gaps that would further our understanding of these disease manifestations and enhance the care of these patients.

Short-Term Particulate Air Pollution Exposure is Associated with Increased Severity of Respiratory and Quality of Life Symptoms in Patients with Fibrotic Sarcoidosis

This study aimed to determine if short-term exposure to particulate matter (PM_2.5) and ozone (O₃) is associated with increased symptoms or lung function decline in fibrotic sarcoidosis. Sixteen patients with fibrotic sarcoidosis complicated by frequent exacerbations completed pulmonary function testing and questionnaires every three months for one year. We compared 7-, 10-, and 14-day average levels of PM_2.5 and O₃ estimated at patient residences to spirometry (forced expiratory volume in 1 s (FEV1), to forced vital capacity (FVC), episodes of FEV1 decline > 10%) and questionnaire outcomes (Leicester cough questionnaire (LCQ), Saint George Respiratory Questionnaire (SGRQ), and King's Sarcoidosis Questionnaire (KSQ)) using generalized linear mixed effect models. PM_2.5 level averaged over 14 days was associated with lower KSQ general health status (score change -6.60 per interquartile range (IQR) PM_2.5 increase). PM_2.5 level averaged over 10 and 14 days was associated with lower KSQ lung specific health status (score change -6.93 and -6.91, respectively). PM_2.5 levels were not associated with FEV₁, FVC, episodes of FEV₁ decline > 10%, or respiratory symptoms measured by SGRQ or LCQ. Ozone exposure was not associated with any health outcomes. In this small cohort of patients with fibrotic sarcoidosis, PM_2.5 exposure was associated with increased severity of respiratory and quality of life symptoms.

Radiographic Differentiation of Advanced Fibrocystic Lung Diseases

The concept of end-stage lung disease suggests a final common pathway for most diffuse parenchymal lung diseases. In accordance with this concept, end-stage disease is characterized radiographically and pathologically by the presence of extensive honeycombing. However, sequential computed tomographic (CT) scans obtained from patients with chronic diffuse lung disease evolve over time to show various advanced lung disease patterns other than honeycombing. In addition, several radiographically distinct honeycomb patterns, including microcystic, macrocystic, mixed, and combined emphysema and honeycombing, differentiate one advanced lung disease from another. For example, usual interstitial pneumonia (IP) usually shows mixed microcystic and macrocystic honeycombing. In contrast, CT images of long-standing fibrotic nonspecific IP typically show only small, scattered foci of honeycombing; instead, most enlarged airspaces observed in the advanced stage of this disease represent dilatation of bronchioles. In desquamative IP and pulmonary Langerhans cell histiocytosis, focal opacities typically evolve into emphysema-like lesions seen on CT imaging. In combined pulmonary fibrosis and emphysema and sarcoidosis, the cysts tend to be larger than those observed in usual IP. Sequential CT scans in other chronic, diffuse lung diseases also show various distinctive changes. This article highlights radiographic patterns of lung destruction that belie a single common pathway to end-stage lung disease. Recognition of distinct radiographic patterns of lung destruction can help differentiate diffuse parenchymal lung diseases, even in advanced stages of disease evolution.

Strategies for identifying pulmonary sarcoidosis patients at risk for severe or chronic disease

INTRODUCTION

Most of the morbidity and mortality resulting from pulmonary sarcoidosis relates to complications of fibrotic disease. Because the fibrosis related to pulmonary sarcoidosis is often of minimal clinical importance, pharmacotherapy is not mandated. However, a small fraction of pulmonary sarcoidosis patients develop significant lung fibrosis, and they could potentially benefit from anti-sarcoidosis therapy. A reliable algorithm to determine the likelihood of a pulmonary sarcoidosis patient developing fibrosis would minimize the toxicity of therapy and potentially prevent serious complications of the disease. Areas covered: The mechanisms of fibrosis in pulmonary sarcoidosis are discussed. Granulomatous inflammation is the major cause of fibrosis in pulmonary sarcoidosis. Known risk factors for the development of persistent and fibrotic sarcoidosis, including genetic risk factors are explored. Expert opinion/commentary: Currently, methods to determine the propensity of a pulmonary sarcoidosis to develop significant fibrosis are unreliable. This is an important unmet medical need.

Diagnostic Approach to Advanced Fibrotic Interstitial Lung Disease: Bringing Together Clinical, Radiologic, and Histologic Clues

Context.—

Idiopathic pulmonary fibrosis (IPF) is a distinctive clinicopathologic entity and the most common form of progressive diffuse lung scarring in older adults. Idiopathic pulmonary fibrosis manifests histopathologically as the usual interstitial pneumonia pattern. The usual interstitial pneumonia pattern is distinguished by geographically and temporally heterogeneous fibrosis that is peripherally accentuated, often with honeycombing and traction bronchiectasis. Idiopathic pulmonary fibrosis is not the only disease that leads to end-stage lung fibrosis, however, and several other entities may also cause advanced fibrosis. Surgical lung biopsies often present a diagnostic dilemma when they show clear evidence of advanced fibrosis, but the clinical, imaging, and/or histopathologic subcharacteristics suggest something other than IPF.

Objective.—

To address this dilemma, we review several other fibrotic lung diseases, including connective tissue disease–associated interstitial lung disease, chronic hypersensitivity pneumonitis, advanced pulmonary Langerhans cell histiocytosis, end-stage pulmonary sarcoidosis, Erdheim-Chester disease, Hermansky-Pudlak syndrome, and others, detailing their clinical, radiologic, and histopathologic attributes and emphasizing similarities to and differences from IPF.

Data Sources.—

Data sources comprised published peer-reviewed literature and personal experience of the authors.

Conclusions.—

Often, clues in the lung biopsy may offer the first suggestion of a fibrotic lung disease other than IPF, and accurate classification is important for prognosis, treatment, and the development of future therapies.

Worsening of pulmonary sarcoidosis

PURPOSE OF REVIEW

Despite the frequent occurrence of worsening pulmonary symptoms in pulmonary sarcoidosis patients, there is little available information concerning this topic.

RECENT FINDINGS

In this review, we outline the various causes for these symptoms. We propose to partition the various causes for these symptoms into specific categories.

SUMMARY

We believe that these categories will provide the clinician a framework to evaluate pulmonary sarcoidosis patients with such symptoms in a rigorous way that may be useful in optimizing their care.

Advanced pulmonary sarcoidosis

PURPOSE OF REVIEW

To present an update on the most recent contributions in advanced pulmonary sarcoidosis (APS).

RECENT FINDINGS

Pathology is better described and the differences between fibrosing pulmonary sarcoidosis and usual interstitial pneumonia (UIP) are clarified. Serial spirometry is the most reliable tool for monitoring evolution. Survival may be predicted by an integrative algorithm based on pulmonary function and computed tomography (CT).

SUMMARY

APS is characterized by significant fibrocystic pulmonary lesions at CT and pathology. There are two main patterns of APS, one with predominant central bronchovascular distortion, often associated with airflow limitation, and the other with predominant honeycombing with a different location than in UIP with severe restrictive impairment and very low diffusion capacity of the lung for carbon monoxide. APS may be burnt out but is most often still active as evidenced by several findings, including on F-fluorodeoxyglucose-PET. There is an increased mortality and morbidity with chronic respiratory insufficiency, pulmonary hypertension stemming from multiple mechanisms, chronic pulmonary aspergillosis and extra infections. Acute worsening episodes are frequent. Serial spirometry, particularly forced vital capacity, is the most reliable tool for monitoring evolution. A new elegant algorithm based on pulmonary function and CT may predict survival. Despite important stakes, there is still a lack of therapeutic recommendations. However, the use of antisarcoidosis treatment is most often required at least as a temporary trial. Finally, the effect of pulmonary hypertension treatment has recently been the object of further evaluation.

Severe Sarcoidosis

In sarcoidosis, reduction in mortality and the prevention of disability due to major organ involvement are treatment goals. Thus, it is important to recognize severe disease and identify patients at higher risk of progression to severe disease. In this article, fibrotic lung disease and cardiac sarcoidosis are reviewed as the major contributors to sarcoidosis mortality and morbidity. In the absence of a standardized definition of severe pulmonary disease, a multidisciplinary approach to clinical staging is suggested, based on symptoms, pulmonary function tests, and imaging findings at presentation, integrated with the duration of disease and longitudinal disease behavior during early follow-up.

Chest Computed Tomography-Based Scoring of Thoracic Sarcoidosis: Inter-rater Reliability of CT Abnormalities

PURPOSE

To determine inter-rater reliability of sarcoidosis-related computed tomography (CT) findings that can be used for scoring of thoracic sarcoidosis.

MATERIALS AND METHODS

CT images of 51 patients with sarcoidosis were scored by five chest radiologists for various abnormal CT findings (22 in total) encountered in thoracic sarcoidosis. Using intra-class correlation coefficient (ICC) analysis, inter-rater reliability was analysed and reported according to the Guidelines for Reporting Reliability and Agreement Studies (GRRAS) criteria. A pre-specified sub-analysis was performed to investigate the effect of training. Scoring was trained in a distinct set of 15 scans in which all abnormal CT findings were represented.

RESULTS

Median age of the 51 patients (36 men, 70%) was 43 years (range 26 - 64 years). All radiographic stages were present in this group. ICC ranged from 0.91 for honeycombing to 0.11 for nodular margin (sharp versus ill-defined). The ICC was above 0.60 in 13 of the 22 abnormal findings. Sub-analysis for the best-trained observers demonstrated an ICC improvement for all abnormal findings and values above 0.60 for 16 of the 22 abnormalities.

CONCLUSIONS

In our cohort, reliability between raters was acceptable for 16 thoracic sarcoidosis-related abnormal CT findings.

KEY POINTS

• Thoracic sarcoidosis is common; knowledge on reliability of CT scoring is limited. • Scoring CT abnormalities in pulmonary sarcoidosis can achieve good inter-rater agreement. • CT scoring validation in thoracic sarcoidosis is important for diagnostic and prognostic studies.

Pulmonary fibrosis in sarcoidosis. Clinical features and outcomes

Sarcoidosis is a systemic inflammatory disease with a predilection for the respiratory system. Although most patients enter remission and have good long-term outcomes, up to 20% develop fibrotic lung disease, whereby granulomatous inflammation evolves to pulmonary fibrosis. There are several radiographic patterns of pulmonary fibrosis in sarcoidosis; bronchial distortion is common, and other patterns, including honeycombing, are variably observed. The development of pulmonary fibrosis is associated with significant morbidity and can be fatal. Dyspnea, cough, and hypoxemia are frequent clinical manifestations. Pulmonary function testing often demonstrates restriction from parenchymal involvement, although airflow obstruction from airway-centric fibrosis is also recognized. Complications of fibrotic pulmonary sarcoidosis include pulmonary hypertension from capillary obliteration and chronic aspergillus disease, with hemoptysis a common and potentially life-threatening manifestation. Immunosuppression is not always indicated in end-stage sarcoidosis. Lung transplantation should be considered for patients with severe fibrotic pulmonary sarcoidosis, as mortality is high in these patients.

Rare causes of pulmonary hypertension: spectrum of radiological findings and review of the literature

Following a brief introduction covering the clinical signs and symptoms of pulmonary hypertension (PH), its most recent classification into six groups, and the computed tomography (CT) features common to all forms of PH, this paper illustrates the typical patterns that can be found on chest radiography and CT in rare causes of PH. We present and compare with the existing literature our personal series of cases of rare forms of PH, found in the following diseases: veno-occlusive disease, pulmonary capillary haemangiomatosis, non-thrombotic pulmonary embolism (tumour embolism and carcinomatous lymphangitis, talcosis, hydatid disease), pulmonary artery sarcoma, neurofibromatosis, sarcoidosis, and Langerhans cell histiocytosis. Rare forms of PH show low incidence and prevalence, and are, therefore, poorly recognised. Their diagnosis is a challenge for clinicians, pathologists, and radiologists, and any additional knowledge about the CT findings may help the diagnosis in the case of patients affected by PH of unknown origin.

Advances and perspectives in lung cancer imaging using multidetector row computed tomography

The introduction of multidetector row computed tomography (CT) into clinical practice has revolutionized many aspects of the clinical work-up. Lung cancer imaging has benefited from various breakthroughs in computing technology, with advances in the field of lung cancer detection, tissue characterization, lung cancer staging and response to therapy. Our paper discusses the problems of radiation, image visualization and CT examination comparison. It also reviews the most significant advances in lung cancer imaging and highlights the emerging clinical applications that use state of the art CT technology in the field of lung cancer diagnosis and follow-up.

The clinical and immunologic features of pulmonary fibrosis in sarcoidosis

Sarcoidosis is a multisystem, granulomatous disease that most often affects the lungs. The clinical course is highly variable; many patients undergo spontaneous remission, but up to a third of patients progresses to a chronic disease course. The development of pulmonary fibrosis (PF) in a subset of patients with chronic disease has a negative impact on morbidity and mortality. While sarcoidosis-associated PF can be progressive, it is often referred to as "burnt out" disease, a designation reflecting inactive granulomatous inflammation. The immune mechanisms of sarcoidosis-associated PF are not well understood. It is not clear if fibrotic processes are active from the onset of sarcoidosis in predisposed individuals, or whether a profibrotic state develops as a response to ongoing inflammation. Transforming growth factor β (TGF-β) is an important profibrotic cytokine, and in sarcoidosis, distinct genotypes of TGF-β have been identified in those with PF. The overall cytokine profile in sarcoidosis-associated PF has not been well characterized, although a transition from a T helper 1 to a T helper 2 signature has been proposed. Macrophages have important regulatory interactions with fibroblasts, and the role of alveolar macrophages in sarcoidosis-associated PF is a compelling target for further study. Elucidating the natural history of sarcoidosis-associated PF will inform our understanding of the fundamental derangements, and will enhance prognostication and the development of therapeutic strategies.

[Thoracic sarcoidosis]

Sarcoidosis is a multisystemic granulomatous disease of unknown etiology. It mainly affects the thoracic lymph nodes and the lungs. The staging of sarcoidosis, which classifies patients according to their probability of spontaneous remission, is based on the plain chest film findings. Plain chest films are not as sensitive as high resolution computed tomography (HRCT) at detecting involvement of the lymph nodes, lungs, or bronchi. The high resolution CT findings can be typical, practically pathognomic, or atypical. High resolution CT provides information about the activity of the disease and detects incipient signs of fibrosis and other complications. To reach the diagnosis, it is necessary to correlate the clinical and radiological findings (and often the histological findings). Cardiac involvement can cause sudden death. The diagnosis of cardiac involvement is difficult; it is based on various imaging tests, like magnetic resonance imaging, which is more specific, and positron emission tomography. Diagnostic confirmation by endomyocardial biopsy is obtained in few patients.

[Pulmonary sarcoidosis imaging]

Sarcoidosis is a juvenile systemic granulomatosis. Its polymorphic clinical presentation depends on its different localisations, thoracic and extrathoracic. The role of imaging is very important for all localisations; but for mediastinopulmonary involvement, which is the most frequent (>90% of cases), it plays a major role in detecting the disease, diagnosing it, its prognosis, decision-making regarding treatment of it and in the monitoring of its development. Standard radiography, which sometimes detects the disease, forms the basis for its four-stage prognostic classification. CT scanning enables the study of mediastinal and hilar lymphadenopathy and the study of parenchyma, making it possible to identify micronodules of lymphatic distributions, alveolar opacities, septal lines, ground-glass hyperintensities, nodules surrounded by a ring of satellite micronodules, peribronchovascular thickening; all potentially reversible lesions. Elsewhere, it highlights irreversible fibrous lesions: hilar peripheral linear opacities; septal linear opacities; bronchial distortion, honeycomb destruction or even perihilar fibrotic masses. Less frequently we can visualise bronchiolar or cystic involvement. Benign in most cases, the sarcoidosis prognosis becomes bleaker in the event of hemoptysis, Aspergillus colonisation or before the onset of pulmonary hypertension.

Lung cancer: Morphological and functional approach to screening, staging and treatment planning

Lung cancer is a major problem in public health and constitutes the leading cause of cancer-related mortality in the world. Lung cancer screening with low-dose computed tomography is promising but needs to overcome many difficulties, such as the large number of incidentally discovered nodules, the radiation dose delivered to the patient during a whole screening program and its cost. The ultimate target point represented by the reduction of lung cancer-related mortality needs to be proved in large, well-designed, randomized, multicenter, prospective trials. Lung cancer staging by morphological tools seems to be limited owing to the presence of metastases in normal-sized lymph nodes. In this context, multidetector computed tomography cannot be used alone but is useful in conjunction with molecular imaging and MRI. Today, flurodeoxglucose PET-CT appears to be the most accurate method for lung cancer staging and may prevent unnecessary thoracotomies. For treatment planning, flurodeoxglucose PET-CT is playing an increasing role in radiotherapy planning at the target selection and definition steps.

Sarcoidosis

Sarcoidosis is a multisystemic disorder of unknown cause characterized by the formation of immune granulomas in involved organs. It is an ubiquitous disease with incidence (varying according to age, sex, race and geographic origin) estimated at around 16.5/100,000 in men and 19/100,000 in women. The lung and the lymphatic system are predominantly affected but virtually every organ may be involved. Other severe manifestations result from cardiac, neurological, ocular, kidney or laryngeal localizations. In most cases, sarcoidosis is revealed by persistent dry cough, eye or skin manifestations, peripheral lymph nodes, fatigue, weight loss, fever or night sweats, and erythema nodosum. Abnormal metabolism of vitamin D3 within granulomatous lesions and hypercalcemia are possible. Chest radiography is abnormal in about 90% of cases and shows lymphadenopathy and/or pulmonary infiltrates (without or with fibrosis), defining sarcoidosis stages from I to IV. The etiology remains unknown but the prevailing hypothesis is that various unidentified, likely poorly degradable antigens of either infectious or environmental origin could trigger an exaggerated immune reaction in genetically susceptible hosts. Diagnosis relies on compatible clinical and radiographic manifestations, evidence of non-caseating granulomas obtained by biopsy through tracheobronchial endoscopy or at other sites, and exclusion of all other granulomatous diseases. The evolution and severity of sarcoidosis are highly variable. Mortality is estimated at between 0.5–5%. In most benign cases (spontaneous resolution within 24–36 months), no treatment is required but a regular follow-up until recovery is necessary. In more serious cases, a medical treatment has to be prescribed either initially or at some point during follow-up according to clinical manifestations and their evolution. Systemic corticosteroids are the mainstay of treatment of sarcoidosis. The minimal duration of treatment is 12 months. Some patients experience repeated relapses and may require long-term low-dose corticosteroid therapy during years. Other treatments (immunosuppressive drugs and aminoquinolins) may be useful in case of unsatisfactory response to corticosteroids, poor tolerance and as sparing agents when high doses of corticosteroids are needed for a long time. In some strictly selected cases refractory to standard therapy, specific antiTNF-α agents may offer precious improvement. Some patients benefit from topical corticosteroids.

Pulmonary hypertension in patients with interstitial lung diseases

Pulmonary hypertension (PH) in patients with interstitial lung diseases (ILDs) is not well recognized and can occur in the absence of advanced pulmonary dysfunction or hypoxemia. To address this topic, we identified relevant studies in the English language by searching the MEDLINE database (1966 to November 2006) and by individually reviewing the references of identified articles. Connective tissue disease-related ILD, sarcoidosis, idiopathic pulmonary fibrosis, and pulmonary Langerhans cell histiocytosis are the ILDs most commonly associated with PH. Pulmonary hypertension is an underrecognized complication in patients with ILDs and can adversely affect symptoms, functional capacity, and survival. Pulmonary hypertension can arise in patients with ILDs through various mechanisms, Including pulmonary vasoconstriction and vascular remodeling, vascular destruction associated with progressive parenchymal fibrosis, vascular inflammation, perivascular fibrosis, and thrombotic angiopathy. Diagnosis of PH in these patients requires a high index of suspicion because the clinical presentation tends to be nonspecific, particularly in the presence of an underlying parenchymal lung disease. Doppler echocardiography is an essential tool in the evaluation of suspected PH and allows ready recognition of cardiac causes. Right heart catheterization is needed to confirm the presence of PH, assess its severity, and guide therapy. Management of PH in patients with ILDs is guided by identification of the underlying mechanism and the clinical context. An increasing number of available pharmacologic agents in the treatment of PH allow possible treatment of PH in some patients with ILDs. Whether specific treatment of PH in these patients favorably alters functional capacity or outcome needs to be determined.