Management of Advanced Pulmonary Sarcoidosis

Advanced pulmonary sarcoidosis

Sarcoidosis affects the lungs in most patients. Manifestations of pulmonary sarcoidosis range from asymptomatic to death. Approximately a quarter of sarcoidosis patients develop chronic pulmonary disease. Advanced pulmonary sarcoidosis patients are those who have progressive disease and are at risk for significant morbidity and mortality. There are several features associated with advanced pulmonary disease: pulmonary fibrosis, pulmonary hypertension, chronic pulmonary inflammation, and/or complications of disease or therapy. Large retrospective studies have identified pulmonary fibrosis and pulmonary hypertension as the major causes of respiratory failure and death in pulmonary sarcoidosis. The high-resolution computer tomography scan (HRCT) and echocardiogram are key methods in screening for pulmonary hypertension and pulmonary fibrosis. Therapy for chronic pulmonary inflammation has been the major focus in chronic disease. However, treatment for pulmonary hypertension has been studied in sarcoidosis. To date, treatment studies for sarcoidosis associated progressive pulmonary fibrosis have been underpowered to demonstrate clear cut benefit of anti-fibrotic agents.

Lung transplantation in pulmonary sarcoidosis

Sarcoidosis is a systemic inflammatory disease of unknown etiology and variable clinical course. Pulmonary sarcoidosis is the most common presentation and accounts for most morbidity and mortality related to sarcoidosis. While sarcoidosis generally has good outcomes, few patients experience chronic disease. A minority of patients progress to a specific phenotype of sarcoidosis referred to advanced pulmonary sarcoidosis (APS) which includes advanced fibrosis, pulmonary hypertension and respiratory failure, leading to high morbidity and mortality. In patients with advanced disease despite medical therapy, lung transplantation may be the last viable option for improvement in quality of life. Though post-transplant survival is similar to that of other end-stage lung diseases, it is imperative that patients are evaluated and referred early to transplant centers with experience in APS. A multidisciplinary approach and clinical experience are crucial in detecting the optimal timing of referral, initiating comprehensive transplantation evaluation and listing, discussing surgical approach, and managing perioperative and post-transplant care. This review article seeks to address these aspects of lung transplantation in APS.

Bioinformatic meta-analysis reveals novel differentially expressed genes and pathways in sarcoidosis

Introduction

Sarcoidosis is a multi-system inflammatory disease of unknown origin with heterogeneous clinical manifestations varying from a single organ non-caseating granuloma site to chronic systemic inflammation and fibrosis. Gene expression studies have suggested several genes and pathways implicated in the pathogenesis of sarcoidosis, however, due to differences in study design and variable statistical approaches, results were frequently not reproducible or concordant. Therefore, meta-analysis of sarcoidosis gene-expression datasets is of great importance to robustly establish differentially expressed genes and signalling pathways.

Methods

We performed meta-analysis on 22 published gene-expression studies on sarcoidosis. Datasets were analysed systematically using same statistical cut-offs. Differentially expressed genes were identified by pooling of p-values using Edgington's method and analysed for pathways using Ingenuity Pathway Analysis software.

Results

A consistent and significant signature of novel and well-known genes was identified, those collectively implicated both type I and type II interferon mediated signalling pathways in sarcoidosis. In silico functional analysis showed consistent downregulation of eukaryotic initiation factor 2 signalling, whereas cytokines like interferons and transcription factor STAT1 were upregulated. Furthermore, we analysed affected tissues to detect differentially expressed genes likely to be involved in granuloma biology. This revealed that matrix metallopeptidase 12 was exclusively upregulated in affected tissues, suggesting a crucial role in disease pathogenesis.

Discussion

Our analysis provides a concise gene signature in sarcoidosis and expands our knowledge about the pathogenesis. Our results are of importance to improve current diagnostic approaches and monitoring strategies as well as in the development of targeted therapeutics.

Interstitial Lung Disease and Progressive Pulmonary Fibrosis: a World Trade Center Cohort 20-Year Longitudinal Study

PURPOSE

World Trade Center (WTC) exposure is associated with obstructive airway diseases and sarcoidosis. There is limited research regarding the incidence and progression of non-sarcoidosis interstitial lung diseases (ILD) after WTC-exposure. ILD encompasses parenchymal diseases which may lead to progressive pulmonary fibrosis (PPF). We used the Fire Department of the City of New York's (FDNY's) WTC Health Program cohort to estimate ILD incidence and progression.

METHODS

This longitudinal study included 14,525 responders without ILD prior to 9/11/2001. ILD incidence and prevalence were estimated and standardized to the US 2014 population. Poisson regression modeled risk factors, including WTC-exposure and forced vital capacity (FVC), associated with ILD. Follow-up time ended at the earliest of incident diagnosis, end of study period/case ascertainment, transplant or death.

RESULTS

ILD developed in 80/14,525 FDNY WTC responders. Age, smoking, and gastroesophageal reflux disease (GERD) prior to diagnosis were associated with incident ILD, though FVC was not. PPF developed in 40/80 ILD cases. Among the 80 cases, the average follow-up time after ILD diagnosis was 8.5 years with the majority of deaths occurring among those with PPF (PPF: n = 13; ILD without PPF: n = 6).

CONCLUSIONS

The prevalence of post-9/11 ILD was more than two-fold greater than the general population. An exposure-response gradient could not be demonstrated. Half the ILD cases developed PPF, higher than previously reported. Age, smoking, and GERD were risk factors for ILD and PPF, while lung function was not. This may indicate that lung function measured after respirable exposures would not identify those at risk for ILD or PPF.

Fibrotic Pulmonary Sarcoidosis

Fibrotic pulmonary sarcoidosis (fPS) affects about 20% of patients. fPS carries a significant morbidity and mortality. However, its prognosis is highly variable, depending mainly on fibrosis extent, functional impairment severity, and the development of pulmonary hypertension. Moreover, fPS outcomes are also influenced by several other complications, including acute exacerbations, and infections. fPS natural history is unknown, in particular regarding the risk of progressive self-sustaining fibrosis. The management of fPS is challenging, including anti-inflammatory treatment if granulomatous activity persists, rehabilitation, and in highly selected patients antifibrotic treatment and lung transplantation.

Monitoring of Sarcoidosis

This article focuses on the monitoring of pulmonary sarcoidosis. The monitoring of sarcoidosis is, in part, focused on serial change in major organ involvement but also includes diagnostic re-evaluation and review of change in quality of life. Recent criteria for progression of fibrotic interstitial lung disease are adapted to pulmonary sarcoidosis. The frequency and nature of monitoring are discussed, integrating baseline risk stratification and strategic treatment goals. Individual variables used to identify changes in pulmonary disease severity are discussed with a focus on their flaws and the need for a multidimensional approach. Other key monitoring issues are covered briefly.

Health-Related Quality of Life Assessment in Sarcoidosis

Health-related quality of life (HRQoL) is of major concern to patients with sarcoidosis. HRQoL impairment is the most common reason to treat the disease. Advances in patient-reported outcome (PRO) methodology offer the promise to use these instruments to follow quality of life in individual patients with sarcoidosis over time. Several HRQoL issues will be highlighted including their clinical importance, common causes in patients with sarcoidosis, the construction and use of PROs in clinical sarcoidosis trials, methods to adapt PROs to monitor HRQoL in individual patients with sarcoidosis, and the approach to improving HRQoL in this disease.

High-Risk Sarcoidosis: A Focus on Pulmonary, Cardiac, Hepatic and Renal Advanced Diseases, as Well as on Calcium Metabolism Abnormalities

Although sarcoidosis is generally regarded as a benign condition, approximately 20-30% of patients will develop a chronic and progressive disease. Advanced pulmonary fibrotic sarcoidosis and cardiac involvement are the main contributors to sarcoidosis morbidity and mortality, with failure of the liver and/or kidneys representing additional life-threatening situations. In this review, we discuss diagnosis and treatment of each of these complications and highlight how the integration of clinical, pathological and radiological features may help predict the development of such high-risk situations in sarcoid patients.

Clinical Manifestations and Management of Fibrotic Pulmonary Sarcoidosis

Fibrotic pulmonary sarcoidosis represents a distinct and relatively uncommon manifestation within the spectrum of sarcoidosis and has substantial morbidity and mortality. Due to the scarcity of research focused on this specific disease subtype, our current understanding of pathogenesis and optimal management remains constrained. This knowledge gap underscores the need for further investigation into areas such as targeted therapies, lung transplantation, and quality of life of patients with fibrotic pulmonary sarcoidosis. The primary aim of this review is to discuss recent developments within the realm of fibrotic pulmonary sarcoidosis to foster a more comprehensive understanding of the underlying mechanisms, prognosis, and potential treatment modalities.

Emerging Therapeutic Options for Refractory Pulmonary Sarcoidosis: The Evidence and Proposed Mechanisms of Action

Sarcoidosis is a systemic disease with heterogenous clinical phenotypes characterized by non-necrotizing granuloma formation in affected organs. Most disease either remits spontaneously or responds to corticosteroids and second-line disease-modifying therapies. These medications are associated with numerous toxicities that can significantly impact patient quality-of-life and often limit their long-term use. Additionally, a minority of patients experience chronic, progressive disease that proves refractory to standard treatments. To date, there are limited data to guide the selection of alternative third-line medications for these patients. This review will outline the pathobiological rationale behind current and emerging therapeutic agents for refractory or drug-intolerant sarcoidosis and summarize the existing clinical evidence in support of their use.

Pulmonary hemodynamics and transplant-free survival in sarcoidosis-associated pulmonary hypertension: Results from an international registry

Pulmonary hypertension (PH) is a risk factor for mortality in patients with sarcoidosis. Severe PH in chronic lung disease has previously been defined as mean pulmonary arterial pressure (mPAP) ≥ 35 mmHg or mPAP 25 ≥ mmHg with cardiac index (CI) ≤ 2 L/min/m2. However, there is no clear definition denoting severity of sarcoidosis-associated PH (SAPH). We aimed to determine pulmonary hemodynamic cut-off values where transplant-free survival was worse among patients with SAPH. This was a retrospective cohort analysis of the Registry of SAPH database focusing on pulmonary hemodynamic predictors of transplant-free survival among patients with precapillary SAPH. Cox regression was performed to determine which pulmonary hemodynamic values predicted death or lung transplantation. Kaplan-Meier survival analysis was performed on statistically significant predictors to determine pulmonary hemodynamic cut-off values where transplant-free survival was decreased. Decreased transplant-free survival occurred among SAPH patients with mPAP ≥ 40 mmHg and SAPH patients with pulmonary vascular resistance (PVR) ≥ 5 Woods units (WU). Transplant-free survival was not decreased in patients who fulfilled prior criteria of severe PH in chronic lung disease. We identified new cut-offs with decreased transplant-free survival in the SAPH population. Neither cut-off of mPAP ≥ 40 mmHg nor PVR ≥ 5 WU has previously been shown to be associated with decreased transplant-free survival in SAPH. These values could suggest a new definition of severe SAPH. Our PVR findings are in line with the most recent European Society of Cardiology/European Respiratory Society guideline definition of severe PH in chronic lung disease.

The Symptoms of Pulmonary Sarcoidosis

The aim of this manuscript is to provide a comprehensive review of the etiology, measurement, and treatment of common pulmonary symptoms associated with sarcoidosis. The assessment of symptoms associated with pulmonary sarcoidosis is an important component of disease management. Some symptoms of pulmonary sarcoidosis are sensitive but nonspecific markers of disease activity, and the absence of such symptoms provides evidence that the disease is quiescent. Although quantifiable objective measurements of pulmonary physiology and chest imaging are important in the assessment of pulmonary sarcoidosis, they correlate poorly with the patient's quality of life. Because the symptoms of pulmonary sarcoidosis directly relate to how the patient feels, they are reasonable endpoints in terms of clinical research and individual patient care. Recently, the symptoms of pulmonary sarcoidosis are capable of being quantified via patient-reported outcome measures and electronic devices. We conclude that a thorough assessment of the symptoms associated with pulmonary sarcoidosis improves patient care because it is a useful screen for manifestations of the disease, provides insight into the pathophysiology of manifestations of sarcoidosis, and may assist in optimizing treatment.

Molecular Mechanism in the Development of Pulmonary Fibrosis in Patients with Sarcoidosis

Sarcoidosis is a multisystemic disease of unknown etiology characterized by the formation of granulomas in various organs, especially lung and mediastinal hilar lymph nodes. The clinical course and manifestations are unpredictable: spontaneous remission can occur in approximately two thirds of patients; up to 20% of patients have chronic course of the lung disease (called advanced pulmonary sarcoidosis, APS) resulting in progressive loss of lung function, sometimes life-threatening that can lead to respiratory failure and death. The immunopathology mechanism leading from granuloma formation to the fibrosis in APS still remains elusive. Recent studies have provided new insights into the genetic factors and immune components involved in the clinical manifestation of the disease. In this review we aim to summarize the clinical-prognostic characteristics and molecular pathways which are believed to be associated with the development of APS.

From Karl Wurm and Guy Scadding's staging to 18F-FDG PET/CT scan phenotyping and far beyond: perspective in the evading history of phenotyping in sarcoidosis

Sarcoidosis is an inflammatory granulomatous disease of unknown etiology involving any organ or tissue along with any combination of active sites, even the most silent ones clinically. The unpredictable nature of the sites involved in sarcoidosis dictates the highly variable natural history of the disease and the necessity to cluster cases at diagnosis based on clinical and/or imaging common characteristics in an attempt to classify patients based on their more homogeneous phenotypes, possibly with similar clinical behavior, prognosis, outcome, and therefore with therapeutic requirements. In the course of the disease's history, this attempt relates to the availability of a means of detection of the sites involved, from the Karl Wurm and Guy Scadding's chest x-ray staging through the ACCESS, the WASOG Sarcoidosis Organ Assessment Instruments, and the GenPhenReSa study to the 18F-FDG PET/CT scan phenotyping and far beyond to new technologies and/or the current "omics." The hybrid molecular imaging of the 18F-FDG PET/CT scan, by unveiling the glucose metabolism of inflammatory cells, can identify high sensitivity inflammatory active granulomas, the hallmark of sarcoidosis-even in clinically and physiologically silent sites-and, as recently shown, is successful in identifying an unexpected ordered stratification into four phenotypes: (I) hilar-mediastinal nodal, (II) lungs and hilar-mediastinal nodal, (III) an extended nodal supraclavicular, thoracic, abdominal, inguinal, and (IV) all the above in addition to systemic organs and tissues, which is therefore the ideal phenotyping instrument. During the "omics era," studies could provide significant, distinct, and exclusive insights into sarcoidosis phenotypes linking clinical, laboratory, imaging, and histologic characteristics with molecular signatures. In this context, the personalization of treatment for sarcoidosis patients might have reached its goal.

Living with sarcoidosis: Virtual roundtable dialogue with patients and healthcare professionals

BACKGROUND

Sarcoidosis is a multisystem disease, characterised by the infiltration of various organs by non-necrotising granulomas. The disease's heterogeneity complicates the study of patients' experiences.

OBJECTIVE

To gather insight into life experiences, unmet needs and views on hypothetically emerging treatment options among patients living with sarcoidosis.

METHODS

Multinational, virtual, interactive, moderated discussion of specific questions between people with sarcoidosis, with experienced clinicians participating.

RESULTS

Nine patients with sarcoidosis from Australia, Denmark, Germany, Italy, Japan and the US, and three clinicians took part. All patients had pulmonary sarcoidosis, self-assessed as mild by five patients. The path to diagnosis was convoluted, with up to four physicians and a large number of tests involved. There was agreement that the process would be improved by earlier referral to specialists. The patients made a clear distinction between 'living with a condition' (adapting to the disease) and 'being ill'. The concept of remission was viewed sceptically as disease might develop in multiple organs. Panellists had a pragmatic attitude to therapies: side effects during a treatment course were accepted if overall symptoms improved. When considering hypothetical new therapies, improved quality of life (QoL) was the most important need; improved tolerability had lower priority. New therapies should be targeted on reducing disease progression and improving symptoms and QoL rather than corticosteroid withdrawal.

CONCLUSIONS

The interactive exchange provided insights into the need for earlier specialist referrals, distrust of the concept of remission in sarcoidosis, and the need for therapies targeted on reducing disease progression and improving symptoms and QoL.

Pulmonary vasodilator therapy in sarcoidosis-associated pulmonary hypertension may decrease lung function decline and mortality

The efficacy of treating sarcoidosis-associated pulmonary hypertension (SAPH) with pulmonary vasodilator therapy is unclear. The INCREASE trial showed improvement in 6-minute walk distance (6MWD) and in decline in functional vital capacity (FVC) in patients with interstitial lung disease and pulmonary hypertension. We hypothesize that patients with SAPH treated with pulmonary vasodilators have reduced decline in FVC. We retrospectively analyzed patients with SAPH who underwent lung transplantation evaluation. The primary objective was to compare change in FVC between patients with SAPH who received pulmonary vasodilators (treated) and those who did not (untreated). Secondary objectives were to compare the change in 6MWD, change in oxygen requirement, transplant rates, and mortality between treated and untreated SAPH patients. We identified 58 patients with SAPH; 38 patients received pulmonary vasodilator therapy, and 20 patients did not. Treated SAPH patients had significantly less decline in FVC than untreated SAPH patients (+54 mL vs. -357 mL, p < 0.01). Treated SAPH patients had significantly higher survival than untreated SAPH patients. Receiving PH therapy was significantly associated with a change in FVC (estimate 0.36 ± 0.07, p < 0.01) and decreased mortality (hazard ratio 0.29, confidence interval 0.12-0.67, p < 0.01). Among patients with SAPH, those who received pulmonary vasodilator therapy had significantly less decline in FVC and increased survival. Receiving pulmonary vasodilator therapy was significantly associated with FVC change and decreased mortality. These study findings point towards potential benefit of pulmonary vasodilator therapy in SAPH patients. Further prospective studies are required to fully elucidate the benefits of pulmonary vasodilator therapy in SAPH.

The management of sarcoidosis in the 2020's by the primary care physician

Sarcoidosis is an idiopathic granulomatous disease that occurs worldwide and may affect any organ. Because the presenting symptoms of sarcoidosis are not specific for the disease, the primary care physician is usually the first provider to assess these patients. In addition, patients who have previously been diagnosed with sarcoidosis are usually followed longitudinally by primary care physicians. Therefore, these physicians are often the first to address sarcoidosis patient symptoms related to exacerbations of the disease, as well as first observe complications of sarcoidosis medications. This article outlines the approach to the evaluation, treatment and monitoring of sarcoidosis patients by the primary care physician.

Sarcoidosis

Sarcoidosis is a disease of unknown cause characterized by granulomatous inflammation. Although the lung is almost universally involved, any organ can be affected. Complex pathogenesis and protean clinical manifestations are additional features of the disease. The diagnosis is one of exclusion, although the presence of noncaseating granulomas at disease sites is a prerequisite in most cases. The management of sarcoidosis requires a multidisciplinary approach, particularly when the heart, the brain, or the eyes are involved. The paucity of effective therapies and the lack of reliable predictors of disease behavior greatly contribute to making sarcoidosis a challenging disease to manage.

An expert overview of pulmonary fibrosis in sarcoidosis

INTRODUCTION

Advanced pulmonary sarcoidosis refers to phenotypes of pulmonary sarcoidosis that often lead to significant loss of lung function, respiratory failure, or death. Around 20% of patients with sarcoidosis may progress to this state which is mainly driven by advanced pulmonary fibrosis. Advanced fibrosis often presents with associated complications of sarcoidosis including infections, bronchiectasis, and pulmonary hypertension.

AREAS COVERED

This article will focus on the pathogenesis, natural history of disease, diagnosis, and potential treatment options of pulmonary fibrosis in sarcoidosis. In the expert opinion section, we will discuss the prognosis and management of patients with significant disease.

EXPERT OPINION

While some patients with pulmonary sarcoidosis remain stable or improve with anti-inflammatory therapies, others develop pulmonary fibrosis and further complications. Although advanced pulmonary fibrosis is the leading cause of death in sarcoidosis, there are no evidence-based guidelines for the management of fibrotic sarcoidosis. Current recommendations are based on expert consensus and often include multidisciplinary discussions with experts in sarcoidosis, pulmonary hypertension, and lung transplantation to facilitate care for such complex patients. Current works evaluating treatments include the use of antifibrotic therapies for treatment in advanced pulmonary sarcoidosis.

Novel insights in fibrotic pulmonary sarcoidosis

PURPOSE OF REVIEW

In chronic pulmonary sarcoidosis, the transition from the inflammatory to the fibrotic stage of the lungs occurs in about 10-20% of cases, eventually causing end-stage fibrotic disease. To date, pathogenetic mechanisms and clinical management remain challenging; thus, we highlight the recent evidence in pulmonary fibrotic processes, clinical signs for an early detection and the potential role of the current investigated antifibrotic agents and promising targeted therapies.

RECENT FINDINGS

Recent findings of relevant key cellular pathways can be considered as a glimmer of light in the complexity of sarcoidosis. In some patients, granulomas persist and serve as a nidus for fibrosis growth, sustained by several fibrosis-stimulating cytokines. Preclinical studies have detected profibrotic, antifibrotic and pleiotropic T cells as promoters of fibrosis. Epigenetics, genetics and transcriptomics research can lead to new target therapies. Antifibrotic drug nintedanib has shown a positive effect on non-idiopathic pulmonary fibrosis fibrotic lung diseases including fibrotic sarcoidosis; other antifibrotic drugs are under investigation.

SUMMARY

Pulmonary fibrosis strongly impacts the outcome of sarcoidosis, and a better understanding of the underlying pathogenic mechanisms can facilitate the development of novel treatments, improving clinical care and life expectancy of these patients. The greatest challenge is to investigate effective antifibrotic therapies once fibrosis develops. The role of these findings in fibrotic sarcoidosis can be translated into other interstitial lung diseases characterized by the coexistence of inflammatory and fibrotic processes.