Sarcoidosis Diagnostic Score (SDS) system: Impact of race, sex, organ involvement and duration of symptoms prior to diagnosis.

BACKGROUND: The Sarcoidosis Diagnostic Score (SDS) system has been established for sarcoidosis patients based on the WASOG organ involvement criteria. We evaluated modifications of the SDS system to determine if they improved its the diagnostic accuracy. METHODS: Biopsy-confirmed patients with sarcoidosis seen during a 7-month period at 9 sarcoidosis centers across the world. Patients with non-sarcoidosis seen at the same sites were served as control patients. Comparing the SDS-biopsy and SDS-clinical values of five groups: duration of symptoms prior to evaluation (≤1 years vs.>1 years, ≤2 years vs.>2 years), organ involvement (lung, eye, or cardiac), race, and sex. RESULTS: A total of 990 patients with sarcoidosis and 1011 controls were included in this study. The SDS-clinical was significantly more discriminating for those undergoing assessment with symptoms for more than one year (z-statistic=2.570, p = 0.0102) or two years (z-statistic=2.546, p = 0.0109). However, the addition of two points for both >1 years and >2 years since onset of symptoms did not increase sensitivity and specificity of diagnosis with the SDS system. The SDS-clinical cut-off for patients with ocular or cardiac disease was two points higher than that for lung disease. There was no difference in SDS-clinical or biopsy AUC values based on gender or race. CONCLUSIONS: The longer the duration of symptoms prior to diagnosis, the more likely the diagnosis of sarcoidosis was correct. For patients presenting with ocular or cardiac symptoms, evidence of multi-organ involved can improve the diagnostic accuracy of the SDS-clinical.

Developmental drugs for sarcoidosis.

Sarcoidosis is a multi-organ granulomatous inflammatory disease of unknown etiology. Over 50% of patients will require treatment at some point in their disease and 10%-30% will develop a chronic progressive disease with pulmonary fibrosis leading to significant morbidity and mortality. Recently published guidelines recommend immunosuppressive therapy for sarcoidosis patients at risk of increased disease-related morbidity and mortality, and in whom disease has negatively impacted quality of life. Prednisone the currently recommended first line therapy is associated with significant toxicity however none of the other guideline recommended steroid sparing therapy is approved by regulatory agencies for use in sarcoidosis, and data in support of their use is weak. For patients with severe refractory disease requiring prolonged therapy, treatment options are limited. The need for expanding treatment options in sarcoidosis has been emphasized. Well conducted large, randomized trials evaluating currently available therapeutic options as well as novel pathways for targeting disease are necessary to better guide treatment decisions. These trials will not be without significant challenges. Sarcoidosis is a rare disease with heterogenous presentation and variable progression and clinical outcome. There are no universally agreed upon biomarkers of disease activity and measurement of outcomes is confounded by the need to balance patient centric measures and objective measures of disease activity. Our paper provides an update on developmental drugs in sarcoidosis and outlines several novel pathways that may be targeted for future drug development. Currently available trials are highlighted and ongoing challenges to drug development and clinical trial design are briefly discussed.

Hematologic and Oncologic Aspects of Sarcoidosis: Some of the Least Studied but Most Common Dilemmas.

The hematologic system is frequently involved in sarcoidosis. Lymphopenia is the most common hematologic manifestation noted, although anemia and thrombocytopenia also occur. The etiology of these common manifestations can be direct granulomatous infiltration of bone marrow, lymph nodes, or spleen or related to immunologic dysfunction. Although not life threatening, these problems can lead to cytopenias requiring close monitoring in patients receiving a variety of disease treatments. The relationship between sarcoidosis and malignancy remains complex. However, some sarcoidosis patients are at increased risk for the development of malignancies, particularly lymphomas and gastrointestinal cancers. Conversely, cancer patients can experience an increase in the likelihood for the development of breast cancer and lymphomas.

Hematological involvement in sarcoidosis: from cytopenias to lymphoma.

INTRODUCTION: We present an updated overview of the hematological involvementassociated with sarcoidosis, including a management approach forcytopenias and revisiting the association with hematologicalmalignancies. AREAS COVERED: Theetiology of cytopenias in sarcoidosis can be attributed to two majoretiopathogenic mechanisms: infiltration of hematopoietic organs suchas the spleen and bone marrow, and autoimmune-mediated cytopenias.With respect to the association with hematological malignancies, itrequires careful evaluation of patients from a chronologicalperspective. Patients must be classified into one of three pathogenicscenarios, including preexisting hematological malignancies,synchronous development of malignancy and sarcoidosis due to commonpredisposing factors, or sarcoidosis as a predisposing factor formalignancies. EXPERT OPINION: The association between sarcoidosis and hematologic involvement isbest understood as a pathogenic continuum, with cytopenias andhematologic neoplasms intertwined due to various etiopathogenicmechanisms. These mechanisms include sarcoid infiltration ofhematopoietic organs, common predisposing immunogenetics for thedevelopment of autoimmune cytopenias and malignancies, and anincreased risk of neoplasm development in patients with autoimmunecytopenias. Collaboration among the main specialties involved in theclinical management of these patients is crucial for an earlymonitoring and management.

High-Resolution CT Scan Fibrotic Patterns in Stage IV Pulmonary Sarcoidosis: Impact on Pulmonary Function and Survival.

BACKGROUND: Different patterns of fibrosis on high-resolution CT scans (HRCT) have been associated with reduced survival in some interstitial lung diseases. Nothing is known about HRCT scan patterns and survival in sarcoidosis. RESEARCH QUESTION: Will a detailed description of the extent and pattern of HRCT scan fibrosis in patients with stage IV pulmonary sarcoidosis impact pulmonary function and survival? STUDY DESIGN AND METHODS: Two hundred forty patients with stage IV sarcoidosis at two large tertiary institutions were studied. The earliest HRCT scan with fibrosis was reviewed for extent of fibrosis (< 10%, 10%-20%, and > 20%) and presence of bronchiectasis, upper lobe fibrocystic changes, basal subpleural honeycombing, ground-glass opacities (GGOs), large bullae, and mycetomas. Presence of sarcoidosis-associated pulmonary hypertension (SAPH) and pulmonary function testing performed within 1 year of HRCT were recorded. Patients were followed up until last clinic visit, death, or lung transplantation. RESULTS: The mean age was 58.4 years. Seventy-four percent were Black, 63% were female, and mean follow-up was 7.4 years. Death or LT occurred in 53 patients (22%). Thirty-one percent had > 20% fibrosis, 25% had 10%-20% fibrosis, and 44% had < 10% fibrosis. The most common HRCT abnormalities were bronchiectasis (76%), upper lobe fibrocystic changes (36%), and GGOs (28%). Twelve percent had basal subpleural honeycombing, and 32% had SAPH. Patients with > 20% fibrosis had more severe pulmonary impairment, were more likely to have SAPH (53%), and had worse survival (44% mortality; P < .001). Upper lobe fibrocystic changes, basal subpleural honeycombing, and large bullae were associated with worse pulmonary function and worse survival. Patients with basal subpleural honeycombing had the worst pulmonary function and survival (55% mortality; P < .001). GGOs were associated with worse pulmonary function but not worse survival, and mycetomas were associated with worse survival but not worse pulmonary function. A Cox proportional hazards model indicated that basal subpleural honeycombing (hazard ratio, 7.95), diffusion capacity for carbon monoxide < 40% (HR, 5.67) and White race (hazard ratio, 2.61) were independent predictors of reduced survival. INTERPRETATION: HRCT scan features of fibrotic pulmonary sarcoidosis had an impact on pulmonary function and survival. Presence of >20% fibrosis and basal subpleural honeycombing are predictive of worse pulmonary function and worse survival in patients with stage IV pulmonary sarcoidosis.

High-resolution CT phenotypes in pulmonary sarcoidosis: a multinational Delphi consensus study.

One view of sarcoidosis is that the term covers many different diseases. However, no classification framework exists for the future exploration of pathogenetic pathways, genetic or trigger predilections, patterns of lung function impairment, or treatment separations, or for the development of diagnostic algorithms or relevant outcome measures. We aimed to establish agreement on high-resolution CT (HRCT) phenotypic separations in sarcoidosis to anchor future CT research through a multinational two-round Delphi consensus process. Delphi participants included members of the Fleischner Society and the World Association of Sarcoidosis and other Granulomatous Disorders, as well as members' nominees. 146 individuals (98 chest physicians, 48 thoracic radiologists) from 28 countries took part, 144 of whom completed both Delphi rounds. After rating of 35 Delphi statements on a five-point Likert scale, consensus was achieved for 22 (63%) statements. There was 97% agreement on the existence of distinct HRCT phenotypes, with seven HRCT phenotypes that were categorised by participants as non-fibrotic or likely to be fibrotic. The international consensus reached in this Delphi exercise justifies the formulation of a CT classification as a basis for the possible definition of separate diseases. Further refinement of phenotypes with rapidly achievable CT studies is now needed to underpin the development of a formal classification of sarcoidosis.

D. Geraint James Lecture: The sarcoidosis saga: what insights from the past will guide us in the future.

The sarcoidosis community in general and the World Association of Sarcoidosis and Other Granulomatous diseases (WASOG) in particular have led efforts to improve sarcoidosis diagnosis and care. Evidence based guidelines regarding the diagnosis and treatment have recently been published. In addition, several clinical trials examining existing and new treatments for sarcoidosis have been completed and published. In addition, WASOG has developed criteria and identified Centers of Excellence for sarcoidosis care around the world. In discussing what insights from the past will guide us in the future, this paper focuses on three specific topics: updating the diagnosis of sarcoidosis, using placebo-controlled trials to illuminate the natural course of pulmonary sarcoidosis; and exploring multidisciplinary sarcoidosis clinic care using Centers of Excellence. New approaches for diagnosis of sarcoidosis and steroid tapering are proposed based on current literature.

Diagnosis of pulmonary sarcoidosis in tuberculosis endemic area-a narrative review.

Background and Objective: Pulmonary sarcoidosis and tuberculosis (TB) are the most frequent tissue-confirmed granulomatous diseases. Due to its unknown etiology, pulmonary sarcoidosis is diagnosed by ruling out other granulomatous diseases and necessitating clinical, radiological, and pathological evidence. There are many factors that contribute to the diagnostic dilemma between these two diseases. Even though some aspects of both diseases, such as their pathological evidence and abnormal X-ray findings, are quite similar, the treatment options for each are entirely different. The standard treatment for sarcoidosis is immunosuppressive agents such as glucocorticoids, which can exacerbate TB. Consequently, the overlap between clinical and radiological features constitutes a significant challenge for many physicians in selecting the optimal treatment for each patient. Therefore, the exclusion of pulmonary TB is a mandatory step for the diagnosis of pulmonary sarcoidosis. This article reviews and summarizes basic science and clinical research on distinguishing these two disorders. Methods: A systematic search of the MEDLINE and PubMed databases focusing on studies published within the last 35 years was conducted. The last search date is February 4, 2023. The authors used the following combinations of terms: tuberculosis, sarcoidosis, diagnosis, bronchoscopy, biomarkers, and radiography. All studies were reviewed, and 69 references from 1990 to 2023 were found to be relevant. Key Content and Findings: Innovative laboratory tests are essential for distinguishing between pulmonary sarcoidosis and TB. The Xpert MTB/RIF assay diagnoses TB with 98% sensitivity and 89% specificity. Loop-mediated isothermal amplification (LAMP) and simultaneous amplification and testing method for Mycobacterium tuberculosis rRNA (SAT-TB) are also highly sensitive and specific for TB diagnosis. Several novel tests, such as the difference of immune complexes for the ESAT-6/SFP-10 antigen in vitro with dynamic light scattering (DLS), lung tissue-based molecular markers, and the blood transcriptome, are promising for differentiating TB from sarcoidosis. Conclusions: Recent advancements in laboratory investigations, non-invasive procedures, and invasive procedures play an important role in the diagnosis of sarcoidosis in TB-endemic areas. However, further study is needed to evaluate the diagnostic performance of all tests in terms of their competency in distinguishing between TB and sarcoidosis.

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.

Efzofitimod: a novel anti-inflammatory agent for sarcoidosis.

Efzofitimod is a first-in-class biologic based on a naturally occurring splice variant of histidyl-tRNA synthetase (HARS) that downregulates immune responses via selective modulation of neuropilin-2 (NRP2). Preclinical data found high expression of NRP2 in sarcoidosis granulomas. Treatment with efzofitimod reduced the granulomatous inflammation induced by P. acnes in an animal model of sarcoidosis. A dose escalating trial of efzofitimod in sarcoidosis with chronic symptomatic pulmonary disease found that treatment with efzofitimod was associated with improved quality of life with a trend towards reduced glucocorticoid use and stable to improved pulmonary function. These studies have led to a large Phase 3 trial of efzofitimod in symptomatic pulmonary sarcoidosis.

Validation of the Sarcoidosis Diagnostic Score in a Multicontinental Study.

Rationale: The Sarcoidosis Diagnostic Score (SDS) has been established to quantitate the clinical features consistent with sarcoidosis in a monocentric study. Objectives: We aimed to confirm the diagnostic value of SDS in a large, multicontinental study and to assess the utility of SDS in differentiating sarcoidosis from alternative diagnoses, including infectious and noninfectious granulomatous diseases. Methods: We included patients with biopsy-confirmed sarcoidosis at nine centers across the world. Patients without sarcoidosis seen at the same sites served as control patients. Using a modified World Association of Sarcoidosis and Other Granulomatous Disorders organ assessment instrument, we scored all patients for the presence of granuloma on biopsy, highly probable symptoms, and least probable symptoms for each area. Two sarcoidosis scores were generated: SDS Biopsy (with biopsy) and SDS Clinical (without biopsy). SDS Clinical and Biopsy were calculated for all patients. We calculated and compared the area under the curve (AUC) for SDS Clinical and Biopsy according to different diagnosis scenarios. Results: A total of 1,041 patients with sarcoidosis and 1,035 without sarcoidosis were included. The results for SDS Clinical (AUC, 0.888; 95% confidence interval [CI], 0.874-0.902) and SDS Biopsy (AUC, 0.979; 95% CI, 0.973-0.985) according to AUC were good to excellent for differentiating sarcoidosis from alternative diagnosis. SDS Clinical was less discriminatory in males (P = 0.01) and in high tuberculosis prevalence centers (P < 0.001). However, SDS Clinical (AUC, 0.684; 95% CI, 0.602-0.766) and SDS Biopsy (AUC, 0.754; 95% CI, 0.673-0.835) were not sufficiently discriminative for noninfectious granulomatous diseases, but both SDSs could differentiate sarcoidosis from infectious granulomatous diseases. Algorithms were proposed for the SDS Clinical and SDS Biopsy to assist the clinician in the diagnostic process, and cutoff values were proposed for the SDS Clinical and SDS Biopsy, allowing the diagnosis of sarcoidosis to be safely confirmed or rejected in most cases except for noninfectious granulomatous disease. Conclusions: This multicontinental study confirms that both SDS Clinical and SDS Biopsy have good to excellent performance in discriminating sarcoidosis from alternative diagnoses. Differences in the AUC were seen for high tuberculosis prevalence versus low tuberculosis prevalence centers and for males versus females. Both SDSs had good discriminatory function for infectious granulomatous disease but failed in cases of noninfectious granulomatous disease such as berylliosis.

Sarcoidosis: Updates on therapeutic drug trials and novel treatment approaches.

Sarcoidosis is a systemic granulomatous inflammatory disease of unknown etiology. It affects the lungs in over 90% of patients yet extra-pulmonary and multi-organ involvement is common. Spontaneous remission of disease occurs commonly, nonetheless, over 50% of patients will require treatment and up to 30% of patients will develop a chronic progressive non-remitting disease with marked pulmonary fibrosis leading to significant morbidity and death. Guidelines outlining an immunosuppressive treatment approach to sarcoidosis were recently published, however, the strength of evidence behind many of the guideline recommended drugs is weak. None of the drugs currently used for the treatment of sarcoidosis have been rigorously studied and prescription of these drugs is often based on off-label" indications informed by experience with other diseases. Indeed, only two medications [prednisone and repository corticotropin (RCI) injection] currently used in the treatment of sarcoidosis are approved by the United States Food and Drug Administration. This situation results in significant reimbursement challenges especially for the more advanced (and often more effective) drugs that are favored for severe and refractory forms of disease causing an over-reliance on corticosteroids known to be associated with significant dose and duration dependent toxicities. This past decade has seen a renewed interest in developing new drugs and exploring novel therapeutic pathways for the treatment of sarcoidosis. Several of these trials are active randomized controlled trials (RCTs) designed to recruit relatively large numbers of patients with a goal to determine the safety, efficacy, and tolerability of these new molecules and therapeutic approaches. While it is an exciting time, it is also necessary to exercise caution. Resources including research dollars and most importantly, patient populations available for trials are limited and thus necessitate that several of the challenges facing drug trials and drug development in sarcoidosis are addressed. This will ensure that currently available resources are judiciously utilized. Our paper reviews the ongoing and anticipated drug trials in sarcoidosis and addresses the challenges facing these and future trials. We also review several recently completed trials and draw lessons that should be applied in future.

Controversies in the Treatment of Cardiac Sarcoidosis.

There are many challenging aspects of the management of cardiac sarcoidosis (CS) with corticosteroids and other immunosuppressive therapy (IST). First, it is not always clear who will benefit from therapy or when to initiate treatment. Secondly, there are no randomized controlled trials or large prospective studies to guide what medications to use, at what doses, and for how long. The European Respiratory Society (ERS) clinical practice guidelines on the treatment of sarcoidosis makes a strong recommendation for the use of immuno-suppressive therapy in CS patients with functional cardiac abnormalities, including heart blocks, dysrhythmias, or cardiomyopathy where patients are considered at-risk of adverse outcomes. Corticosteroids are the first line immunosuppressive therapy in CS however, early initiation of second-line steroid sparing medications has been advocated and there is data to suggest that concomitant initiation of therapy may be more beneficial. The use of anti-tumor necrosis factor (anti-TNF) agents (including infliximab and adalimumab) considered beneficial third-line anti-sarcoidosis treatment agents in other severe refractory manifestations of disease remains controversial.

WASOG statement on the diagnosis and management of sarcoidosis-associated pulmonary hypertension.

Sarcoidosis-associated pulmonary hypertension (SAPH) is an important complication of advanced sarcoidosis. Over the past few years, there have been several studies dealing with screening, diagnosis and treatment of SAPH. This includes the results of two large SAPH-specific registries. A task force was established by the World Association of Sarcoidosis and Other Granulomatous disease (WASOG) to summarise the current level of knowledge in the area and provide guidance for the management of patients. A group of sarcoidosis and pulmonary hypertension experts participated in this task force. The committee developed a consensus regarding initial screening including who should undergo more specific testing with echocardiogram. Based on the results, the committee agreed upon who should undergo right-heart catheterisation and how to interpret the results. The committee felt there was no specific phenotype of a SAPH patient in whom pulmonary hypertension-specific therapy could be definitively recommended. They recommended that treatment decisions be made jointly with a sarcoidosis and pulmonary hypertension expert. The committee recognised that there were significant defects in the current knowledge regarding SAPH, but felt the statement would be useful in directing future studies.

Management of Advanced Pulmonary Sarcoidosis.

The term "advanced sarcoidosis" is used for forms of sarcoidosis with a significant risk of loss of organ function or death. Advanced sarcoidosis often involves the lung and is described as "advanced pulmonary sarcoidosis" (APS), which includes advanced pulmonary fibrosis, associated complications such as bronchiectasis and infections, and pulmonary hypertension. Although APS affects a small proportion of patients with sarcoidosis, it is the leading cause of poor outcomes, including death. Here we review the major patterns of APS with a focus on the current management as well as potential approaches for improved outcomes for this most serious sarcoidosis phenotype.

Identifying a core outcome set for pulmonary sarcoidosis research - the Foundation for Sarcoidosis Research - Sarcoidosis Clinical OUtcomes Taskforce (SCOUT).

Background: Pulmonary sarcoidosis is a rare granulomatous disease of unknown aetiology. Heterogeneity in the outcomes measured in trials of treatment for pulmonary sarcoidosis has impacted on the ability to systematically compare findings, contributing to research inefficiency. The FSR-SCOUT study has aimed to address this heterogeneity by developing a core outcome set that represents a patient and health professional consensus on the most important outcomes to measure in future research for the treatment of pulmonary sarcoidosis. Research design and methods: systematic review of trial registries, narrative synthesis of published qualitative literature on the patient experience and results of a patient survey contributed to the development of a comprehensive list of outcomes that were rated in a two round online Delphi survey. The Delphi survey was completed by patients/carers and health professionals and the results discussed and ratified at an online consensus meeting. Results: 259 patients/carers and 51 health professionals completed both rounds of the Delphi survey. A pre-agreed definition of consensus was applied and the results discussed at an online consensus meeting attended by 17 patients and 7 health professionals). Fifteen outcomes, across five domains (physiological/clinical, treatment, resource use, quality of life, and death), reached the definition of consensus and were included in the core outcome set. Conclusions: The core outcome set represents a patient and health professional consensus on the most important outcomes for pulmonary sarcoidosis research. The use of the core outcome set in future trials, and efforts to validate its components, will enhance the relevance of trials to stakeholders and will increase the opportunity for the research to contribute to evidence synthesis.

Immune checkpoint inhibitor-associated sarcoidosis: A usually benign disease that does not require immunotherapy discontinuation.

OBJECTIVE: To analyse the clinical patterns of sarcoidosis triggered by immune checkpoint inhibitors (ICIs) in patients with cancer. PATIENTS AND METHODS: The ImmunoCancer International Registry is a big data-sharing multidisciplinary network from 18 countries dedicated to evaluating the clinical research of immune-related adverse events related to cancer immunotherapies. RESULTS: We identified 32 patients with biopsy-proven sarcoidosis. Underlying cancer included mainly melanoma (n = 24). Cancer immunotherapy consisted of monotherapy in 19 cases (anti-PD-1 in 18 and ipilimumab in 1) or combined ipilimumab + nivolumab in 13. The time median interval between initiation of ICI and sarcoidosis diagnosis was 3 months (range, 2-29 months). The use of combined ICI was associated with a shorter delay in developing sarcoidosis symptoms. The disease was symptomatic in 19 (59%) cases with mostly cutaneous, respiratory and general symptoms. The organs involved included mainly the mediastinal lymph nodes (n = 32), the lungs (n = 11), the skin (n = 10) and the eyes (n = 5). Pulmonary computed tomography studies showed bilateral hilar lymphadenopathy in all cases. There was no severe manifestation. Specific systemic therapy was required in only 12 patients (37%): oral glucocorticoids in 9, and hydroxychloroquine in 3. ICIs were held in 25 patients (78%) and definitively discontinued in 18 (56%) patients. Seven patients continued ICI treatment with a second flare in one case. In six additional patients, an ICI was reintroduced with no harm, and sarcoidosis relapsed in one of them. CONCLUSION: Our study shows that ICI-related sarcoidosis seems to have a specific profile, possibly more benign than that of idiopathic sarcoidosis, and does not necessarily imply ICI discontinuation.

COVID-19 and Sarcoidosis, Readiness for Vaccination: Challenges and Opportunities.

Sarcoidosis is an immune mediated chronic inflammatory disorder that is best characterized by non-caseating granulomas found in one or more affected organs. The COVID-19 pandemic poses a challenge for clinicians caring for sarcoidosis patients who may be at increased risk of infection compared to the general population. With the recent availability of COVID-19 vaccines, it is expected that clinicians raise questions regarding efficacy and safety in sarcoidosis. However, studies examining safety and efficacy of vaccines in sarcoidosis are lacking. In this review, we examine the current literature regarding vaccination in immunocompromised populations and apply them to sarcoidosis patients. The available literature suggests that vaccines are safe and effective in patients with autoimmune disorders and in those taking immunosuppressive medications. We strongly recommend the administration of COVID-19 vaccines in patients with sarcoidosis. We also present a clinical decision algorithm to provide guidance on vaccination of sarcoidosis patients against COVID-19.

Unsupervised Clustering Reveals Sarcoidosis Phenotypes Marked by a Reduction in Lymphocytes Relate to Increased Inflammatory Activity on 18FDG-PET/CT.

Introduction: Sarcoidosis is a T-helper cell mediated disease characterized by granulomatous inflammation. We posited that unsupervised clustering of various features in sarcoidosis would establish phenotypes associated with inflammatory activity measured by 18FDG-PET/CT. Our goal was to identify unique features capable of distinguishing clusters and subsequently examine the relationship with FDG avidity to substantiate their potential use as markers for sarcoidosis inflammation. Methods: We performed a retrospective study of a diverse, but primarily African American, cohort of 58 subjects with biopsy proven sarcoidosis followed at the University of Illinois Bernie Mac Sarcoidosis Center and Center for Lung Health who underwent 18FDG-PET/CT scan. Demographic, therapeutic, radiographic, and laboratory data were utilized in unsupervised cluster analysis to identify sarcoidosis phenotypes. The association between clusters, their defining features, and quantitative measurements on 18FDG-PET/CT was determined. The relevance of these features as markers of 18FDG-PET/CT inflammatory activity was also investigated. Results: Clustering determined three distinct phenotypes: (1) a predominantly African American cluster with chronic, quiescent disease, (2) a predominantly African American cluster with elevated conventional inflammatory markers, advanced pulmonary disease and extrathoracic involvement, and (3) a predominantly Caucasian cluster characterized by reduced lymphocyte counts and acute disease. In contrast to the chronic quiescent cluster, Clusters 2 and 3 were defined by significantly greater FDG avidity on 18FDG-PET/CT. Despite similarly increased inflammatory activity on 18FDG-PET/CT, Clusters 2, and 3 differed with regards to extrathoracic FDG avidity and circulating lymphocyte profiles, specifically CD4+ T-cells. Notably, absolute lymphocyte counts and CD4+ T-cell counts were found to predict 18FDG-PET/CT inflammatory activity by receiver operating curve analysis with a 69.2 and 73.42% area under the curve, respectively. Conclusions: Utilizing cluster analysis, three distinct phenotypes of sarcoidosis were identified with significant variation in race, disease chronicity, and serologic markers of inflammation. These phenotypes displayed varying levels of circulating inflammatory cells. Additionally, reduction in lymphocytes, specifically CD4+ T-cells, was significantly related to activity on 18FDG-PET/CT. Though future studies are warranted, these findings suggest that peripheral lymphocyte counts may be considered a determinant of sarcoidosis phenotypes and an indicator of active inflammation on 18FDG-PET/CT.