Associations between sarcoidosis, autoimmune diseases, and autoantibodies: a single-center retrospective study in China

Infectious and non-infectious precipitants of sarcoidosis

Sarcoidosis is a chronic inflammatory disease that can affect any organ in the body. Its exact cause remains unknown, but it is believed to result from a combination of genetic and environmental factors. Some potential causes of sarcoidosis include genetics, environmental triggers, immune system dysfunction, the gut microbiome, sex, and race/ethnicity. Genetic mutations are associated with protection against disease progression or an increased susceptibility to more severe disease, while exposure to certain chemicals, bacteria, viruses, or allergens can trigger the formation of immune cell congregations (granulomas) in different organs. Dysfunction of the immune system, including autoimmune reactions, may also contribute. The gut microbiome and factors such as being female or having African American, Scandinavian, Irish, or Puerto Rican heritage are additional contributors to disease outcome. Recent research has suggested that certain drugs, such as anti-Programmed Death-1 (PD-1) and antibiotics such as tuberculosis (TB) drugs, may raise the risk of developing sarcoidosis. Hormone levels, particularly higher levels of estrogen and progesterone in women, have also been linked to an increased likelihood of sarcoidosis. The diagnosis of sarcoidosis involves a comprehensive assessment that includes medical history, physical examination, laboratory tests, and imaging studies. While there is no cure for sarcoidosis, the symptoms can often be effectively managed through various treatment options. Treatment may involve the use of medications, surgical interventions, or lifestyle changes. These disparate factors suggests that sarcoidosis has multiple positive and negative exacerbants on disease severity, some of which can be ameliorated and others which cannot.

Uncommon diagnosis of multinodular goiter - isolated extrapulmonary manifestation of sarcoidosis in thyroid gland (scientific case reports)

AIM

By means of the scientific description of two uncommon cases who underwent. surgical resection of multinodous goiter and following histopathological investigation revealing isolated extrapulmonary manifestation of sarcoidosis, this uncommon diagnosis including symptomatology, clinical findings, diagnostic and therapeutic management is to be illustrated.

CASE DESCRIPTIONS

Diagnostics: Scintigraphy of the thyroid gland with a left-thyroid cold node; ultrasound-guided puncture (cytological investigation, non-suspicious).

THERAPY

Elective thyroidectomy with no macroscopic anomalies und no abnormal aspects with regard to surgical tactic and technique. Histopathological investigation: Complete resection specimen of the thyroid gland with granulomatous inflammation consistent with sarcoidosis.

CLINICAL COURSE

Uneventful with no further manifestations of sarcoidosis in the following diagnostics.

DIAGNOSTICS

Ultrasound, inhomogeneous node (37×30×35 mm) of the right thyroideal gland with echo-poor parts and peripheral vascularization; scintigraphy showing marginally compensated unifocal autonomy of the thyroid gland (laboratory parameters, increased serum level of thyroglobulin [632 ng/mL]).

THERAPY

Planned right hemithyroidectomy with confirmed nodous structure of thyroid parenchyma, without suspicious lymph nodes. Histopathological investigation: 33-mm follicular, nodular, encapsulated structure of thyroid parenchyma (diagnosed as follicular adenoma); 2nd opinion: low-grade differentiated carcinoma of thyroid gland with angioinfiltrating growth and granulomatous inflammation of sarcoidosis type. Procedural intent: After tumor-board consultation, completing thyroidectomy was performed within a 5-weeks interval (pT2 pN0[0/1] V1 L0 G3 R0) with subsequent ablating radio'active iodine therapy; 18 F-FDG-PET-CT (several atypical infiltrates within the right upper lobe of the lung) and bronchoscopy with no detection of further manifestation of sarcoidosis.

CONCLUSION

Sarcoidosis is considered a rare granulomatous multi-locular, systemic disease of not completely known etiopathogenesis with substantial heterogeneity. In most cases, it is associated with the lung, but which can become manifest in various organs. Frequently, extrapulmonary manifestations are usually detected as histological findings by coincidence, which require further investigation to find out additional manifestations as well as to exclude florid infection or other granulomatous processes (clarifying competently differential diagnosis). Therapy is only indicated in symptomatic organ manifestations, taking into account the high rate of spontaneous healing and possible side effects.

Advance in pathogenesis of sarcoidosis: Triggers and progression

Sarcoidosis, a multisystemic immune disease, significantly impacts patients' quality of life. The complexity and diversity of its pathogenesis, coupled with limited comprehensive research, had hampered both diagnosis and treatment, resulting in an unsatisfactory prognosis for many patients. In recent years, the research had made surprising progress in the triggers of sarcoidosis (genetic inheritance, infection and environmental factors) and the abnormal regulations on immunity during the formation of granuloma. This review consolidated the latest findings on sarcoidosis research, providing a systematic exploration of advanced studies on triggers, immune-related regulatory mechanisms, and clinical applications. By synthesizing previous discoveries, we aimed to offer valuable insights for future research directions and the development of clinical diagnosis and treatment strategies.

Sarcoidosis-related autoimmune inflammation in COVID-19 convalescent patients

Currently, there are a large number of reports about the development of autoimmune conditions after COVID-19. Also, there have been cases of sarcoid-like granulomas in convalescents as a part of the post-COVID-19 syndrome. Since one of the etiological theories of sarcoidosis considers it to be an autoimmune disease, we decided to study changes in the adaptive humoral immune response in sarcoidosis and SARS-CoV-2 infection and to find out whether COVID-19 can provoke the development of sarcoidosis. This review discusses histological changes in lymphoid organs in sarcoidosis and COVID-19, changes in B cell subpopulations, T-follicular helper cells (Tfh), and T-follicular regulatory cells (Tfr), and analyzes various autoantibodies detected in these pathologies. Based on the data studied, we concluded that SARS-CoV-2 infection may cause the development of autoimmune pathologies, in particular contributing to the onset of sarcoidosis in convalescents.

Sarcoidosis and its relation to other immune-mediated diseases: Epidemiological insights

Several epidemiological studies show a co-occurrence of sarcoidosis with other immune-mediated diseases (IMD). There are many similarities between sarcoidosis and IMDs in their geographical distribution and risk factors. Understanding these similarities and identifying the differences can help us to better understand sarcoidosis and put it into context with other IMDs. In this review, we present the current knowledge about the overlap between sarcoidosis and other IMDs derived from epidemiological studies. Epidemiologic methods utilize study design and statistical analysis to describe the patterns in data and, ideally, identify causal relationships between an exposure and a health outcome. We discuss how study design and analysis may affect the interpretation of epidemiological studies on this topic and highlight some theories that attempt to explain the relation between sarcoidosis and other IMDs.

Granulomatous myopathy co-existent immune-mediated necrotizing myopathy: A case report

Granulomatous myopathy (GM) is a rare disease characterized by non-caseating inflammation of the skeletal muscle, with sarcoidosis as a common cause. Here, we report a case of GM co-existent immune-mediated necrotizing myopathy (IMNM) in which an anti-signal recognition particle (SRP) antibody was positive and a muscle biopsy showed a non-caseating granulomatous structure, along with myofiber necrosis and inflammatory cell infiltration.

Sarcoidosis and Autoimmune Inflammatory Syndrome Induced by Adjuvants

Currently, sarcoidosis remains one of the diseases with unknown etiology, which significantly complicates its diagnosis and treatment. Various causes of sarcoidosis have been studied for many years. Both organic and inorganic trigger factors, provoking the development of granulomatous inflammation are considered. However, the most promising and evidence-based hypothesis is the development of sarcoidosis as an autoimmune disease, provoked by various adjuvants in genetic predisposed individuals. This concept fits into the structure of the autoimmune/inflammatory syndrome, induced by adjuvants (ASIA) that was proposed in 2011 by Professor Shoenfeld Y. In this paper, the authors reveal the presence of major and minor ASIA criteria for sarcoidosis, propose a new concept of the course of sarcoidosis within the framework of ASIA, and point out the difficulties in creating a model of the disease and the selection of therapy. It is obvious that the data obtained not only bring us closer to understanding the nature of sarcoidosis, but also potentiate new studies confirming this hypothesis by obtaining a model of the disease.

Case report: Thyroid sarcoidosis as a rare localization of the disease: Report of two cases and review of the literature

Sarcoidosis is a multi-systemic disease of unknown etiology that is characterized by the formation of non-necrotizing and non-caseating granulomas in affected organs. Sarcoidosis granulomas can form in any organ, but the lungs and intrathoracic lymph nodes are the most commonly affected. Thyroid involvement in sarcoidosis is very rare, with prevalence estimates of 1–4.5% in case series of autopsied patients with systemic sarcoidosis. It is extremely rare for sarcoidosis to occur solely in the thyroid gland, but it is usually associated with the involvement of other organs, primarily the lungs and lymph nodes. Typical manifestations are diffuse goiter and solitary or multiple thyroid nodules. Thyroid function remains intact in the majority of cases, but sometimes it can result in hypothyroidism or hyperthyroidism. The diagnosis can be made after fine needle aspiration cytology, but usually it is diagnosed as an incidental finding while analyzing thyroidectomy tissue or during autopsy. Oral steroids are the cornerstone of thyroid sarcoidosis management, along with specific endocrinological treatment on some occasions. Given that we found only 71 reports of thyroid sarcoidosis available in the literature, we created and analyzed a cohort of 24 patients with thyroid sarcoidosis who were described in the literature in the 21st century and reported two additional cases of thyroid sarcoidosis.

Sarcoidosis and autoimmunity: In the depth of a complex relationship

Sarcoidosis is a chronic granulomatous disease that can virtually affect any organ. Its etiology is unknown, although it has been proposed that environmental or biological agents can act as triggers, ultimately leading to chronic inflammation in genetically predisposed individuals. The main component of sarcoid inflammation is represented by an exaggerated T- lymphocytic cellular response to a putative antigen that could not be efficiently cleared in the patient. However, several clinical and immunological observations, such as the association of sarcoidosis to autoimmune diseases or the presence of autoantibodies in the serum of patients with sarcoidosis, suggest that humoral-mediated immune response might also play a role in the pathogenesis of sarcoidosis. The aim of this review is to deepen the relationship between sarcoidosis and autoimmunity, by analyzing the most recent advances and proposing new fields of research.

Microvascular capillaroscopic abnormalities and occurrence of antinuclear autoantibodies in patients with sarcoidosis

We described nailfold videocapillaroscopy (NVC) findings and estimated the prevalence of serum anti-nuclear (ANA) and extractable nuclear antigen autoantibodies (ENA) in a cohort of sarcoidosis patients, comparing them with adequate healthy controls (HCs) and with primary Raynaud’s phenomenon patients (PRPs). NVC findings were also correlated with the occurrence of autoantibodies, current treatment, laboratory parameters, variables of lung function and whole-body imaging data. Twenty-six patients with sarcoidosis were assessed through NVC, laboratory parameters, pulmonary function tests, chest-X ray and 18- fluorodeoxyglucose positron emission tomography/computed tomography. The NVC parameters and ANA/ENA dosage were recorded also in 30 PRPs and 30 HCs. Sarcoidosis patients showed a higher rate of capillary dilations and nonspecific abnormalities and a lower mean capillary absolute number than PRPs and HCs (p < 0.01 for all comparisons). The prevalence of ANA positivity was higher in patients with sarcoidosis compared with PRPs and HCs (p < 0.02 for both), whereas ENA positivity was detected in one sarcoidosis patient (Ro52). Among sarcoidosis patients, the mean capillary absolute number negatively correlated with the C-reactive protein concentrations and was positively associated with the forced vital capacity percentage. Instead, a negative correlation was detected between serum ACE levels and the presence of capillary dilations (all p < 0.05). Our findings suggest a microvascular involvement in sarcoidosis whose investigation by NVC might be useful for the follow-up of patients displaying RP. Autoantibody positivity in sarcoidosis might suggest autoimmune implications in the disease or the production of autoantibodies reactive to tissue damage.

Autoimmunity in sarcoidosis: the tip of the Iceberg

Sarcoidosis is a mysterious condition with an etiology that has to date eluded explanation. Innumerable clinical and serological organ- and non-organ-specific autoimmune associations have been reported. Many of the associated conditions are life-threatening but easily manageable if diagnosed early. Due to the long latency that precedes the clinical onset of autoimmune diseases, it is prudent to ensure a long follow-up and a broad viewing perspective while maintaining a high index of suspicion when viewing the autoimmunity iceberg in sarcoidosis.