The causal relationship between sarcoidosis and autoimmune diseases: a bidirectional Mendelian randomization study in FinnGen.

Background: Sarcoidosis has been considered to be associated with many autoimmune diseases (ADs), but the cause-and-effect relationship between these two diseases has not been fully explored. Therefore, the objective of this study is to explore the possible genetic association between sarcoidosis and ADs. Methods: We conducted a bidirectional Mendelian randomization (MR) study using genetic variants associated with ADs and sarcoidosis (4,041 cases and 371,255 controls) from the FinnGen study. The ADs dataset comprised 96,150 cases and 281,127 controls, encompassing 44 distinct types of autoimmune-related diseases. Subsequently, we identified seven diseases within the ADs dataset with a case size exceeding 3,500 and performed subgroup analyses on these specific diseases. Results: The MR evidence supported the causal association of genetic predictors of ADs with an increased risk of sarcoidosis (OR = 1.79, 95% CI = 1.59 to 2.02, P IVW-FE = 1.01 × 10-21), and no reverse causation (OR = 1.05, 95% CI 0.99 to 1.12, P IVW-MRE = 9.88 × 10-2). Furthermore, subgroup analyses indicated that genetic predictors of type 1 diabetes mellitus (T1DM), celiac disease, and inflammatory bowel disease (IBD) were causally linked to an elevated risk of sarcoidosis (All P < 6.25 × 10-3). Conversely, genetic predictors of sarcoidosis showed causal associations with a higher risk of type 1 diabetes mellitus (P < 6.25 × 10-3). Conclusion: The present study established a positive causal relationship between genetic predictors of ADs (e.g. T1DM, celiac disease, and IBD) and the risk of sarcoidosis, with no evidence of reverse causation.

Subcutaneous sarcoidosis: a case series from a single center.

BACKGROUND: Sarcoidosis is a multisystemic granulomatous disease which not only affect the skin but can also involve the lymph nodes, eyes, and lungs. Subcutaneous sarcoidosis (SCS), is a rare form of sarcoidosis which is generally more prevalent in women in their 40s and 50s, characterized by subcutaneous, flesh-colored nodules, mostly localized on the limbs. A retrospective study to investigate clinical features and response to treatment in patients affected by SCS. METHODS: All patients with systemic and/or cutaneous sarcoidosis visited in our clinic hospital between 2012 and 2022. Out of this group, clinical features, and management of SCS patients were analyzed. RESULTS: Out of 102 patients with specific lesions of cutaneous sarcoidosis, with or without systemic involvement, 13 (13%) were diagnosed with SCS. CONCLUSIONS: Our study confirms that systemic involvement in SCS is the prevalent finding as expected. Moreover, SCS patients have a relatively good prognosis, and systemic treatment does not differ from first-line therapies for cutaneous sarcoidosis.

[Sarcoid Peripheral Neuropathy and Myopathy: A Diagnostic and Therapeutic Challenge].

Sarcoidosis is an idiopathic granulomatous multi-organ disease, primarily affecting the respiratory system, eyes, and skin, with less involvement in peripheral neurons and muscles. Sarcoid peripheral neuropathy encompasses cranial and spinal nerve impairment. Muscle involvement is often asymptomatic and revealed through imaging. Symptomatic muscle involvement is categorized into three clinical types: nodular myopathy, acute myopathy, and chronic myopathy. The identification of noncaseating granulomas in peripheral nerves or muscles, coupled with the exclusion of other diseases, is essential for establishing a definitive diagnosis of sarcoid peripheral neuropathy and myopathy. Sarcoid neuropathy and myopathy are typically managed with high-dose corticosteroids, immunosuppressants, or a combination of both. In recent times, the use of TNF-alpha inhibitors has notably increased. However, these conditions often exhibit resistance to treatment and may necessitate prolonged therapeutic interventions. Therefore, comprehensive examinations should be conducted before considering immunotherapy. Due to the rarity of these conditions, research on manifestation-specific treatments is lacking, and standard treatments for sarcoid neuropathy and myopathy have not been established. Additional treatment options for sarcoid neuropathy and myopathy are expected to become available in the future.

Obstructive Sleep Apnea and Sarcoidosis Interactions.

Obstructive sleep apnea (OSA) is very prevalent in sarcoidosis patients. Sarcoidosis of the upper respiratory tract may affect upper airway patency and increase the risk of OSA. Weight gain due to steroid use, upper airway myopathy due to steroids and sarcoidosis itself, and interstitial lung disease with decreased upper airway patency are other reasons for the higher OSA prevalence seen in sarcoidosis. Several clinical manifestations such as fatigue, hypersomnolence, cognitive deficits, and pulmonary hypertension are common to both OSA and sarcoidosis. Therefore, early screening and treatment for OSA can improve symptoms and overall patient quality of life.

Decreased serpin C1 in extracellular vesicles predicts response to methotrexate treatment in patients with pulmonary sarcoidosis.

BACKGROUND: Sarcoidosis is a systemic granulomatous disease of unknown etiology primarily affecting the lungs. Treatment is needed when disease symptoms worsen and organ function deteriorates. In pulmonary sarcoidosis, prednisone and methotrexate (MTX) are the most common anti-inflammatory therapies. However, there is large inter-patient variability in response to treatment, and predictive response markers are currently lacking. OBJECTIVE: In this study, we investigated the predictive potential of biomarkers in extracellular vesicles (EVs) isolated from biobanked serum of patients with pulmonary sarcoidosis stored prior to start of therapy. METHODS: Protein concentrations of a four-protein test panel of inflammatory proteins were measured in a discovery (n = 16) and replication (n = 129) cohort of patients with sarcoidosis and 47 healthy controls. Response to therapy was defined as an improvement of the absolute score of > 5% forced vital capacity (FVC) and/or > 10% diffusion lung of carbon monoxide (DLCO) after 24 weeks compared to baseline (before treatment). RESULTS: Serum protein levels differed between EV fractions and serum, and between sarcoidosis cases and controls. Serpin C1 concentrations in the low density lipid particle EV fraction were lower at baseline in the group of patients with a good response to MTX treatment in both the discovery cohort (p = 0.059) and in the replication cohort (p = 0.032). EV Serpin C1 showed to be a significant predictor for response to treatment with MTX (OR 0.4; p = 0.032). CONCLUSION: This study shows that proteins isolated from EVs harbor a distinct signal and have potential as new predictive therapy response biomarkers in sarcoidosis.

Adalimumab as treatment for neurosarcoidosis: A case series.

Sarcoidosis is a disease characterized by non-caseating granulomas that can involve the central nervous system as neurosarcoidosis. This challenging disease is currently managed with high dose steroids, and sometimes the addition of infliximab. Other TNA-alpha inhibitors have not been studied as rigorously. We discovered ten neurosarcoidosis patients who were on an alternative TNA-alpha inhibitor, adalimumab. Eight patients had a positive response clinically and radiographically to adalimumab.

Blau Syndrome With Delayed Cutaneous Manifestations: A Case Report.

ABSTRACT: Blau syndrome is a rare familial autoinflammatory disorder characterized by the triad of granulomatous dermatitis, polyarthritis, and uveitis. Blau syndrome exhibits an autosomal dominant inheritance pattern and can be caused by a gain-of-function mutation in nucleotide-binding oligomerization domain 2 (NOD2), a member of the NOD-like receptor family of pattern recognition receptors. Mutations in NOD2 cause upregulation of inflammatory cytokines and resultant autoinflammation. Because of the rarity of this condition and early onset of symptoms, Blau syndrome may be misdiagnosed as juvenile idiopathic arthritis. We present a case of a 37-year-old male patient with a long-documented history of juvenile idiopathic arthritis and uveitis, who developed an asymptomatic eruption of pink papules on the trunk and upper extremities. A biopsy demonstrated noncaseating, well-formed dermal granulomas with relatively sparse lymphocytic inflammation and Langerhans-type giant cells. Genetic testing confirmed a mutation in NOD2. Based on the patient's clinical history, histologic findings, genetic testing, the diagnosis of Blau syndrome was made.

Comparing outcomes of an 'early' versus 'late' diagnosis of cardiac sarcoidosis following a baseline presentation of high-grade atrioventricular block.

BACKGROUND: There is a paucity of evidence on impact of a delay in Cardiac Sarcoidosis (CS) diagnosis after high-grade atrioventricular-block (AVB) and this study aims to fill this void. METHODS: Consecutive CS patients (n = 77) with high grade AVB referred to one specialist hospital in London between February 2007 to February 2023 were retrospectively reviewed. The median time from AVB to diagnosing CS (112 days) was used to define the Early (n = 38) and Late (n = 39) cohorts. The primary endpoint was a composite of all-cause mortality, cardiac transplantation, ventricular arrhythmic events or heart failure hospitalisation. Secondary endpoints included difference in maintenance prednisolone dose, need for cardiac device upgrade and device complications. RESULTS: The mean age of the cohort was 54.4 (±10.6) years of whom 64 % were male and 81 % Caucasian. After a mean follow up of 54.9 (±45.3) months, the primary endpoint was reached by more patients from the Late cohort (16/39 vs. 6/38, p = 0.02; multivariable HR 6.9; 95 %CI 1.5-32.2, p = 0.01). Early Group were more likely to have received an Implantable Cardioverter Defibrillator or Cardiac Resynchronisation Therapy-defibrillator as index device after AVB (19/38 vs. 6/39; p < 0.01) and had fewer device upgrades (19/38 vs. 30/39, p = 0.01) and a trend towards fewer device complications (1 vs. 5, p = 0.20). The maintenance dose of prednisolone was significantly higher in Late Group [20.7(±9.7) mg vs. 15.3(±7.9) mg, p = 0.02]. CONCLUSION: A late diagnosis of CS was associated with more adverse events, a greater probability of needing a device upgrade and required higher maintenance steroid dose.

Radiographical bony lesions after discontinuation of immunosuppressant therapy: bone involvement in sarcoidosis.

We describe a patient who had failed renal transplant after 13 years, eventually requiring a graft nephrectomy and discontinuation of immunosuppressive therapy, including antithymocyte globulin, tacrolimus and mycophenolate while on steroid avoidance protocol. Within a few months of complete discontinuation of the immunosuppressive medications, she developed lower back pain associated with numbness in her right anterolateral thigh. The radiological imaging demonstrated multiple bony lesions throughout her axial and appendicular skeleton with normal pulmonary findings. A computerised tomography-guided bone biopsy from the left iliac crest revealed fragments of bone with granulomatous inflammation, thus making the diagnosis of extrapulmonary sarcoidosis. Initiating treatment with prednisone resulted in near-complete resolution of symptoms. Long-term immunosuppressive therapy is administered to all renal transplant recipients to help prevent acute rejection and loss of renal allograft. This case highlights that immunosuppressants can conceal the presence of underlying conditions in transplant patients.

Choroidal manifestations of non-ocular sarcoidosis: an enhanced depth imaging OCT study.

BACKGROUND: Although choroidal thickening was reported as a sign of active inflammation in ocular sarcoidosis, there has been no research on the choroidal changes in non-ocular sarcoidosis (defined as systemic sarcoidosis without overt clinical signs of ocular involvement). Therefore, this study aimed to investigate choroidal structural changes in patients with non-ocular sarcoidosis. METHODS: This retrospective case-control study was conducted at Asan Medical Center, a tertiary referral center. We evaluated 30 eyes with non-ocular sarcoidosis and their age- and spherical equivalent-matched healthy control eyes. The subfoveal choroidal thickness, area ratio (Sattler layer-choriocapillaris complex [SLCC] area to Haller layer [HL] area), and choroidal vascularity index (CVI, luminal area to choroidal area) were analyzed using enhanced depth imaging in optical coherence tomography. Systemic and ocular factors associated with the choroidal thickness were investigated. RESULTS: Compared with the healthy control group, the non-ocular sarcoidosis group had significantly thicker subfoveal choroid (total and all sublayers [SLCC and HL]) and lower area ratio. There were no significant differences in the CVIs at all sublayers between groups. In the non-ocular sarcoidosis group, eyes under oral steroid treatment had thinner choroid than eyes under observation. In the control group, eyes with older age and more myopic spherical equivalent had thinner choroidal thickness. CONCLUSION: Total and all sublayers of the subfoveal choroid were significantly thicker without significant vascularity changes in non-ocular sarcoidosis eyes than in healthy control eyes. The degree of choroidal thickening was disproportionally greater at HL than at SLCC. These characteristic choroidal changes may be the subclinical manifestations in non-ocular sarcoidosis.

Organ involvement in newly diagnosed sarcoidosis patients in the Netherlands: The first large European multicentre prospective study.

BACKGROUND: Clinical presentation and prevalence of organ involvement is highly variable in sarcoidosis and depends on ethnic, genetic and geographical factors. These data are not extensively studied in a Dutch population. AIM: To determine the prevalence of organ involvement and the indication for systemic immunosuppressive therapy in newly diagnosed sarcoidosis patients in the Netherlands. METHODS: Two large Dutch teaching hospitals participated in this prospective cohort study. All adult patients with newly diagnosed sarcoidosis were prospectively included and a standardized work-up was performed. Organ involvement was defined using the WASOG instrument. RESULTS: Between 2015 and 2020, a total of 330 patients were included, 55% were male, mean age was 46 (SD 14) years. Most of them were white (76%). Pulmonary involvement including thoracic lymph node enlargement was present in 316 patients (96%). Pulmonary parenchymal disease was present in 156 patients (47%). Ten patients (3%) had radiological signs of pulmonary fibrosis. Cutaneous sarcoidosis was present in 74 patients (23%). Routine ophthalmological screening revealed uveitis in 29 patients (12%, n = 256)). Cardiac and neurosarcoidosis were diagnosed in respectively five (2%) and six patients (2%). Renal involvement was observed in 11 (3%) patients. Hypercalcaemia and hypercalciuria were observed in 29 (10%) and 48 (26%, n = 182) patients, respectively. Hepatic involvement was found in 6 patients (2%). In 30% of the patients, systemic immunosuppressive treatment was started at diagnosis. CONCLUSIONS: High-risk organ involvement in sarcoidosis is uncommon at diagnosis. Indication for systemic immunosuppressive therapy was present in a minority of patients.