EULAR study group on 'MHC-I-opathy': identifying disease-overarching mechanisms across disciplines and borders.

The 'MHC-I (major histocompatibility complex class I)-opathy' concept describes a family of inflammatory conditions with overlapping clinical manifestations and a strong genetic link to the MHC-I antigen presentation pathway. Classical MHC-I-opathies such as spondyloarthritis, Behçet's disease, psoriasis and birdshot uveitis are widely recognised for their strong association with certain MHC-I alleles and gene variants of the antigen processing aminopeptidases ERAP1 and ERAP2 that implicates altered MHC-I peptide presentation to CD8+T cells in the pathogenesis. Progress in understanding the cause and treatment of these disorders is hampered by patient phenotypic heterogeneity and lack of systematic investigation of the MHC-I pathway.Here, we discuss new insights into the biology of MHC-I-opathies that strongly advocate for disease-overarching and integrated molecular and clinical investigation to decipher underlying disease mechanisms. Because this requires transformative multidisciplinary collaboration, we introduce the EULAR study group on MHC-I-opathies to unite clinical expertise in rheumatology, dermatology and ophthalmology, with fundamental and translational researchers from multiple disciplines such as immunology, genomics and proteomics, alongside patient partners. We prioritise standardisation of disease phenotypes and scientific nomenclature and propose interdisciplinary genetic and translational studies to exploit emerging therapeutic strategies to understand MHC-I-mediated disease mechanisms. These collaborative efforts are required to address outstanding questions in the etiopathogenesis of MHC-I-opathies towards improving patient treatment and prognostication.

Validation of the new classification criteria for systemic lupus erythematosus on a patient cohort from a national referral center: a retrospective study.

AIM: To validate Systemic Lupus International Collaborating Clinics (SLICC)-12 and American College of Rheumatology (ACR)-97 classification criteria on a patient cohort from the University Hospital Center Zagreb. METHODS: This retrospective study, conducted from 2014 to 2016, involved 308 patients with systemic lupus erythematosus (SLE) (n=146) and SLE-allied conditions (n=162). Patients' medical charts were evaluated by an expert rheumatologist to confirm the clinical diagnosis, regardless of the number of the ACR-97 criteria met. Overall sensitivity and specificity, as well as the sensitivity and specificity according to disease duration, were compared between ACR-97 and SLICC-12 classifications. Predictive value for SLE for both classifications was assessed using logistic regression and receiver operating characteristic (ROC) curves. RESULTS: The SLICC-12 criteria had significantly higher sensitivity in early disase, which increased with disease duration. The ACR-97 criteria had higher specificity. The specificity of the SLICC-12 criteria was low and decreased with disease duration. Regression analysis demonstrated the superiority of the SLICC-12 classification criteria over the ACR-97 criteria, with areas under the ROC curve of 0.801 and 0.780, respectively. CONCLUSION: Although the SLICC-12 criteria were superior to the ACR-97 and were more sensitive for diagnosing early SLE, their specificity in our population was too low. The sensitivity of the SLICC-12 classification is increased by better defined clinical features within each criterion. Our results contribute to the current initiative for developing new criteria for SLE.

[Pregnant patient with rheumatoid arthritis treated with methotrexate and infliximab].

Tumor necrosis factor-alpha inhibitors have become an established therapeutic regimen for patients with rheumatoid arthritis. Regarding their harmful potential they are classified as category B medications. Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women. Disease-modifying antirheumatic drugs (DMARDs) are often used in combination with biological therapy and treatment with methotrexate has shown good results. This antimetabolite is classified as a category X drug and its teratogenic effect is well known. The incidence of inflammatory rheumatic diseases is significantly higher in women. There are many reports on pregnant patients treated with biological therapy, oft en in combination with DMARDs. The effects of such a therapy on reproductive health is a theme of debate, with controversial views on the matter. We present a patient with rheumatoid arthritis whose pregnancy was discovered at 31 weeks of gestation. During that period she had been treated with methotrexate and infliximab, with no adverse effects.

GIANT CELL AORTITIS DIAGNOSED WITH PET/CT - PARANEOPLASTIC SYNDROME?

Vasculitides are heterogenic group of autoimmune connective tissue diseases which often present difficulties in early diagnosing. Giant cell arteritis is vasculitis of large and medium arteries. It predominantly presents with symptoms of affection of the external carotid artery branches. Furthermore, the only symptoms can be constitutional. In clinical practice, vasculitides are sometimes considered as paraneoplastic, but no definite association with malignancies has been established and the mechanisms are still debated. The gold standard for diagnosing giant cell arteritis is a positive temporal artery biopsy, but the results can often be false negative. Additionally, more than half of the patients have aorta and its main branches affected. Considering aforementioned, imaging studies are essential in confirming large-vessel vasculitis, amongst which is highly sensitive PET/CT. We present the case of a 70-year-old female patient with constitutional symptoms and elevated sedimentation rate. After extensive diagnostic tests, she was admitted to our Rheumatology unit. Aortitis of the abdominal aorta has been confirmed by PET/CT and after the introduction of glucocorticoids the disease soon went into clinical and laboratory remission. Shortly after aortitis has been diagnosed, lung carcinoma was revealed of which the patient died. At the time of the comprehensive diagnostics, there was no reasonable doubt for underlying malignoma. To the best of our knowledge, there are no recent publications concerning giant cell arteritis and neoplastic processes in the context of up-to-date non-invasive diagnostic methods (i.e. PET/CT). In the light of previous research results, we underline that the sensitivity of PET/CT is not satisfactory when estimating cancer dissemination in non-enlarged lymph nodes and that its value can at times be overestimated.

[A patient with rheumatoid arthritis and primary biliary cirrhosis successfully treated with adalimumab]. / Uspjesna primjena adalimumaba u bolesnice oboljele od reumatoidnog artritisa i primarne bilijarne ciroze.

Rheumatoid arthritis and primary biliary cirrhosis coexist in up to 6% of cases. Tumor necrosis factor alpha seems to have an important role in the pathogenesis of both diseases. Tumor necrosis factor alpha inhibitors have become an established therapeutic regimen for patients with rheumatoid arthritis. The only approved drug for primary biliary cirrhosis is ursodeoxycholic acid. We describe the case of a female patient with both rheumatoid arthritis and primary biliary cirrhosis in a long term remission of both diseases induced with adalimumab. This case report is an important addendum to a few published similar reports.

Vitamin D serum level, disease activity and functional ability in different rheumatic patients.

BACKGROUND: The aim of the study was to determine the serum vitamin D levels in patients with psoriatic arthritis (PsA) and compare it with patients with rheumatoid arthritis (RA) and with osteoarthritis (OA), as well as to explore the relationship of the vitamin D level with indices of disease activity and functional ability in a real-life setting in a South-European country. METHODS: In a cross-sectional study, 120 adult patients with established diagnosis of PsA, RA and OA were consecutively enrolled. Serum 25-hydroxyvitamin D and intact parathyroid hormone were determined. Parameters of disease activity and functional ability were obtained using standard instruments. RESULTS: Serum vitamin D insufficiency (≤ 75 nmol/L) was found in 74% of patients with PsA, 94% patients with RA and 97% of patients with OA, whereas vitamin D deficiency (≤ 25 nmol/L) was found in 13% of patients with PsA, 39% of patients with RA and in 38% of patients with OA. Compared with RA, patients with PsA had significantly higher serum vitamin D (P = 0.002), and when controlling for age and gender, their serum vitamin D level was significantly associated with disease activity and functional activity. CONCLUSIONS: In the group of rheumatic patients, a high prevalence of serum vitamin D insufficiency/deficiency was found regardless of the type of arthritis. Patients with PsA might have higher levels of vitamin D than patients with RA, and this was associated with disease activity and functional ability. The results of this study indicate that prophylactic supplementation with vitamin D might be recommended for all rheumatic patients.

Eosinophilia-myalgia syndrome induced by excessive L-tryptophan intake from cashew nuts.

Eosinophilia is characterized by more than 0.5 × 109 eosinophils per liter in the full blood count. A wide range of conditions, from asthma to parasitic infections, autoimmune diseases, and certain forms of cancer, have been known to trigger abnormally high amount of eosinophils. It is essential to reach the correct diagnosis and treat the underlying disease aggresively. Definition of the eosinophilia-myalgia syndrome was offered in 1980s by Centers for Disease Control and Prevention for surveillance purposes, and criteria were revised in 2001, with high specificity. We report a case of 59-year old female who started a special weight-reducing diet regimen that included excessive cashew nut ingestion. Several months after she has presented with periferal blood eosinophilia and constitutional symptoms. Detailed work-up has not found elements for haematological, systemic autoimmune, neoplastic or infectious disease. She was diagnosed with eosinophilia-myalgia syndrome due to extreme L-tryptophan intake, a compound found in the cashew nut's oil. She responded well to cashew nut withdrawal and steroid therapy. In the follow-up period she remained stable with normal eosinophil count and there was not a need for any specific therapy.