Does Eta Protein Differentiate Rheumatoid Arthritis from Psoriatic Arthritis?

AIM: The clinical symptoms and laboratory markers of Rheumatoid Arthritis (RA) and Psoriatic Arthritis (PsA) can be very similar, so making a differential diagnosis between these two diseases is often difficult. Serological parameters to be used in differential diagnosis can guide the clinician. This study aimed to investigate the usability of 14-3-3η (eta) protein as a biomarker in the differential diagnosis of PsA and RA, and the relationships between eta protein and disease activity scores and joint erosions in PsA and RA. METHODS: 54 PsA patients, 53 RA patients, and 56 healthy individuals were included in this study. The ELISA (Enzyme-Linked ImunoSorbent Assay) kit was used as a quantitative sandwich enzyme immunoassay technique to detect human eta protein levels. Receiver- operating Characteristic (ROC) curves analysis was used to determine the sensitivity and specificity of the eta protein. RESULTS: Eta protein levels were found to be significantly higher in the RA group than in the PsA [B: -0.341, OR (95% CI): 0.711 (0.556-0.909), p: 0.007] and control [B: -0.225, OR (95% CI): 0.798 (0.641-0.995), p: 0.045] groups. Eta protein median values were significantly higher in patients with joint erosion than in those without [ß= 0.151, OR (95% CI): 1.163 (1.003-1.349), p: 0.046]. CONCLUSION: Eta protein levels are higher in the serum of RA patients than PsA and are associated with joint erosion. Eta protein may be a potential biomarker in the differential diagnosis of RA and PsA. It may represent a possible therapeutic step in the pathophysiological pathways in the development of joint erosion.

Effects of intrauterine device use on attack frequency and severity in woman of reproductive age with familial Mediterranean fever.

AIM: Familial Mediterranean fever (FMF) is the most common inherited autoinflammatory disease in the world. There are known triggers to initiate an FMF attack, yet potential effects of intrauterine devices (IUD) in women of reproductive age have not been evaluated before. METHOD: Consecutive female patients with FMF who ever used IUD over the age of 18 were enrolled. Female patients with FMF were sub grouped according to the type of IUD they use. FMF attack frequency, severity, duration, presence of dysmenorrhea, severity of dysmenorrhea, having attacks during menstruation before and after IUD use were questioned. Demographic and clinical data were collected from hospital database. RESULTS: When all patients with IUD use were evaluated, it was found that the frequency of attacks increased after IUD insertion at 3rd and 12th months (median [min-max] attack frequency at 3rd month, 1 (0-3) vs 1 (0-6), p = 0.002, median [min-max] attack frequency at 12th month, 2 (0-12) vs 3.5 (0-18), p = 0.028). Attack severity measured by VAS pain was also significantly increased. Attack duration and menstrual pain was similar before and after IUD use. Attack frequency at 3rd and 12th months, attack severity and menstrual pain was all increased significantly in Cu-IUD users, whereas none of these parameters deteriorated in LNG-IUD group. CONCLUSION: IUD use, especially Cu-IUD, may increase the frequency and severity of attacks in female patients with FMF. Clinicians may benefit from considering LGN-IUD if IUDs are preferred as contraception in women of childbearing age with FMF.

The thiol/disulfide balance is shifted towards oxidation in psoriatic arthritis compared to controls and is associated with higher disease activity.

OBJECTIVE: This study was designed to compare thiol/disulfide and ischemia-modified albumin (IMA) levels between psoriatic arthritis (PsA) and healthy controls and evaluate the correlation between these molecules and the disease activity scores used in PsA. METHODS: A total of 63 PsA patients and 49 healthy volunteers were included in the study. Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), modified disease activity score 28 (DAS28), and Bath Ankylosing Spondylitis Functional Index (BASFI) scores were used as disease activity indices for PsA patients. Calculations of native thiol (-SH), disulfide (-SS), and total thiol (-SH+-SS) molecules were made by the automatic spectrophotometric method, and the albumin cobalt binding test was used to measure IMA levels. RESULTS: In the PsA group, -SS/-SH and -SS/(-SH+-SS) levels were higher and -SH/(-SH+-SS) levels were lower than in controls. In the linear regression analysis, a significant correlation relationship was detected between DAS28-erythrocyte sedimentation rate (ESR) and -SS/(-SH+-SS) (ß = 0.795, CI 95%, 0.196-1.395; P = .010), -SH/(-SH+-SS) (ß = -0.475, CI 95%, 0.114-0.836; P = .010) and IMA (ß = 3.932, CI 95%, 0.859-7.005; P = .013). Additionally, a significant correlation was detected between IMA and BASDAI and BASFI. CONCLUSION: In PsA, thiol/disulfide homeostasis has shifted in favor of disulfide as an oxidative indicator. Serum thiol/disulfide levels are correlated with PsA disease activity indices.

Serum netrin-1 levels are high in Rheumatoid arthritis associated interstitial lung disease.

BACKGROUND: Recent data show that netrin-1 has a role in development of pulmonary fibrosis. This study was aimed to investigate serum netrin-1 level and its relation to interstitial lung disease(ILD) in patients with rheumatoid arthritis (RA). METHOD: 42 RA patients with RA-ILD, 58 RA patients without RA-ILD (RA non-ILD group), and 61 healthy volunteers were included in this study. The modified DAS28-ESR score was used to calculate disease activity in RA patients. Using the quantitative immunoassay method, Serum netrin-1 levels were measured with an ELISA kit (Catalog number: E-EL-H2328; lab science, lot number: GZWTKZ5SWK, Texas, USA). RESULTS: The median value of netrin-1 was found to be significantly higher in the RA-ILD group (82.9 [59.9-124]) compared to both the RA non-ILD group(52.9 [49.5-73.1])(B = -0.006, OR = 0.994, CI 95 %=0.989-0.999, P = 0.018) and the control group(53.5 [49.5-87.5]) (B: -0.005, OR: 0.994, CI 95 %: 0.990-0.999, p: 0.022). A cut-off value of 61.78 for netrin-1 was found to have a sensitivity of 73.8 % and a specificity of 69 % for the diagnosis of RA-ILD (AUC [95 %Cl] = 0.771 [0.679-0.862], p < 0.0001).It was found that high serum netrin-1 level was strongly associated with the RA-usual interstitial pneumonia(UIP) pattern and poorly related to the RA-nonspecific interstitial pneumonia(NSIP) pattern compared to the RA non-ILD group. CONCLUSIONS: Netrin-1 is elevated in the serum of patients with RA-ILD, especially in the UIP pattern. Netrin-1 may be a potential candidate for predicting the development of RA-ILD that should be investigated in the pathophysiological and therapeutic fields.

Renal tubular estrogen ß receptors are expressed at high levels in small vessel vasculitis and are primarily localized in the distal tubule.

This study investigated the possible roles of renal estrogen receptors (ER) in glomerulonephritis associated with small vessel vasculitis. The relationships of ERs were investigated in antineutrophilic cytoplasmic antibody (ANCA)-associated glomerulonephritis and immunoglobulin A (IgA) nephropathy groups, which are small vessel vasculitis subtypes with two different glomerulonephritis development pathophysiologies. The design of this study was prepared as a retrospective cohort study. The study included 42 patients with ANCA-associated vasculitis and 18 with IgA nephropathy in the small vessel vasculitis group. For the control group, intact renal tissues of 28 patients who underwent nephrectomy due to renal cell carcinoma were used. Renal biopsy samples of the groups were stained with ER beta (ß) and ER alpha (α). Tubular ER ß expression score (TERßES) median values were found to be significantly higher in ANCA- associated vasculitis (B = 0.724, OR [95%CI]: 2.064 [1.141-3.731], p = .016) and IgA nephropathy (B = 0.898, OR [95%CI]: 2.454 [1.307-4.609], p = .005) than in intact kidney tissue. It was determined that tubular ERß was most frequently localized in the distal tubule at 57.9% and the second most common in the proximal tubule at 20.4%. The expression of tubular ERß is increased in glomerulonephritis due to small vessel vasculitis. Tubular ERßs are most commonly localized in the distal tubule. Further studies are needed to understand the physiological and pathophysiological effects of altered renal ER levels in small vessel vasculitis.

Predictors of DAPSA28 remission in patients with psoriatic arthritis initiating a first TNF inhibitor: results from 13 European registries.

OBJECTIVES: In bio-naïve patients with PsA initiating a TNF inhibitor (TNFi), we aimed to identify baseline predictors of Disease Activity index for PsA in 28 joints (DAPSA28) remission (primary objective) and DAPSA28 moderate response at 6 months, as well as drug retention at 12 months across 13 European registries. METHODS: Baseline demographic and clinical characteristics were retrieved and the three outcomes investigated per registry and in pooled data, using logistic regression analyses on multiply imputed data. In the pooled cohort, selected predictors that were either consistently positive or negative across all three outcomes were defined as common predictors. RESULTS: In the pooled cohort (n = 13 369), 6-month proportions of remission, moderate response and 12-month drug retention were 25%, 34% and 63% in patients with available data (n = 6954, n = 5275 and n = 13 369, respectively). Five common baseline predictors of remission, moderate response and 12-month drug retention were identified across all three outcomes. The odds ratios (95% CIs) for DAPSA28 remission were: age, per year: 0.97 (0.96-0.98); disease duration, years (<2 years as reference): 2-3 years: 1.20 (0.89-1.60), 4-9 years: 1.42 (1.09-1.84), ≥10 years: 1.66 (1.26-2.20); men vs women: 1.85 (1.54-2.23); CRP of >10 vs ≤10 mg/l: 1.52 (1.22-1.89) and 1 mm increase in patient fatigue score: 0.99 (0.98-0.99). CONCLUSION: Baseline predictors of remission, response and adherence to TNFi therapy were identified, of which five were common for all three outcomes, indicating that the predictors emerging from our pooled cohort may be considered generalizable from country level to disease level.

Non-criteria autoantibodies in antiphospholipid syndrome may be associated with underlying disease activity.

BACKGROUND: Antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized by persistent antiphospholipid antibodies (aPLs) with arterial and venous thrombosis and/or pregnancy morbidity. In recent years, several studies have highlighted the potential role of non-criteria aPL in diagnosing APS patients. AIM: This study aimed to determine the association of the presence of non-criteria aPL antibodies to the clinical and laboratory features of patients with a diagnosis of APS. METHODS: Eighty patients diagnosed with APS and under observation in the rheumatology clinic of Ankara City Hospital were assessed. Patient demographic and clinical features were meticulously recorded. Non-criteria antibodies tested in our center included antiphosphatidylserine IgA, antiphosphatidylserine IgM, beta 2 glycoprotein IgA, anti-cardiolipin IgA, antiphospholipid antibody IgG, and antiphospholipid antibody IgM. Antibodies from patients who were tested for at least one non-criteria antibody were documented. RESULTS: Out of 80 patients, 55 (68.8%) were tested for at least one non-criteria antibody, and 29 of those patients (52.7%) tested positive for at least one non-criteria antibody. The antiphospholipid antibody IgM and the beta 2 glycoprotein IgA were the most commonly tested non-criteria antibodies. Patients with non-criteria antibody positivity had a higher frequency of Ds DNA positivity and low complement (62.0% vs. 35.0%, p = 0.042; 69.0% vs. 38.0%, p = 0.023), respectively. In addition, positivity for anti-cardiolipin IgG and b2 glycoprotein IgG was significantly higher in the group positive for non-criteria antibodies (79% vs. 31%, p ≤ 0.001; 72.0% vs. 19%, p ≤ 0.001). There was no significant difference between the clinical features of patients with at least one positivity for non-criteria antibodies and those without. CONCLUSION: Systemic lupus erythematosus (SLE) is the most commonly associated disease with APS, being present in approximately 35% of cases [1]. Since the majority of the patient group in our study had APS that was secondary to SLE, non-criteria antibody positivity may be linked to the immunological activity of SLE. Large multicenter studies are necessary to investigate the clinical significance of isolated/combined positivity for criterion/non-criteria aPLs.

Renal tubular and glomerular estrogen receptor ß levels are lower in lupus nephritis than in familial Mediterranean fever-associated renal amyloidosis.

BACKGROUND: Estrogen has been thought to play an essential role in the disease pathogenesis of systemic lupus erythematosus, which is 9-10 times more prevalent in the female population. It has been shown that irregular estrogen/estrogen receptor signaling pathways may contribute to the pathophysiology of various renal diseases. In this study, we compared renal estrogen receptors between lupus nephritis, familial Mediterranean fever-associated renal amyloidosis, ANCA-associated nephritis, and intact kidney to investigate their role in the pathophysiology of renal diseases. METHODS: This study was designed as a retrospective cohort study. Thirty systemic lupus erythematosus patients with lupus nephritis, 12 familial Mediterranean fever amyloidosis and 10 ANCA-associated glomerulonephrites, and 14 individuals with normal renal histology were included in the study. RESULTS: Tubular estrogen receptor ß expression score was found to be significantly higher in the familial Mediterranean fever [5 (1-8)] group than in the lupus nephritis [0 (0-1)] (B = 1.385, OR = 3.996, CI %95 = 1.805-8.846, p = .001) and ANCA [4 (1-6.5)] (B = -1.431, OR = 0.239, CI 95% = 0.093-0.614, p = .003) groups. A significant correlation was found between serum creatinine values and tubular estrogen receptor ß expression score (OR = 0.565, CI 95% = 0.622-1.402, p < .0001). In ANCA-associated glomerulonephritis, a significant relationship was found between fibro cellular crescents in renal biopsy and glomerular estrogen receptor ß expression score (OR = 0.247, CI 95% = 0.11-0.999, p = .045) and tubular estrogen receptor ß expression score (OR = 0.282, CI 95% = -0.180-2.812, p = .026). CONCLUSIONS: This study showed that tubular estrogen receptor ß expression score was elevated in familial Mediterranean fever amyloidosis and correlated with serum creatinine levels and renal crescents.

Neurological Involvement in Patients with Primary Sjögren's Syndrome: A Retrospective Cross-Sectional Study.

Background: To determine the rate and types of neurological involvement in patients with primary Sjögren's syndrome (pSS) and to evaluate predictive clinical and immunologic features of neurological involvement. Methods: We retrospectively assessed 2127 patients with an ICD-10 code for Sjögren recorded in the hospital database. Among these patients, those meeting the pSS classification criteria and having neurological symptoms and an objective evaluation accordingly were enrolled. After comparing the patients with and without neurological involvement, peripheral and central involvement subtypes were also compared within themselves. Results: A total of 199 pSS patients were enrolled and neurological involvement was found in 31.6%. Peripheral nervous system (PNS) involvement was found in 23.5% of the patients, and central nervous system (CNS) involvement was found in 34.3%. Patients with neurological involvement had a higher frequency of Schirmer's test, anti-Ro/SS-A and anti-La/SS-B positivity and the presence of interstitial lung disease, articular involvement, lymphadenopathy, anemia and hypocomplementemia than patients without those. In multivariate regression analysis, only articular involvement had a higher risk for the development of neurologic involvement [OR 10.01 (4.18-23.97), P 0.0001]. Among the patients with PNS, the frequency of anti-Ro/SS-A positivity, low C3 and Schirmer's test positivity were statistically increased compared to those who were not in PNS (P = 0.032, P = 0.044, and P = 0.029, respectively). When compared in terms of CNS involvement, patients with CNS involvement were younger, had a shorter disease duration, and had a higher frequency of anti-Ro/SS-A positivity than patients without those (P = 0.041, P = 0.027, and P = 0.046, respectively). Conclusions: In our study, it was shown that one third of the symptomatic pSS patients had objective neurological involvement. The presence of neurological symptoms should be considered, especially in patients with articular involvement in pSS.

Vascular Involvement in Behcet's Disease: An Evaluation of 147 Cases and Literature Review.

Objectives: Behcet's disease (BD) is characterized by systemic vasculitis with inflammation that can affect various body organs. In BD, vasculitis primarily manifests with venous involvement, distinguishing it from other forms of systemic vasculitis. Methods: We retrospectively analyzed the demographic and clinical characteristics of 147 patients diagnosed with vascular BD in our center. Results: Vascular BD cases accounted for 25.0% (147 out of 589) of all BD patients. A statistically significant correlation was found between gender and vascular involvement that was seen predominantly in males (76.9%). In 71 patients, a vascular event developed during follow-up for BD, while in 76 patients the disease was diagnosed after the occurrence of a vascular event (51.7%). The most common vascular event was deep vein thrombosis in the lower extremities (69.4%). Arterial involvement was primarily observed in the pulmonary arteries (12.9%). Patients with lower extremity deep vein thrombosis tended to be younger, while those with pulmonary artery involvement were typically older. Overall, veins were affected 4.5 times more frequently than arteries. Conclusion: The prevalent type of venous involvement was deep vein thrombosis in the lower extremities. Thrombotic events in BD cannot be solely attributed to abnormalities in thrombotic factors. The treatment of thrombotic events in BD remains contentious, with anticoagulant efficacy being debated and immunosuppressive therapy representing the primary treatment approach. Behcet's disease should be considered when a young male patient presents with an arterial or venous vascular event, especially if it is recurrent.

A single-center rheumatology experience of sarcoidosis: observations from 70 patients.

BACKGROUND: The aim of this study is to determine the demographic, clinical and laboratory characteristics of the patients who followed up with the diagnosis of sarcoidosis, to investigate the distribution frequency of rheumatological findings and to examine the disease management from the perspective of rheumatology. METHODS: Patients who were followed up with the diagnosis of sarcoidosis in the rheumatology clinic of Ankara City Hospital between November 2019 and November 2022 were evaluated. Demographic, clinical, radiological, serological, laboratory, and histopathological findings, and rheumatological, systemic, and locomotor system examination findings of the patients were obtained from the medical data registered in the hospital. RESULTS: A total of seventy sarcoidosis patients (48.98 ± 11.78 years, %75 female) were included in the study. Joint involvement was observed in 64.3% of cases, skin involvement in 48.6% of cases, and ocular involvement in 25.7% of cases. The ankle was the most frequently involved joint, followed by the knee and small joints in the foot. Corticosteroids were the most used therapeutic agent, and pulmonary and joint findings were the most common reasons for starting treatment. CONCLUSIONS: Sarcoidosis is a disease that mimics many diseases, misdiagnosis and treatment should be avoided with a good and fast differential diagnosis. Clinicians, especially rheumatologists, should remember sarcoidosis more frequently and keep it in mind in the differential diagnosis.

14-3-3 η ETA protein as a potential marker of joint damage in gout.

INTRODUCTION: The aim of the study is to investigate serum levels of 14-3-3 η (ETA) protein in patients with gout and possible relations with joint damage. METHOD: This cross-sectional study included 43 gout patients and 30 control patients. RESULTS: Serum 14-3-3 η protein levels were significantly higher in gout patients (median [IQR], 3.1 [2.0] vs 2.2 [1.0], p = 0.007). In subgroup analyses of gout patients, serum 14-3-3 η protein levels did not differ between patients with and without a flare, tophaceous disease, elevated CRP and serum uric acid levels and a history of chronic kidney disease; however, were significantly higher in the patients with erosions (Median [IQR], 4.1 [2.7] vs 2.7 [1.5], p = 0.002). According to ROC curve, serum 14-3-3 η protein had 86.0% sensitivity and 30% specifity at a cut-off point of 1.7 ng/mL and had 74.7% sensitivity and 43.3% specifity at a cut-off point of 2.0 ng/mL. CONCLUSION: Our results demonstrated elevated levels of 14-3-3 η protein in gout patients which is more prominent in patients with erosive changes, implying role of 14-3-3 η protein in inflammatory and structural damage related pathways and suggesting a potential as a marker for disease severity.

The administration of methotrexate in patients with Still's disease, "real-life" findings from AIDA Network Still Disease Registry.

OBJECTIVES: To describe clinical characteristics of patients with Still's disease treated with methotrexate (MTX) and to assess drug effectiveness evaluating change in disease activity, reduction of inflammatory markers, and glucocorticoid (GC)-sparing effect. METHODS: Patients with Still's disease treated with MTX were assessed among those included in AIDA Network Still Disease Registry. RESULTS: In this registry, 171 patients with Still's disease were treated with MTX (males 43.3%, age 37.1 ± 16.0 years). They were mainly characterised by joint features and fever without a prominent multiorgan involvement. MTX was administered with GCs in 68.4% of patients, with other conventional synthetic DMARDs in 6.4%, and with biologic DMARDs in 25.1%. A significant reduction of the modified systemic score was observed, and 38.6% patients were codified as being in clinical remission at the end of follow-up. The concomitant administration of a biologic DMARD resulted a predictor of the clinical remission. Furthermore, a reduction of inflammatory markers and ferritin levels was observed following the administration of MTX. Additionally, a marked reduction of the dosage of concomitant GCs was identified, while 36.7% discontinued such drugs. Male gender appeared as a predictor of GC discontinuation. MTX was discontinued in 12.3% of patients because of adverse effects, and in 12.3% for lack of efficacy. CONCLUSIONS: Clinical characteristics of patients with Still's disease treated with MTX were described, mainly joint features and fever without a prominent multiorgan involvement. The clinical usefulness of MTX was reported in reducing the disease activity, decreasing the inflammatory markers, and as GC-sparing agent.

Accelerated kynurenine pathway downregulates immune activation in patients with axial spondyloarthritis.

Various studies reported that the kynurenine (Kyn) pathway plays a pivotal role in regulating the balance between activation and inhibition of the immune system. Proinflammatory cytokines can accelerate the Kyn pathway by altering indoleamine (2, 3)- dioxygenase (IDO) allosteric enzyme activity. Excessive cytokine release and immune system activation have essential roles in the pathogenesis of axial spondyloarthritis (axSpA). We aimed to investigate the relationship of the Kyn pathway with proinflammatory cytokines and with the severity of the disease in patients with axSpA. The study included 104 patients with axSpA and 54 healthy volunteers. The severity of the disease was determined by Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). The Kyn pathway was evaluated by IDO activity calculated with Kyn/Tryptophan (Trp) ratio. Plasma Trp and Kyn concentrations were measured with tandem mass spectrometry. Serum IL 17/23 and IFN-γ concentrations were measured with ELISA. These groups were compared in terms of IDO, IL-17, IL-23, IFN-γ, and BASDAI. Plasma IDO activity was significantly increased, however, serum IL-17, IL-23, and IFN-γ levels were significantly decreased in patients compared to healthy volunteers. While IFN-γ was positively correlated with the severity of the disease (p = 0.02), it also had a significant inverse correlation with IDO activity (p < 0.001). However, these correlations are weak. As a result of this study, the Kyn pathway is accelerated and proinflammatory cytokine levels are decreased in patients with axSpA. All of these results with an indirect weak negative association between high IDO and low disease activity suggest that an accelerated Kyn pathway may limit the immune system activation in axSpA disease.

Rheumatology experience with FDG PET / CT in inflammation of unknown origin: a single - centre report for determining factors associated with diagnostic precision.

BACKGROUND / AIM: The use of PET / CT is becoming more common in the elucidation of inflammatory processes in which the underlying cause cannot be determined by conventional examinations. Although PET / CT is an effective method for detecting inflammatory foci, the precise diagnosis may not be obtained in all cases. In addition, considering factors such as radiation exposure and cost, it becomes important to identify patients who can get results with PET / CT. In this study, it was aimed to examine the factors that can predict the differential diagnostic value of PET / CT by retrospectively scanning patients who underwent PET / CT for inflammation of unknown origin (IUO) in rheumatology practice. METHODS: Demographic, clinical and laboratory information of the patients followed up in our clinic and who underwent PET / CT for differential diagnosis were enrolled. Whether they were diagnosed after PET / CT and during the follow - up period, and their diagnoses were examined. RESULTS: A total of 132 patients were included in the study. A previous diagnosis of rheumatic disease was present in 28.8 % of the patients, and a history of malignancy was present in 2.3 % . The patients were divided into three groups: group 1 patients with increased FDG uptake in PET / CT and diagnosis confirmed by PET / CT, group 2 patients with increased FDG uptake in PET / CT but diagnosis was not confirmed, and group 3 patients without increased FDG uptake in PET / CT. Increased FDG uptake in PET / CT was detected in 73 % of the patients. While PET / CT helped the diagnosis in 47 (35.6 %) patients (group 1), it did not help the diagnosis in 85 (64.4 %) (groups 2 and 3). Thirty - one (65.9 %) of the diagnosed patients were diagnosed with a rheumatologic disease. When the 3 groups were compared, male gender, advanced age, CRP levels, presence of constitutional symptoms, SUVmax values and number of different organs with increased FDG uptake were higher in Group 1. Sixty - six percent and 74 % of the patients in groups 2 and 3 were not diagnosed during the follow - up period. No patient in group 3 was diagnosed with malignancy during follow - up. CONCLUSION: PET / CT has high diagnostic value when combined with clinical and laboratory data in the diagnosis of IUO. Our study revealed that various factors can affect the diagnostic value of PET / CT. Similar to the literature, the statistically significant difference in CRP levels shows that patients with high CRP levels are more likely to be diagnosed with an aetiology in PET / CT. Although detection of involvement in PET / CT is not always diagnostic, there was an important finding that no malignancy was detected in the follow - up in any patient without PET / CT involvement. Key points • PET / CT is an effective method for detecting inflammatory foci. • PET / CT has proven to be effective in the diagnosis of rheumatological diseases, the extent of disease and the evaluation of response to treatment. • Indications for the use of PET / CT in the field of rheumatology and the associated factors and clinical features supporting the diagnosis with PET / CT are still to be fully clarified. • In routine practice, with PET / CT, both delays in diagnosis and examinations performed during diagnosis and the cost can be reduced.

COVID-19 disease frequency, risk factors, and re-infection rates in patients with autoimmune rheumatic disease receiving rituximab.

INTRODUCTION: Rituximab, which is used in autoimmune rheumatic diseases (ARD), can cause both an increased risk of development of COVID-19 disease and re-infection due to its potent and long-acting immunosuppression. So, we aimed to evaluate the frequency, risk factors and re-infection rates of COVID-19 in ARD patients receiving rituximab. METHODS: A single-center retrospective study was performed with patients receiving rituximab for ARD in 12 months before the onset of COVID-19 in Turkey. The data regarding severe acute respiratory syndrome-coronavirus 2 reverse transcription polymerized chain reaction (RT-PCR) test, clinical, laboratory, and mortality data of all patients were collected from medical records. Logistic regression analysis was used for predictors of COVID-19 disease. COVID-19 re-infection was defined as RT-PCR positivity and recurrence of acute COVID-19 symptoms after at least 1 negative RT-PCR in patients with clinical improvement. RESULTS: Ninety-eight ARD patients with rituximab were evaluated and 23 (23%) of them had COVID-19. The presence of hypogammaglobulinemia increased the risk of COVID-19 disease 8-fold. COVID-19 pneumonia occurred in 13 (57%) and these patients' age was higher than those without pneumonia (59.6 ± 11.8 vs 44.9 ± 14.2 years, P = 0.013). Mortality due to COVID-19 was 13% and COVID-19 re-infection was seen in 20% of survivors. CONCLUSION: Regardless of the underlying rheumatic disease and organ involvements, hypogammaglobulinemia in ARD could be a risk factor for COVID-19 development, and advanced age could be for COVID-19 severity. Moreover, COVID-19 re-infection rates are high.

Effects of sulfasalazine in axial spondyloarthritis on COVID-19 outcomes: real-life data from a single center.

INTRODUCTION: Compared to biological agents, little is known about the impact of sulfasalazine therapy on COVID-19 outcomes in patients with Axial Spondyloarthritis (AxSpA). Therefore, we aimed to evaluate the COVID-19 severity in AxSpAs receiving sulfasalazine and biologic-agent. MATERIALS AND METHODS: A total of 219 SARS-CoV-2 positive AxSpA patients were retrospectively analyzed. COVID-19 pneumonia, hospitalization rate, and length of stay were used to determine COVID-19 severity. AxSpA patients were mainly grouped and compared as sulfasalazine and non-sulfasalazine. Afterward, we excluded no-treatment patients to reveal the drug's effects more clearly and regrouped AxSpA patients as sulfasalazine-monotherapy (34.3%), biologic-monotherapy (33.7%), and sulfasalazine + biologic (7.3%). RESULTS: Fifty-nine percent of the patients were male and the mean age was 45.0 years. Peripheral arthritis was 35% and uveitis 15%. In total, 41.5% of them have received sulfasalazine and 41.0% biologic agents, and the remaining patients with no AxSpA-specific treatment. In the first comparison, the sulfasalazine group had a higher age, more frequent COVID-19 pneumonia, hospitalization, and longer hospitalization than a non-sulfasalazine group. In the pairwise comparison of 3 treatment groups, the demographic and clinical features, the hospitalization rate and the length of hospital stay were similar but the sulfasalazine-monotherapy group had a higher frequency of COVID-19 pneumonia than the biologic-monotherapy group (23% vs. 7%, p = 0.008). CONCLUSION: Our results imply sulfasalazine may be related to more severe COVID-19 in AxSpA patients. These patients should be followed more carefully in the presence of COVID-19, regardless of reasons such as age, comorbidity, and extra-axial disease, and consideration of discontinuing sulfasalazine maybe even thought.

Evaluation of thiol/disulfide homeostasis in rheumatoid arthritis and disease activity.

BACKGROUND: It has been suggested that the deterioration in the antioxidant defense system due to thiols may cause the pro-oxidant/antioxidant imbalance seen in rheumatoid arthritis (RA). This study was conducted to evaluate thiol/disulfide (-SH/-SS) homeostasis in patients with RA compared to healthy controls, and to validate the limited number of studies examining the relationship between Disease Activity Score-28 (DAS28) and thiol parameters. METHOD: A total of 100 individuals (mean age: 46.3 ± 12.03) consisting of 86 females and 14 males were included in the RA group, and a total of 100 individuals (mean age: 43.3 ± 10.96 years) consisting of 78 females and 22 males were included in the control group. DAS28 was used to assess RA disease activity. -SH/-SS homeostasis parameters were measured using the automated spectrophotometric method described by Erel and Neselioglu. RESULTS: While native thiol (-SH) (p:0.001), total thiol (-SH + -SS) (p < 0.0001) levels and -SH\(-SS + -SH) ratio (p: 0.018) were lower in the RA group compared to the healthy controls, disulfide (-SS) level (p: 0.005)), -SS\-SH (p: 0.001) and -SS\(-SS + -SH) (p: 0.002) ratios were found to be higher. In the control group and the group in remission (defined by DAS28 < 2.6), the median values of -SH (p:0.002) and -SS + -SH (p:0.0008) were found to be significantly higher, and the median value of -SS (p: 0.001) was found to be lower compared to the other DAS28 groups. While a negative correlation was found between DAS28 and -SH (r: -0.243, p: 0.007), a positive correlation was found between DAS28 and -SS (r: 0.316, p: 0.0003), -SS\-SH (r:0.229, p: 0.002) and -SS\(-SS + -SH) (r: 0.285, p: 0.0009). CONCLUSIONS: The plasma thiol antioxidant pool was decreased in RA compared to healthy controls and those with active disease compared to those in remission.

Motor neuron disease in a patient with overlap syndrome (rheumatoid arthritis; systemic lupus erythematosus, Sjogren's syndrome).

Autoimmune rheumatic diseases have their own specific clinical presentation, and can affect multiple systems. Neurological involvement of autoimmune rheumatic diseases may involve both the central and peripheral nervous systems. Inflammation of neural tissue, autoantibody-mediated reactions, and small vessel vasculitis may be effective in the pathogenesis of neuropathy in autoimmune rheumatological diseases. Autoimmune rheumatic disease with pure motor neuron involvement is very rare in the literature. The case is here presented of a 58-year-old female patient who presented with the complaints of increasing pain and weakness in the extremities and was diagnosed with lower motor neuron disease and overlap syndrome. The patient was treated with cyclophosphamide, pulse steroid, hydroxychloroquine and intravenous immunoglobulin. After 3 months of treatment, a significant improvement was observed in the patient's clinical complaints and laboratory parameters. In conclusion, some patients with undiagnosed autoimmune rheumatic diseases may have neurological complaints. Clinicians should investigate patients with such neurological complaints for autoimmune rheumatic diseases.

Elevated Kynurenine Levels in Patients with Primary Sjögren's Syndrome.

OBJECTIVE: We aimed to investigate the plasma levels of tryptophan (Trp) and its metabolites in patients with primary Sjögren's syndrome (pSS). METHODS: The study included 34 pSS patients and 42 healthy individuals, and serum Trp and kynurenine (Kyn) concentrations were measured by liquid chromatography with tandem mass spectrometry. Trp degradation was predicted using the ratio of Kyn and Trp concentrations (Kyn/Trp). RESULTS: In our study, the mean serum Trp concentration was found to be considerably lower in the pSS group than in the control group (P = .001). The levels of Kyn (P = .019) and the Kyn/Trp ratio (P < .001) were significantly higher in the pSS group than in the control group. The Kyn/Trp ratio was negatively correlated with C-reactive protein (r = -0.369, P = .032). CONCLUSION: We found that Kyn pathway metabolism was altered in patients with pSS. This suggests that Trp metabolism may be closely linked to the disease pathogenesis of pSS.