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.

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 [β= 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.

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.