Proliferative Lupus Nephritis Research Articles

STAT3 inhibition ameliorates renal interstitial inflammation in MRL/lpr mice with diffuse proliferative lupus nephritis

Background and objectives Acute kidney injury (AKI) is one of the most common and severe clinical syndromes of diffuse proliferative lupus nephritis (DPLN), of which poor prognosis is indicated by aggravated renal function deterioration. However, the specific therapy and mechanisms of AKI in DPLN remain to be explored. Methods The correlation between AKI and clinical pathological changes in DPLN patients was analyzed. Expression of STAT3 signaling was detected in MRL/lpr mice with DPLN using immunohistochemical staining and immunoblotting. Inhibition of STAT3 activation by combination therapy was assessed in MRL/lpr mice. Results Correlation analysis revealed only the interstitial leukocytes were significantly related to AKI in endocapillary DPLN patients. MRL/lpr mice treated with vehicle, which can recapitulate renal damages of DPLN patients, showed upregulation of STAT3, pSTAT3 and caspase-1 in renal cortex. FLLL32 combined with methylprednisolone therapy significantly inhibited the STAT3 activation, improved acute kidney damage, reduced the interstitial infiltration of inflammatory cells and decreased the AKI incidence in MRL/lpr mice. Conclusion STAT3 activation may play an important role in the pathogenesis of DPLN and the development of AKI. Hence, STAT3 inhibition based on the combination of FLLL32 with methylprednisolone may represent a new strategy for treatment of DPLN with AKI.

#2963 Light chain deposition in the kidney is more frequent in patients with proliferative lupus nephritis

Abstract Background and Aims Light chain deposition in the kidney is an important histologic feature having a significant role in the pathogenesis of glomerular and autoimmune diseases, including lupus nephritis (LN). However, there is no study examining differences in light chain deposition profile between proliferative and non-proliferative LN. Method We have conducted a retrospective cohort study to evaluate the characteristics and prognostic significance of light chain deposition profile in the kidney of subjects with proliferative and non-proliferative LN. We have collected data on demographics, clinical and laboratory parameters and histopathology (light, immunofluorescent and electron microscopy). Lambda domination (LD) was defined as lambda intensity—kappa intensity ≥ +1. SLE was diagnosed using the American College of Rheumatology criteria and renal outcomes per KDIGO guidelines. Proliferative LN was defined as those containing classes III and IV, while all other classes comprised non-proliferative LN. Results A total of 56 patients with biopsy-proven LN were followed up for at least one year after kidney biopsy (79% women, mean age at biopsy 38 ± 13 years). A total of 71% of patients had proliferative LN. Mean number of glomeruli per biopsy sample was 26 ± 12. Mean immunofluorescent intensity was 1.6 ± 1.0 for lambda and 1.8 ± 1.0 for kappa light chain. A total of 42 (75%) patients had light chain deposition in the glomerulus with 4 (7%) having restricted lambda chain deposition and none had restricted kappa chain deposition. Patients with proliferative LN had more frequent light chain deposition in glomeruli than those with non-proliferative lupus (88% vs. 57%, p = 0.049) , with no difference in LD (24% vs. 14%, p = 0.71). There was no difference between frequency of restricted lambda chain deposition between proliferative and non-proliferative LN (5% vs. 17%, p = 0.60). A total of 12 (21%) patients had LD in the glomerulus. When examining renal outcomes at one year post-biopsy, 55% of patients achieved complete response (CR), 30% achieved partial response (PR) and 15% had no response. There were no differences in achievement of remission (CR or PR) between patients with proliferative and non-proliferative LN (87% vs. 90%, p = 0.93). We also found no difference in frequency of light chain deposition and achievement of remission in proliferative or non-proliferative LN (both p>0.05). Conclusion Light chain deposition is prevalent in LN and is more frequent in patients with proliferative LN. Further studies examining their pathophysiologic properties and potential prognostic value are much warranted.

#2682 Evaluation of clinical, pathological findings and treatment outcomes of patients diagnosed with lupus nephritis: a single center experience

Abstract Background and Aim Renal involvement of systemic lupus erythematosus (SLE) is known as lupus nephritis (LN). The prognosis of lupus patients with LN is worse than those without kidney involvement. Renal survival can be improved in patients with lupus nephritis with appropriate and timely treatment. The aim of our study is to compare the clinical and pathological findings of patients diagnosed with LN in our clinic by renal biopsy, the results of the treatment applied in our center, and renal survival with the literature. Method The local ethical committee approved the study design (date: 04/10/2021; reference number: 121/07) and all procedures were conducted in accordance with the Declaration of Helsinki. Forty-four patients diagnosed with lupus nephritis between January 2012 and January 2021 in the Nephrology Department of Ankara Dıskapı Yıldırım Beyazıt Education and Research Hospital were enrolled in this study. Patient data were analyzed retrospectively. Exclusion criteria were as follows: 1) Patients under 18 years of age, 2) patients with follow-up of period less than 6 months and who did not attend regular follow-ups, 3) patients with connective tissue diseases other than SLE. Results The mean age of the study population was 36.0 ± 10.8, and the majority were female. All patients had proteinuria at diagnosis. Class IV LN was the most common (36.4%). Majority of the patients were in the proliferative LN group (65.9%). A significant difference was found between patients diagnosed with proliferative LN (n = 29) and non-proliferative LN (n = 15) in terms of high serum creatinine levels, low serum complement, presence of anti-dsDNA antibodies and active urinary sediment with proliferative LN (p = 0.021, p = 0.024, p = 0.008, p = 0.008). Treatment responses at 6 and 12 months are shown in Table 1. A significant difference was found between the patients who were in complete remission (n = 16) at 12 months and those who were not in remission (n = 27) in terms of low systolic blood pressure and the estimated glomerular filtration rate (eGFR) at the time of diagnosis (p = 0.008, p = 0.016). It was observed that most of the patients who were not in complete remission at 12 months were in the proliferative LN group (p = 0.024). There was no significant difference in the partial and complete remission rates at 6 and 12 months between the group receiving steroids + cyclophosphamide (n = 14) and the group receiving steroid + mycophenolate mofetil (MMF) (n = 15) in the initial treatment of proliferative LN (p>0.05). In the group taking MMF treatment (n = 15) had a shorter time to reach complete remission than the group taking cyclophosphamide treatment, and it was statistically significant (Table 2) (p = 0.048). It was found that end-stage renal disease (ESRD) developed in 9% of the patients and 2 patients died during followed up period. Recurrence was detected in 8 patients, and it was observed that more than half of the patients with relapse could not achieve complete remission at 12 months. Patients with relapse had higher systolic blood pressure and serum total cholesterol level at the time of diagnosis compared to patients without recurrence (p = 0.013, p = 0.045). In addition, patients with relapse were found to have a higher level of proteinuria at the time of diagnosis (p = 0.036). Conclusion Lupus nephritis remains an important source of morbidity and mortality for SLE patients. SLE patients should be regularly examined for renal involvement. About 10-20% of patients diagnosed with lupus nephritis develop ESRD. Early diagnosis of LN and initiating appropriate treatment when diagnosed without delay is important for renal and patient survival. Although there were some different results, most of the statistically significant data in our study were found to be compatible with the existing literature. However, these data need to be confirmed by studies with high patient participation.

#2475 Glomerulonephritis associated with anti -TNF-α therapy

Abstract Background and Aims Biologic agents like tumor necrosis factor α inhibitors/ anti-TNF-α/, IL6 and CD80/26 are widely used in many rheumatologic diseases but these may also elicit effects on renal function. These drugs, as well as rheumatic diseases themselves, can cause autoimmune renal disorders. Though effective on the main inflammatory process the incidence of kidney injury associated with their administration is increasing. Various forms of glomerulopathies have been described in connection with biological therapy - proliferative lupus nephritis, oligo immune necrotizing crescentic glomerulonephritis, membranous glomerulonephritis, IgA nephropathy and others. Method We report the clinical and pathologic findings in two patients with Rheumatoid arthritis and Ankylosing spondylitis on biologic therapy with an anti-TNF-α agent. During the treatment they presented with nephritic syndrome requiring kidney histology. Results Case 1: The first patient is a 52-year-old man diagnosed with ankylosing spondylitis, HLA-B27 positive, 15 years before admission. Four years before admission treatment with Golimumab /anti-TNF-α/ has been initiated. During the follow-up period urine tests revealed proteinuria and hematuria, which required more detailed tests. The patient presented with clinical features of nephritic syndrome, marked lower extremity edema, hematuria, nephrotic range proteinuria, impaired hypertension control. Kidney biopsy revealed membranoproliferative glomerulonephritis. It was assumed that kidney injury was most likely associated with Golimumab therapy. Its administration was discontinued, and therapy was started with pulses of Methylprednisolone 500 mg i.v. in three consecutive days, Cyclophosphamide 500 mg i.v., repeated the second and third month, followed by low steroid doses 0,5 mg/kg with gradual tapering. Mycophenolate Mofetil 1500 mg was started from the third month. General condition and laboratory results improved considerably. The occurrence of stiffness and pain in the sacroiliac joints several months after stopping biologic treatment necessitated the inclusion of Sulfasalazine to the therapy. Initiation of therapy with another class of biologic agent, Anti-IL-17 monoclonal antibody, was discussed with the follow-up rheumatologists. Case 2: The second patient is a 66-year-old woman, with a history of hypertension and essential thrombocythemia, who was diagnosed with seropositive rheumatoid arthritis 3 years before admission, treated with Adalimumab /anti-TNF-α/. Follow-up examinations revealed low-grade proteinuria, hematuria and impaired renal function. Kidney biopsy revealed IgA nephropathy. Following the discontinuation of Adalimumab, the patient was treated with pulses of Methylprednisolone 500 mg i.v. in three consecutive days, Cyclophosphamide 500 mg i.v., repeated the second and third month, followed by low steroid doses 0,5 mg/kg with gradual tapering. Kidney function significantly improved at the third month of treatment and proteinuria was gradually reduced. Initiation of Rituximab /antiCD20/ treatment was discussed with rheumatologists. Conclusion Treatment with biological drugs can cause immune-mediated glomerular disorder/IGD/. These events are rare, and the causative effects of a specific drug is hard to establish. When a patient is suspected of having an IGD, kidney biopsy should be performed for the exact diagnosis. The drug should be discontinued, and the treatment for the new-onset renal disorder should be promptly started. A rechallenge test of the same or a similar drug should be avoided, whereas switching to a different therapy is a reasonable option.

#1393 Urinary soluble CD163 correlates with glomerular inflammation in proliferative lupus nephritis

Abstract Background and Aims Clinical distinction between histologic activity and chronicity in lupus nephritis remains challenging. We sought to evaluate the utility of urinary soluble protein CD613 (usCD163) as a potential biomarker to reflect histologic activity in lupus nephritis (LN). Method Forty-three patients with LN with concurrent determination of usCD163 at the moment of kidney biopsy were included in the study. A first morning void prior to the kidney biopsy was collected and usCD163 was measured by a commercial ELISA assay (EUROIMMUN, Lubeck, DE). Urine CD163 values were normalized to urine creatinine and expressed as ng per mmol of urine creatinine. Results The study cohort had a mean age at the moment of kidney biopsy of 35.3 ± 12.3 years, 81.4% being females. The mean eGFR and 24-h proteinuria were 77.1 ± 33.7 ml/min/1.73 m2 and 3.28 ± 3.23 g/day, respectively. In terms of histological findings, the majority of patients had proliferative LN (class III—34.9%, class IV—34.9%, class IV+V—9.3%), while the median activity and chronicity index were 7 (IQR: 3-11) and 3 (IQR: 1-5), respectively. The median usCD163 normalized to urine creatinine was 616.4 ng/mmol (IQR: 117.6-2363.7). usCD163 significantly correlated with 24-h proteinuria (r = 0.46, p = 0.002), albumin/creatinine ratio (r = 0.61, p < 0.001) and C3 level (r = −0.32, p = 0.03), but not with hematuria (r = 0.26, p = 0.09) or eGFR (r = −0.27, p = 0.07). Regarding the histological parameters, usCD163 significantly correlated with the activity index (AI) and the individual active lesions (with the exception of fibrinoid necrosis), but not with chronicity index or any chronic lesion (Fig. 1). In addition, the level of usCD163 was higher in patients with proliferative LN compared to those with class II or isolated class V LN (Fig. 2). When evaluating the capacity of different variables to discriminate patients with a high AI (≥9), usCD163 outperformed classical clinical or immunological variables, with an area under the curve of 0.71 (95% CI, 0.55-0.86; p = 0.01). At a cutoff of 313 ng/mmol (Youden Index = 0.42), usCD163 had a sensitivity of 88.2% and specificity of 46% to identify patients with a high AI. Patients with an elevated level of usCD163 (≥313 ng/mmol) had higher 24-h proteinuria (4.41 ± 3.4 vs. 1.36 ± 1.74 g/day, p < 0.001), higher AI [10 (IQR: 6-12) vs. 3.5 (IQR: 0-6), p < 0.001] and more frequently class IV LN (48.1% vs. 12.5%, p = 0.02), compared to those with low levels of usCD163. In addition, 4 patients underwent repeat kidney biopsy post-induction therapy. In these patients, serial monitoring showed a normalization of usCD163 levels that paralleled a decrease in both proteinuria and AI. Conclusion Urinary soluble CD163 is a promising non-invasive biomarker for glomerular inflammation and could be used to evaluate histologic activity in patients with LN.

#2172 Maternal, obstetric and perinatal outcomes in pregnant women with lupus nephritis: experience of a tertiary center

Abstract Background and Aims Pregnant patients with systemic lupus erythematosus (SLE) and lupus nephritis (LN) are at particular risk for unfavourable maternal, obstetric and perinatal outcomes, especially if the disease is active. Thus, it is of paramount importance that LN patients have preconceptional counseling in order to optimize care and define the best moment to conceive. Method Observational retrospective study based on the review of medical records of pregnant women with lupus nephritis surveilled at our multidisciplinary maternal-fetal clinic from 2011 to 2023. Results We evaluated 26 gestations in 24 patients. Mean age was 30,8 years (19-40), 21 women were Caucasian, 2 black African, 1 Asian; 10/24 were nulliparous and 6/24 had chronic hypertension (HTUN). Mean baseline SCr was 0,79 mg/dl (0.5-3.5), baseline proteinuria > 1 g/day or <0,5 g/day was present in 3/26 and 22/26 gestations, respectively. Chronic kidney disease (CKD) stage 2, 3 and 5 was present in 1, 2 and 1 gestation respectively; 5/24 patients were APL positive; positive dsDNA and complement consumption at baseline were present in 4/26 and 12/26 gestations, with most patients previously having class IV LN (15/23). Active lupus nephritis during pregnancy occurred in 3 patients: 2 were submitted to medical termination of pregnancy (due to severe pulmonary HTN and renal function deterioration) and 1 was successfully treated with tacrolimus, azathioprine and prednisolone from week 28, and biopsied postpartum. Exposure to teratogenic therapy during the 1st trimester occurred in 3/26 gestations with a mean exposure of 8,5 weeks. Worsening kidney function occurred in 3/24 patients due to PE (1/26 CKD stage 3)/LN (1/26 stage CKD3)/pregnancy hyperfiltration (1/26 CKD stage CKD5), with partial and full renal recovery in 2 CKD stage 3 patients and dialysis initiation in the CKD stage 5 patient at 19 weeks (urea levels > 100 mg/dL). De novo proteinuria occurred in 3/24 patients (due to LN) and worsening proteinuria in 6/24 patients (PE 2/6; pregnancy hyperfiltration 4/6). De novo or worsening HTN occurred in 3/26 gestations. Immunosuppression during pregnancy consisted on azathioprine, prednisolone and hydroxychloroquine. SLE Flares occurred in 7/26 (27%) patients, with minor relapses in 4/6 gestations (hepatic, skin and articular involvement) and major renal flares in 3/6 gestations. All renal relapses occurred in patients with no preconception counseling nor immunosuppressive therapy. PE occurred in 2/26 (7,6%) gestations. Abortion occurred in 6/26 pregnancies (3 spontaneous abortions, 2MTP, 1 voluntary interruption). Cesarean (C) rate was 34,6%. Mean gestation age at delivery was 37±3 (28-40) weeks. Mean birth weight was 2789±859 mg (800-4175), 4 newborns were low birth weight (<2500 g). Apgar scores at 5/10 minutes were 10/10, respectively. Neonatal intensive care (NICU) was needed in 5 newborns. Conclusion In our series of SLE patients with LN, worsening kidney function only occurred in patients with advanced CDK, and renal flares in patients without preconceptional counseling nor immunosuppressive therapy, which underlines the importance of careful pregnancy planning. One patient with proliferative LN was successfully treated with tacrolimus associated to azathioprine and prednisolone during pregnancy, being a valuable therapeutic option in these situations. Although SLE patients with LN can have safe pregnancies, we still found an increased incidence of maternal, obstetric and perinatal complications, namely HTN, PE, C, low birth weight and the need of NICU.

#1864 Phosphorilation of SHP-1 switch does not indicate lupus nephritis activity

Abstract Background and Aims Protein tyrosine kinases (PTKs) are enzymes responsible for the phosphorylation of tyrosine residues in lymphocytes. In 2017, Mkaddem et al. suggested that unique PTK signatures in peripheral leukocytes (PBMC) are associated with lupus nephritis (LN) activity [1]. Lymphocytes express two important PTKs, Lyn and Fyn, that modulate inhibitory or activatory signals depending on ligand avidity or phosphorylation status. SHP-1 tyrosine 536 phosphorylation (pSHP1-Y536) by Lyn activates inhibitory signaling and Fyn-dependent phosphorylation of SHP-1 serine 591 (pSHP1-S591) inactivates the phosphatase, enabling activatory immunoreceptor signaling. We hypothesized that active and refractory patients with proliferative LN have a different PTK profile in PBMC, with lower expression of pSHP1-Y536 and greater expression of pSHP1-S591, in comparison with those who have responded to treatment. Method In a cohort from the Royal Free Hospital, UCL (London, UK) we performed western blotting of PBMC lysates for SHP1-phospho-S591 and-Y536 from healthy individuals (HC; n = 19), LN patients in remission (n = 11) and with ongoing disease activity (n = 4). Densitometry of bands was carried out and a ratio of S591:Y536 expression was calculated (both normalized to actin). For the flow cytometry analysis, we followed up a Brazilian cohort of LN (n = 24) from Hospital das Clinicas, UFPE (Recife, Brazil). All patients had ongoing active LN with initial renal biopsy (class III, IV or/and V). PBMC samples were collected at 0, 3, 6, 9, 12, 18, and 24 months after biopsy. Isolated PBMC samples were stored at −80°C. PBMC samples were stained with antibodies against pSHP1 S591 and p-SHP1 Y536 and cell viability was checked using zombie red dye. Samples were acquired on the Accuri C6 cytometer (BD) and analyzed using the FLOJO software (BD). Results The western blotting relative expression of pSHP-1 S591:Y536 in PBMC was not significantly different when we compared HC with active LN (p = 0.098) and active with remission LN (p = 0.10), Fig. 1. The results obtained by flow cytometry expression ratio of pSHP1-S591:Y536 did not show a significant correlation with the median of proteinuria (Fig. 2), C3, C4, or SLEDAI from time of active kidney biopsy during LN flare throughout induction treatment. Conclusion There was no expression pattern of pSHP-1 Y536 and S591 in PBMC of LN patients, regardless of their renal activity or inflammatory status. Therefore, we cannot state those markers as a potential “liquid biopsy” for LN.

#1707 Antiphospholipid antibodies in lupus nephritis

Abstract Background and Aims Antiphospholipid antibodies (aPL) constitute a heterogeneous family of antibodies against anionic phospholipids or phospholipid-binding proteins. They may occur in association with autoimmune diseases, infections, and sometimes in the general population. Lupus nephritis (LN) is a major manifestation of systemic lupus erythematosus (SLE). The aim of this study was to investigate the association of aPL with clinical activity, renal damage, renal activity and outcomes in patients with LN. Method A total of 157 patients (11 male, 146 female, age between 17 and 58 years) with LN were included in this study. The International Society of Nephrology/Renal Pathology Society (ISN/RPS) 2003 classification of LN was used to classify the patients into LN subsets. Histopathological renal activity and damage were estimated using the Activity Index (AI) and Chronicity Index (CI), respectively. Levels of anticardiolipin (aCL) antibodies, anti-β2-glycoprotein I (anti-β2-GPI) antibodies and lupus anticoagulant (LAC) were measured, and other clinical and pathological data were also obtained. Long-term renal outcome was determined by the estimated glomerular filtration rate (eGFR) and the Chronic Kidney Disease stage, after a median follow-up of 20,5 ± 8, 7 years, counting from the occasion of the first renal biopsy. Renal and extra-renal symptoms were analyzed. Patients which have more than one class LN features, were excluded from the study. The treatment includes standard treatment for LN, inhibitors of the angiotensin system in patients with hypertension and proteinuria, steroids, anticoagulants, cyclophosphamide, mycophenolate mofetil, azathioprine. Results LN patients were classified according to the baseline renal biopsies as patients with: minimal mesangial LN (4), mesangial-proliferative LN (30), focal proliferative LN (31), diffuse proliferative LN (48), membranous LN (44). aPL antibodies were detected in 89 (56,69%) patients, aCL antibodies – in 72 (45,86%), anti-β2-GPI antibodies – in 58 (36,94%) and LAC were detected in 46 (29,30%) patients. None of these patients had a concomitant diagnosis of antiphospholipid syndrome nephropathy. Follow-up was similar between aPL-positive and aPL-negative patients. LN patients with positive aPL antibodies had significantly higher SLEDAI (p < 0,05), anti-dsDNA levels (p < 0,05), anti-ribosomal-P antibodies levels (p < 0,05), anti-C1q antibodies (p < 0,05), lower serum C3 (p < 0,005) and C4 (p < 0,05) levels, and higher intensity of complement C3 (p < 0,05) deposits in kidney tissue than the aCL antibody–negative LN patients. aPL-seropositivity was associated with more rapid decline in eGFR (–1,06 mL/min/year compared to –0,45 mL/min/year in aPL-seronegative patients) and showed inferior patient survival (89,8% and 67,9% at 10 and 15 years, respectively, compared to 97,3% and 76% in aPL-seronegative patients). No significant correlation was found between serum aPL antibodies levels and activity or chronicity index scores in renal biopsies at baseline, ANA levels, or age. Conclusion We concluded that aPL-seropositivity are correlated with clinical activity in patients with LN and are associated with inferior long-term patient survival.

#1803 Is class II lupus nephritis as benign as one thinks?

Abstract Background and Aims The classification of Lupus Nephritis (LN) plays a pivotal role in determining prognosis and guiding treatment, aligning with ISN/RPS recommendations. KDIGO and EULAR advocate for immunosuppression in cases of proliferative LN (Class III/IV) and Class V with nephrotic syndrome, while “non-proliferative” instances (Class I and II) are advised conservative care. In a contrasting approach, GLOSEN recommends immunosuppression for Class II if persistent proteinuria exceeds 1g. ISN/RPS suggests incorporating activity and chronicity indexes to further refine the classification of LN. Concerns surrounding immunosuppression in LN Class II arise from its favorable long-term kidney survival and potential drug toxicity. However, the need for caution is underscored by a 30–50% class transformation rate. Limited research comparing the long-term prognosis of treated and untreated patients exists due to the gradual progression of the disease. The use of Activity (NIH-A) and Chronicity (NIH-C) indexes, particularly in the context of protocol biopsies, offers an opportunity to reassess the perceived benign nature of LN Class II. Method In this single-center investigation, patients diagnosed with LN belonging to Class II or II+V from 1999 to 2021 were examined. Biopsies were classified according to ISN/RPS criteria and evaluated using the NIH-A and NIH-C Indexes. Patients previously diagnosed with Class III/IV LN and those experiencing class transformation to a proliferative class were excluded. We present the findings in a descriptive manner. Results Sixteen patients, with a median age of 38.5 (12 female), were included. Histological findings from the initial biopsies revealed a NIH-A of 0, with NIH-C exceeding 0 in 31% (5/16) cases. Six patients exhibited Class II plus V, with varying NIH-C scores. The primary contributors to NIH-C in the initial biopsies were tubular atrophy and interstitial fibrosis. Ten patients underwent a second biopsy after an average time lapse of 39 months (7-101). The decision for most second biopsies was based on clinical judgment rather than a standardized protocol. One patient initially diagnosed with Class II+V displayed Class II on the second biopsy, and vice versa. In 70% of patients the NIH-C increased, primarily driven by glomerulosclerosis. The rise in NIH-C scores was observed in 3/6 patients with Class II+V and in all 4 patients with isolated Class II. Most patients received mycophenolate, and 3 were treated with low-dose prednisolone. The clinical and histologic characteristics of the 10 patients who underwent a second biopsy are outlined in Tables 1 and 2. Conclusion Our limited, biased study raises questions rather than providing definitive evidence. The consistent NIH-C rise challenges Class II LN perceived benign nature. It is plausible that not all LN Class II cases are equivalent and histological variances, such as mesangial proliferation, or its focal or diffuse distribution impact outcomes. Histological variations and treatment impact on LN Class II warrant further investigation.

OA25 Transcriptome analysis of peripheral blood and renal tissue identifies genes that predict treatment response in proliferative lupus nephritis: a prospective observational study

Abstract Background/Aims Mechanisms contributing to non-response in lupus nephritis (LN) are not clear. Peripheral blood mononuclear cells (PBMCs) serve as easily available less invasive alternative to kidney biopsy in monitoring treatment response. However, it is unclear to what extent peripheral blood mirrors the inflamed kidney. This study aims to identify changes in functional pathways from PBMCs and renal tissues after cyclophosphamide treatment and to identify baseline genes that predict treatment response by RNA-sequencing. Methods RNA from PBMCs and renal biopsies was extracted from 16 treatment-naïve proliferative LN at baseline, 6-months and at the time of flare within 2 years of follow-up. Patients were classified as clinical-responders (CR) (n = 4) or non-responders (NR) (n = 8) at 6-months using EULAR/EDTA criteria. CR who developed renal flare on follow-up were considered FL (n = 4). RNA was sequenced on Illumina Novaseq-6000 platform. Healthy control datasets were taken from public databases. Differentially expressed genes (DEGs) and enriched pathways were analysed using Reactome database-v74. Comparisons for each group were performed before vs after treatment. Weighted gene co-expression network analysis (WGCNA) was used to identify baseline hub genes that predict treatment-response and ROC analysis was used to test their prognostic utility. Results Functional enrichment analysis identified neutrophil degranulation, autophagy, regulation of NF-κβ signalling, FCGR-dependent phagocytosis and TNF signalling upregulated and IFN-γ signalling and ECM molecules downregulated in PBMCs of CR. ECM molecules and proteoglycans, neddylation and BCR signalling were enriched in PBMCs of NR. In NR renal tissue, apoptosis, NF-κβ signalling, IKK complex formation upon TLR signalling and MAPK signalling were enriched. In FL PBMCs, neutrophil degranulation, ROS and RNS production in phagocytes, antimicrobial peptide and immune system pathways were downregulated. In FL renal tissue, glycogen metabolism, viral mRNA translation, cell-ECM interactions, cell-cell communications, apoptosis and ISG15 antiviral mechanism were downregulated. Clinical traits for WGCNA were BCR, BNR, BFL and HC. The most correlated modules and hub genes from baseline PBMC were: green (BCR- IFI27, CD24, AZU1, MT2A, SNRNP70), brown (BNR- AC090809.1, TENM2, NLGN1, LSAMP, DLGAP2, AP005230.1, TMEM132D, AL445255.1, LINC00536, AC013287.1, BX470102.1, TM4SF20) and blue module (BFL- AC092436.3, AC046158.3, LINC01147). From baseline renal tissues, the most correlated modules and genes were: green (BCR- AP003068.1, BX470102.1, AC009088.3, AC136475.1, AC073611.1, AP000757.2) and turquoise module (BNR & BFL: TRDN-AS1, AC107973.1, AL672167.1, AC020637.1, AL137100.3, AC018437.3, LINC01982, TPH2, AC136759). From PBMCs, ROC analysis showed that combinational model of TENM2, NLGN1 and AP005230.1 predicted NR (AUC-0.94; 95% CI: 0.80-1; p = 0.02) and AC092436.3 predicted FL (AUC-0.81; 95% CI: 0.53-1; p = 0.036). AP005230.1 from renal tissue also predicted NR (AUC-0.94; 95% CI: 0.82-1; p = 0.01). Conclusion Type I IFN and fibrosis pathways were enriched in NR and downregulated in CR and FL. Baseline PBMC markers TENM2, NLGN1 & AP005230.1 predicted NR and FL. AP005230.1 from PBMCs & renal tissue predicted NR. Disclosure S. Bulusu: None. A. Bavikatte: None. S. Shah: None. S. Murthy: None. C.M. Mariaselvam: None. C. Kavadichanda: None. S. Vembar: None. M. Thabah: None. V.S. Negi: None.

Risk of chronic kidney disease in 260 patients with lupus nephritis-analysis of a nationwide multicentre cohort with up to 35 years of follow-up.

To compare proliferative (PLN) and membranous (MLN) lupus nephritis (LN) regarding clinical and laboratory presentation and long-term outcomes; To investigate predictors of progression to chronic kidney disease (CKD). Multicentre observational study, with retrospective analysis of a prospective cohort, using data from the Rheumatic Diseases Portuguese Registry-Reuma.pt. Patients with biopsy-proven PLN, MLN and mixed LN were included. Cox regression survival analysis was used to investigate predictors of CKD. 260 patients were included. Median follow-up was 8 years (IQR 11; minimum 1, maximum 35 years). MLN patients presented with significantly lower serum creatinine (0.70 (IQR 0.20; minimum 0.50, maximum 1.30) mg/dl vs 0.80 (IQR 0.31; minimum 0.26, maximum 2.60) in PLN, p= 0.003). Proteinuria levels did not differ between groups (p= 0.641). Levels of complement were reduced in PLN but nearly normal in MLN patients, and there were fewer patients with positive anti-dsDNA antibodies in the MLN group (p< 0.001). One year after the beginning of treatment, 62% of the patients achieved EULAR/ERA-EDTA complete response, with further 5% achieving partial response. Patients with lower proteinuria at diagnosis were more likely to achieve a complete renal response at one year, however, proteinuria at diagnosis or at one year did not predict long term CKD. Estimated glomerular filtration rate (eGFR) ≤75 mL/min/1.73 m2 at one year was the strongest predictor of progression to CKD (HR 23 [95% CI 8-62], p< 0.001). Other possible predictors included the use of azathioprine for induction of remission, older age at diagnosis and male sex. Proteinuria levels did not predict LN histologic class in our cohort. eGFR cutoff of 75 mL/min/1.73 m2 after one year of treatment was strongly predictive of progression to CKD.

Maternal and fetal outcomes in pregnancy complicated by pre-existing lupus nephritis: Insights from a developing country Pakistan.

Pregnancy in women with systemic lupus erythematosus (SLE) has remained a great challenge for clinicians in terms of maternal and fetal outcomes. The outcomes in women with pre-existing lupus nephritis (LN) are variable. The impact of different classes of LN on maternal and fetal outcomes during pregnancy is not well defined, as data is very scarce, especially from the developing countries. A retrospective analysis was conducted on 52 women with 89 pregnancies. All had biopsy-proven LN. Those women who conceived at least 6months after the diagnosis were included. The analysis was conducted between July 1998 and June 2018 at Sindh Institute of Urology and Transplantation (SIUT), evaluating the outcomes for both the mother and the fetus with a minimum follow-up of 12months after child birth. The mean maternal age at SLE diagnosis was 21.45 ± 6years and at first pregnancy was 26.49 ± 5.63years. The mean disease duration was 14.02 ± 19.8months. At conception, 47 (52.8%) women were hypertensive, 9 (10%) had active disease while 38 (42.7%) and 42 (47.2%) were in complete and partial remission, respectively. A total of 17 (19.1%) were on mycophenolate mofetil (MMF), which was switched to azathioprine (AZA). Out of 89 pregnancies, 56 (62.9%) were successful, while 33 (37.07%) had fetal complications like spontaneous abortion, stillbirth, perinatal death, and intrauterine growth retardation (IUGR). There were more vaginal deliveries (33 [58.92%]) than caesarean sections (23 [41.07%]). Renal flare was observed in 33 (37.1%) women while 15 (16.9%) developed pre-eclampsia. Proliferative LN was found in 56 (62.9%) cases, but no significant differences were found in maternal and fetal outcomes in relation to LN classes (p = .58). However, disease outcomes at 12months were significantly poor in those with active disease at the time of conception (p < .05). There was only one maternal death. A total of 10 (11.2%) women showed deterioration in renal function and 5 (5.6%) were dialysis-dependent at 12months. The maternal and fetal outcomes in pre-existing LN depend on the disease activity at the time of conception. No correlation was found between International Society of Nephrology/Renal Pathology Society (ISN/RPS) classes of LN and adverse disease and pregnancy outcomes.

IKZF1 rs4132601 and rs11978267 gene polymorphisms and paediatric systemic lupus erythematosus; relation to lupus nephritis.

The demographic factors, the socioeconomic status and the ethnicity of populations are important players that determine the incidence, the prevalence and the spectrum of systemic lupus erythematosus (SLE) clinical presentations in different populations. Therefore, the purpose of the present research was to investigate the possible association between the Ikaros family zinc finger 1 gene (IKZF1) rs4132601 and rs11978267 single nucleotide polymorphisms (SNPs) and SLE susceptibility and clinical presentations including lupus nephritis (LN) among Egyptian paediatric patients. After DNA extraction from Ethylenediaminetetraacetic acid (EDTA) blood samples for 104 paediatric SLE (pSLE) patients and 286 healthy controls, the investigated SNPs (IKZF1 rs4132601 and rs11978267) were genotyped using TaqMan-Real-time Polymerase chain reaction (PCR). The G allele, GG and GT genotypes of IKZF1 rs4132601 were associated with pSLE (pc<.001, OR 2.97, 3.2 and 2.25, respectively). The GG and GA haplotype were more frequent in pSLE patients than other haplotypes (pc<.001, OR 3.47 and pc=.004, OR=2.8, respectively). The studied SNPs have no impact on the distinctive features of pSLE. The rs4132601 TG genotype was significantly associated with proliferative LN (pc=.03) The IKZF1 rs4132601 can be considered a risk factor for SLE in the cohort of Egyptian children. The TG genotype of the IKZF1 rs4132601 may predispose to proliferative LN.

Renal Manifestation of Mixed Connective Tissue Disease

Abstract A young female presented with facial puffiness and swelling in both lower limbs for 3 months, distension of the abdomen, and breathlessness on exertion for 1 month with a history of hypertension and hypothyroid on regular treatment. On general physical examination, there were pallor, bilateral pitting edema, tachycardia, and blood pressure of 190/100 mmHg. Abdominal examination revealed shifting dullness. Respiratory and cardiovascular systems were normal. Fundoscopy revealed Grade 1 papilledema, and the rest of the neurological examination was unremarkable. Investigations showed normocytic normochromic anemia, serum creatinine of 1.6 mg/dl, and hypoalbuminemia; urine R/E showed significant proteinuria; and anti-U1 ribonucleoprotein particle antibodies were positive. Two-dimensional echocardiography showed mild concentric left ventricular hypertrophy and mild pericardial effusion. Ultrasonography abdomen showed bilateral renal parenchymal disease and moderate ascites. Renal biopsy revealed diffuse proliferative glomerulonephritis and lupus nephritis Class IV. Renal manifestation is very rare in mixed connective tissue disease as an initial presentation

Lupus nephritis – modern aspects of diagnosis and therapy. Part I

Lupus nephritis (LN) is considered to be one of the most frequent severe manifestations of systemic lupus erythematosus (SLE), its various colonic manifestations occur in at least 50% of SLE patients, both at the onset and at various stages of the disease, and develop LN is considered one of the most important predictors of mortality in SLE. The structure of nephritis is dominated by diffuse proliferative LN with clinical and morphological signs of progression and the rapid development of terminal renal failure. SLE is diagnosed based on the 2019 EULAR/ACR (European Alliance of Associations for Rheumatology/American College of Rheumatology) diagnostic classification criteria. To confirm the diagnosis, evaluate the prognosis, and choose the tactics of treating the dis-ease, all patients in the absence of contraindications require a kidney biopsy. In addition to LN, the spectrum of SLE-associated renal lesions includes vascular pathology represented by thrombotic microangiopathy, lupus vasculopathy or vasculitis, tubulointerstitial injury, and lupus podocytopathy.

Potential involvement of circulating exosomal miRNA-146a in disease activity and TRAF6 gene expression in juvenile proliferative lupus nephritis

BackgroundJuvenile SLE (JSLE) is a complex autoimmune disorder that predominantly affects children and adolescents with several unique challenges, and microRNA-146a (miRNA-146a) might be an interesting anti-inflammatory molecule. Because exosomes in...

Clinico-serological associations of urinary activated leukocyte cell adhesion molecule in systemic lupus erythematosus and lupus nephritis

BackgroundLupus nephritis (LN) is one of the major complications associated with Systemic Lupus Erythematosus (SLE). Activated leukocyte cell adhesion molecule (ALCAM or CD166) is a promising urine biomarker that binds to CD6, a receptor found on lymphocytes. This binding results in T-cell activation, proliferation, and recruitment, which causes tissue inflammation and may explain the pathophysiology of LN.Aim of workInvestigate the urinary ALCAM level in SLE, study its relationship to disease activity, and clarify the association with LN activity and histopathology.Patients and methodsA case–control study was performed on 60 patients with SLE and 20 matched controls. The SLE disease activity index (SLEDAI) and the activity of renal disease (rSLEDAI) were evaluated. Renal biopsy and uALCAM levels were also investigated.ResultsUrinary ALCAM levels were higher significantly in active LN patients than inactive LN patients, active and inactive non-LN SLE, and the control group (p < 0.001). The cut-off value for identifying active and inactive LN was above 270 ng/mg (p < 0.001). ALCAM levels were greater in proliferative (class III, IV, and IV/V) than in non-proliferative (class II and V) LN (p < 0.001). ALCAM exhibited high positive correlations with SLEDAI and rSLEDAI (p < 0.001 each) and negative significant correlations with C3 (p < 0.001) and C4 (p = 0.005).ConclusionUrinary ALCAM is a sensitive biomarker evaluating LN in SLE patients. Levels above 270 ng/mg can help distinguish between active and inactive LN. ALCAM levels are correlated positively with SLEDAI and rSLEDAI but have a negative correlation with C3 and C4.Key Points• Urinary ALCAM shows promise as a biomarker for evaluating kidney dysfunction in SLE patients.• It is a non-invasive marker that can differentiate between proliferative and non-proliferative LN.• A urinary ALCAM level above 270 ng/mg can indicate active LN, while lower levels indicate inactive LN.• Urinary ALCAM levels are correlated positively with SLEDAI and rSLEDAI scores but correlated negatively with C3 and C4.

Urine proteomic signatures of histological class, activity, chronicity, and treatment response in lupus nephritis.

Lupus nephritis (LN) is a pathologically heterogenous autoimmune disease linked to end-stage kidney disease and mortality. Better therapeutic strategies are needed as only 30%-40% of patients completely respond to treatment. Noninvasive biomarkers of intrarenal inflammation may guide more precise approaches. Because urine collects the byproducts of kidney inflammation, we studied the urine proteomic profiles of 225 patients with LN (573 samples) in the longitudinal Accelerating Medicines Partnership in RA/SLE cohort. Urinary biomarkers of monocyte/neutrophil degranulation (i.e., PR3, S100A8, azurocidin, catalase, cathepsins, MMP8), macrophage activation (i.e., CD163, CD206, galectin-1), wound healing/matrix degradation (i.e., nidogen-1, decorin), and IL-16 characterized the aggressive proliferative LN classes and significantly correlated with histological activity. A decline of these biomarkers after 3 months of treatment predicted the 1-year response more robustly than proteinuria, the standard of care (AUC: CD206 0.91, EGFR 0.9, CD163 0.89, proteinuria 0.8). Candidate biomarkers were validated and provide potentially treatable targets. We propose these biomarkers of intrarenal immunological activity as noninvasive tools to diagnose LN and guide treatment and as surrogate endpoints for clinical trials. These findings provide insights into the processes involved in LN activity. This data set is a public resource to generate and test hypotheses and validate biomarkers.

Clinical profiles in pediatric systemic lupus erythematosus: a retrospective study

Aims: This study aimed to analyse clinical and laboratory findings, prognosis, and survival of systemic lupus erythematosus (SLE) patients, differentiating according to gender, pubertal status, and renal involvement. Methods: Ninety-six pediatric SLE patients, diagnosed using ACR criteria, were retrospectively analyzed. Inclusion criteria comprised age under 18, meeting at least four ACR criteria, and six months of monitoring. Data encompassed demographics, symptoms, diagnosis, organ involvement, autoantibodies, treatment, prognosis, and survival. Categorization was based on gender and pubertal status. Renal biopsies followed WHO-ISN classification, with asymptomatic findings termed “silent lupus nephritis.” Biopsied patients were divided into proliferative and non-proliferative lupus nephritis categories, excluding irreversible damage cases. Outcomes studied included remission, relapse, end-stage renal failure, and mortality. Results: Among 96 participants, females constituted 82.3%, males 17.7%, resulting in a female-to-male ratio of 4.6:1. Mean age at diagnosis was 11.9 years, with 37 prepubertal (38.5%) and 59 pubertal (61.5%) cases. Oral-nasal ulcers (p=0.01) were more prevalent in males related to system involvement. Nephrotic syndrome prevalence increased from 21.6% in prepubertal to 44.1% in pubertal cases (p=0.025). Positive Anticardiolipin IgM antibodies decreased from 56.2% in prepubertal to 25.9% in pubertal cases (p=0.047). Type IV lupus nephritis was predominant, followed by Type II, in prepubertal and pubertal groups and both genders. Proliferative lupus nephritis showed higher rates of renal involvement (95.7% vs. 65.6%), nephrotic syndrome (46.8% vs. 21.9%), proteinuria (89.4% vs. 62.5%), hematuria (57.4% vs. 28.1%), elevated creatinine (43.5% vs. 9.7%), and low albumin (67.4% vs. 23.3%). Cases with proliferative lupus nephritis had higher neuropsychiatric involvement (36.2% vs. 12.5%), seizures (25.5% vs. 3.1%, p=0.008), and increased hemolytic anemia rates (78.7% vs. 56.2%, p=0.033). Thirteen had silent lupus nephritis, revealing various types through biopsy. All reported deaths occurred within the first five years, resulting in stable 91% survival rates at 5, 10, and 15 years. Conclusion: This study provides insights into the clinical, prognostic, and survival characteristics of pediatric systemic lupus erythematosus (SLE), revealing notable patterns related to gender, pubertal development, and renal involvement. There is an association between proliferative lupus nephritis and renal involvement, nephrotic syndrome, and neuropsychiatric symptoms. Significantly, silent lupus nephritis highlights the complex renal implications, necessitating diligent surveillance for prompt intervention.

Renal Response Outcomes of the EuroLupus and National Institutes of Health Cyclophosphamide Dosing Regimens in Childhood-Onset Proliferative Lupus Nephritis.

We compared clinical characteristics and renal response in patients with childhood-onset proliferative lupus nephritis (LN) treated with the EuroLupus versus National Institutes of Health (NIH) cyclophosphamide (CYC) regimen. A retrospective cohort study was conducted at 11 pediatric centers in North America that reported using both CYC regimens. Data were extracted from the electronic medical record at baseline and 3, 6, and 12 months after treatment initiation with CYC. To evaluate the adjusted association between CYC regimen (EuroLupus vs NIH) and renal response over time, generalized estimating equations with a logit link were used. An interaction between time and CYC regimen was included, and a contrast between CYC regimens at 12 months was used to evaluate the primary outcome. One hundred forty-five patients (58 EuroLupus, 87 NIH) were included. EuroLupus patients were on average older at the start of current CYC therapy, had longer disease duration, and more commonly had relapsed or refractory LN compared with the NIH group. After multivariable adjustment, there was no significant association between CYC regimen and achieving complete renal response at 12 months (odds ratio [OR] of response for the EuroLupus regimen, reference NIH regimen: 0.76; 95% confidence interval [CI] 0.29-1.98). There was also no significant association between CYC regimen and achieving at least a partial renal response at 12 months (OR 1.35, 95% CI 0.57-3.19). Our study failed to demonstrate a benefit of the NIH regimen over the EuroLupus CYC regimen in childhood-onset proliferative LN. However, future prospective outcome studies are needed.