Urinary HER2, TWEAK and VCAM-1 levels are associated with new-onset proteinuria in paediatric lupus nephritis.

OBJECTIVE: Lupus nephritis is a key driver of morbidity and mortality in SLE. Detecting active nephritis on a background of pre-existing renal damage is difficult, leading to potential undertreatment and accumulating injury. An unmet need is a biomarker that distinguishes active lupus nephritis, particularly important in paediatrics where minimising invasive procedures is desirable. METHODS: This was a multicentre, prospective study of 113 paediatric patients with biopsy-proven lupus nephritis. Clinical data and urine were obtained every 3-4 months and patients averaged 2 years on study with seven time points. Urine was analysed for human epidermal growth factor receptor 2 (HER2), tumour necrosis factor-like weak inducer of apoptosis and vascular cell adhesion molecule-1 (VCAM-1) by ELISA. We defined active disease as either a rise in serum creatinine ≥0.3 mg/dL from baseline or a rise in renal Systemic Lupus Erythematosus Disease Activity Index score from the previous visit. These markers were also studied in patients with acute kidney injury, juvenile idiopathic arthritis (JIA), amplified pain syndrome and healthy controls. RESULTS: The rate of active disease was 56% over an average of 2 years of follow-up. HER2 and VCAM-1 were significantly elevated at time points with active disease defined by increased serum creatinine compared with time points with inactive disease or patients who never flared. All three biomarkers were associated with new-onset proteinuria and VCAM-1 was elevated at time points preceding new-onset proteinuria. These biomarkers were not increased in acute kidney injury or JIA. CONCLUSION: All three biomarkers were associated with new onset proteinuria and increased VCAM-1 may predict impending proteinuria. These biomarkers provide potential non-invasive measures for monitoring that may be more sensitive to impending flare than conventional measures.

Prognostic and Diagnostic Values of Novel Serum and Urine Biomarkers in Lupus Nephritis: A Systematic Review.

INTRODUCTION: While renal biopsy remains the gold standard for diagnosing lupus nephritis (LN), the prognostic and diagnostic role of non-invasive biomarkers for LN is currently debated. METHODS: Available studies published in last 5 years (2015-2020) assessing the diagnostic and prognostic value of urinary and/or serological biomarkers in subjects with LN were analyzed in this systematic review. RESULTS: Eighty-five studies were included (comprehending 13,496 patients with systemic lupus erythematosus [SLE], 8,872 LN, 487 pediatric LN, 3,977 SLE but no LN, 160 pediatric SLE but no LN and 7,679 controls). Most of the studies were cross-sectional (62; 73%), while 14 (17%) were prospective. In sixty studies (71%), the diagnosis of LN was biopsy-confirmed. Forty-four out of 85 (52%) investigated only serological biomarkers, 29 studies (34%) tested their population only with urinary biomarkers, and 12 (14%) investigated the presence of both. Outcome measures to assess the clinical utility of the analyzed biomarkers were heterogeneous, including up to 21 different activity scores, with the SLEDAI (in 60%) being the most used. Despite some heterogeneity, promising results have been shown for biomarkers such as urinary monocyte chemoattractant protein, urinary adiponectin, and urinary vascular cell adhesion protein 1. DISCUSSION/CONCLUSION: While serum and urine biomarkers have the potential to improve diagnostic and prognostic pathways in patients with LN, the vast heterogeneity across studies severely limits their applicability in current clinical practice. With the kidney biopsy still representing the gold standard, future efforts should focus on harmonizing study inclusion criteria and outcomes, particularly in clinical trials, in order to improve comparability and facilitate the implementations of available biomarkers into the daily practice.

Urinary Tumor Necrosis Factor-Like Weak Inducer of Apoptosis (uTWEAK) and Urinary Monocyte Chemo-attractant Protein-1 (uMCP-1): Promising Biomarkers of Lupus Nephritis Activity?

There is no single biomarker to detect lupus nephritis (LN) activity. Renal biopsy is still the gold standard method but it is invasive and mainly used in the initial assessment of the patients. Urinary tumor necrosis factor-like weak inducer of apoptosis (uTWEAK) and urinary monocyte chemo-attractant protein-1 (uMCP-1) can be secreted in the urine of active LN. The aim of the study is to assess the potential role of uTWEAK and uMCP-1 in lupus patients and to determine their correlation with disease activity. This is a case-control study conducted on a total of 114 subjects; 92 systemic lupus erythematosus (SLE) patients and 22 healthy volunteers. The patients were recruited from the rheumatology unit at the internal medicine department, Tanta University Hospital, Tanta, Egypt. The patients and controls were subjected to full history taking, complete clinical examination, routine laboratory tests, uTWEAK and uMCP-1 measurement, assessment of the disease activity using SLE Disease Activity Index (SLEDAI), and renal SLEDAI (rSLEDAI) scores. uTWEAK and uMCP-1 levels were higher in SLE with active nephritis group than those of other SLE groups and controls. There was a significant positive correlation between uTWEAK and uMCP-1 levels in lupus patients with proteinuria, anti-dsDNA, SLEDAI and r-SLEDAI and a negative correlation with C3 and C4. TWEAK showed a sensitivity of 80.43% and 100% and specificity of 50% and 100% in detecting lupus activity and LN activity, respectively. Furthermore, uMCP-1 showed a sensitivity of 82.6% and 100% and specificity of 50% and 100% in detecting lupus activity and LN activity, respectively. uTWEAK and uMCP-1 are new, easily obtained, accurate markers with high sensitivity and specificity in the detection of LN activity.

Urinary MCP-1 and TWEAK as non-invasive markers of disease activity and treatment response in patients with lupus nephritis in South Africa.

BACKGROUND: Treatment of patients with lupus nephritis (LN) requires judicious use of immunosuppression. Novel biomarkers may be useful for monitoring disease activity and treatment response. We assessed the utility of urinary monocyte chemoattractant protein-1 (uMCP-1) and urinary tumour necrosis factor-like weak inducer of apoptosis (uTWEAK) for disease activity and treatment response monitoring in South Africans with LN. METHODS: We recruited consenting patients with active LN confirmed on kidney biopsy. Urinary levels of MCP-1 and TWEAK were assayed at baseline and after completion of induction therapy using ELISA methods. We also collected relevant demographic, clinical and biochemical data for patients included in this study. RESULTS: The mean age of patients in this study was 29.8 ± 10.7 years, 60% were patients of mixed ancestry, 70% had proliferative LN and mean spot urine proteinuria at baseline was 0.37 (0.18-0.59) g/mmolCr. At completion of induction therapy, the level of uMCP-1 had reduced to 314.5 (IQR: 197.0-622) pg/mgCr from a baseline of 1092.7 (IQR 578.6-1848) pg/mgCr (P = 0.06) while uTWEAK had reduced to 36.0 (IQR 17.0-88.0) pg/mgCr from 159.0 (IQR: 88.5-295.5) pg/mgCr (P = 0.03). For patients reaching early complete or partial remission (n = 17), both biomarkers had significantly declined in their urine: uMCP-1 (P = 0.018) and uTWEAK (P = 0.015). There was no reduction of both biomarkers in patients not achieving remission and no association between uMCP-1 or uTWEAK with renal histological features. CONCLUSION: Our study shows that uMCP-1 and uTWEAK are elevated in patients with active LN, correlated with the remission status (response to treatment) at the end of induction therapy and can, therefore, be useful for monitoring disease activity and treatment response.

Serum and urine TNF-like weak inducer of apoptosis, monocyte chemoattractant protein-1 and neutrophil gelatinase-associated lipocalin as biomarkers of disease activity in patients with systemic lupus erythematosus.

OBJECTIVES: TNF-like weak inducer of apoptosis (TWEAK), monocyte chemoattractant protein-1 (MCP-1) and neutrophil gelatinase-associated lipocalin (NGAL) are proinflammatory cytokines/chemokines that are considered as potential biomarkers reflecting disease activity in systemic lupus erythematosus (SLE). In this study, we aimed to investigate the association of serum (s) and urine (u) levels of TWEAK, MCP-1 and NGAL with disease activity in both renal and extra-renal SLE. METHODS: Thirty active patients with SLE (15 renal and 15 extra-renal) were recruited. Thirty-one inactive patients with SLE (16 renal and 15 extra-renal), 14 patients with ANCA-associated vasculitis (AAV) all of whom had active renal involvement and 20 healthy volunteers were selected as control groups. Serum and urine levels of TWEAK, MCP-1 and NGAL were tested using ELISA. RESULTS: Serum and urine levels of TWEAK and NGAL were significantly higher in the active SLE group compared to the inactive SLE group (sTWEAK p = 0.005; uTWEAK p = 0.026; sNGAL p < 0.001; uNGAL p = 0.002), whilst no significant differences regarding serum and urine MCP-1 levels were observed (p = 0.189 and p = 0.106, respectively). uTWEAK (p = 0.237), sMCP-1 (p = 0.141), uMCP-1 (p = 0.206), sNGAL (p = 0.419) and uNGAL (p = 0.443) levels did not differ between patients with active renal and extra-renal SLE. Serum TWEAK was higher in patients with active renal SLE (p = 0.006). There were no differences between active renal SLE and active renal AAV. Levels of all biomarkers were correlated with the SLE Disease Activity Index. CONCLUSION: sTWEAK, uTWEAK, sNGAL and uNGAL are biomarkers showing disease activity in SLE. However, our results implicate that these biomarkers may not be specific for SLE, and can be elevated in patients with active renal involvement of AAV.

Clinical significance of urinary tumor necrosis factor-like weak inducer of apoptosis (TWEAK) in immunoglobulin A nephropathy
.

AIMS: Tumor necrosis factor-like weak inducer of apoptosis (TWEAK) has been implicated as a mediator of chronic inflammatory processes. Recently, it was reported that TWEAK may play an important role in the pathogenesis of kidney damage. In the present study, we investigated the role of TWEAK in immunoglobulin A nephropathy (IgAN). MATERIALS AND METHODS: The levels of serum TWEAK (sTWEAK) and urinary TWEAK (uTWEAK) in 45 patients with IgAN and 15 healthy subjects were measured. We analyzed the correlations of uTWEAK level with clinical and pathological parameters in patients with IgAN. We then divided the patients into two groups according to uTWEAK level and investigated 5-year chronic kidney disease (CKD) progression. RESULTS: The level of uTWEAK was significantly higher in patients with IgAN than in healthy controls (p < 0.001). sTWEAK level showed no significant difference between the two groups (p = 0.225). The level of uTWEAK correlated significantly with serum albumin (p < 0.001), urine protein excretion (p < 0.001), and histological classification (p < 0.016) in patients with IgAN. uTWEAK was significantly increased even in patients with IgAN who had lower proteinuria. There was a significant association between uTWEAK level and CKD progression (p = 0.049). CONCLUSION: Although uTWEAK is not a superior biomarker compared to proteinuria, it has a significant correlation with IgAN patients and seems to be useful in determining disease progression.

Combined utilization of untimed single urine of MCP-1 and TWEAK as a potential indicator for proteinuria in lupus nephritis: A case-control study.

The aim of this study was to determine whether combined utilization of untimed single urine monocyte chemoattractant protein 1 (uMCP-1) and tumor necrosis factor (TNF)-like weak inducer of apoptosis (uTWEAK) could serve as a screening test for proteinuria in patients with lupus nephritis (LN).A case-control study that contained 39 biopsy-proven LN patients, 20 non-LN systemic lupus erythematosus (SLE) patients, and 10 healthy controls (HCs) were carried out. Correlations between uMCP-1, uTWEAK, and traditional clinical markers were analyzed by Spearman correlation test. Diagnostic values of uMCP-1, uTWEAK, and urine albumin/creatinine ratio (uACR) in the assessment of proteinuria were investigated by receiver operating characteristic (ROC) curves.Biopsy-proven LN patients showed higher levels of uMCP-1 and uTWEAK than non-LN patients. uMCP-1 and uTWEAK were elevated in renal active patients (rSLEDAI ≥4). Both uMCP-1 and uTWEAK showed significant correlation with patients' rSLEDAI, 24-hour urine proteinuria (24hr UP), and anti-double-stranded DNA (anti-dsDNA) antibodies. No correlations of these 2 biomarkers between cystatin C (Cys-C), creatinine (Cr), and blood urea nitrogen (BUN) were observed. An algorithm combining the moderate sensitivity of uMCP-1 and high specificity of uTWEAK displayed great specificity and sensitivity for proteinuria screening.Both uMCP-1 and uTWEAK were positively correlated with the impairments of LN, and the combined utility of untimed single uMCP-1 and uTWEAK might be used as potential predictors for proteinuria in LN.

Combined detection of uMCP-1 and uTWEAK for rapid discrimination of severe lupus nephritis.

Reliable markers for the rapid discrimination of severe renal damage remain a vital concern for lupus nephritis (LN). To determine a better tool for kidney damage detection, the present study compared the evaluation ability of novel urinary cytokines and chemokines (namely urinary monocyte chemoattractant protein 1 (uMCP-1), tumor necrosis factor-like weak inducer of apoptosis (uTWEAK)) with traditional serum or urinary markers (namely urinary alpha 1-microgrobulin (uα1-MG), beta 2-microglobulin (uß2-MG) and serum complement C3 (C3), complement C4 (C4), creatinine (Cr), blood urea nitrogen (BUN) and cystatin C (Cys C)) in discriminating LN renal damage. Correlations between markers with Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) renal SLEDAI scores, biopsy activity index (BAI) and biopsy chronicity index (BCI) scores were evaluated. Receiver operating characteristic (ROC) curves were generated to evaluate a single or combined model in discriminating active renal involvement (rSLEDAI scores > 0) and patients with poor pathological outcome (BAI scores ≥ 7). uMCP-1 and uTWEAK possess higher correlation coefficients with renal damage and larger areas under ROC curves (AUCs) than other markers. A combined model of uMCP-1 and uTWEAK showed an AUC of 0.887, sensitivity of 86.67% and specificity of 80.00% to discriminate active LN, and an AUC of 0.778, sensitivity of 75.00% and specificity of 81.82% to discriminate LN with poor outcome, which are better than the utility of any markers individually.

Assessment of urinary TWEAK levels in Mexican patients with untreated lupus nephritis: An exploratory study.

OBJECTIVES: Urinary levels of TWEAK (uTWEAK) may be correlated with the degree of lupus nephritis (LN) activity. Our objective was to determine the sensitivity and specificity of uTWEAK in Mexican patients with untreated active lupus nephritis. METHODS: An exploratory study was performed; four groups of patients were analyzed as follows: 1) patients with systemic lupus erythematosus (SLE) without renal activity (SLE-LN), 2) patients with SLE with renal activity (SLE+LN), 3) patients with other types of glomerulopathy (glomerulonephritis, GMN), 4) and healthy patients (controls). RESULTS: In all, 44 patients, with an average age of 35.9±11.5 years, were evaluated. uTWEAK levels were higher in patients with SLE+LN compared with patients in the other groups: SLE+LN 12.88±8.33, SLE-LN 3.12±2.31, GMN 4.36±2.31 and controls 2.41±1.94pg/mg Cr (p=0.007). A total of 72.7% of the cases had renal activity index scores above 12, and 90.9% of the cases had scores of chronicity below 6 points. Receiver Operating Characteristic (ROC) curve analysis revealed that uTWEAK levels above 4.91pg/mg Cr had a sensitivity of 81% and a specificity of 75% for the diagnosis of renal activity due to lupus, with an area under the curve of 0.876 (95% CI: 0.75-0.99). However, no significant correlation was observed between the levels of uTWEAK and the histological findings specific to the activity and chronicity associated with SLE. CONCLUSIONS: Our study revealed that uTWEAK can adequately distinguish renal activity due to lupus, but cannot predict the degree of histological activity in Mexican patients with active lupus nephropathy.

Urinary TNF-like weak inducer of apoptosis (TWEAK) as a biomarker of lupus nephritis.

BACKGROUND: Renal involvement in systemic lupus erythematosus (SLE), known as lupus nephritis (LN), is a common and severe complication and a major predictor of poor outcome. Long-term survival in SLE can be improved with early diagnosis and prompt treatment of LN. A number of biochemical markers are currently used to clinically assess disease activity in patients; however, they lack sensitivity and specificity for differentiating renal activity and damage in LN. A reliable clinical biomarker that can forecast LN flare and which could be sequentially followed would help to optimize initiation and escalation of therapy at the time of active or relapsing disease. OBJECTIVE: This study was carried out to investigate the value of urinary tumor necrosis factor (TNF)-like weak inducer of apoptosis (uTWEAK) as a biomarker for active lupus nephritis. PATIENTS AND METHODS: A total of 44 patients with SLE fulfilling the 1997 revised criteria for the classification of SLE as well as 11 age and sex-matched healthy controls were included in this study and subjected to full medical history taking, clinical examination, routine laboratory investigations, measurement of uTWEAK level as well as renal biopsy for patients with active LN. RESULTS: The uTWEAK levels were significantly higher in SLE patients with active LN compared to those without or with inactive renal disease and normal healthy subjects.