Urinary tissue factor (uTF), tissue factor pathway inhibitor (TFPI) and plasmin as novel biomarkers in early diagnosis of lupus nephritis.

Systemic lupus erythematosus (SLE) is an autoimmune inflammatory disease, with multi systematic affection. Lupus nephritis (LN) is the most frequent cause of renal damage in SLE patients with variable presentations that may progress to end stage renal failure. Coagulation disorders are frequently reported in SLE and LN with higher mortality rates. Renal biopsy is an invasive process, and the existing indicators for LN diagnosis and activity are unreliable. New urinary biomarkers with significant validity, safety, and accuracy are the current focus of most studies. Our study sought to assess the value of urinary tissue factor (uTF), tissue factor pathway inhibitor (TFPI), and plasmin as biomarkers for the early identification and detection of LN and its activity. This was a cross-sectional study, included 100 subjects (80 SLE patients, and 20 healthy controls), they were recruited from the Internal Medicine department, Rheumatology and Nephrology units and outpatient's clinics at Assiut University hospital between the period of 2020 and 2022. All patients underwent full history taking, clinical evaluation, and activity scoring calculation and laboratory investigations. The results showed that the best diagnostic accuracy of LN was observed with TFPI (90% accuracy, sensitivity 80% and specificity 95% with p <0.001 at cutoff point of >193.2 ng/ml), followed by uTF (75.4% overall accuracy at cut off point of >12.6 ng/ml, sensitivity 90% and specificity 68% with p < 0.001) and plasmin (70.3% accuracy at cut off point of >30.5 ng/ml, sensitivity 55% and specificity 78% with p < 0.001). Urinary TFPI was the best predictor of LN occurrence with odd ratio of 4.34, (p < 0.001). In conclusion urinary TFPI could be used as a diagnostic marker for LN with high accuracy and an early predictor of LN.

Serum and Urine Monocyte Chemoattractant Protein-1 as A Markers for Lupus Nephritis.

Lupus nephritis (LN) is a common major organ manifestation and main cause of morbidity and mortality of the disease. We aimed to determine the level of serum and urinary monocyte chemoattractant protein-1(sMCP-1 and uMCP-1) in systemic lupus erythematosus (SLE) patients with and without LN and analyze their association with different clinical and serologic parameters of disease activity. We enrolled 60 female patients with SLE (32 with LN and 28 without LN) and 20 controls.MCP-1 and anti-dsDNA were measured by ELISA. There was statistically significant increase in serum and urinary MCP-1 in all SLE patients (mean=711.59, 676.68 pg/ml respectively) as compared to the control group (mean= 635.70, 632.40 pg/ml respectively), P=0.034, 0.020 respectively. Among patients with LN there was statistically significant increase in sMCP-1 (mean=723.58) compared to the control group (P=0.038, and in uMCP-1 (mean=699.08) compared to patients without LN (mean=651.07) and control group (mean=632.40), P=0.007, 0.002 respectively. Urinary, but not serum MCP-1, positively correlated with 24 hour proteinuria, anti-dsDNA, renal SLEDAI ,biopsy activity index (r=0.362, P=0.004; r=0.303, P=0.019; r= 0.267, P=0.039; r=0.353, P=0.047 respectively) and negatively correlated with serum albumin (r=-0.329, P=0.010).There was statistically significant increase in uMCP-1 and anti-dsDNA in patients with poor response compared to patients with good response to immunosuppressant therapy (P= 0.025; P=0.034 respectively). In conclusion, uMCP-1 is associated with LN and disease activity and may be used as a useful tool for diagnosis and follow up.