Beneficial effects of creatine phosphate sodium for the treatment of Henoch-Schönlein purpura in patients with early renal damage detected using urinary kidney injury molecule-1 levels

Erythrocyte Glutathione S-Transferase Activity as a Sensitive Marker of Kidney Function Impairment in Children with IgA Vasculitis

IgA vasculitis (IgAV) is the most common childhood vasculitis. The main cause of morbidity and mortality in children with IgAV is nephritis (IgAVN), but the risk of its development, severity, and chronicity remain unclear. Erythrocyte glutathione S-transferase (e-GST) activity has been previously detected as a sensitive marker of kidney function impairment in several diseases. We spectrophotometrically assessed and correlated e-GST activity between 55 IgAV patients without nephritis (IgAVwN), 42 IgAVN patients, and 52 healthy controls. At disease onset, e-GST activity was significantly higher in IgAVN patients (median (interquartile range)) (5.7 U/gHb (4.4-7.5)) than in IgAVwN patients (3.1 U/gHb (2.2-4.2); p < 0.001), and controls (3.1 U/gHb (1.9-4.2); p < 0.001). Therewithal, there were no differences between the IgAVwN patients and controls (p = 0.837). e-GST activity was also significantly higher in the IgAVN patients than in the IgAVwN patients after 3 months (5.0 U/gHb (4.2-6.2) vs. 3.3 U/gHb (2.3-4.1); p < 0.001) and 6 months (4.2 U/gHb (3.2-5.8) vs. 3.3 U/gHb (2.1-4.1); p < 0.001) since the disease onset. Consistent correlations between e-GST activity and serum creatinine, estimated glomerular filtration rate (eGFR), and proteinuria levels were not detected. In conclusion, increased e-GST activity can serve as a subtle indicator of kidney function impairment in children with IgAV.

A systematic review of urine biomarkers in children with IgA vasculitis nephritis

BACKGROUND

Nephritis is a recognised complication of IgA vasculitis (IgAV, Henoch-Schönlein purpura) contributing to 1-2% of all chronic kidney disease (CKD) stage 5. Improved understanding may reduce irreversible damage in IgAV nephritis (IgAV-N).

OBJECTIVE

The aim of this study was to perform a comprehensive systematic literature review to identify promising clinical and pre-clinical urine biomarkers in children with IgAV-N that could predict the presence of nephritis and/or determine its severity.

METHODS

A systematic literature review was performed using four search engines and a predefined search term strategy. Promising biomarkers were divided in terms of clinical or pre-clinical and ability to predict the presence of nephritis or determine its severity. Results were described using statistical significance (p < 0.05) and area under the curve (AUC) values.

RESULTS

One hundred twenty-one studies were identified; 13 were eligible. A total of 2446 paediatric patients were included: healthy controls (n = 761), children with IgAV-N (n = 1236) and children with IgAV without nephritis (IgAV-noN, n = 449). Fifty-one percent were male, median age 7.9 years. The clinical markers, 24-h protein quantity and urine protein:creatinine ratio, were deemed acceptable for assessing severity of nephritis (AUC < 0.8). Urinary albumin concentration (Malb) performed well (AUC 0.81-0.98). The most promising pre-clinical urinary biomarkers in predicting presence of nephritis were as follows: kidney injury molecule-1 (KIM-1) (AUC 0.93), monocyte chemotactic protein-1 (MCP-1) (AUC 0.83), N-acetyl-β-glucosaminidase (NAG) (0.76-0.96), and angiotensinogen (AGT) (AUC not available). Urinary KIM-1, MCP-1, and NAG appeared to correlate with disease severity.

CONCLUSIONS

Longitudinal studies are needed to assess whether pre-clinical biomarkers enhance standard of care in IgAV-N.

Analysis of the association between kidney injury biomarkers concentration and nephritis in immunoglobulin A vasculitis: A pediatric cohort study

OBJECTIVE

The aim of this study was to investigate the clinical course, selected biochemical parameters and concentrations of renal injury biomarkers such as neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1) and liver-fatty acid binding protein (L-FABP) in patients with immunoglobulin A vasculitis (IgAV) to identify the markers associated with nephritis in the course of the disease (IgAVN).

METHODS

The study involved 29 children with IgAV and 34 healthy controls. Eleven (38%) patients had renal involvement (IgAV-N) and 18 (62%) did not exhibit nephritis (IgAV-noN). Initial laboratory tests, determining the concentrations of NGAL, KIM-1 and L-FABP in serum and urine, were conducted on children from the study group in an acute phase of IgAV as well as after an average of 6 months, during a follow-up visit. The interconnection between renal involvement, anthropometric measurements, epidemiological data, laboratory parameters and levels of examined biomarkers have been thoroughly evaluated.

RESULTS

The serum and urine levels of NGAL, KIM-1 and L-FABP were significantly higher in children with an acute phase of IgAV as compared to the control group (P < .001) and markedly lower during follow-up retesting in comparison with the values obtained at inclusion (P < .001). However, the concentration of none of the evaluated biomarkers correlated with nephrological indices. Among all examined parameters, only male subjects were associated with nephritis (P = .017).

CONCLUSIONS

We have established no evident association between the concentrations of NGAL, KIM-1 and L-FABP and nephritis in the course of IgAV in children. Additionally, we confirmed a significant male predominance in patients with nephritis.

Kidney Injury Molecule-1 Level is Associated with the Severity of Renal Interstitial Injury and Prognosis in Adult Henoch-Schönlein Purpura Nephritis

BACKGROUND AND AIMS

Kidney injury molecule-1 (KIM-1) was identified the most highly upregulated protein in chronic kidney diseases and prolonged KIM-1 expression may be maladaptive. The present study was aimed to investigate urinary, renal and plasma KIM-1 levels and to analyze association between KIM-1 levels with clinical and pathological indexes in adult Henoch-Schönlein purpura (HSP) patients.

METHODS

Twenty healthy individuals, 20 HSP patients without nephritis and 35 HSP patients with nephritis were recruited. Urinary and plasma KIM-1 levels were determined by ELISA and Luminex, respectively. Renal KIM-1 expression was evaluated by immunohistochemistry.

RESULTS

HSP patients with nephritis were characterized as elevated levels of urinary, renal and plasma KIM-1. Those with more severe tubular injury of renal biopsy tissues presented significantly higher urinary and renal KIM-1 levels compared to control and patients without nephritis. Urinary and renal levels of KIM-1 were positively correlated with blood urea nitrogen and proteinuria, while they were negatively correlated with eGFR at both baseline and after two years follow-up. Moreover, plasma KIM-1 levels were associated with blood urea nitrogen and proteinuria as well. Further univariate correlation analysis indicated urinary and renal KIM-1 levels were positively correlated with interstitial inflammation index and tubulointerstitial chronicity index. Only urinary KIM-1 levels were associated with interstitial inflammation index, tubulointerstitial chronicity index and extracapillary glomerular activity index, after logistic regression analysis. The area under the curve (AUC) for urinary KIM-1/Cr predicting progression of renal damage was significantly greater than the AUC for proteinuria.

CONCLUSIONS

This finding suggests that measurement of urinary and renal KIM-1 level may be helpful to evaluate severity of renal pathological damage and prognosis in adult HSP patients with nephritis.