Demographics and laboratory values.

<p>Demographics and laboratory values.</p

Dual colour confocal microscopy of urinary sediment.

<p>A) Kidney epithelial cell originating from the proximal tubule identified by AQP1 positive staining (green). TIMP-2 expression (red) is also present to high extent. The cell shows signs of membrane lesion and the nucleus is condensed. Cell debris (>) positive for AQP1. B) One AQP1/TIMP-2 (green/red) proximal tubule cells and TIMP-2 positive epithelial cell (red) not originating from the proximal tubule. C) AQP1/TIMP-2 (green/red) positive proximal tubule cell showing nuclear fragmentation (>) in form of apoptotic bodies from patient #2 at the time point when urine production started.</p

Correlation of NC-score with relative change of TIMP-2 and IGFBP7 expression, sCr and CRP.

<p>A) Pearson square pairwise correlation of NC-score with relative change of TIMP-2 mRNA expression in urinary sediment cells taking three normal kidney tissues as reference level. B) Pearson square pairwise correlation of NC-score with relative change of fold IGFBP7 change in urinary sediment cells taking three normal kidney tissues as reference level. C) Pearson square pairwise correlation of NC-score with serum creatinine levels (mg/dl) (r = -0.0283, p = 0.3995). D) Pearson square pairwise correlation of NC-score with CRP (mg/dl) (r = 0.3382, p = 0.0009).</p

Underlying diseases most likely causing AKI.

<p>Underlying diseases most likely causing AKI.</p

NC score, sCr and normalized fold TIMP-2 expression of representative patient #2.

<p>A 74 year old male patient having received a cadaver renal allograft from a 79-year-old donor showing delayed graft function and histologically verified signs of antibody mediated rejection. He underwent 12 sessions of immunoapharesis (IA) using a protein A column. His renal function gradually was improving and so the NC score as well as the urinary cell count and cell morphology.</p

Table of confounders and individual patients´ demographics.

<p>Table of confounders and individual patients´ demographics.</p

The urine biomarker panel [IGFBP7]x[TIMP-2] (NephroCheck^® parameter) does not correlate with IGFBP7 and TIMP-2 gene expression in urinary sediment

<div><p>Background</p><p>Acute kidney injury (AKI) is frequently observed in serious infections, following nephrotoxic medication, surgery and trauma. Here we tested whether the detection of two recently identified biomarkers for AKI, Tissue Inhibitor of Metalloproteinase-2 (TIMP-2) and Insulin-Like Growth Factor Binding Protein 7 (IGFBP7), depends on the expression of these proteins in cells of the urinary sediment.</p><p>Method</p><p>We collected urine samples of 33 kidney transplant recipients and 14 non-transplanted patients who all had AKI (stages 1–3 according to KDIGO), and measured [IGFBP7]x[TIMP-2] using the NephroCheck^® Astute1 40 ^™ meter. Concomitantly, we analyzed IGFBP7 and TIMP-2 mRNA expression by quantitative polymerase chain reaction (qPCR) from urinary sediment of the same patients, and correlated the results with [IGFBP7]x[TIMP-2] (protein), by linear regression analysis. We also determined the association between [IGFBP7]x[TIMP-2] and estimated glomerular filtration rate (eGFR), and between IGFBP7 and TIMP-2 mRNA expression and markers of inflammation. Light microscopy and confocal immunofluorescence served to illustrate changes in the urinary sediment over the time course of renal function improvement.</p><p>Results</p><p>Of the 47 analyzed AKI patients, 14 presented with ascending urinary tract infection. Serum creatinine (sCr), blood urea nitrogen (BUN) and eGFR in all patients were 3.9±2.28 mg/dL, 47.59±23.1 mg/dL and 22.88±16.0 mL/min/1.73m², respectively, on average ±standard deviation. [IGFBP7]x[TIMP-2] was 2.33±9.95 (ng/ml)²/1000, and did not associate with IGFBP7 and TIMP-2 gene expression (r = -0.0220, p = 0.4216; respectively r = 0.0972, p = 0.1909). [IGFBP7]x[TIMP-2] did not associate with eGFR; IGFBP7 and TIMP-2 mRNA expression. Improvement of renal function went along with disappearance of casts, decrease in aquaporin1 positive renal epithelial cells and leukocytes from the urinary sediment.</p><p>Conclusion</p><p>The gene expression pattern of IGFBP7 and TIMP-2 from urinary sediment, which contains desquamated renal tubular epithelial cells, did not correlate with [IGFBP7]x[TIMP-2] protein, indicating that IGFBP7 and TIMP-2 measured in the NephroCheck^® test originated predominantly from intact but stressed cells of the kidney itself.</p></div

Association between net perioperative fluid balance and changes in pre- to postoperative extracellular volume, with multiple levels of adjustments.

<p>Multiple regression analysis: After stepwise adjustment the coefficients of determination (r²), the p-value¹ for the combined effect of all predictors for each model, the p-value² for the individual effect of a predictor and the correlation coefficient (Beta) represent the association between the outcome and the predictor variables. Boldface indicating statistical significance (p<0.05).</p><p>Association between net perioperative fluid balance and changes in pre- to postoperative extracellular volume, with multiple levels of adjustments.</p

Associations between pre- to postoperative changes in volume status and net perioperative fluid balance.

<p>Scatter plots. Regression equations are as follows: <b>A</b> Change in Extracellular Volume = 0.73×Net Perioperative Fluid Balance –0.37. <b>B</b> Change in Total Body volume = 0.91×Net Perioperative Fluid Balance –0.43. <b>C</b> No linear correlation between Change in Intracellular Volume and Net Perioperative Fluid Balance. <b>D</b> No linear correlation between Change in Intracellular Volume and Change in Extracellular Volume. Pearson correlation test. R² = Coefficient of determination.</p

Demographic characteristics of the study population.

<p>Continuous variables are reported as mean ± standard deviation, (5^th and 95^th percentile); categorical variables are presented as counts and frequencies. Abbreviations: ASA = American Society of Anaesthesiologists’ physical status classification system, NYHA = New York Heart Association functional classification, PONV = postoperative nausea and vomiting, IV = intravenous. Net perioperative fluid balance = total perioperative intravenous fluid volume, corrected for urinary excretion and blood loss. *In 5 cases, the interval between the BCM-measurements was >60 minutes longer than the duration of anaesthesia, due to logistical reasons.</p><p>Demographic characteristics of the study population.</p