TY - JOUR

T1 - URINE CONGO-RED DOT TEST AS A NON-INVASIVE SCREENING METHOD FOR RENAL AMYLOIDOSIS

AU - Anpilova, A.

AU - Khrabrova, M.

AU - Galkina, O.

AU - Rubel, A

AU - Smirmov, A.

AU - Чернов, Юрий Олегович

PY - 2021/4/1

Y1 - 2021/4/1

N2 - Introduction: Amyloidosis is a heterogeneous group of disorders characterized by extracellular deposition of fibrillar structures consisting of aggregated abnormal proteins with cross-β spine conformation. Any type of renal amyloidosis (RA) is associated with a poor renal prognosis. Diagnosis of RA requires morphological confirmation that may be limited in some categories of patients. Currently, there is no screening non-invasive method to diagnose RA. The aim of this pilot study was to evaluate the validity of the Congo-Red Dot (CRD) test based on urine protein staining with Congo-Red (CR) Dye as a screening method for RA in patients with different degrees of proteinuria. Methods: For CRD test the urine samples from patients with a morphologically verified diagnosis of renal amyloidosis (RA, n = 16), non-amyloid variant of nephropathy (NN, n = 25), and the control group (n = 32) were evaluated. Protein-creatinine ration (PCR) from 24 hour urine collection was estimated in all patients. For CRD test 4 μl of urine after centrifugation was mixed with 2 μl of Congo-Red Dye solution and spotted in duplicates on a nitrocellulose membrane of 0.45 μm. Spots on the membrane were photographed in the specially designed photocamera before and after washing with increasing concentration of ethanol (1 min in 50%, then 1 min in 70%, and finally 60 min in 90% ethanol). The intensity of CR staining on membrane before and after washing was estimated by difference in spots brightness by ImageJ software. Congo-Red Retention (CRR, %) was calculated with formula: (spot brightness after washing in ethanol/ spot brightness before washing in ethanol)*100%. Urine sample from patient with preeclampsia and urine sample from a health person with no proteinuria were used as a positive and negative control, respectively. Data are presented as median and interquartile range (M (25%; 75%)). To assess the significance of differences between groups, the nonparametric Mann-Whitney test was used. Spearman's correlation analysis was used to investigate the relationships between the variables. Receiving operating characteristic (ROC) curve was generated to assess the utility of CRR in prediction of RA. Differences were considered statistically significant at p

AB - Introduction: Amyloidosis is a heterogeneous group of disorders characterized by extracellular deposition of fibrillar structures consisting of aggregated abnormal proteins with cross-β spine conformation. Any type of renal amyloidosis (RA) is associated with a poor renal prognosis. Diagnosis of RA requires morphological confirmation that may be limited in some categories of patients. Currently, there is no screening non-invasive method to diagnose RA. The aim of this pilot study was to evaluate the validity of the Congo-Red Dot (CRD) test based on urine protein staining with Congo-Red (CR) Dye as a screening method for RA in patients with different degrees of proteinuria. Methods: For CRD test the urine samples from patients with a morphologically verified diagnosis of renal amyloidosis (RA, n = 16), non-amyloid variant of nephropathy (NN, n = 25), and the control group (n = 32) were evaluated. Protein-creatinine ration (PCR) from 24 hour urine collection was estimated in all patients. For CRD test 4 μl of urine after centrifugation was mixed with 2 μl of Congo-Red Dye solution and spotted in duplicates on a nitrocellulose membrane of 0.45 μm. Spots on the membrane were photographed in the specially designed photocamera before and after washing with increasing concentration of ethanol (1 min in 50%, then 1 min in 70%, and finally 60 min in 90% ethanol). The intensity of CR staining on membrane before and after washing was estimated by difference in spots brightness by ImageJ software. Congo-Red Retention (CRR, %) was calculated with formula: (spot brightness after washing in ethanol/ spot brightness before washing in ethanol)*100%. Urine sample from patient with preeclampsia and urine sample from a health person with no proteinuria were used as a positive and negative control, respectively. Data are presented as median and interquartile range (M (25%; 75%)). To assess the significance of differences between groups, the nonparametric Mann-Whitney test was used. Spearman's correlation analysis was used to investigate the relationships between the variables. Receiving operating characteristic (ROC) curve was generated to assess the utility of CRR in prediction of RA. Differences were considered statistically significant at p

UR - https://www.mendeley.com/catalogue/ed43c237-c161-3111-9726-35c1858a7d67/

U2 - 10.1016/j.ekir.2021.03.513

DO - 10.1016/j.ekir.2021.03.513

M3 - Meeting Abstract

VL - 6

SP - S210-S211

JO - Kidney International Reports

JF - Kidney International Reports

SN - 2468-0249

IS - 4

T2 - ISN World Congress of Nephrology (WCN)

Y2 - 15 April 2021 through 19 April 2021

ER -