Título

ESTIMATION OF RESIDUAL KIDNEY FUNCTION WITH SERUM LEVELS OF Β2-MICROGLOBULIN IN PERITONEAL DIALYSIS

Introdução

Residual kidney function (RKF) is defined as the kidney function in patients with end-stage renal disease (ESRD) who are receiving dialysis. The ideal method to evaluate and measure RKF is still uncertain and the estimated glomerular filtration rate (eGFR) and urea clearance may over- and underestimate RFK, respectively. ß2-microglobulin (ß2M) is a 11818 Da protein freely filtered and metabolized in kidney tubules, thus its accumulation reflects an impaired RKF. Our study aimed to evaluate if serum levels of ß2MG could be used as a complementary tool for evaluating RKF in peritoneal dialysis (PD) patients.

Material e Método

For this retrospective cohort study, we evaluated 423 urine samples of 166 patients who were in the PD program of Hospital das Clínicas, HCFMUSP, Universidade de Sao Paulo, Brazil from Jan/01/2014 up to Aug/10/2020. We correlated serum ß2M levels with the urea renal Kt/V (urea clearance adjusted by the total body water (TBW), measured with bioimpedance), serum creatinine and urinary volume.

Resultados

We found a correlation between renal Kt/V and ß2 microglobulin (r= -0.656, p<0.0001), serum creatinine (r= -0.603, p<0.0001), and urinary volume (r= -0.682, p<0.0001). ROC curve revealed that ß2 microglobulin had a high performance to predict renal Kt/V, with a sensitivity of 70 to 81.7% according to the best cutoff. The specificity varied from 71.5% to 84.2%for Kt/V cutoff 0.5, 1.0, 1.5 and 2.0.

Discussão e Conclusões

Based on the good correlation between serum ß2M and urea renal Kt/V, we suggest that ß2M can be a useful tool to estimate the RFK. This findings can be particularly useful in patients who have difficulties in storing or collecting a 24-hour urine sample.

Palavras Chave

diálise peritoneal, beta-2 microglobulina, função renal residual

Área

Doença renal crônica

Instituições

HCFMSUP` - SAO PAAULO - São Paulo - Brasil

Autores

Fernando Louzada Strufaldi, Luciana Gil Lutf, Hugo Abensur, Rosilene Motta Elias