Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry-based profiling as a step forward in the characterization of peritoneal dialysis effluent

The aim of this study was to differentiate patients with glomerulonephritis and diabetic nephropathy using (i) peritoneal dialysate effluent, (ii) matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and (iii) bioinformatics tools. Profiles of peritoneal dialysate effluent were obtained using (a) sample preparation consisting of protein concentration through centrifugal concentrators and chemical-assisted protein depletion using DL-dithiothreitol, and (b) MALDI-TOF MS. A free open-source bioinformatics tool, Mass-UP, was used to classify such profiles using principal component analysis and hierarchical clustering. The methodology proposed here allows for classifying two different groups of patients with kidney failure, one with chronic glomerulonephritis and other with diabetic nephropathy.