The present invention relates to a method of detection of an early-stage renal disease, comprising determining the concentration of human lipocalin-type prostaglandin D synthase in a body fluid sample taken from a subject and comparing the determined concentration with a reference value set by determining the concentrations of human lipocalin-type prostaglandin D synthase in body fluid samples taken from healthy subjects; and a method of disease state management for a renal disease, comprising determining the concentration of human lipocalin-type prostaglandin D synthase in a body fluid sample taken from a subject and evaluating the glomerular filtration ability of the subject from the determined concentration.