Approach to the pt with hematuria. ANCA, antineutrophil cytoplasmic antibody; ASLO, antistreptolysin O; GBM, glomerular basement membrane; VDRL, Venereal Disease Research Laboratory. (From Lin J, Denker BM: Azotemia and urinary abnormalities, in Kasper DL et al (eds). Harrison's Principles of Internal Medicine, 19th ed. New York, NY: McGraw-Hill; 2014.)