FMO5 and urolithiasis: After swallowing the CaOx crystals, macrophage cells can increase the expression of NAPDH oxidase in HK-2 cells, aggravate the inflammation, and induce the necrosis and denaturation of renal tubular epithelial cells; the basement membrane of renal tubular epithelial cells was exposed, thus promoting the formation of Randall plaques and even urolithiasis.