<prompt> The typical appearance of spider leg on excretory urography is seen inHydronephrosisPolysystic kidneyMedullary sponge kidneyRenal cell carcinoma  <response>: REPEAT QUESTION polycystic kidney, an autosomal dominant disease, common in females; excretory urogram shows spider leg pattern - elongated and compressed renal pelvis with narrowed and stretched calyces over the cysts. Reference: emedicine.medscape.comaicle983281-workup 