“…Subcapsular or perirenal fluid may result from urine leakage, 121 hemorrhage, 128 abscess, 71,91,117,120,129,130,134 acute renal failure, 121 ureteral obstruction, 121 toxicity 76,121 (e.g., ethylene glycol), leptospirosis, 77,121 transplant rejection, 135 or renal neoplasia (Figure 16-26, A). With smaller amounts of fluid, it may be difficult to determine if the fluid is subcapsular or perirenal and therefore they are considered together here.…”