1 Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114
A young child demonstrating opacification of the gallbladder following intravenous urography is described. This is the fourth reported instance of this phenomenon occurring in childhood although it is probably not a rare occurrence. Factors promoting the heterotopic biliary excretion of renal contrast media include prolonged recirculation of urographic contrast agents because of reduction in glomerular filtration rate due to intrinsic renal disease or ureteral obstruction; the current propensity for high doses of iodinated contrast agents for urography; gallbladder stasis; and, possibly, increased protein binding of urographic contrast media in the presence of uremic acidosis.