Urography in myelomatosis.

To investigate whether urographic contrast media might precipitate Bence Jones protein in the renal tubules and lead to renal failure in patients with myelomatosis, the reaction between the media and myeloma urine was studied in vitro. Appreciable precipitation was found only in urine at or below pH 4.5, and its occurrence did not correlate with the type or concentration of protein present. It is concluded that the risk of urography in myelomatosis is very small.