1. Tamm—Horsfall (T—H) glycoprotein has been measured by a specific radioimmunoassay method in the urine of patients with chronic renal failure, cadmium nephropathy and Lignac—Fanconi syndrome, and in renal and bladder calculi.
2. Total T—H glycoprotein excretion/24 h was markedly reduced in patients with chronic renal failure compared with normals. A highly significant correlation was observed between T—H excretion rate and creatinine clearance corrected for surface area, in both normals and patients with renal impairment. However, the mean T—H excretion per functioning nephron unit did not differ significantly in patients with renal failure compared with normals.
3. Total T—H excretion/24 h was in the normal range in patients with cadmium nephropathy despite reduced glomerular filtration rates, owing to a highly significant increase in T—H excretion per functioning nephron unit. Similar findings were obtained in a group of children with Lignac—Fanconi syndrome whose T—H excretion per functioning nephron unit was much higher than that of normal children in the same age range. This indicates an increased T—H glycoprotein excretion per functioning nephron unit in both these conditions.
4. T—H glycoprotein content of bladder and renal calculi ranged from 0002 to 5.07 mg/g of calculus. There was no correlation between T—H glycoprotein content and either the total protein content or the qualitative inorganic composition of the stones.