Resolution of muscle calcification in rhabdomyolysis and acute renal failure.

We studied four patients with acute renal failure associated with nontraumatic rhabdomyolysis to evaluate the presence and progression of calcium deposits in damaged muscle tissue. Conventional and electron radiography and technetium-99m diphosphonate (TcDP) scans were done during the oliguric phase of acute renal failure and repeated after renal function returned to normal. Three patients showed deposits of calcium by conventional radiography and all by electron radiography and TcDP during the oliguric period. When the patients recovered renal function and muscle injuries healed, calcium deposits disappeared. The results show that calcium deposits in damaged muscle occur during the oliguric phase of acute renal failure due to rhabdomyolysis and the calcification disappears with recovery of renal failure; and TcDP scans are the most sensitive method of detecting calcium deposits in these patients.