What is acute phosphate nephropathy?
Acute phosphate nephropathy (also called acute nephrocalcinosis) presents as acute renal failure with minimal proteinuria and a bland urine sediment in patients recently exposed to OSP. Renal biopsy reveals acute and/or chronic renal tubular injury (depending on time to diagnosis) with calcium-phosphate crystal deposition in the distal tubules and collecting ducts and no other pattern of histological injury. Bowel cleansing with OSP causes dehydration, decreased intravascular volume, and hyperphosphatemia (due to a large oral phosphate load). The hyperphosphatemia increases phosphate levels in the renal tubules. Decreased intravascular volume stimulates reabsorption of water from the renal tubules further increasing the phosphate concentration in renal tubular fluid. An abnormally high [Ca 2+][PO 4 2-] product in renal tubular fluid causes precipitation of calcium-phosphate crystals in the kidney and the pattern of renal injury described above. Who may be at risk? Patients with the fol
