Acute Phosphate Nephropathy
Antoine Abcar, MD; Aviv Hever, MD; Jasminder S Momi, MD; John J Sim, MD
Summer 2009 - Volume 13 Number 3
Acute phosphate nephropathy (APN) is an underrecognized cause of both acute and chronic renal failure.1 Individuals with decreased renal function who are exposed to high doses of phosphorous are susceptible to developing APN.2 The risk for APN is increased in patients with underlying chronic kidney disease, older age, and female sex and in patients taking angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, diuretics, or nonsteroidal anti-inflammatory drugs (NSAIDs).2 APN has been reported to occur after exposure to sodium-phosphate (NaP) bowel-cleansing solutions. Clinically, some patients may present acutely with severe elevations of serum phosphorous and acute kidney injury (AKI); however, the injury may take weeks after exposure to occur, or the finding of an elevated creatinine level may be discovered incidentally weeks or months after the ingestion of these bowel preparations.3 Therefore, a careful history is important for making this diagnosis. Renal biopsy demonstrates deposition of calcium and phosphorous with damage in the tubulointerstitium.4 Patients may have variable outcomes, with some having no recovery of renal function and others recovering some function. There is no particular intervention that can be instituted once the nephropathy occurs. Avoidance of NaP-based bowel-cleansing solutions, particularly by high-risk individuals, is key to preventing APN.