Acute Phosphate Nephropathy with Diffuse Tubular Injury Despite Limited Calcium Phosphate Deposition

Intern Med. 2016;55(16):2229-35. doi: 10.2169/internalmedicine.55.5864. Epub 2016 Aug 15.


An 86-year-old woman developed acute kidney injury after colonoscopy. A renal biopsy showed diffuse tubular injury with minimal calcium phosphate deposits (CPDs), which were thought to be caused by an oral sodium phosphate bowel purgative before colonoscopy. According to these findings, she was diagnosed with acute phosphate nephropathy (APhN). In contrast to previous reports of diffuse tubular injury associated with tubular CPDs in APhN, this case demonstrated diffuse tubular injury despite a limited distribution of CPDs, suggesting that calcium phosphate can cause tubular injury without deposition. This case thus supports the hypothesis that urinary calcium phosphate crystals may cause tubular injury via other mechanisms, including inflammatory cytokines.

Publication types

  • Case Reports

MeSH terms

  • Acute Kidney Injury / chemically induced*
  • Acute Kidney Injury / pathology
  • Aged, 80 and over
  • Cathartics / administration & dosage
  • Cathartics / adverse effects*
  • Colonoscopy / adverse effects
  • Female
  • Humans
  • Phosphates / administration & dosage
  • Phosphates / adverse effects*


  • Cathartics
  • Phosphates
  • sodium phosphate