Inclusion criteria

Inclusion Criteria:

  • 6 years of age or over
  • History of ulcerative colitis or Crohn’s disease
  • Normal creatinine  or eGFR  at baseline
  • ≥ 50% rise in serum creatinine, (with corresponding fall in eGFR), any time after introduction of 5-ASA
  • Medical opinion implicating 5-ASA justifies drug withdrawal, even if temporary.