Hello Welcome to health care magic Dear patient, the type of the stool you describe, we call it pale cley coloured stools, it is generally found in bile duct obstruction either due to stone, stricture, worm growth or any other reason, and bile duct obstruction besides causing pale cley coloured stools also causes, jaundice, itching, abdominal pain and vomiting dark coloured urine etc. In your case where the patient has been diagnosed with inflammatory colitis, may be ulcerative colitis 2 years back ,such patients develope bile duct obstruction due to a condition of the billiary tract known as primary sclerosing cholingitis, so if your wife also has jaundice, itching, abdominal pain ,and vomiting, swelling over abdomen and feet and dark coloured urine then her cley coloured stools indicate that she may be developing prmary sclerosing cholingitis other wise it could just be an incidental finding ,You consult a doctor and get your test done like LFT, USG whole abdomen, stool test, urine for routine and microscopy and if necessary MRCP(megnitic resonance cholangopancreatography) also to find the status of her billiary tract wish you best of luck thanks Dr Arshad