Ulcerative colitis is a chronic condition in which the large intestine (colon) becomes inflamed with ulcers that cause diarrhea and bleeding. Ulcerative colitis generally affects the lower part of the colon and the rectum, though can affect the entire colon.
Ulcerative colitis is a type of inflammatory bowel disease (IBD). Another type of IBD is Crohn’s disease, which can affect any part of the gastrointestinal tract from the mouth to the anus.
Symptoms of ulcerative colitis vary and mild symptoms occur in about half of all patients. The first symptoms of ulcerative colitis may include:
- Loose and urgent bowel movements
- Frequent need to empty the bowels
- Bloody stool
- Abdominal cramps and pain
- Persistent diarrhea accompanied by abdominal pain and blood, mucus, or pus in the stool
Other symptoms of ulcerative colitis may include:
- Rectal bleeding
- Rectal pain
- Painful urge to move the bowels caused by the inflammation
- Fatigue/tiredness
- Loss of appetite
- Weight loss
- Fever
- Night sweats
- Dehydration
Patients with ulcerative colitis often have relapses, when inflammation and symptoms worsen (flares), followed by periods of remission, that can last months to years when symptoms subside.
What Causes Ulcerative Colitis?
It is not known what causes ulcerative colitis, but it is believed to involve an abnormal activation of the immune system in the intestines, causing chronic inflammation and ulceration in portions of the large intestine.
This susceptibility to abnormal activation of the immune system is genetically inherited. Having a first-degree relative (brother, sister, child, and/or parent) who has ulcerative colitis is a risk factor for developing ulcerative colitis.
How Is Ulcerative Colitis Diagnosed?
Ulcerative colitis is diagnosed with a physical exam and patient history and tests such as:
- Stool testing
- To check for and rule out infection or parasites
- Calprotectin
- Blood tests
- Complete blood count (CBC)
- Sedimentation rate
- C-reactive protein
- Liver function tests
- Kidney function
- Iron studies
- Colonoscopy or sigmoidoscopy
- Barium enema X-ray
- Video capsule endoscopy
- CT/MRI enterography
- Tissue biopsy
What Is the Treatment for Ulcerative Colitis?
Ulcerative colitis is usually treated with medications to bring about or maintain remissions and improve quality of life. Surgery is a last-resort for patients who have severe inflammation and life-threatening complications.
Medications used to treat ulcerative colitis include:
- Anti-inflammatory drugs
- 5-ASA compounds
- Balsalazide (Colazal)
- Mesalamine (Asacol, Pentasa, Rowasa, Lialda, Apriso)
- Olsalazine (Dipentum)
- Systemic corticosteroids (prednisone, prednisolone, cortisone)
- Topical corticosteroids
- 5-ASA compounds
- Immunomodulators
- Azathioprine/6-MP (Imuran, Azasan)
- Methotrexate (Trexall, Otrexup)
- Cyclosporine (Sandimmune, Neoral)
- Biologic therapies
- Infliximab (Remicade)
- Janus kinase inhibitors (JAK Inhibitors)
Surgery for ulcerative colitis is a last-resort and is reserved for severe cases. Surgery usually involves removing the entire colon and the rectum, which is the only permanent cure for ulcerative colitis.
From 
https://pubmed.ncbi.nlm.nih.gov/8613037/
https://www.crohnscolitisfoundation.org/