Ulcerative colitis
• * Is a chronic disease with remission and relapse presented with bloody diarrhea 
with abdominal cramps s.t fever and weight loss 
• * More in whites than blacks. 
• * No sex predilection. 
• * The onset of the disease is usually at 2nd -3rd decades. 
• * The pathogenesis is still unknown as with Crohn’s dis. but it results from many 
environmental factors that lead to loss of tolerance of the mucosa for normal 
flora in genetically susceptible individuals.

• It is characterized by:
• 1- It involves only the colon hence the name “colitis”
• 2- The involvement is continuous (not skip) starting from the rectum and ascend 
upwards in a continuous way till it reach the ileum (s.t. it involves the distal ileum 
where it is called backwash ileitis) 
• 3- It involves the mucosa and submucosa only (not transmural) 
• 4- The ulcer is superficial and never forms fissures or wall thickening or strictures 
• 5- There is no cobblestone appearance instead there is inflamed hyperemic mucosa 
with islands of regenerating mucosal cells forming the pseudopolyps

• Mic:
• * congested mucosa. 
• * Acute and chronic inflammatory cell infiltration of the lamina propria 
• * Crypt abscess (collection of neutrophils in the glandular lumen) 
• * There is goblet cell depletion 
• * No granuloma

:Complications of ulcerative colitis
1. toxic megacolon and perforation: severe cases are associated with 
inflammation of the muscularis propria and neuromuscular dysfunction 
leading to colonic dilation 
2. Colorectal carcinoma cause by continuous regeneration ? dysplasia?carcinoma. 
Colorectal carcinoma is the cause of death in an estimated 15% 
of inflammatory bowel disease patients; risk factors for 
developing colorectal carcinoma include:
• Duration of disease
• Extent of disease
3- Extraintestinal manifestations: 5% have associated primary 
sclerosing colongitis, others develop similar complications as in
Crohn disease and include migratory polyarthritis, sacroiliitis, 
ankylosing spondylitis, uveitis