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What is Following statements regarding ulcerative colitis is true- ( and explain in detail?
Ulcerative colitis Inflammation invariably involves the rectum (proctitis) and spreads and also has some bleeding and proximally in a continuous manner to involve the entire colon in some cases (pancolitis). In long-standing pancolitis, the bowel can become shoened and post-inflammatory 'pseudopolyps' develop; these are normal or hyperophied residual mucosa within areas of atrophy . The inflammatory process is limited to the mucosa and spares the deeper layers of the bowel wall . Both acute and chronic inflammatory cells infiltrate the lamina propria and the crypts ('cryptitis'). Crypt abscesses are typical. Goblet cells lose their mucus Ref Davidson edition23rd pg 815