BIOM3002 Lecture Notes - Lecture 4: Ulcerative Colitis, Epithelioid Cell, Colorectal Polyp
26 May 2018
School
Department
Course
Professor
HISTOPATHOLOGY LECTURE FOUR
Describe the features of IBD:
o IBD = umbrella term from disorders that involve chronic
inflammation of the digestive tract
o Ulcerative colitis – long lasting inflammation and sores
[ulcers] in the innermost lining of the colon and rectum
o Crohn's Disease – indeterminate colitis, characterised by
inflammation of the digestive tract lining, often spreading
deep into affected tissues [transmural]
o Impossible to differentiate in 15% IBD patients
IBD symptoms vary, depending on severity of inflammation and
where it occurs:
o Diarrhoea
o Fever and fatigue
o Abdominal pain and cramping
o Blood in stool
o Reduced appetite
o Unintended weight loss
Crohn's disease and UC – gross pathology:
o There are skip lesions in CD, not in UC [usually begins in
rectum and spreads on LI] and histologically no granulomas
Crohn's disease pathology:
o Characterised by transmural [full wall thickness]
inflammation, involvement of discontinuous segments of
intestine [skip lesions], and, in a proportion of cases, by
non-narcoticizing granulomas [where centre of granuloma is
not dead] composed of epithelioid histocytes/macrophages
Note: cobblestone appearance [pseudo polyps] not dysplastic,
just outgrowths
What is a granuloma?
o Body/structure with a granular look histologically
o Collection of immune/phagocytic cells [macrophages, here
called epithelioid cells], fibrous tissue and lymphocytes
o Form in many chronic inflammatory conditions
o There is an overactivity of the immune system as it attempts
to wall-off substances it perceives as foreign but is unable
to eliminate
o Necroticizing granulomas have a necrotic core [typical in
TB]
o Macrophages can fuse to form giant cells – number of nuclei
= number of macrophages fused
o Fibrocytes often around border
Ulcerative colitis – pathology:
o Inflammation is limited to the mucosal layer of the colon
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Describe the features of ibd: ibd = umbrella term from disorders that involve chronic inflammation of the digestive tract, ulcerative colitis long lasting inflammation and sores. [ulcers] in the innermost lining of the colon and rectum: crohn"s disease indeterminate colitis, characterised by inflammation of the digestive tract lining, often spreading deep into affected tissues [transmural, impossible to differentiate in 15% ibd patients. Ibd symptoms vary, depending on severity of inflammation and where it occurs: diarrhoea, fever and fatigue, abdominal pain and cramping, blood in stool, reduced appetite, unintended weight loss. Crohn"s disease and uc gross pathology: there are skip lesions in cd, not in uc [usually begins in rectum and spreads on li] and histologically no granulomas. Crohn"s disease pathology: characterised by transmural [full wall thickness] inflammation, involvement of discontinuous segments of intestine [skip lesions], and, in a proportion of cases, by non-narcoticizing granulomas [where centre of granuloma is not dead] composed of epithelioid histocytes/macrophages.
