Small Intestine, Large Intestine and Rectum Flashcards
Steatorrhoea
Passing of stool that is pale, oily and floats on water. Caused by malabsorption of fat.
Gliadin
Fraction of gluten coeliacs are sensitive too
Tropical Sprue
Causes folate deficiency, responds to antibiotics
Giardia Lamblia
Water borne unicellular parasite, causes hypogammaglobulinaemia. Treated with metronidazole
Whipples disease
Caused by Tropheryma whippelii and presents with weight loss, abdominal pain and malabsorption. Very rare and effects skin, brain, joints and cardiac.
Myenteric Plexus
Made up of Meissener’s plexus (base of submucosa) and Auerbach’s plexus (between 2 layers of muscularis propria)
Inflammatory Bowel Disease
Chronic inflammatory condition resulting from inappropriate and persistent activation of the mucosal immune system driven by the presence of normal intra-luminal flora.
Skip lesions
Distribution of Crohn’s disease, in which random patches of disease are distributed throughout GI tract
Ischaemic Enteritis
Ischaemic lesions effecting any section of the small or large bowel due to occlusion of blood vessel.
Infarcted bowel
Occlusion of coeliac, superior mesenteric or inferior mesenteric leading to large transmural injury in bowel.
Radiation Colitis
Inflammatory reaction to abnormal irradiation. Impairs proliferation activity of cells in bowel. Mimics IBD in presentation.
Appendicitis
Acute inflammation of the appendix.
Adenoma of large bowel
Development of polyps in large bowel. Can be tubular, villous or tubulovillous.
Colorectal adenocarcinoma
Glandular tumour in large bowel, presentation varies depending on left or right sided.
Dukes’ Staging
Staging algorithm for colorectal cancer (A-D)
Ulcerative Colitis
IBD that features continuous inflammation of the rectum and potentially colon.
Crohn’s Disease
IBD that features skip lesions of inflammations anywhere in the GI tract.
Anal Crohn’s
Formation of fistula due to Crohn’s disease that protrudes out of anus
Calprotectin
White cell protein in leukocytes of bowel, can be detected in stool test as marker of inflammation
Sclerosing cholangitis
Disease of the bile ducts that causes strictures and can lead to liver cirrhosis. Associated with ulcerative colitis.
Aminosalicylates (5ASA)
Drugs used to induce and maintain remission of IBD
Thiopurines
Immunosuppressive agents used in induction and maintenance of remission in IBD. Used as steroid sparing agents but have significant side effects too.
Ciclosporin
IV rescue therapy for IBD
Biologics
Monoclonal antibodies used the treatment of IBD
Infliximab
Biologic drug. Anti TNFalpha antibodies used to treat IBD.
Pouch procedure
Small bowel is mobilised and lengthened to create a false rectum.
proctocolectomy
Surgical removal of the rectum and most/all of large colon, patient is left with stoma
ileostomy
Opening made in abdomen during surgery, end is brought through opening to form stoma.
Micro-satellite instability
Defective DNA repair pathway genes
Adjuvant chemotherapy
Chemotherapy given post surgery
Neoadjuvant chemotherapy
Chemotherapy given pre surgery
Faecal occult blood test
Screening test for colorectal cancer, detects blood in stool
Scottish Bowel Screening Programme
Patients aged 50-74 invited to do at home FOBT every 2 years. Positive tests invited for colonoscopy.
Familial adenomatous polyposis
Autosomal dominant condition that causes development of multiple adenomas throughout colon. Patients usually undergo prophylactic proctocolectomy before they are 24. Screened annually.
HNPCC
Autosomal dominant condition featuring mutation in DNA mismatch repair genes, causing patients to develop early onset colorectal cancer. Screened every 2 years.
Pancolitis
Inflammation from rectum to caecum, bowel is ulcerated with thick wall
Toxic mega-colon
Advancement of ulcerative colitis, very thin colon wall that is ischemic
Diverticular disease
Formation of tiny pockets in the lining of the bowel
Right hemicolectomy
Removal of right sided of colon. Indicated for adenoma, cancer and Crohn’s disease.
Sigmoid colectomy
Removal of left side of colon.
Low anterior resection
Removal of rectum, colon joined directly to anal canal.
Appendectomy
Removal of appendix, requires division of appendiceal artery (branch of ileocolic)
Base of appendix
Site where the 3 teniae coli running along the large bowel merge.
Hirschprung’s myenteric plexus deficiency
Congenital condition in which internal anal sphincter is unable to relax and defecation is impossible.
Haemorrhoids
Disrupted and dilated anal cushions causing painless bleeding.
Anal cushions
Spongy vascular tissue that lines the anus
Prolapsing haemorrhoids
Haemorrhoids that are outside the annus
Dentate line
Point at which anus receives sensory supply (pain line)
Anal Fissure
Tear in the sensitive skin-lined lower anal canal distal to dentate line
Fistula-in-ano
Abnormal communication between 2 epithelial surfaces, track communicates between skin and anal canal/rectum
Goodsall’s rule
States that if anal fistula is anterior then interior opening is in a straight line from external opening but if it is posterior then internal opening is at 6 o’clock position, taking a torturous course.
Seton suture
Used for anal fistulas, canal filled with collagen.
