Lower GI Tract Flashcards
List the 7 main structures within the colon (large intestine)
Appendix
Caecum
Ascending colon
Transverse colon
Descending colon
Sigmoid colon
Rectum (—>anus)
List the 3 major organs supplied by the celiac artery
Stomach
Liver
Spleen
List the 3 major organs supplied by the superior mesenteric artery
Small intestine
Large intestine
Pancreas
Name the organ supplied by the inferior mesenteric artery
Colon
Name the major vein where the majority of organs in the gastrointestinal tract drains blood into.
Portal Vein
List the 4 major layers of the GI tract
Mucosa
Submucosa
Muscularis
Serosa
List the 3 components which make up the mucosa
From innermost to outermost:
Epithelium
Lamina propria
Muscularis mucosae
List the 2 components which make up the muscularis
From innermost to outermost:
Circular muscle
Longitudinal muscle
List the 2 components which make up the serosa
From innermost to outermost:
Areolar connective tissue
Epithelium
State the nerve responsible for parasympathetic innervation of the ascending and transverse colon.
Vagus nerve
State the nerve responsible for parasympathetic innervation of the distal portions of the colon (e.g descending, sigmoid)
Pelvic nerves
State vertebral regions of the spinal cord responsible for supplying sympathetic innervation of lower GI tract
Lower thoracic
Upper lumbar
External anal sphincter is supplied by which nerves and fibres?
Somatic motor fibres supplied by pudendal nerves
State what afferent sensory nerves of the lower GI tract are responsible for detecting.
Detects pressure
State the name of the plexus which innervates the submucosa of the GI tract
Meissner’s plexus
Define Hirchsprung’s Disease and its cause
Disorder of the lower GI tract in which there is difficulty in passing stool
Caused by lack of enteric intramural ganglia in most ditsal portions of the colon
State the region where myenteric ganglia is located
Taenia coli (The longitudinal ribbons of smooth muscle lining the colon)
State the 5 main types of lower GI tract disorders
Inflammatory
Infective
Structural
Functional
Neoplastic
Give 2 examples of inflammatory lower GI tract disorders
Inflammatory bowel disease
Microscopic colitis
Give 2 examples of infective lower GI tract disorders
E coli
C diff (Clostridium difficile)
Give 3 examples of structural lower GI tract disorders
Fissure
Haemorrhoids
Diverticular disease
Give an example of a functional lower GI tract disorders
Irritable bowel syndrome (IBS)
Give 2 examples of neoplastic lower GI tract disorders
Colon cancer
Colonic polyps
List 3 other causes for lower GI tract disorders besides those of the main divisions
Vascular causes
Metabolic causes
Neurological causes
State the incidence of inflammatory bowel disease in america and europe.
- 5 million americans
- 2 mil europeans
Which demographic of indiviudals are most affected by inflammatory bowel disease?
Young adults
List some socioeconomic complications for individuals suffering from IBS
- Burden of therapy for patients
- Hospitalisation
- Surgery
- Health-related quality of life
- Economic productivity
- Social functioning
State the 2 main conditions which fall under the umbrella term of inflammatory bowel disease
Crohn’s Disease
Ulcerative colitis
Define ulcerative colitis
A lower GI tract inflammatory disorder characterised by inflammation of the colonic mucosa
Define Crohn’s disease
An inflammatory disorder of the GI tract characterised by presentation of chronic transmural granulomatous inflammation
State 4 main ways Crohn’s disease differs to ulceratve colitis.
1) Can affect any part of the GI tract whereas in UC it is limitted to the colonic mucosa (hence superficial)
2) Crohn’s presents with granulomas whereas UC doesnt
3) Crohn’s affects more females versus males (5:1). UC affects both equally
4) UC extends in a continuous manner wheres in Crohn’s can affect different areas in a non continous way
Ulcerative Colitis always involves which part of the lower GI tracts?
Rectum
Describe the way inflammation presents itself in Crohn’s Disease
Patchy chronic transmural granulomatous inflammation
List the 5 main types of ulcerative colitis from least continous to most continuous and state the areas affected
Proctitis (Rectum)
Proctosigmoiditis (Rectum + sigmoid colon)
Distal colitits (rectum–>descending colon)
Extensive colitis (rectum –> transverse colon)
Pancolitis (Entirety of the colon)
List the 6 main types of Crohn’s Disease and state the areas affected.
Gastroduodenal Crohn’s Disease (Duoedenum [opening of SI])
Ileocolitis (Ileum [Distal portion of SI] and the LI)
Ileitis (Ileum)
Jejunoileitis (Jejunum [mid portion of SI])
Crohn’s colitis (Colon)
Perianal Crohn’s (Rectum and anus)
What is the most common type of Crohn’s Disease?
Ileocolitis
Inflammatory bowel disease has a variety of symptoms depending on which areas are affected. List 4 potential symptoms that may arise with individuals with colitis
Bleeding
Diarrhoea
Urgency to empty bowels
Mucus in stool/diarrhea
. List 3 potential symptoms that may arise in individuals with perianal inflammation in IBS
Anal pain
Difficulty passing stool
Leakage
. List 5 potential symptoms that may arise in individuals with small bowel disease
Abdominal pain
Abdominal mass
Weight loss
Fatigue/Lethargy
Diarrhoea
List 4 regions which may display extra-intestinal manifestaions of IBD
Arthritic regions
Skin
Eyes
Liver
List 2 types of arthiritis that can be caused by IBD
Ankylosis spondylitis (Arthiritis in the spinal region)
Peripheral arthritis (e.g. joints of arms and legs)
List 2 skin manifestations in patients with IBD
Erythema nodosum
Pyoderma gangrenosum
Name 2 manifestations of IBD that presents itself within the eyes
Anterior veitis (Inflammation of middle layer of eye suchs as iris and cilliary body)
Iritis/Episcleritis
Name 2 manifestations of IBD that presents itself within the liver
Primary sclerosis cholangitis (PSC) [Scarring of the bile ducts]
Autoimmune hepatits
Inflammatory disease can occur by a combination of which 3 main factors?
Genetics
Environmental factors such as luminal microbiota
Immune response
Name 4 types of gene which can increase the risk of developing IBD
NOD2
HLA
ATP
IL23R
Name 2 types of antibodies which can increase the risk of developing IBD
ASCA (Anti-saccaromyces cervisia)
pANCA
Give 2 examples of environmental factors which can increase the risk of developing IBD
Luminal microbiota:
Mycobacterium paratuberculosi
MMR (Not definitive proof(
Define dysbiosis
Reduced diversity in the microbiota
List 3 main pathophysiologies that may arise from dysbiosis
Autoimmunity
Metabolic disorders
Allergy
List 11 factors that may increase the risk of dysbiosis
Appendectomy
Stress
Smoking
Sleep hygeine
Hygeine
Diet
UV exposure/Vitamin D
Microbiome
Medications (e.g. ABs)
Physical activity
Genetic susceptibility
Presence of which antibody increases risk of developing Crohn’s Disease?
Presence of which antibody increases risk of developing Ulcerative Colitis?
ASCA = CD
pANCA = UC
State the 3 main management goals for individuals with IBD
Induce clinical remission
Maintain clinical remission
Improve quality of life
State 3 other management goals for patients with IBD
Heal mucosa
Reduce hospitilisation/surgery and costs
Minimise IBD and therapy related complications
What are the 5 main treatment options for managing IBD?
Steroids
5 ASA (Drugs used to treat IBD)
Immune suppresants
Biologic therapy
Other: Diet, Exercise, ABs, FMT [faecal micribiota transplants], probiotics
Name 2 immune suppresants used when treating IBD
Azathioprine
Methotreaxate
Explain the pharmacodynamics of steroids
Steroid diffuse and enter nucleus where it binds to GRE (Gluccocorticoid response element).
This results in an increase of anti-inflammatory gene produts and an inhibition of pro-flammatory gene expression
State the 3 modes of delivery for steroids
Orally
IV
Rectal enemas (enemas are tools which inject of fluid/gas up the rectum)
How should steroids be used when treating patients with IBD?
Should only be used short term and a bridge to other therapies and should be used in the acutely unwell
List 3 psychiatric symptoms of steroid usage
Sleep disturbance
Sleepiness
Psychosis
List 5 dermatological symptoms of steroid usage
Cushingoid appearance
Hirsutism
Oedema
Acne
Abdominal striae
List 2 neurological symptoms of steroid usage
Pseudomotor cerebri
Neuropathy
State the main cardiological symptom of steroid usage
Hypertension
List 3 musculoskeletal symptoms of steroid usage
Myopathy
Osteoporosis
Aseptic necrosis of bone
List 2 endocrine symptoms of steroid usage
Adrenal cortex suppresion
Diabetes mellitus
List 2 immunological symptoms of steroid usage
Immunosupresion
Lymphocytopenia
List 2 opthalmic symptoms of steroid usage
Acute-angle glaucoma
Cataracts
State the main developmental complication of steroid usage
Growth retardation
State the 4 main pharmacodynamic actions of 5 ASA
Inhibition of pro-inflammatory cytokines (IL-1 and TNF-a )
Inhibition of the lipo-oxygenase pathway i.e. prostaglandin and leukotrienes
Scavenging of free radicals
Inhibition of NF-kB/ TLR via PPAR-gamma induction (perioxisome proliferator activated
receptor-gamma)
What are the 2 main overall effects of 5 ASA?
Some immunosuppresive activity – inhibiting T cell proliferation, activation and differentiation
Impairs neutrophil chemotaxis and activation
State the 2 methods of delivery for 5 ASA
Orally
Rectal
State 7 side effects of 5 ASA
Intolerance
Headache
Malaise
Pneumonitis (Inflammation of the lungs)
Pancreatitis
Diarrhoea
Renal impairment
Explain the pathophysiological actions of Azathioprine
Reduces the production of guanine and adenine ribonucleotides
Results in reduction of T and B lymphocytes, immunoglobulins and interleukins.
Also increases T cell apoptosis
Give 7 examples of side effects from azathioprine
Infections
Pancreatitis
Bone marrow suppresion
Malignancy/lymphoma
Allergic reactions (e.g. fever, malaise, rash)
GI disturbance
Hepatotoxicity (nodular regenerative hyperplasia)
List 8 things that should be checked before and during administration of azathiroprone to a patient
TPMT (Low levels detected = dont give)
HIV
Hep B/C
Chickenpox (cant give if they never had)
TB
Vaccinations
During administration:
Take frequent blood tests intitally
Maintenance blood tests
State the 2 ribonucleotides affected by azathioprine
Adenine
Guanine
Describe the pharmacodynamics of methotrexate and state its 2 effects
Mechanisms unknown however it affects DNA synthesis and cell replication
Main effects:
Increases adnosine production which is an anti-inflammatory metabolite
Increases apoptosis of peripheral T cells
How long does methotrexate take to start having effects?
3 months
What 2 types of patients should not be administered methotrexate?
Patients with liver diseases
Patients who are pregnant or planning to become pregnant
What should be monitored in patients taking methotrexate?
LFTs (Liver function tests)
FBCs (Detect abnormalities such from complications such as bone marrow suppresion)
What should be given to patients alongside methotrexate to reduce the chance of developing side effects?
Folic acid supplemets
How often should methotrexate be administered to patients?
Weekly
State 8 potential side effects from methotrexate.
Rash
Nausea
Mucositis
Diarrhoea
Bone marrow suppresion
Hypersensitive pneumonitis
Cirrhosis
Liver fibrosis
(N.B. High levels of liver enzymes in circulation indicates liver damage)
Why should methotrextae not be given to patients who are pregnant or are planning for pregnancy?
Methotrexate is a abortifacient so can early terminate pregnancies
Define abortifacient
A substance that is capable of causing abortion during pregnacy
How do methotrexate and azathioprine differ in terms of malignancy risks?
Unlike azathioprine, methotrexate has not been known to cause lymphomas
Also not know to attribute to development of skin cancers
Define biologics
A type of drug that reduces inflammatory damage
State the 5 effects of TNF-a
Increased inflammation
Increased cell infriltration
Increased CPR in serum (C-reactive protein)
Tissue remodelling
Compromised of barrier functioning
Name 2 biologics that have an anti-TNF-a effect
Infliximab
Adalimumab
Name a biologic that have an anti-a4ß7 effect
Vedolizumab
Name a biologic that have an anti-IL12/IL23 effect
Ustekinumab
State how infliximab is admnisitered and how frequent dosgaes should be given
IV administration
Dosages are given in a 0, 2, 6 weeks period
Maintenance dosage 8 weekly
How does adalimumab compare in terms of administration and dosage frequency versus infliximab?
Subcutaneously (self-injected)
Can be taken at home versus in hospital and is taken more frequently
Give 10 examples of potential side effects of biologics
Opportunistic infection
IV/site infections
Infections
Bone marrow suppresion (neutropenia)
Malignancy (Lymphoma)
Demyelinating diseases
Heart failure (congestive heart failure)
Autoimmunity
Hepatotoxicity
Cutaneous reactions such as psoriasis
anti-TNF drugs such as infliximab and adalimumab work best alongside which two types of medication and why?
Azathioprine
6-MP (aka mercaptopurine)
Has a superior effect in maintaining response and remission
Reduces rate of antibody formation
Dietary therapy for treating inflammatory bowel disease is most effective in which type of patients?
Young children
Dietary therapy in children with IBD can be just as effective as which other alternative treatment method?
Steroids
Dietary therapy is most effective for which disease?
Small bowel Crohn’s Disease
How effective are the use of antibiotics for treating IBD?
No hard evidence suggesting effectiveness however can help in treating sepsis
