Small + large intestine conditions Flashcards
1
Q
Name 2 malabsorption disorders of the SI
A
Coeliac disease
Crohn’s (doesn’t just affect SI)
2
Q
Define maldigestion v malabsorption
A
Maldigestion = Impaired breakdown of food in the intestinal lumen, e.g. lack of pancreatic enzymes, following gastric resection, bile acid deficiency
Malabsorption = Impaired absorption of digested food caused by alterations of the intestinal mucosa
3
Q
Are Crohn’s disease and coeliac disease malabsorptive or maldigestive disorders
A
Malabsorptive
4
Q
General symptoms (3) /signs (5) of malabsorption
A
Increased appetite
Bloating
Fatigue
Weight loss Diarrhoea Steatorrhoea (fat malabsorption --> fatty stool) Clubbing Apthous ulcers (crohn's)
5
Q
Signs of iron deficiency (4)
A
Anaemia:
- Fatigue
- Pale skin
- Dyspnoea on exertion
- Koilonychia
6
Q
Sign of vitamin A deficiency
A
Night vision impaired
7
Q
Sign of vitamin K deficiency
A
Raised prothrombin time
8
Q
Signs of vitamin
-B1
-B3
deficiency
A
Vitamin B1 (thiamine) deficiency –> memory loss
Vitamin B3 (niacin) deficiency –> dermatitis
9
Q
Sign of vitamin C deficiency
A
Scurvy
10
Q
Investigations of small intestine disorders (6)
A
Endoscopy + biopsy Barium follow through Enteroscopy - longer version of endoscopy CT MRI enterography Capsule enterography - pillcam
11
Q
Investigations of bacterial overgrowth in SI (2)
A
H2 BREATH TEST (diagnostic of SI bacterial overgrowth and carbohydrate malabsorption)
Endoscopy + aspiration of duodenal/jejunal fluid –> then culture
12
Q
What is coeliac disease
A
Autoimmune disease triggered by gluten (specifically gliadin component of gluten)
Sensitivity to gluten
13
Q
Pathophysiology of coeliac disease
A
Immune activation –> inflammatory response to gliadin –> body produces anti-tissue transglutaminase) antibodies attacking the enzyme, tissue transglutaminase (tTG)), –> villous atrophy, hypertrophy of crypts and increased lymphocytes
14
Q
Risk factors of coeliac disease (3)
A
Family history of coeliac
PMH or FH of autoimmune diseases - type 1 DM, thyroid disease
IgA deficiency
15
Q
Symptoms (4) /signs (5) of coeliac disease
A
abdo pain
DIARRHOEA - most common
bloating,
fatigue
Steatorrhoea Weight loss Dermatitis herpetiformis (IgA deposit on skin) IgA deficiency Anaemia
16
Q
Investigations of coeliac disease (4)
- serology (3)
- gold standard
A
Serology (test for antibodies): -Total IgA - for IgA deficiency -IgA-tTG antibody -anti-endomysial IgA (Some coeliacs are IgA deficient so ALWAYS measure total IgA)
Distal duodenal biopsy – GOLD STANDARD
17
Q
Treatment of coeliac disease (2)
A
Gluten free diet
Nutritional support - calcium, vitamin D supplements
18
Q
What is the characteristic histological finding of coeliac disease
+ other histological findings (3)
A
Villous atrophy
intraepithelial lymphocytes,
mucosal atrophy
crypt hyperplasia
19
Q
What is the diagnostic investigation of coeliac disease
A
Distal duodenal biopsy
20
Q
Other causes of small intestine malabsorption (4)
A
Infection, e.g. tropical sprue, HIV, giardiasis
Whipple’s disease
Iatrogenic - e.g. following gastric resection
Pancreas insufficiency
21
Q
Treatment of small intestine bacterial overgrowth (3)
A
2 weeks each of:
Metronidazole
Tetracycline
Amoxycillin
22
Q
What is IBD
A
A collective name for chronic inflammatory conditions of the bowel
Results from inappropriate and persistent activation of the mucosal immune system
23
Q
Name the 3 types of IBDs
A
Crohn’s disease
Indeterminate colitis
Ulcerative colitis
24
Q
Pathophysiology of IBD
A
Unknown activation of the immune system –> immune response against normal flora of the colon
25
Cause of IBD
Idiopathic
Thought to be due to combo of:
- Environmental triggers
- Immune dysfunction - possibly autoimmune
- Genetic predisposition
26
What is ulcerative colitis + is it superficial/deep + where does the inflammation begin (3)
CONTINUOUS inflammation of the colon
Inflammation is SUPERFICIAL – limited to mucosa
Inflammation always starts from the rectum and moves proximally
27
Risk factors of UC (3)
Family history of UC
HLA-B27 gene
Infection
28
Symptoms (2) /signs (4) of UC
```
Abdo pain (LLQ)
Diarrhoea
```
Abdo tenderness
Rectal bleeding
Blood in stool
Malnutrition --> vit deficiencies, inable to maintain ideal weight
29
Symptoms/signs of a flare up/relapse of UC (worsened or additional symptoms to usual) (4)
Arthritis
Mouth ulcers
Irritated red eyes
Painful red swollen skin
30
Signs (4) of a severe UC attack
Stool frequency >6 a day with blood
Fever
Tachycardia
Dyspnoea
31
Investigations of UC (6)
- biochem
- imaging (2)
Stool test - elevated calprotectin
FBC - high WBC, high platelets
ESR - elevated
CRP - elevated
Flexible sigmoidoscopy
Colonoscopy + biopsy - DEFINITIVE
32
Treatment of UC (4 medical, 2 surgical)
Medication:
- 5ASA (aminosalicylates) - e.g. mesalazine, sulfasalazine
- immunosuppressants
- -----> steroids (prednisolone)
- -----> azathioprine*
- biologics (anti-TNFa antibodies - infliximab)**
Surgery
- proctocolectomy (rectum + colon removal) + permanent ileostomy (stoma) - most standard
- total colectomy + ileorectal anastomosis
*only used in refractory disease = if not responsive to normal treatment, i.e. 5ASA and steroids
**only used in refractory or severe disease
33
Pathological findings (i.e. if you were to look at it specimen physically) of UC (3)
Continuous pattern of inflammation
Inflamed RED granular mucosa
Pseudopolyps - projecting masses of scar tissue that have healed from ulceration (so old ulcer remnants)
34
Histological findings of UC (6)
Inflammatory infiltrates - high neutrophils
Mainly mucosal inflammation/ulcers + mucosal atrophy
CRYPT ABSCESSES/CRYPTITIS
NO GRANULOMAS
May get atypia (abnormal structure) of cells --> adenomatous change --> invasive cancer
35
Pathological findings (i.e. if you were to look at it physically) of Crohn's disease (4)
GRANULAR serosa/dull grey
Mesentery - thickened and fibrotic
THICK COLON WALL --> NARROW lumen
'Skip/cobblestone lesions' - bits of normal colon then abnormal colon
36
Histological findings of Crohn's (6)
NON-CASEATING GRANULOMAS
Cryptitis/ distortion of crypt cells
DEEP ulceration - TRANSMURAL inflammation
Fistula/stricture formation --> narrowing intestine
Fissuring ulcers
Lymphoid aggregates and neutrophil infiltrates
37
Is ulceration superficial/deep in UC vs crohn's
UC - superficial
| Crohn's - deep
38
What is crohn's disease
Disorder of unknown aetiology characterised by transmural inflammation (=all layers of bowel wall) of ANYWHERE in the GI) tract - from mouth to peri-anal area
39
Symptoms (3) /signs (4) of Crohn's disease
Abdo pain/cramp - RLQ
CHRONIC diarrhoea - not usually bloody
Fatigue
Peri-anal lesions - skin tags/fistula/abscess
Blood in stool - more so microscopic, NOT GROSS BLEED
Oral lesions/ulcers
Weight loss
40
Risk factors of Crohn's disease (3)
White
Age 15-40 or 60-80
Family history of crohn's
41
Extra-intestinal manifestations of IBD (4)
Eyes - irritated, red eyes, e.g. uveitis
Joints - arthritis
Skin - painful red patches, often on legs
Liver - primary sclerosis cholangitis (risk of cholangiocarcinoma)
42
Investigations of Crohn's disease (7) + which of these is the definitive diagnosis
- biochem (4)
- imaging (3)
FBC - low Hb, high WBCs
CRP
ESR
Stool test - elevated faecal calprotectin only significant in UC
AXR
Abdo CT
Colonoscopy + biopsy - definitive diagnosis
43
Treatment of Crohn's disease
- medical (6)
- surgery indicated if
5ASA (aminosalicylates) - e.g. mesalazine, sulfasalazine
Immunosuppressants
- Steroids (prednisolone/budesonide) - MORE USED
- azathioprine, methotrexate
Manage extra-intestinal manifestations - uveitis, arthritis,
Biologics (anti-TNFa antibodies - infliximab) -
Antibiotics - only if septic complications suspected
Surgery - if no improvement with medical therapies
44
Are antibiotics used for UC or crohn's
Crohn's
45
Complications of Crohn's disease (4)
Intestinal obstruction
Abscess formation
Fistulas
Extra-intestinal manifestations - uveitis, arthritis
46
Complications of UC (5)
```
Pseudopolyps
Toxic megacolon
Perforation
Stricture --> fistulas
Colonic adenocarcinoma
```
47
Are immunosuppressants such as azathioprine and biologics (anti-TNFa antibodies) such as infliximab used more in crohn's or UC
Crohn's
Only used in UC if refractory disease = if not responsive to normal treatment, or severe disease
48
Pathophysiology of acute appendicitis (4)
Obstruction of the lumen of the appendix usually by a calcified stone of faeces (faecolith) --> lumen distal to obstruction fills with mucus and swells --> increasing intraluminal pressure
Bacteria multiply rapidly and eventually leak out through the dying walls --> pus forms within and around appendix
49
Histological features of appendicitis (3)
Fibrinopurulent exudate - pus + fibrin rich substance
Abscess
Full thickness necrosis of wall
50
Risk factors of appendicitis (4)
Young adult
Smoking
Pre-existing infection spread to appendix
IBD
51
Symptoms (3) /signs (3) in acute appendicitis
Abdominal pain (starts in umbilical region then moves to right lower quadrant)
Nausea
Anorexia
FEVER
RLQ tenderness (McBurney's point)
Tachycardia
52
Investigations of appendicitis (2)
- bloods
- imaging
FBC - elevated leukocytes (WBCs)
CT abdo/pelvis
53
Treatment of appendicitis (3)
IV fluids
IV antibiotics
Appendectomy ASAP
+/- abscess drainage
54
Complications of appendicitis (3)
Perforation
Peritonitis
Appendicular abscess
55
What is dysplasia
Structural change of cells/ abnormal development of cells
56
How is dysplasia related to colon cancer
Dysplasia can lead to formation of adenomas
57
2 Types of dysplasia
Low grade or high grade
58
Colorectal carcinoma is usually what type of tumour
Adenocarcinoma
59
Risk factors of colorectal cancer (7)
Increasing age
APC mutation
Lynch syndrome (aka hereditary non-polyposis colorectal cancer (HNPCC))
IBD
Obesity
Family history of CRC
Previous history of colorectal adenoma or CRC
60
Colorectal cancers are more often in the colon or rectum
Colon
61
Symptoms (2) /signs (3) of colorectal cancer
Rectal bleeding - esp left sided CRC
Altered bowel habit - esp left sided CRC
Anaemia - esp right sided CRC
Rectal mass
Constitutional symptoms/signs - weight loss, anorexia - if advanced disease
62
Common clinical features of a left sided CRC (3)
Altered bowel habit - more frequent, loss stools
Rectal bleeding - fresh blood
Annular shaped colon - apple core lesion
63
Clinical features of a right sided CRC (3)
Tumour grows outwards like a polyp
ANAEMIA
Vague visceral pain
64
Investigations of colorectal cancer (3 - imaging)
+ staging investigations (4)
Colonoscopy + biopsy
Barium enema
CT colonography (virtual colonoscopy)
CT chest/abdo/pelvis
Pelvic MRI
Rectal endoscopic ultrasound - better than CT for T staging
PET scan
65
Are most CRCs sporadic or genetic
Sporadic
66
Where does colorectal cancer spread to commonly (3)
Liver
Lungs
Lymph nodes
67
Pathophysiology of CRC development (3)
High grade dysplasia of colonic/rectal epithelial cells --> adenomatous polyps --> carcinoma
68
Colorectal polyps are...
Pre-malignant adenomas
69
3 histological types of colorectal polyps
Tubular (majority)
Villous
Tubulovillous
70
What do sessile polyps look like
Flat, blend in with lining
71
What do pedunculate polyps look like
Raised growths
72
Treatment of colorectal cancer
- colon cancer (surgical (2) /non surgical candidate (1))
- rectal cancer (surgical (2) /non surgical candidate (1))
- may need removal of what organ with metastases
Colon cancer
- if surgical candidate: surgical resection + chemotherapy
- if non-surgical candidate: chemotherapy
Rectal cancer
- if surgical candidate: surgical resection +/- neoadjuvant RADIOTHERAPY*/CHEMORADIOTHERAPY
- if non-surgical candidate: chemotherapy
Partial hepatectomy if liver metastases
*radiotherapy for rectal cancer only
73
Is neoadjuvant radiotherapy used in rectal or colon cancer
Rectal
74
Staging systems used in colorectal cancer (2)
TNM
| Dukes
75
Name 2 inherited syndromes that can predispose you to colorectal cancer
FAP (Familial adenomatous polyposis)
HNPCC (hereditary non-polyposis colorectal cancer) aka Lynch syndrome
76
Explain the Dukes staging system (4)
Dukes A - limited to mucosa and submucosa
Dukes B - invades through muscularis externa
Dukes C - regional lymph nodes involved
Dukes D - distant metastases
77
Explain the TNM staging system
- T (3)
- N (3)
- M (2)
T1 - involves mucosa/submucosa
T2 - involves muscularis externa
T3 - involves serosa
N0 - no lymph node metastases
N1 - 1-3 local lymph nodes
N2 - 4+ local lymph nodes involved
M0 - no distant metastases
M1 - distant metastases
78
Name 2 screenings tests for CRC
Faecal occult blood test (FOBT)
Faecal immunochemical test (FIT)
79
How does Faecal occult blood test (FOBT) work - to screen for CRC
+ how frequently is it done in Scottish bowel screening programme
Faecal sample placed on guaiac paper and hydrogen peroxide applied which, in the presence of blood, gives a blue reaction product
Every 2 years in Scottish bowel screening programme
80
How does Faecal occult blood test (FOBT) work - to screen for CRC
Finds hidden blood in faeces
| Uses specific antibodies that recognise human haemoglobin
81
Faecal occult blood test has high ... but low ...
Specificity
Sensitivity
82
Screening programme for CRC in people with FAP
annual colonoscopy from age 10-12
83
Screening programme for CRC in people with HNPCC
from age 25, bi-annual colonoscopy
84
What mutation occurs in FAP
APC gene mutation
85
What mutation occurs in HNPCC
Mutation in DNA mismatch repair (MMR) genes
86
Screening programme for people with family history of CRC
5 yearly colonoscopy from age 50 if high moderate risk
87
Screening programme for CRC in people with IBD
colonoscopy 10 years post IBD diagnosis
88
Screening programme for people with previous history of CRC
5 yearly colonoscopy
89
Causes of small bowel/intestinal obstruction (7)
```
Adhesions/scar tissue post surgery
Inguinal hernia
Foreign bodies
Intussusception (when part of the intestine slides into an adjacent part of the intestine
Tumour
Appendicitis
Crohn's disease
```
90
Symptoms (3) /signs (2) of bowel obstruction
```
Failure to pass wind/stool
Abdo pain
Nausea
Vomiting
Abdo distension
```
91
Treatment of small bowel obstruction (5)
IV FLUIDS
NASOGASTRIC DECOMPRESSION - NG tube put in to decompress air/fluid
Analgesia
Anti-emetics
Correction of underlying cause, e.g. appendicitis, hernia, tumour
92
Causes of large bowel obstruction (3)
Colorectal tumour - 90%
Colonic volvulus - loop of intestine twists around itself
Stricture
93
Definitive treatment of large bowel obstruction (1)
+ acute treatment (6)
Surgery to correct the cause
Acute
- Supplemental oxygen
- IV fluids
- electrolyte imbalances should be corrected
- Blood transfusion/blood products may be required to correct anaemia or coagulopathy
- Nasogastric decompression - to decompress the air/fluid in the intestinal tract
- Pre-op antibiotics
94
Low risk features of rectal bleeding (3)
Temp symptoms <6wks
Anal symptoms
<40yrs age = watch and wait for 6 wks, if symptoms persist/deteriorate --> refer for LI imaging
95
High risk features of rectal bleeding (4)
Persistent change in bowel habit >6wks
Persistent bleeding WITHOUT anal symptoms
Rectal/abdominal mass
Unexplained iron deficiency anaemia
96
Other causes of small intestine malabsorption apart from coeliac disease + crohn's
Infection
- tropical sprue
- HIV
- giardia lamblia
97
Define a severe flare up of UC
>6 bowel movements a day with lots of rectal bleeding
