gastroenterology - final Flashcards
definition of IBS
an idipathic GI disorder characterised by chronic abdomial pain and altered bowel habits (diarrhoea and/or constipation)
- abnormal functioning of otherwise normal bowel
(usually linked to stress)
what are the subtypes of IBS
*IBS-C (IBS with predominant constipation) = > 25% motions are usually constipation (types 1 and 2) and <25% are types 6 and 7
*IBS-D (IBS with predominant diarrhoea) ) = > 25% motions are usually diarrhoea (type 6 and 7), <25% are types 1 and 2
*IBS-M (IBS with mixed bowel habits) ) = alternating diarrhoea and constipation, more than 25% types 1 and 2,AND more than 25% type 6 and 7
*IBS-U (IBS unclassified – can’t accurately classify into one of the 3 subtypes) – change in stool consistency is insufficient to categorise
what is the normal age range for a pt presenting with IBS
pts often present as teens or in their 20s
RFs for IBS?
- female gender
- younger age (20-40)
- PTSD
- physical and sexual abuse
- stress/anxiety
- Hx of mental health disorders (MDD)
- Hx of GI infections (post-infectious IBS) - gastroenteritis
- FHx of IBS
Associated conditions (can make IBS worse or IBS can make these conditions worse)
other functional disorders
- Comorbid psychiatric disease e.g. major depression (MDD)
- Fibromyalgia – associated with stress
- Chronic fatigue syndrome (CFS) - associated with stress
- GERD and functional dyspepsia
- Sexual dysfunction
- Premenstrual syndrome (PMS) – hormonal changes, can make Sx worse
- Somatisation (headache, joint pain)
Aetiology of IBS
cause = unknown, combination of factors, disorder of gut brain interaction - NO ORGANIC CAUSE
*abnormal gut motility - longer transit time
*alterations in gut microbiome (overgrowth of certain specied
*hypersensitivity to gut stimuli
* psychological factors: stress anxiety can influence expression of Sx
*food hypersensitivity (short chain carbs are metabolised by bacteria → gas and bloating)
signs of IBS
abdominal distension (gas)
mild abdominal tenderness
symptoms of IBS
mostly occur in the daytime and are relieved with defaecation
ABC: abdominal discomfort, bloating, change in bowel habits
- chronic abdo pain + discomfort (exacerbated with stress/meals/mensturation)
- bloating
- change in bowel habits: diarrhoea (non-bloody), constipation or a combo of both
- diarrhoea w/ mucous discharge
- tenesmus may be present (sensation of incomplete bowel emptying)
- nausea
- fatigue
Ix for IBS
Initial tests - rule out DDx
* FBC, ESR, CRP (inflammation)
* Coeliac testing (anti-TTG or anti-EMA)
* faecal calprotectin (IBD)
Note that the following tests are NOT required: abdominal ultrasound, sigmoidoscopy/colonoscopy, TFTs, FOBT, faecal ova and parasite test, hydrogen breath test.
describe how IBS is diagnosed
Rome IV criteria:
A positive Dx of IBS should be made if the pt has abdominal pain relieved by defaecation or associated with altered bowel frequency/stool form (appearance) in addition to 2 of the following 4 Sx:
* Altered stool passage (straining, urgency, incomplete evacuation)
* Abdominal bloating (more common in women than men), distension, tension or hardness
* Sx made worse by eating
* Passage of mucus
Some other features may support the diagnosis:
* Lethargy
* Nausea
* Backache
* Bladder symptoms
List some DDx of IBS
- IBD
- coeliac disease
- lactose intolerance
- food allergies
- GI infections
What are some complications of IBS
IBS doesn’t increase the risk of colon cancers
- Dehydration
- Electrolyte imbalance
- Bowel impaction
- Haemorrhoids – due to bowel habit changes
- Anxiety/depression – IBS can increase risk
What red flag Sx should be ruled out before a Dx of IBS
- Rectal bleeding
- Unexplained/unintentional weight loss: > 10% in 3 months
- FHx of bowel/ovarian cancer
- Onset after 60 years of age – change in bowel habits is worrying in this group of pts
- Palpable abdominal mass
- Nocturnal diarrhoea (night time Sx - IBS Sx are usually during the day)
- Fever
- Anaemia
- Lab abnormalities
Management of IBS
1st line = lifestyle and dietary advice
o Stress management (exercise/meditation)
o Regular meals
o Reducing alcohol/caffeine (max 3 cups)
o Increasing soluble fibre (Ispaghula powder – if constipated) and reducing insoluble fibre (bran)
o Probiotics (trial for 4 weeks)
o if unsuccessful –> dietician review –> e.g. low FODMAP diet (apples, cherries, peaches, lactose, legumes, green veg)
o Regular meals, good hydration (8 cups per day).
2nd line = medications
o Pain: Antispasmodics (Mebeverine, Buscopan)
o Constipation: Laxatives e.g. Isphagula husk (avoid lactulose due to bloating) → Linaclotide (only if max tolerated dose of previous med doesn’t work AND they have had constipation for at least 12 months) → Prucalopride (when all other laxatives fail)
o Diarrhoea: Loperamide (Imodium)
if still no better
* TCAs - warn about drowsiness, takes 4-6 weeks to have an effect
* if TCAs not tolerated, move on to SSRIs
3rd line = psychological therapy
o CBT
o Hypnotherapy
What are the different types of stool according to the bristol stool chart
type 1: hard lumps like nuts (constipation)
type 2: sasuage shaped lumpy
type 3: sausaged shaped with cracks at surface
type 4: sausage shaped (normal)
type 5: soft blobs with clear cut edges
type 6: fluffy and mushy with ragged edges
type 7: watery, entirely liquid (diarrhoea)
- the higher the number the higher the water content of the stool
definition of constipation
- passing stool < 3 times per week
- hard/lumpy/dry stool
- difficulty of passage: excessive straining/tenesmus (sense of incomplete evacuation)
pathophysiology of constipation
- reduced colonic motility - motility is needed to propel stool through colon to rectum
- impaired rectal sensation and function - normally rectum senses presence of faecal matter and urge to defaecate
- defaecation disorders - pelvic floor dysfunction (inability to relax anal sphincter)
- psychological factors - stress, anxiety, and depression, can alter the functioning of the GI tract
RFs for constipation
- elderly (age > 65)
- female sex
- lower socioeconomic status
- african ancestry
- toileting habits - rushing, witholding
common causes of constipation
- inadequate fibre/fluid intake
- immobility
- IBS - may alternate with diarrhoea
- post-op pain
- hospital environment - lack of privary and using bedpan
- elderly (age)
causes of constipation: bowel disease
- colorectal carcinoma
- anal fissures - pain can cause reluctance to defaecate
- anal stricture
- rectal prolapse
- pelvic mass (foetus - pregnancy, fibroids)
- bowel obstruction
causes of constipation: metabolic/endocrine
- hypothyroidism - reduced metabolism
- hypercalcemia
- hypokalaemia
causes of constipation: medications
- opioid analgesics: morphine, codeine
- anticholnergics: TCAs (Amitryptyline)
- iron tablets
- CCBs
causes of constipation: neurological
- diabetic neuropathy
- Parkinson’s
- spinal cord lesion
- depression (especially in pts who somatise more)
Ix for constipation
- DRE: check anal sphincter tone and presence of faecal matter
- bloods: FBC, TFTs (hypo), Ca (hyper), U&E
- abdo x-ray: if secondary cause of constipation is suggested
- barium enema: if suspected impaction or mass
- colonoscopy: if suspicion of lower GI malignancy
management of constipation
treat underlying pathology - treatment depends on cause
- lifestyle modifications: increase fibre (wholemeal carbs, bran, fruits)
- more exercise - keep mobile
ONLY give medication if the above doesn’t work
- enemas if impaction
- suppository e.g. glycerol
- bulk-forming laxatives e.g. isphagula, methylcellulose (increase faecal mass to promote peristalsis)
- osmotic laxatives e.g. lactulose (retain fluid in bowel)
- stool softeners e.g docusate sodium
- stimulant laxatives e.g. senna
complications of constipation
- haemorrhoids (swollen and inflammed veins due to straining)
- anal fissures (tears in the skin of the anus)
- faecal impaction (hard stools that won’t pass as rectum is stretched out leading to muscle dysfunction)
- overflow diarrhoea (faeces above blockage may travel around it and out the anus)
- acute urinary retention (impacted stool may press on bladder)
red flags for constipation
the following may indicate GI malignancy:
* sudden weight loss
* dark stools
* abdominal mass
* loss of appetite
* recal bleeding
definition of coeliac disease
Autoimmune condition where exposure to gluten causes inflammation in the small bowel.
Gluten is a protein found in wheat, rye and barley
epidemiology of coeliac disease (age, ethnicity)
bimodal peak incidence for age but can present at any age
* 1-3yrs when first exposed to gluten in diet (e.g. cereal)
* adults 50-60
more common in irish ancestry
RFs for coeliac disease
- FHx of coeliac disease: First degree relatives (parents/siblings/children) with coeliac disease
- Autoimmunity
- Genetic predisposition - 95% of patients have HLA-DQ2 allele, and 80% have HLA-DQ8 allele
- IgA deficiency: allows increased gluten peptides to circulate in the submucosa
- Down’s syndrome
- Turner’s syndrome
- William’s syndrome
what conditions are associated with coeliac disease
other autoimmune conditions
- T1DM - all new cases of T1DM are tested for coeliac disease even if they don’t have Sx as the conditions are linked
- autoimmune thyroid disease: Grave’s, Hashimoto’s
- autoimmune hepatitis
- PBC (primary biliary cirrhosis)
- PSC (primary sclerosing cholangitis)
what skin condition is associated with coeliac disease
dermatitis herpetiformis = red vesicular, blistering pruritic (itchy) red eruptions
locations: extensor surfaces (shoulders, elbows, knees), trunk, scalp
cause: IgA deposits (anti-epidermal transglutaminase) in epidermis
what is the most common type of pancreatic cancer and where is it typically located
pancreatic adenocarcinomas are most common and are found in the head of the pancreas (80%)
cancer of the epithelial cells that have a gland-like appearance under microscopy
prognosis of pancreatic cancer
poor as disease is usually advanced at time of diagnosis
symptoms of pancreatic cancer
- painless (obstructive) jaundice: pruritus (generalised itching), yellowing of sclera + skin, pale stools, dark urine
- this happens as tumours of the head of the pancreas compress the common bile duct
- epigastric pain radiating to the back
- anorexia and weight loss (due to malignancy/malabsorption)
- steatorrhoea (foul smelling, fatty stool, difficult to flush)
- N + V 🤮
- faitgue
signs of pancreatic cancer
- Courvosier’s sign: painless palpation of gallbladder with jaundice = unlikely to be a gallstone and is likely to be pancreatic Ca/ cholangiocarcinoma
- Trousseau’s sign = migratory thrombophlebitis - small blood clots in the superficial veins, that are associated with inflammation (feel like small bumps under skin)
- worsening of T2DM (or new onset in elderly) - due to loss of endocrine function- presentation of the tumour in the body/tail (presentation: thirst, polyuria, nocturia, weight loss)
where does pancreatic cancer metastasise to
first metastasises to the LYMPH NODES (including Virchow’s node):
* peritoneum
* LIVER (via portal vein) - ascites
* LUNGS
* BRAIN
* bowels - constipation
what are the primary Ix for pancreatic cancer
- LFTs: likely to show an obstructive picture with raised ALP, GGT and bilirubin
- coagulation profile: to assess synthetic function of liver to determine possibility of metastasis
- abdominal USS: part of initial work-up (pts with jaundice)
- HRCT of pancreas (gold standard - Ix of choice): for diagnosis + biopsy (for histology)
- Biopsy can be done: percutaneously (USS/CT) or EUS (endoscopy with US guidance)
- CA-19-9 (tumour marker) - used to monitor disease but is NOT diagnostic
what are the RFs for pancreatic Ca
main RF: smoking
alcohol only indirectly increases risk
non-modifiable RFs:
* FHx (genes) e.g. BRCA2
* age (60+)
* male
modifiable RFs:
* smoking
* obesity
* diet high in fat
associated conditions:
* liver cirrhosis
* chronic pancreatitis
* T2DM
* MEN (multiple endocrine neoplasia)
management of pancreatic Ca
surgical resection (to remove tumour - only hope for cure)
* distal pancreatectomy (tumour of tail)
* whipple’s procedure (pancreaticoduodenectomy) = removal of pylorus of stomach, head of pancreas, common bile duct, gallbladder, proximal duodenum and relevant lymph nodes
* modified whipple’s ‘PPPD’ = pylorus sparing
chemo: adjuvant or neoadjuvant
palliative care:
* stenting via ERCP to relieve obstruction of bile duct
* palliative chemo
* palliative radiotherapy
* surgery to bypass biliary obstruction
pancreatic enzyme replacement
describe the referral criteria for pancreatic cancer
urgent referral (2WW to be seen in a clinic) if > 40 with jaundice
referral for direct access CT abdo ( to be done within 2 weeks) = over 60 with weight loss and one of:
* nausea
* vomiting
* back pain
* abdo pain
* constipation
* new onset diabetes
describe the typical presentation of pancreatic cancer
pt ages 65-75 with painless obstructive jaundice and weight loss
what are some of the Ix to consider in pts with pancreatic cancer
done if CT is inconclusive:
* PET-CT: for staging if disease is localised and pt is having treatment
* EUS: allows FNA and can identify small tumours
* ERCP: allows for biliary drainage and biopsy, can be used to insert stent to relieve Sx
imaging may demostrate ‘double duct’ sign due to simultaneous dilation of the pancreatic and common bile ducts
what are the cancer-related complications of pancreatic cancer
- VTE: pancreatic adenocarcinoma is thrombogenic
- new-onset diabetes mellitus: loss of endocrine function due to cancer growth + surgical resection
- cholangitis: obstruction of biliary tree increases risk of infection
what are the surgery-related symptoms of pancreatic cancer
DUMPING SYNDROME = when sugar moves too quickly into the small intestine
- early dumping syndrome (30 mins after a meal): fluid moves into intestine due to high osmotic load → DIZZINESS AND PALPITATIONS
- late dumping syndrome (2 hours after meal): as glucose is rapidly absorbed in the intestine → reactive hyperinsulinamiea and subsequent hypoglycaemia
PEPTIC ULCER DISEASE
what is a Mallory Weiss Tear
a longitudinal tear in the muscosa of the oesophagus at the GOJ due to a rapid increase in intra-abdominal pressure (leading to bleeding from submucosal arterial/venous plexus)
aetiology and RFs for Mallory Weiss syndrome
- male
- age: 40-60
- conditions that cause vomiting: hyperemesis gravidarum, bulimia, gastroenteritis
- chronic cough: COPD, asthma, bronchiectasis
- alcohol: binge drinking, damages mucosa and causes vomiting
- hiatus hernia
- GORD
what are the DDx for Mallory Weiss syndrome
- reflux oesophagitis: irregularly shaped ulcerations would be seen
- Boerhaave syndrome = transmural oesophageal tear
clinical features of Mallory Weiss tear
- haematemesis
- epigastric pain/back pain
- malaena
- shock (hypovolemic): postural hypotension, tachycardia, drop in BP, dizziness
what are the Ix for Mallory Weiss syndrome
- FBC (anaemia)
- U&E (raised urea as RBCs are digested into urea)
- LFTs (to check for liver disease, usually NORMAL - if deranged may suggest a variceal bleed)
- coagulation studies (prothrombin time etc) - to look for coaugulopathies and thrombocytopenia
- cardiac workup (to look for myocardial ischaemia): ECG, troponins, creatine kinase
what is the diagnostic Ix for Mallory Weiss syndrome and what does it show
upper GI endoscopy - should be done in ALL pts once they’re stabilised (after resus)
a single longitudinal tear that appears as a red break in the mucosa
describe the management of Mallory Weiss syndrome
most tears self-resolve
main Rx:
* resuscitation to stabilise pt (fluid resus and blood replacement)
* diagnostic and therapeutic endoscopy (for definitive management)
* manage precipitating and exacerbating factors: PPI, antiemetics
* monitor for complictions: ECG for myocardial ischaemia
1) ABC
* fluid resus: IV fluids
* blood transfusion, blood products
anti-emetics is pt is vomiting e.g. ondansetron
2) endoscopy +/- adrenaline injection (vasoconstriction)
* thermocoagulation
* band ligation/haemoclip (mechanical compression)
3) PPI - given post endoscopy (otherwise it can mask bleeding)
* protecting stomach acid from causing further damage to mucosa
4) surgery - if endoscopic therapy isn’t successful = arterial embolisation (angiotherapy) - left gastric artery is blocked (to prevent blood flow to its oesophageal branches so bleeding is prevented)
5) lifestyle changes
* reduce alcohol consumption
* CBT for bulimia
what are the complications of mallory weiss tear
- rebleeding - lacerations can bleed again (usually occurs within 24hrs)
- hypovolemic shock
- oesophageal perforation
- myocardial ischaemia
what are the scoring systems for upper GI bleeds
1) Glasgow-Blatchford score (GBS) - done to risk stratify pts before endoscopy
* score of 0: pt can be dishcharged, outpatient endoscopy can be arranged for a later time
* score > 0 = pt is admitted and inpatient endoscopy is done within 24 hours
* score based on: urea, Hb, HF, intial SBP, gender, tachycardia (HR), melaena, Hx of syncope, hepatic disease Hx
2) Rockall score - done after endoscopic treatment to assess risk of adverse outcomes
* based on: age, BP, comorbities, endoscopic findings
what are oesophageal varices
dilated veins of the oesophageal submucosa at the junction between portal circ and systemic venous system- these veins are not used to holding high pressure blood and therefore are prone to rupture which can cause heaving bleeding
rupture of oesophageal varices is life-threatening and comes with a high risk of mortality
what causes oesophageal varcies
caused by portal hypertension (mainly secondary to liver cirrhosis - commonly from alcoholism) → blood is shunted to other routes
main shunt: portal vein → left gastric vein → oesophageal veins (become distended and tortuous)→ azygous vein → back to heart
what is the diagnostic Ix for oesophageal varices
GOLD STANDARD = OGD (oesophagogastroduodenoscopy) ‘
aka: upper GI endoscopy’
what is the management of an acute oesopheageal variceal bleed
- ABC: IV fluids
- blood transfusion - for massive blood loss
- correct coagulopathy: vitamin K, FPP, platelet infusions
- Terlipressin (ADH analogue): causes splanchnic vasoconstriction which reduced portal pressure
- Broad spectrum Abx: reduce mortality by reducing risk of bacteraemia and spontaneous bacterial peritonitis
Once patients have been haemodynamically resuscitated is important to arrange urgent endoscopy, ideally within 24 hours.
* At endoscopy, variceal band ligation is the treatment of choice.
* Balloon tamponade: If bleeding is uncontrollable, a Sengstaken-Blakemore tube may be inserted as a temporary measure to tamponade the bleeding varices
For patients with a history of alcoholism, thiamine may be required to correct any deficiency.
If there is refractory bleeding: TIPS may be needed (Transhepatic, Intrahepatic, Portosystemic Shunt) - metal stent is inserted to connect the portal vein to the hepatic vein which reduced portal vein pressure - potential complication = hepatic encephalopathy (as well as nutrients, toxins like ammonia can enter the liver faster)
For patients with a history of alcoholism, thiamine may be required to correct any deficiency.
what is the prophylaxis for oesophageal varices
- beta-blockers (non-selective) e.g. Propanolol - to reduce portal pressure (by causing splanchnic vasoconstrition - vasoconstriction of GI organs reducing blood flow to portal vein)
and/or - endoscopic band ligation = putting rubber band around varices
- screening endoscopy for pts with cirrhosis
what is Barrett’s oesophagus
metaplasia of the cells of the lower oesophageal muscosa from squamous epithelial cells to columnar epithelial cells w/ goblet cells
this new columnar epithelium is similar to that of the stomach/intestine, better at handling HCl and goblet cells release mucous to counteract the acid
happens due to long-standing GORD and chronic inflammation
what are the RFs for Barrett’s oesophagus
- GORD (single strongest RF) - oesophageal lining is damaged, over time epithelium erodes which promotes inflammatory cells that cause necrosis. This chronic damage leads to replacement of normal squamous epithelium with columnar epithelium
- smoking
- truncal (central) obesity and hiatus hernia: both of these lower the tone of the lower oesophageal sphincter which makes it easier for acid reflux to happen
- smoking
- male (7:1 ratio)
what cancer does Barrett’s oesophagus increase the risk of
Oesophageal adenocarcinoma
metaplasia to columnar epithelium → dysplasia of glandular cells = adenocarcinoma
describe the management of Barrett’s oesophagus
- high-dose PPI
- OGD + biopsy - for pts with metaplasia (and no dyplasia), endoscopy is recommended every 3-5yrs
- if dysplasia is identified - endoscopy is recommended - 2 options
1) radiofrequency ablastion (1st line)
2) endoscopic mucosal resection - lifestyle: smoking cessation, small regular meals, no hot drinks/alcohol/eating < 3 hrs before bed, avoid tight clothing
what are the symptoms of Barret’s oesophagus
Barrett’s oesophagus itself is asymptomatic but will have the symptoms of the coexistent GORD:
* pyrosis (heartburn) - worse with eating, lying flat at night, wearing tight clothing
* dyspepsia
* dysphagia
* dysphonia (hoareseness)
* belching
* cough
describe the pathophysiology of coeliac disease
- gliadin (part of gluten) is deaminated during digestion by tTG (tissue transglutaminase) → a complex is formed composing of tTG and gliadin
- coeliac disease = an autoimmune response to this complex which causes intestinal damage
- in pts with coeliac disease the deaminated peptides are presented to APCs via the molecules HLA-DQ2/DQ8 to T helper cells which triggers an immune response
- immune activation leads to: villous atrophy (therefore malabsorption), lymphocyte accumulation, intestinal crypt hyperplasia (due to mucosal damage)
clinical features of coeliac disease (GI/extra-intestinal)
Sx arise due to MALABSORPTION of nutrients
GI
* diarrhoea
* bloating
* N+V
* steatorrhoea
* abdo pain/discomfort
* weight loss (unexpected)
* constipation
other:
* anaemia (secondary to iron/folate/B12) deficient - fatigue ‘tired all the time’ + pallor
* osteoporosis (vit D and Ca malabsorption) → fractures
* bruising (vit K deficiency)
* mouth ulcers + angular stomatitis
neurological (rare)
* non-hereditary cerebellar ataxia
* idiopathic peripheral neuropathy
* epilepsy (seizures due to poor absorption of folate)