Gastrointestinal System Flashcards
In which part of the GI system is iron, folate and calcium absorbed?
Proximal small intestine
At which point of the GI system is B12 absorbed?
Terminal ileum
What are the two types of contrast studies performed during GI investigations?
- Barium enema
2. Gastrografin studies
When is doing a gastrografin better than a barium enema?
When there is a risk of perforation - so acute abdomen situations - where you don’t want barium in the peritoneal cavity
What is a lactose-hydrogen breath test commonly used for?
To determine lactose intolerance
What are the causes of malabsorption? (9)
- Coeliac disease
- Protein-losing enteropathy
- Whipple’s disease
- Bacterial overgrowth
- Short bowel syndrome
- Tropical sprue
- Crohn’s disease
- Lactose intolerance
- Chronic pancreatitis
What are the symptoms of malabsorption? (3)
- Diarrhoea
- Steatorrhoea
- Weight loss
What are the signs of malabsorption? (3)
- Anaemia
- Oedema
- Hypovitaminosis
What investigations should be carried out in suspected cases of malabsorption? (2)
- Bloods - FBC, U&Es, LFT, albumin, calcium, folate, B12, vitamin D, coagulation, coeliac serology, TFTs
- Imaging: OGD, sigmoidoscopy
What are the most common causes of acute pancreatitis? (2)
- Alcohol
2. Gallstones
What are the other causes of pancreatitis?
Gall stones Ethanol Trauma Steroids Mumps Autoimmune Scorpion bite Hypercalcaemia ERCP Drugs (e.g. thiazide diuretics)
How does acute pancreatitis present? (3)
- Severe epigastric pain (often radiates to the back)
- Nausea
- Vomiting
What are the signs of acute pancreatitis?
- Tachycardia
- Pyrexia
- Hypotension
- Abdominal tenderness
- Reduced bowel sounds (secondary to ileus)
- Grey-turners sign or Cullen’s sign
What investigations should be carried out when suspecting pancreatitis? (5)
- Bloods - FBC, U&Es, LFTs, serum amylase (>1000IU/ml)
- ABG
- USS
- CT
- MRCP (magnetic resonance cholangiopancreatography)
What is the treatment for acute pancreatitis? (6)
- Analgesia
- IV fluids
- O2
- Urinary catheter
- NJ feeding (to avoid pancreatic stimulation)
- ERCP if gallstone obstructing bile duct
What are the complications of acute pancreatitis? (5)
- Pseudocyst
- Abscess
- Adult respiratory distress syndrome
- Renal failure
- Chronic pancreatitis
What is the Ranson criteria for acute pancreatitis? (aka modified glasgow criteria)
PANCREAS P - P02 <60mmHg/7.9kPa A - age >55years N - neutrophils WBC>15 C - calcium >2mmol/L R - renal function urea >16mmol/L E - enzymes LDH >600iu/L, AST>200iu/L A - albumin <32g/L S - sugar: glucose>10mmol/L
three or more positive factors detected within 48 hours of onset suggest severe pancreatitis (refer to HDU/ITU)
What causes jaundice?
An excess of bilirubin
What are the different ways jaundice can be classified?
- Unconjugated or conjugated
2. Pre-hepatic/hepatic/post-hepatic
What are the causes of pre-hepatic unconjugated bilirubin jaundice? (5)
These are mainly due to haemolysis:
- Immune mediated haemolysis - blood transfusions, SLE
- DIC
- HELLP
- Sepsis
- Malaria
What is the hepatic cause of unconjugated bilirubin jaundice?
Gilbert’s syndrome - impaired conjugation
What are the hepatocellular dysfunction causes of conjugated bilirubin jaundice? (5)
Hepatocellular dysfunction:
- Infection - viral Hep B, C, EBV, CMV
- Toxins - alcohol, drugs - paracetamol overdose, antibiotics, TB medication, statins
- Neoplastic - HCC
- Metabolic - Wilson’s, haemochromatosis
- Autoimmune hepatitis
What are the common causes of cirrhosis? (3)
- Alcohol liver disease
- NAFLD
- Hep B and C
The causes of conjugated bilirubin jaundice can be categorised into what?
- Hepatocelular dysfunction
2. Impaired hepatic excretion
What are the impaired hepatic excretion causes of conjugated bilirubin jaundice? (7)
- Gallstones/biliary system stones
- Primary biliary cirrhosis
- Primary sclerosis cholangitis
- Pancreatic carcnoma
- Cholagiocarcinoma
- Heart failure
- Budd Chiari (occlusion of the hepatic vein)
What medications cause jaundice?
- Dapsone (anti-malarial) - causes haemolysis
- Paracetamol, TB drugs - isoniazid, pyrazinamine - cause hepatitis
- Flucloxacillin, co-amoxiclav, erythromycin, chlorpromazine, prochlorperazine - cholestasis
What is the normal level of bilirubin in the blood? (range)
3-17 umol/L
In someone with jaundice, with dark urine and pale stools, what type of jaundice dose this indicate?
Post-hepatic (obstructive) jaundice
What are the stigmata of chronic liver disease found on the hands? (5)
- Clubbing
- Liver flap
- Leuchonychia (hypoalbuminaemia)
- Dupytren’s contracture
- Palmar erythema (increase in oestrogen)
What are the stigmata of chronic liver disease found on the skin? (4)
- Jaundice
- Spider naevi (>5)
- Caput medusae
- Bruising
What is caput medusae?
Enlarged superficial epigastric veins due to portal hypertension
What are the abdominal stigmata seen in chronic liver disease? (3)
- Ascites
- Hepatomegaly
- Splenomegaly
What are the facial stigmata synonymous with chronic liver disease? (2)
- Jaundiced sclera
2. Bleeding gums (coagulopathy, decreased production of clotting factors)
Why in liver disease are levels of vitamin K low?
The liver synthesises bile aids and secretes them into the small intestine where they play a critical role in the absorption of vitamin K …so no bile acids = no vitamin K
The liver produces all clotting factors except what?
Von willibrand factor
In terms of LFTs, where is the problem if ALT is raised, and what about for ALPs?
ALT usually indicates hepatic cellular dysfunction whereas ALP is gall bladder - an obstructive picture
If there is a raised in ALP alongside a raised gamma-glutamyl transferase (GGT) what does this indicate?
That the problem is suggestive of biliary epithelial damage and bile flow obstruction. - it is highly suggestive of cholestasis
What are the causes of an isolated ALP raise without raised GGT? (4)
- Bony metastases/primary bone tumour
- Vitamin D deficiency
- Recent bone fractures
- Renal osteodystrophy
If LFTs are normal but a patient is jaundiced, what does this commonly indicate?
A pre-hepatic cause
What are the two most common causes of isolated jaundice?
- Gilberts syndrome
2. Haemolysis - check FBC
Where is albumin produced and what is its role?
Produced by the liver and helps to bind water, cations, fatty acids and bilirubin. It also plays a key role in maintaining oncotic pressure of blood
In LFT derangement of ALT and AST, which one is most raised in chronic liver disease?
ALT>AST in chronic liver disease
What are the causes of AST being more raised than ALT?
Cirrhosis and acute alcoholic hepatitis
What are all the things screened for in a non invasive liver screen (NILS)? (7)
- FBC, U&Es, INR, glucose, lipid profile, albumin
2 Viral screen (Hep B, C, CMV, EBV) - Autoimmune liver screen + immunoglobulins (e.g. ANA, anti DS-DNA, ANCA, IgG)
- Tumour markers - AFP - alpha fetoprotein
- Metabolic - haemochromatosis (iron studies, ferritin+iron), Wilsons (copper, serum ceruloplasmin), alpha-1-antitrypsin
- Toxins - paracetamol
- Imaging - USS
What is important to ask a patient who presents with jaundice or abnormal LFTs? (8)
- Blood transfusion history
- IVDU?
- Tattoos
- Sexual activity (Fitz-Hugh-Curtis)
- Travel history
- Alcohol use
- Family history
- Drug history
What is hereditary haemochromatosis? (7)
- Autosomal recessive
- Disorder of iron metabolism and absorption
- Deposits in joints, liver, heart, pancreas, skin, testicles
- Middle aged men (40-60)
- Signs and symptoms -
early: fatigue, arthralgia, erectile dysfunction
later: bronze/grey skin, decompensated liver disease, cardiomyopathy, diabetes - Tests, biopsy, genetic screening
- Management - venesection
What are the features of Wilson’s disease?
- Autosomal recessive
- Increased Cu absorption and decreased secretion
- Onset usually between 10-25 years
- Children: liver disease, young adults: neurological dysfunction
- Presents with: liver dysfunction - hepatitis and cirrhosis, neurological (basal ganglia degeneration, dysarthria, ataxia and chorea), eyes (Kayser Fleischer rings)
- Management: Penicillamine (copper chelator)
What causes autoimmune hepatitis?
Unknown aetiology - autoantibodies against hepatocytes surface antigens
Who is most affected by autoimmune hepatitis?
Young or middle aged women
What tests should be performed when investigating autoimmune hepatitis?
- IgG
- Type 1: ANA, ASMA
- Type 2: anti-liver kidney microsomal type 1 antibodies
- Type 3: SLA
What is the management of autoimmune hepatitis?
- Steroids
- Immunosuppressants - Azathioprine
- Transplant
What is primary biliary cholangitis?
A progressive autoimmune disease of the biliary system causing intrahepatic cholestasis, scarring, fibrosis and cirrhosis. It is caused by unknown environmental triggers and is thought to have a genetic predisposition.
What are the signs/symptoms of primary biliary cholangitis?
- Cholestatic jaundice
- Liver disease
- Liver failure
What is the M rule associated with PBC? (3)
- Middle aged women
- IgM
- AMA
What is primary sclerosing cholangitis?
Inflammation and fibrosis of intra- and extra- hepatic bile ducts - a biliary system disease of unknown cause
What are the signs/symptoms of PSC?
- Liver disease/failure
2. Ascending cholangitis
What are the risk factors or association with PSC? (2)
Male gender
IBD
What are you at increased risk of if you have PSC?
Colon + liver + gall bladder cancers - yearly colonoscopies are required
What investigations/tests are done in suspected PSC? (3)
- Autoantibodies - ANA, ANCA
- MRCP
- Biopsy
What are the indications for haemodialysis?
AEIOU Acid-base problems Electrolyte problems Intoxications Overload, fluid Uraemic symptoms
What are the differentials for rectal bleeding? (5)
- Anal fissures
- Haemorrhoids
- Crohns
- UC
- Rectal cancer
What are the features of anal fissures - how can it present? (3)
- Bright red blood which occurs post-defecation
- Constipation
- Painful
What are the features of haemorrhoids - how may the person present? (2)
- Bright red blood on toilet paper and in toilet bowel
2. Post defecation on toilet paper, not mixed in.
What are the features of Crohn’s? (7)
- Diarrhoea usually non-bloody
- If there is blood - can be mixed in
- Altered bowel habits
- Fissures can occur
- Weight loss
- Abdominal pain
- Mouth ulcers
What are the features of ulcerative colitis? (3)
- Blood mixed in with stool
- Diarrhoea
- Proctitis
- NO perianal disease
What are the features of someone presenting with rectal cancer? (2)
- Bright red blood
2. Weight loss
What investigations should be done for someone with rectal bleeding? (5)
- Bedside
1. Stool MC&S - need to exclude campylobacter, c.diff, salmonella, e.coli
2. Faecal calprotectin - Bloods
3. FBC, ESR, CRP, U&Es, LFTs, pANCA
-Imaging
4- AXR
5. Colonoscopy
What is faecal calprotectin?
Faecal calprotectin (or fecal calprotectin) is a biochemical measurement of the protein calprotectin in the stool. Elevated faecal calprotectin indicates the migration of neutrophils to the intestinal mucosa, which occurs during intestinal inflammation, including inflammation caused by inflammatory bowel disease (but not IBS).
What are the key features of ulcerative colitis - the course and areas of IBD and symptoms? (7)
- Relapsing and remitting
- Inflammation always starts at rectum and never spreads beyond ileocecal valve
- No inflammation beyond submucosa (doesn’t affect all three layers)
- Episodic or chronic blood diarrhoea
- Cramp abdominal pain LLQ
- Tenesmus
- Proctitis
What is backwash ileitis?
A reflux of colonic contents into the distal few centimetres of the ileum through the ileocaecal valve. …this can make the distinction between UC and CD more difficult
What are the extra-intestinal manifestations of UC? (4)
- MSK - arthritis (typically affecting sacroiliac and other large joints)
- Skin - erythema nodosum
- Eyes - episcleritis, anterior uveitis, or iritis
- Hepatobiliary - primary sclerosing cholangitis
What is the TRUELOVE and WITTS criteria?
It classifies UC into mild, moderate and severe episodes, dependent on the number of bowel motions, rectal bleeding and systemic features.
What is classed as mild UC?
<4 bowel motions per day with a small amount of blood and no systemic features
What is classed as moderate UC?
4-6 bowel motions, varying amounts of bleeding but no systemic features
What is classed as severe UC?
More than 6 bowel motions, bloody diarrhoea and systemic features e.g. tachycardia and/or pyrexia
What is the first line treatment for people with mild-moderate UC?
Topical aminosalicylates e.g. rectal mesalazine (if not response within 4 weeks, add an oral aminosalicylate, and no response again then steroid - topical or oral)
What is the treatment for moderate UC? (2)
- Rectal or oral aminosalicylates (increased dose compared to mild)
…if needed; - Oral prednisolone (then taper down)
What is the treatment for extensive UC? (2)
- Rectal and high dose oral aminosalicylates
…If needed; - No remission - oral aminosalicylates and oral steroids
What is the treatment for severe UC?
- IV steroids
- IV ciclosporin (if steroids aren’t effective after 72 hours OR if worsening despite steroid treatment)
3.
What is the recommendation with regards to oral aminosalicylates compared to topical?
If someone doesn’t want to use topical aminosalicylates they can have oral has first-line, however they must be informed it is not as effective
Which drugs will sometimes be given by a specialist in moderate-severely active UC?
Biologics and Janus kinase inhibitors
What is the top differential for a person with known UC presenting with severe abdominal pain, distention and pyrexia. With HR 120 and BP 90/60?
Toxic megacolon - where the deeper layer of the bowel becomes affected, with >6cm thumbprinting. Caused by anti-diarrhoeal agents and codeine. Decompression should be attempted.
In terms of distribution, how are UC and Crohn’s different?
Crohns affects anywhere mouth to anus whereas UC is the rectum and colon
In terms of depth, whats the difference between UC and Crohns?
Crohn’s is transmural whereas UC is superficial
What are the signs of Crohn’s disease? (3)
- RIF mass
- Perianal disease
- Extraintestinal same as UC
What are the recommended investigations for Crohn’s?
Same as for UC \+ Barium swallow \+ Additional bloods - B12 and albumin
Why is a barium swallow indicated for Crohns?
It will show strictures, gross mucosal changes and the presence of fistulas. It is also useful for showing the length of the bowel.
What are the complications of Crohn’s?
- Fistula
- Abscess
- Colorectal cancer
What is the treatment for mild Crohns?
- Corticosteroid
2. Add on = azathioprine or mercaptpurine
When is an add on indicated?
When the patient experiences two or more inflammatory exacerbations within a 12 month period
What needs to be checked before azathioprine or mercaptpurine are started and why?
TPMT - thiopurine methyltransferase - this is one of the enzymes involved in the metabolism of these drugs, and patients with low levels of this enzyme are at a risk of life-threatening bone marrow suppression
What is the treatment for severe Crohns disease?
IVI
IV hydration
IV steroids
Which drugs are used when a patient is in remission with Crohn’s?
- Azathioprine or mercaptpurine
2. Methotrexate (second line)
What are the signs/symptoms associated with a pharyngeal pouch?
Patients often complain of regurgitation of foul smelling liquid, halitosis is noted, episodic dysphagia.
Why is upper GI endoscopy potentially hazardous for people with a pharyngeal pouch?
Because there is a risk of perforation
What is Killians dehiscence?
It is a triangular area of weakness in the wall of the pharynx. It is where pharyngeal pouches are known to develop.
What is achalasia?
It is primarily a disorder of motility of the lower oesophageal sphincter. The smooth muscle layer of the oesophagus has impaired peristalsis and failure of the sphincter to relax causes fictional stenosis or functional oesophageal stricture. Most causes have no known underlying cause, but a small proportion occurs secondary to other conditions e.g. oesophageal cancer.
What controls the tone and activity of the muscles in the oesophagus?
The muscles are controlled by a balance of excitatory transmitters such as acetylcholine and substance P, and inhibitory transmitters such as nitric oxide and vasoactive intestinal peptide (VIP).
In addition to oesophageal cancer, what else is thought to contribute to the development of achalasia?
It is thought that it could be an autoimmune reaction to viral infections and additionally genetic factors.
What is the mean age of diagnosis of achalasia?
53
What is the most common presenting feature of achalasia?
Dysphagia
In addition to dysphagia, how else can achalasia present? (5)
- Regurgitation (occurs in 80-90%)
- Chest pain (often described as retrosternal and occurs after eating)
- Heartburn
- Weight loss (can suggest malignancy)
- Nocturnal cough (feature of later disease)
What can sometimes be seen on CXR for someone with achalasia?
Vastly dilated oesophagus behind the heart - however this is rarely seen in practice
Due to the risk of perforation of a malignancy, what tends to be done to investigate potential achalasia?
Barium swallow - this show the characteristic birds beak - the oesophagus is dilated and the contrast material slowly passes into the stomach as the sphincter opens intermittently. The image resembles a birds beak. This is in contrast to the rats tail appearance of carcinoma of the oesophagus.
In patients who are fit enough for surgery, what is the first-line treatment for achalasia?
Heller myotomy
A patient presents with multiple non-healing leg ulcers, feels generally unwell, and has pale conjunctivae, poor dentition and bleeding gums. What is the most likely cause?
Vitamin C deficiency -scurvy - leads to defective synthesis of collagen, resulting in capillary fragility (bleeding tendency) and poor wound healing
What are people with primary sclerosing cholangitis at risk ok?
Cholangiocarcinoma (10%)
Which IBD is more associated with primary sclerosing cholangitis?
Ulcerative colitis - 80% of patients with PSC have UC
What investigation is gold standard for PSC and what will it show?
MRCP - showing multiple biliary strictures giving a ‘beaded’ appearance
Which blood test may be positive for PSC?
ANCA
Which blood test may be positive for PBC?
Anti-mitochondrial antibody
What is the single stronger risk factor for developing Barrett’s oesophagus?
GORD
What is given to patients long-term if they have an episode of spontaneous bacterial peritonitis?
Ciprofloxacin
What is the most common cause of spontaneous bacterial peritonitis? - which organism if found of ascitic fluid culture?
E.coli
What is spontaneous bacterial peritonitis?
It is a form of peritonitis usually seen in patients with ascites secondary to liver cirrhosis - features include ascites, abdominal pain and fever.
What is the management for spontaneous bacterial peritonitis?
IV cefotaxime
What is hepatorenal syndrome?
It is a complication of end-stage liver disease, which occurs in patients who have chronic liver dysfunction with cirrhosis and ascites, and also in acute liver failure. In hepatorenal syndrome, there is impaired renal function which is often precipitated by events lowering blood pressure. The end result is intra-renal arteriolar vasoconstriction.
What is the criteria for the diagnosis of hepato-renal syndrome in cirrhosis?
- Cirrhosis with ascites
- Serum creatinine >1.5mg/dL
- Absence of shock
- Absence of hypovolaemia
- No current or recent treatment with nephrotoxic drugs
- Absence of parenchymal renal disease as defined by proteinuria <0.5g/day and normal renal USS