Gastroenterology Flashcards
Coeliac UK recommends that everyone with coeliac disease is vaccinated against pneumococcal infection and has a booster every 5 years
Due to hyposplenism
According to UK guidelines, long-term prophylaxis with oral ciprofloxacin (or norfloxacin) should be considered for patients at high risk for SBP, such as those with
a previous episode of SBP or
low ascitic fluid protein concentration.
SBP - G negative organisms
Most common,
Escherichia coli and Klebsiella pneumoniae.
Doxy - hepatotoxic- liver disease - danger
Diagnosis of SBP
Diagnosis
paracentesis: neutrophil count > 250 cells/ul
the most common organism found on ascitic fluid culture is E. coli
Antibiotic prophylaxis should be given to patients with ascites if:
patients who have had an episode of SBP
patients with fluid protein <15 g/l and either Child-Pugh score of at least 9 or hepatorenal syndrome
NICE recommend: ‘Offer prophylactic oral ciprofloxacin or norfloxacin for people with cirrhosis and ascites with an ascitic protein of 15 g/litre or less until the ascites has resolved’
Hepatitis B and vertical transmission
• babies born to mothers who are chronically infected with hepatitis B or to mothers who’ve had acute hepatitis B during pregnancy should receive a complete course of vaccination + hepatitis B immunoglobulin
pseudoachalasia
Whilst dysphagia of solids and liquids is a classic history for achalasia, certain features such as significant weight loss are not consistent and suggest cancer - ‘pseudoachalasia’
new-onset dysphagia is a red flag symptom that requires urgent endoscopy, regardless of age or other symptoms.
characteristically presents with right upper quadrant pain associated with refractor ascites.
Budd-Chiari syndrome
typically presents in teenagers or people in their twenties with neurological symptoms followed by liver failure
Wilson’s disease
Hydrogen breath testing is
an appropriate first line test for diagnosis of small bowel overgrowth syndrome
PRIMARY BILIARY CHOLANGITIS/CIRRHOSIS
(female:male ratio of 9:1)
This substantial increase in risk is primarily due to the chronic inflammation, fibrosis, and subsequent cirrhotic changes that occur in the liver parenchyma over time. The development of cirrhosis, regardless of aetiology, is a major risk factor for HCC, and PBC-related cirrhosis carries this markedly elevated risk.
It is important for clinicians to recognise this markedly elevated risk of HCC in patients with PBC who develop cirrhosis, as it informs the need for regular surveillance with ultrasound and serum alpha-fetoprotein measurements, typically performed every six months, to detect HCC at an early, potentially curable stage.
PBC Associations
Associations
Sjogren’s syndrome (seen in up to 80% of patients)
rheumatoid arthritis
systemic sclerosis
thyroid disease
Coeliac - duodenal biopsy
Duodenal biopsy from a patient with coeliac disease. Flat mucosa with hyperplastic crypts and dense cellular infiltrate in the lamina propria. Increased number of intraepithelial lymphocytes and vacuolated superficial epithelial cell vacuolated superficial epithelial cells. Higher magnification image on the right.
ZE syndrome
This patient who presents with refractory dyspepsia, diarrhoea, multiple duodenal ulcerations and CT evidence of a possible primary malignancy is likely to have Zollinger-Ellinson syndrome caused by a gastrin-secreting tumour (gastrinoma).
The multiple duodenal ulcers are caused by increased acid secretion by gastric parietal cells as a consequence of hypergastrinemia. Levels of serum gastrin, if measured, will be very elevated. It is sometimes associated with multiple endocrine neoplasia (type 1) but normal levels of PTH, calcium and prolactin make this unlikely in this case.
are all hormones that inhibit H+ secretion among their other effects and are therefore not the likely cause of numerous duodenal ulcers.
Secretin, somatostatin and vasoactive intestinal peptide
**** does not stimulate or inhibit acid secretion but rather causes the release of digestive enzymes from the pancreas and contraction of the gallbladder.
Cholecystokinin
Patients with FAP are also at risk from duodenal tumours. A variant of FAP called *** can also feature osteomas of the skull and mandible, retinal pigmentation, thyroid carcinoma and epidermoid cysts on the skin
Gardner’s syndrome
PBC v/s PSC
PSC affects both small and large bile ducts and has no specific diagnostic antibody.
Heamochromatosis
Ferritin and transferrin saturation are used to monitor treatment in haemochromatosis
SBP most common organisms
The most common causative organisms of SBP are gram-negative enteric bacteria. E coli is by far the most common followed by Klebsiella. The most common gram-positive organism causing SBP is Streptococcus pneumoniae followed by Streptococcus viridans and Staphylococcus.
Typically only one single organism is involved in the development of SBP. Prophylactic antibiotics (cephalosporins and quinolones) should be given to patients who have ascites and meet certain criteria.
What hormones does these cells secrete
Chief cells
D cells
G cells
Goblet cells secrete.
Chief cells secrete pepsin, a proteolytic enzyme.
D cells in the pancreas & stomach secrete somatostatin hormone.
G cells in the antrum of the stomach secrete gastrin hormone in response to distension of the stomach and vagal stimulation.
Goblet cells secrete an alkaline mucus that protects the epithelium against shear stress and acid.
Dieulafoy lesion
Often no prodromal features prior to haematemesis and melena, but this arteriovenous malformation may produce quite a considerable haemorrhage and may be difficult to detect endoscopically
Hepatic carcinoid
right heart valvular stenosis (left heart can be affected in bronchial carcinoid)
Chronic anal fissure Rx after laxatives and diet
Chronic anal fissure - topical glyceryl trinitrate
ANAL Fissure
around 90% of anal fissures occur on the posterior midline.
if the fissures are found in alternative locations then other underlying causes should be considered e.g. Crohn’s disease
Colonoscopy and cancer chances with polyps
At colonoscopy, approximately:
5 out of 10 patients will have a normal exam
4 out of 10 patients will be found to have polyps which may be removed due to their premalignant potential
1 out of 10 patients will be found to have cancer
Hepatitis B serology
previous immunisation: anti-HBs positive, all others negative
previous hepatitis B (> 6 months ago), not a carrier: anti-HBc positive, HBsAg negative
previous hepatitis B, now a carrier: anti-HBc positive, HBsAg positive
*** is given in cases of upper GI bleed caused by oesophageal varices rather than for peptic ulcers. Terlipressin acts by causing constriction of the splanchnic blood vessels, thereby reducing blood flow to the portal vein and decreasing pressure in the portal vein and the varices.
IV terlipressin
Perianal itching in children, possibly affecting other family members
→ Enterobius vermicularis (threadworms)
***** is transmitted via ingestion of infectious eggs similar to Enterobius vermicularis; however, it does not cause perianal itching. Clinical manifestations are variable and can include visceral larva migrans and ocular complications such as retinal granulomas. The treatment of choice is diethylcarbamazine.
Ascaris lumbricoides, also referred to as giant roundworm,
** occurs through the ingestion of ova present in canine faeces. This zoonosis is more frequently encountered in individuals with close contact with dogs that have consumed hydatid cysts from infected sheep, such as farmers. Clinical presentation diverges from that described in our case study by typically involving hepatic cyst formation and potential anaphylactic reactions if these cysts rupture.
Echinococcus granulosus transmission
****, is acquired through the consumption of undercooked pork containing larval cysts., it leads to conditions such as cysticercosis and neurocysticercosis, which can result in symptoms including headaches and seizures.
Taenia solium, or pork tapeworm
***** contracted by ingesting raw or undercooked pork products, characteristically presents with a clinical picture: fever, periorbital oedema, and myositis are common features. Management includes treatment with either mebendazole or albendazole.
Trichinella spiralis,
Cholestasis
drugs which may also cause cholestasis include antibiotics such as
COCP
co-amoxiclav, phenothiazines, sulphonylureas, fibrates and anabolic steroids.
Proton pump inhibitors
Proton pump inhibitors (PPI) cause irreversible blockade of H+/K+ ATPase of the gastric parietal cell.
Adverse effects
hyponatraemia, hypomagnasaemia
osteoporosis → increased risk of fractures
microscopic colitis
increased risk of C. difficile infections
Gastric distension (stretching of the stomach wall) actually stimulates gastrin secretion rather than inhibiting it.
This is part of the normal physiological response to food intake. When food enters the stomach causing distension, gastrin secretion increases to promote acid secretion and gastric motility, facilitating digestion.
APC gene is located in
Chromosome 5
This causes a hepatocellular pattern of drug-induced liver injury (DILI) where ALT > ALP.
Alcohol
Nitrofurantoin
Paracetamol
Atorvostatim
Alcohol liver disease
this is suspected, the AST level can be checked. The normal AST/ALT ratio is approximately 0.8. An AST/ALT ratio of 2.0 or higher suggests alcohol-related liver disease
The dysphagia characterised by difficulty initiating swallowing, nasal regurgitation, coughing, frequent aspirations, and associated dysarthria and drooling.
Bulbar palsy
dysphagia, regurgitation, cough and halitosis
Pharyngeal pouch
*** infects hosts via the worm penetrating the skin and therefore infections are more common in countries where people walk barefoot over land/soil.They attach and lay their eggs within the human jejunum. These eggs are passed into the stool and so the worms are not typically seen within the stool and very rarely around the anus. Also itching around the anus is not associated with this form of infection as the worm does not migrate to the area. Symptoms more commonly include abdominal pain, diarrhoea, weight loss and fatigue.
Ancylostoma duodenale
***** jejunal biopsy shows deposition of macrophages containing Periodic acid-Schiff (PAS) granules
Whipple’s disease:
it can cause a cobblestone appearance due to transmural inflammation and can affect any part of the gastrointestinal tract from mouth to anus.
Crohns disease
endoscopic findings might include segmental areas of pallor or necrosis reflecting inadequate blood supply.
Ischemic colitis
C diff causing antibiotics
Clindamycin and. 3 rd gen cephalosporins
Microscopic colitis
IBS
*** is a disorder of pigmentation of the bowel wall. Histology demonstrates pigment-laden macrophages.
It is associated with laxative abuse, especially anthraquinone compounds such as senna
Melanosis coli
thumbprinting’ may be seen on abdominal x-ray due to mucosal oedema/haemorrhage
Ischemic colitis
**** is a monoclonal antibody which targets C. difficile toxin B
Bezlotoxumab
Acute UGI bleed varices
prophylactic IV antibiotics
have been shown to reduce mortality in patients with liver cirrhosis
quinolones are typically used
NICE support this in their 2016 guidelines: ‘Offer prophylactic intravenous antibiotics for people with cirrhosis who have upper gastrointestinal bleeding.’
TIPS
Transjugular Intrahepatic Portosystemic Shunt is the correct answer. This procedure is the recommended treatment for a variceal haemorrhage uncontrolled with endoscopy. The hepatic vein is cannulated percutaneously via the internal jugular vein, using a needle under radiological guidance. A connection is created and a stent is inserted through the liver from the hepatic to the portal vein, thereby reducing portal pressure and reducing the risk of a bleed.
Encephalopathy is found in up to 25% of cases as blood normally detoxified in the liver, now bypasses this stage and toxins are delivered in greater quantity to the cerebral circulation.
T2DM with abnormal LFTs - ? non-alcoholic fatty liver disease
T1DM is not a/w NASH
A 31-year-old man is referred to gastroenterology with dysphagia. He feels that food is getting stuck in his oesophagus when he tries to swallow. His weight is static. He also complains of some heartburn with some improvement with omeprazole prescribed by his GP.
He has a past medical history of asthma, eczema and coeliac disease.
An oesophagus-gastro-endoscopy is performed which shows oesophagitis. Biopsies show an increased number of eosinophils.
Eosinophilic oesophagitis
Eosionophilic eosophagitis endoscopy
Endoscopy: diagnosis can only be made on the histological analysis of an oesophageal biopsy. There must be more than 15 eosinophils per high power microscopy field to diagnose the condition. Other findings on endoscopy include reduced vasculature, thick mucosa, mucosal furrows, strictures and laryngeal oedema. Histologically, the diagnosis is made more likely in the presence of epithelial desquamation, eosinophilic microabscesses, and abnormally long papillae
**** hyperchloremic metabolic acidosis with associated hypokalaemia because they produce large volumes of potassium, bicarbonate-rich fluid. The presence of adenomas, metabolic acidosis, and hypokalaemia favours this diagnosis.
villous adenomas
FAP polyps
. Familial adenomatous polyposis (FAP) is a rare inherited cancer predisposition syndrome characterised by hundreds to thousands of precancerous colorectal polyps (adenomatous polyps).
the M rule
IgM
anti-Mitochondrial antibodies, M2 subtype
Middle aged females
Primary biliary cholangitis
Inflammatory cell infiltrate in the lamina propria
Pseudopolyps
Depletion of goblet cells
Inflammation confined to the mucosa and submucosa
Ulcerative colitis
The cotton wool spots seen on fundoscopy represents***. This condition may be seen following head trauma and in conditions such as acute pancreatitis, fat embolisation, amniotic fluid embolisation, and vasculitic diseases
Purtscher retinopathy
some common factors indicating severe pancreatitis include:
age > 55 years
hypocalcaemia
hyperglycaemia
hypoxia
neutrophilia
elevated LDH and AST
Note that the actual amylase level is not of prognostic value.
High urea levels can indicate an upper GI bleed versus lower GI bleed
***** can cause oligospermia and infertility in men
Sulphasalazine
is still however associated with side-effects such as GI upset, headache, agranulocytosis, pancreatitis*, interstitial nephritis
mesalazine
pancreatitis is 7 times more common in patients taking mesalazine than sulfasalazine
a combination of sulphapyridine (a sulphonamide) and 5-ASA
many side-effects are due to the sulphapyridine moiety: rashes, oligospermia, headache, Heinz body anaemia, megaloblastic anaemia, lung fibrosis
Sulphasalazine
**** is the investigation of choice for bile acid malabsorption
SeHCAT
The SeHCAT (Selenium-75-labelled homocholic acid taurine) test is considered the gold standard for diagnosing BAM. In this test, the patient ingests a capsule containing the radiolabelled bile acid analogue SeHCAT. After 7 days, whole-body gamma camera imaging is performed to assess the retention of SeHCAT. A low retention rate indicates bile acid malabsorption.
Hepatocellular carcinoma
hepatitis B most common cause worldwide
hepatitis C most common cause in Europe
Whilst hypercalcaemia can cause pancreatitis, hypocalcaemia is an indicator of pancreatitis severity
Hypocalcaemia occurs in pancreatitis due to the saponification of fats. As lipase leaks out of the damaged pancreas, it breakdown fat into triglycerides and fatty acids. Fatty acids combine with calcium to produce soap. Therefore, reduced serum calcium can be used as a surrogate marker for the level of enzymatic damage in pancreatitis.
It is important to note that fresh PR bleeding rather than melaena does not rule out an upper GI bleed - a brisk upper GI bleed can present with fresh PR bleeding.
**** is an oesophageal perforation, it is differentiated from a Mallory-Weiss tear as it is a transmural tear rather than a mucosal tear. It can be associated with haematemesis but this is uncommon.
Boerhaave syndrome
Contraindications to percutaneous liver biopsy
deranged clotting (e.g. INR > 1.4)
low platelets (e.g. < 60 * 109/l)
anaemia
extrahepatic biliary obstruction
hydatid cyst
haemoangioma
uncooperative patient
ascites
Gastric adenocarcinoma - signet ring cells
Which tumour?
large volume diarrhoea
weight loss
dehydration
hypokalaemia, hypochlorhydia
VIPoma
90% arise from pancreas
Wilson disease Investigation
ATP7B gene
Chromosome 13
Autosommal recessive
Investigations
slit lamp examination for Kayser-Fleischer rings
reduced serum caeruloplasmin
reduced total serum copper (counter-intuitive, but 95% of plasma copper is carried by ceruloplasmin)
free (non-ceruloplasmin-bound) serum copper is increased
increased 24hr urinary copper excretion
the diagnosis is confirmed by genetic analysis of the ATP7B gene
Facial flushing is often the first symptom of carcinoid syndrome and occurs in up to 90% of patients. It is usually episodic and provoked by alcohol, stress, or certain foods.
Carcinoid syndrome Mx
Investigation
urinary 5-HIAA
plasma chromogranin A y
Management
somatostatin analogues e.g. octreotide
diarrhoea: cyproheptadine may help
**** refers to a set of immunodeficiency disorders characterised by a decrease in levels of gamma globulins including antibodies, leading to an increased risk of infections. Certain types such as common variable immunodeficiency can lead to gastrointestinal manifestations including malabsorption due to villous atrophy
Hypogammaglobulinaemia
Jejunal villous atrophy cases
Causes
coeliac disease
tropical sprue
hypogammaglobulinaemia
gastrointestinal lymphoma
Whipple’s disease
cow’s milk intolerance
Carcinoid syndrome can affect the right side of the heart. The valvular effects are tricuspid insufficiency and pulmonary stenosis
24hr oesophageal pH monitoring is gold standard investigation in ****
GORD
Gastric MALT lymphoma - eradicate H. pylori
This can lead to regression of the tumour in a significant proportion of patients.
Diarrhoea, weight, arthralgia, lymphadenopathy, ophthalmoplegia ?
Whipple’s disease
Causes of hepatosplenomegaly
chronic liver disease* with portal hypertension
infections: glandular fever, malaria, hepatitis
lymphoproliferative disorders
myeloproliferative disorders e.g. CML
amyloidosis
*the latter stages of cirrhosis are associated with a small liver
Haemochromatosis is more common than cystic fibrosis
Haemochromatosis is an autosomal recessive disorder with a carrier rate of 1 in 10 and is present in about 1 in 200-400 people. Cystic fibrosis (CF) has a carrier rate of 1 in 25 and is present in about 1 in 2,500 births. CF is often quoted as being the most common lethal inherited condition in Caucasians
Whipple is a multisysytem disorder
Features
malabsorption: diarrhoea, weight loss
large-joint arthralgia
lymphadenopathy
skin: hyperpigmentation and photosensitivity
pleurisy, pericarditis
neurological symptoms (rare): ophthalmoplegia, dementia, seizures, ataxia, myoclonus
Investigation
jejunal biopsy shows deposition of macrophages containing Periodic acid-Schiff (PAS) granules
Management
guidelines vary: oral co-trimoxazole for a year is thought to have the lowest relapse rate, sometimes preceded by a course of IV penicillin
MEN1
The hypercalcaemia and pituitary abnormality on the CT scan suggest the presence of multiple endocrine neoplasia type I (MEN I). This condition often involves tumours in the parathyroid glands (causing hypercalcaemia), pituitary gland, and gastrointestinal tract - most commonly gastrinomas in the proximal duodenum.
In a mild-moderate flare of ulcerative colitis extending past the left-sided colon, oral aminosalicylates should be added to rectal aminosalicylates, as enemas only reach so far
Colonoscopy Diffuse superficial ulceration from the rectum to the hepatic flexure
***** is a benign autosomal recessive disorder resulting in hyperbilirubinaemia (conjugated, therefore present in urine). It is due to a defect in the canillicular multispecific organic anion transporter (cMOAT) protein. This causes defective hepatic bilirubin excretion
Dubin-Johnson syndrome
Some antibiotics, such as***, have known interactions with alcohol that can cause unpleasant reactions like nausea, vomiting, flushing and headache (disulfiram-like reaction).
metronidazole and tinidazole
Pancreatic cancer Ix
Investigation
ultrasound has a sensitivity of around 60-90%
high-resolution CT scanning is the investigation of choice if the diagnosis is suspected
imaging may demonstrate the ‘double duct’ sign - the presence of simultaneous dilatation of the common bile and pancreatic ducts
Cholangiocarcinoma vs Pancreatic head cancer
Cholangiocarcinoma is incorrect because although this malignancy of the bile duct can cause obstructive jaundice and bile duct dilation, it rarely results in concurrent pancreatic duct dilation, making the ‘double duct’ sign uncommon. Cholangiocarcinoma is more often associated with risk factors such as primary sclerosing cholangitis or liver fluke infection, which are not mentioned in this patient. Additionally, cholangiocarcinoma does not typically present with a palpable mass, further distinguishing it from pancreatic head carcinoma, which compresses both ducts and often produces systemic symptoms such as weight loss and fatigue.
Hereditary haemochromatosis causes elevated ferritin, it would typically also show elevated transferrin saturation (usually >50%)
The normal anion gap ranges between
8-14 mmol/L
Metabolic ketoacidosis with normal or low glucose:
Alcoholic keto acidosis
** causes mixed metabolic acidosis and respiratory alkalosis secondary to hyperventilation. Nausea and vomiting are features of **. However, other symptoms include tinnitus, sweating and lethargy
Salicylate overdose
Lactic acidosis - lactate levels
> 5mmol/L
High Anion gap MA
Methanol
Uraemia (renal failure)
Diabetic ketoacidosis
Paracetamol use (chronic)
Iron, isoniazid
Lactic acidosis
Ethylene glycol
Salicylate overdose
**** is a recently developed monoclonal antibody fragment which binds dabigatran with an affinity that is 350 times as high as with thrombin. Consequently, idarucizumab binds free and thrombin-bound dabigatran and rapidly neutralises its activity
Idarucizumab
Drugs causing pancreatitis mnemonic
MAD Doctor Prescribed STEROIDS & SODIUM VALPROATE
M - MESALAZINE
A- AZATHIOPRINE
D- DIDANOSIN
Doctor- Diuretics (furosemide, bendroflumethiazide)
Prescribed - Pentamidine
Steroids
Sodium valproate
. HPV infection is the strongest risk factor for anal cancer. HPV infection causes 80-85% of SSCs of the anus (usually HPV16 or HPV18 subtypes).
ATP7B is the dysfunctional protein associated with Wilson’s disease.
JAK-STAT is the mutation associated with primary polycythaemia ruba vera.
Glucuronyl transferase deficiency causes Gilbert’s disease.
Alpha-antitrypsin deficiency is a protease that is associated with early onset emphysema and liver cirrhosis.
APC gene is located on chromosome
5
nearly all individuals (~100%) with untreated familial adenomatous polyposis (FAP) will develop colon cancer by their mid-40s due to the large number of polyps formed in their colon and rectum.
The features are classically a triad of:
abdominal pain: sudden onset, severe
ascites → abdominal distension
tender hepatomegaly
Budd chiari syndrome
Budd-Chiari syndrome
Budd-Chiari syndrome, or hepatic vein thrombosis, is usually seen in the context of underlying haematological disease or another procoagulant condition.
Causes
polycythaemia rubra vera
thrombophilia: activated protein C resistance, antithrombin III deficiency, protein C & S deficiencies
pregnancy
combined oral contraceptive pill: accounts for around 20% of cases
Investigations
ultrasound with Doppler flow studies is very sensitive and should be the initial radiological investigation
Transient elastography may be useful for diagnosing and monitoring the severity of liver cirrhosis
Pathology of liver cirrhosis
Excessive alcohol consumption damages hepatocytes through the formation of reactive oxygen species. Kupffer cells activation occurs and excessive profibrotic cytokines are produced leading to excessive fibrous tissue formation.
Mononuclear infiltration of liver lobules with hepatocytes necrosis and Kupffer cells hyperplasia
Viral hepatitis
Triglyceride accumulation with the proliferation of myofibroblasts
NASH
Common condition in individuals with insulin resistance, dyslipidemia and a fatty diet.
Dense lymphoid infiltrates of hepatic portal tracts with chronic inflammation and hepatocytes necrosis
This pathology is characteristic of primary biliary cirrhosis. It is liver condition seen mostly in females and affects small to medium-sized bile ducts. About 90% of patient with this condition have anti-mitochondrial antibodies.
