Corrections 3 Flashcards
What type of virus is CMV?
One of the herpes viruses
Who does CMV typically only cause disease in?
HIV or those immunosuppressed following organ transplantation
Mx of CMV infection?
IV ganciclovir
Features of congenital CMV?
- growth retardation
- pinpoint petechial ‘blueberry muffin’ skin lesions
- microcephaly
- sensorineural deafness
- encephalitiis (seizures)
- hepatosplenomegaly
What levels should be checked 4 months following immunisation against hep B to ensure an adequate response to immunisation?
Anti-HBs
Transmission of hep A, B, C, D & E?
Hep A: faeco-oral
Hep B: blood-borne
Hep C: blood-borne
Hep D: blood-borne
Hep E: faeco-oral
Hepatitis D only occurs in people who are also infected with what?
Hep B
Hep D co-infection vs superinfection?
Co-infection: Hepatitis B and Hepatitis D infection at the same time.
Superinfection: A hepatitis B surface antigen positive patient subsequently develops a hepatitis D infection.
Purpose of giving irradiated blood?
Reduces risk of graft versus host disease by destroying T cells
What class of abx is typically used in the mx of a variceal haemorrhage?
Quinolones e.g. ciprofloxacin
Give 3 indicators of a ‘life-threatening’ C. diff infection (requiring IV metronidazole + oral vancomycin)
1) hypotension
2) partial or complete ileus
3) toxic megacolon or CT evidence of severe disease
Purpose of prescribing albumin when treating large volume ascites with paracentesis?
Reduce post-paracentesis circulatory dysfunction
Formula for units in alcohol?
Units = ml x % / 1000
What antibody may be positive in PSC?
p-ANCA
What is the most sensitive and specific lab finding for diagnosis of liver cirrhosis in those with chronic liver disease?
Thrombocytopenia
For patients with NAFLD, what investigation is recommended to screen for patients who need further testing?
enhanced liver fibrosis score
A lemon tinge to the skin is associated with what condition?
Pernicious anaemia (due to mild jaundice combined with pallor)
Pathophysiology behind pernicious anaemia?
1) antibodies to intrinsic factor +/- gastric parietal cells
2) intrinsic factor antibodies → bind to intrinsic factor blocking the vitamin B12 binding site
3) gastric parietal cell antibodies → reduced intrinsic factor production → reduced vitamin B12 absorption
4) vitamin B12 is important in both the production of blood cells and the myelination of nerves → megaloblastic anaemia and neuropathy
What is the most common cause of B12 deficiency?
Pernicious anaemia
What conditions is pernicious anaemia associated with?
Other autoimmune disorders e.g. thyroid disease, T1DM, Addison’s, vitiligo, RA
Features of pernicious anaemia?
1) anaemia features
2) neuro:
- peripheral neuropathy (‘pins and needles’)
- subacute combined degeneration of the spinal cord
- neuropsychiatric features
3) mild jaundice: combined with pallor results in a ‘lemon tinge’
4) atrophic glossitis → sore tongue
Symptoms of subacute combined degeneration of the cord?
- progressive weakness
- ataxia
- paresthesias
- may progress to spasticity and paraplegia
What is there an increased risk of in pernicious anaemia?
Gastric cancer
What cancer can PSC predispose to?
Cholangiocarcinoma
Screening for haemochromatosis in:
a) general population
b) family members
a) transferrin saturation (& ferritin)
2) HFE testing
Features of carcinoid tumours?
- flushing
- diarrhoea
- bronchospasm
-hypotension
- right heart valvular stenosis
- ACTH and GHRH may also be secreted (e.g. resulting in Cushing’s)
- pellagra
How can pellagra sometimes rarely develop in carcinoid tumours?
As dietary tryptophan is diverted to serotonin by the tumour
How can Cushing’s develop as a result of a carcinoid tumour?
Carcinoid tumours can secrete pituitary hormones, such as ACTH
1st line investigation in a carcinoid tumour?
Urinary 5-HIAA
Mx of a carcinoid tumour?
somatostatin analogues e.g. octreotide
diarrhoea: cyproheptadine may help
What is the first marker to appear in Hep B infection?
HBsAg (surface antigen)
What is HBsAg positive in?
Acute & chronic infection
(if positive >6 months then this implies chronic disease i.e. infective)
What does positive anti-HBsAg indicate?
Immunity due to vaccination
What does positive Anti-HBcAg IgM indicate?
Acute infection
What does positive Anti-HBcAg IgG?
Either:
a) acute infection (*IgG levels will not rise until 1/2 months into an infection)
b) chronic infection
3) immunity due to previous infection
Hep B serology results in previous immunisation?
Positive anti-HBsAg
All others negative
Hep B serology results in previous hep B (>6 months ago), not a carrier?
anti-HBc positive
HBsAg negative
Hep B serology results in previous hep B, now a carrier?
anti-HBc positive
HBsAg positive
Does UC flare up to the splenic flexure count as a distal flare?
Yes - 1st line is rectal aminosalicylates
What is the investigation of choice for diagnosis of small bowel overgrowth syndrome?
Hydrogen breath testing
Mx of Barrett’s oesophagus?
1) high dose PPI
2) endoscopic surveillance with biopsies (every 3-5 years)
3) if dysplasia of any grade is identified endoscopic intervention is offered.
1st line intervation in Barrett’s with dysplasia?
1st line –> radiofrequency ablation
2nd line –> endoscopic mucosal resection
What does C. difficile antigen positivity only show?
Exposure to the bacteria, rather than current infection (i.e. C. diff colonisation)
What should be avoided prior to a urea breath test for H/ pylori?
Antibiotics –> stop 4 weeks before
Antisecretory drugs (e.g. PPIs, H2 receptor antagonists) –> stop 2 weeks before
Histology of coeliac disease?
- villous atrophy
- raised intra-epithelial lymphocytes
- crypt hyperplasia
What are the 4 grades of hepatic encephalopathy?
Grade I: irritability
Grade II: confusion, inappropriate behaviour
Grade III: incoherent, restless
Grade IV: coma
Mx of patients who do not meet referral criteria (‘undiagnosed dyspepsia’)?
1) Review medications for possible causes of dyspepsia
2) Lifestyle advice
3) Trial of full-dose PPI for one month OR a ‘test and treat’ approach for H. pylori
(if symptoms persist after either of the above approaches then the alternative approach should be tried)
What 2 investigations are recommended for the initial diagnosis of H. pylori?
1) carbon-13 urea breath test
or
2) stool antigen
Are granulomas seen in UC or Crohn’s?
Crohn’s
Are pseudopolyps seen in UC or Crohn’s?
UC
What is key in determining the severity of C. difficile infection?
WCC
What investigations are required in patients with GORD being considered for fundoplication surgery?
1) Endoscopy
2) Barium swallow
3) Oesophageal pH
4) Manometry studies
What mx can be done in treatment resistant GORD?
Nissen fundoplication
Role of oesophageal manometry?
This measures the pressures within the lower oesophageal sphincter and helps to confirm the diagnosis of GORD.
What weight loss is diagnostic of malnutrition?
Unintentional weight loss greater than 10% within the last 3-6 months
What are the 3 possible criteria for a diagnosis of malnutrition?
1) BMI <18.5
2) BMI <20 and unintentional weight loss greater than 5% within the last 3-6 months
3) Unintentional weight loss greater than 10% within the last 3-6 months
What does a TIPS connect?
The hepatic vein to the portal vein
Is transferrin saturation or ferritin better for haemochromatosis screening?
Transferrin saturation
What drugs can cause acute pancreatitis?
- mesalazine
- steroids
- sodium valproate
- furosemide
- bendroflumethiazide
- azathioprine
What 2 respiratory conditions may acute pancreatitis cause?
1) ARDS
2) Pleural effusion (exudative)
How can LFTs determine the cause of acute pancreatitis?
Raised bilirubin –> gallstones
Isolated raised gamma-GT –> alcohol
Role of testing faecal elastase in chronic pancreatitis?
Can be used to assess exocrine function: reduced levels are indicative of exocrine pancreatic insufficiency
How can chronic pancreatitis increase risk of osteoporosis?
Malabsorption of vit D & calcium as well as chronic inflammation.
What are the 2 most common cause of ascending cholangitis?
1) gallstones
2) post-ERCP
What does ERCP involve?
The passage of an endoscope into the 2nd part of the duodenum and cannulation of the ampulla.
Role of ERCP in ascending cholangitis?
Can determine the underlying cause of cholangitis and can also be therapeutic, by way of stone extraction and/or stent placement.
What is the gold standard investigation and intervention for acute cholangitis?
ERCP
Why is ERCP not always used in cholangitis?
Is invasive and therefore carries much more risk than other imaging modalities.
As a result, it is frequently preceded by MRCP where available.
What imaging is typically used if US is negative in ascending cholangitis?
Contrast enhanced CT-abdomen
What is a sphincterotomy?
Incising the sphincter of Oddi, where the biliary system joins the duodenum.
This aids drainage and passage of any CBD stones.
How can temp affect acute pancreatitis?
Hypothermia can cause acute pancreatitis
What drugs are a risk factor for peptic ulcer disease?
(4)
1) NSAIDs
2) Steroids
3) Bisphosphonates
4) SSRIs
What type of bacteria is H. pylori?
Gram -ve aerobic
LFTs in acute cholecystitis?
Typically normal
Where can biliary colic pain radiate to?
Interscapular region
Is mesalazine or sulfasalazine a bigger risk factor for pancreatitis?
Mesalazine
Describe pain in acute diverticulitis
Colicky abdo pain in LIF
What Glasgow-Blatchford score indicates a high risk for an upper GI bleed?
Above 0
Consider early discharge in patients with a score of 0
What are 2 main complications of an acute haemolytic transfusion reaction?
1) DIC
2) Renal failure
How is a diagnosis of chronic mesenteric ischaemia made?
CT angiography
Best way to manage variceal haemorrhage whilst waiting for endoscopy?
Insert a Sengstaken-Blakemore tube
What is the area most likely to be affected by ischaemic colitis?
Splenic flexure
What are 2 common bacterial contaminants of platelet transfusions?
1) Staph. epidermis
2) Bacillus cereus
1st line investigation in acute mesenteric ischaemia?
Lactate (VBG)
ACute vs chronic mesenteric ischaemia
Both affecting small bowel
Acute –> typically caused by AF
Chronic –> ‘intestinal angina’, typically preceded by eating
If endoscopy is negative, what is next step in GORD?
24hr oesophegeal pH monitoring
Gold standard test for diagnosis of GORD?
24hr oesophageal monitoring
Mechanism of PPIs?
Irreversibly block the H+/K+ ATPase of the gastric parietal cell –> reduce gastric acid secretion
What is involved in fundoplication?
Tying the fundus of the stomach around the lower oesophagus to narrow the lower oesophageal sphincter.
What is the most commonly affected section of bowel in diverticulosis?
Sigmoid colon
What type of laxatives can be offered in diverticulosis if patients have constipation?
Bulk-forming e.g. ispaghula husk
What type of laxatives should be AVOIDED in diverticulosis?
Stimulants
Is a colonoscopy indicated in diverticulitis?
No - should be avoided initially due to the increased risk of perforation in diverticulitis
What investigation is recommended for assessing liver fibrosis in chronic hepatitis C?
Transient elastography
What is the investigation of choice for Meckel’s diverticulum in stable children?
Technetium scan
What is the most common cause of pseudomembranous colitis?
C. diff infection (typically following abx)
Patients with diverticulitis flares can be managed with oral antibiotics at home. If they do not improve within 72 hours, what is next step?
Admit for IV ceftriaxone + metronidazole
Give 3 drugs that can cause cirrhosis
1) methotrexate
2) amiodarone
3) sodium valproate
Caeruloplasmin levels in liver disease?
Low
Caeruloplasmin levels in Wilson’s?
Low (due to liver disease)
Urinary copper will be high
What is a tumour marker for HCC?
AFP
1st line investigation for assessing fibrosis in NAFLD?
Enhanced liver fibrosis (ELF) test
What investigation can help determine liver fibrosis?
Transient elastography (fibroscan)
Who is a transient elastography used in?
Patients AT RISK of cirrhosis:
1) Alcohol-related liver disease
2) Heavy alcohol drinkers
3) NAFLD & advanced liver fibrosis (indicated by ELF test)
4) Hep C
5) Chronic hep B
What score gives an estimated 3-month mortality as a percentage for patients with compensated cirrhosis?
MELD (Model for End-Stage Liver Disease) score
How often should MELD score be used?
Every 6 months in patients with compensated cirrhosis.
What score measures the severity of cirrhosis & prognosis?
Child-Pugh score
How are complications monitored for in cirrhosis?
1) MELD score every 6m
2) US & AFP every 6m
3) Endoscopy every 3 years for oesophageal varices
What are the 4 key features of decompensated liver failure?
AHOY
A: Ascites
H: Hepatic encephalopathy
O: Oesophageal varices
Y: Yellow (jaundice)
How does cirrhosis lead to splenomegaly?
Portal HTN
If beta blockers are contraindicated, what is the next option for prophylaxis of bleeding in stable oesophageal varices?
Variceal band ligation
What are the 2 main indications for TIPS?
1) refractory ascites
2) bleeding oesophageal varices
How does cirrhosis lead to fluid and sodium retention?
1) Loss of fluid to peritoneal cavity (ascites)
2) The drop in circulating volume caused by fluid loss into the peritoneal cavity causes reduced blood pressure in the kidneys.
3) Kidneys release renin in response
4) This causes increased aldosterone secretion via the renin-angiotensin-aldosterone system.
5) Increased aldosterone causes the reabsorption of fluid and sodium in the kidneys
When are prophylactic abx indicated in ascites?
<15 g/L protein in ascitic fluid
What are the 2 most common organisms causing SBP?
1) E. coli
2) Klebsiella
Mx of SBP?
1) Taking a sample of ascitic fluid for culture before giving antibiotics
2) IV broad-spectrum antibiotics according to local policies (e.g., piperacillin with tazobactam)
What is most important toxin that can build up in cirrhosis?
Ammonia
What is Abx of choice in hepatic encephalopathy?
Rifaximin
Define binge drinking
6 or more units for women or 8 or more units for men in 1 sitting
What AUDIT score indicates harmful drinking?
≥8
What is metabolic syndrome?
Obesity + diabetes + HTN
What is often first indication in LFTs that a patient has NAFLD?
Raised ALT
What is the normal AST:ALT ratio?
<1
ALT vs AST in NAFLD?
ALT is typically greater than AST
(compared to alcohol fatty liver)
What gene mutation is involved in haemochromatosis?
C282Y mutation in human haemochromatosis protein (HFE) gene on chromosome 6
What can be used to establish the iron concentration in the liver?
Liver biopsy with Pearl’s stain, or MRI
Complications of haemochromatosis?
) 2ary diabetes (iron affects the functioning of the pancreas)
2) Liver cirrhosis
3) Endocrine and sexual problems (hypogonadism, erectile dysfunction, amenorrhea and reduced fertility)
4) Cardiomyopathy (iron deposits in the heart)
5) HCC
6) Hypothyroidism (iron deposits in the thyroid)
7) Chondrocalcinosis (calcium pyrophosphate deposits in joints) causes arthritis (pseudogout)
How is copper excreted?
In the bile
What is A1AT?
Protease inhibitor
What is a critical protease enzyme that is inhibited by alpha-1 antitrypsin?
Neutrophil elastase.
What can a liver biopsy show in alpha-1 antitrypsin deficiency?
Liver biopsy shows periodic acid-Schiff positive staining globules in hepatocytes, resistant to diastase treatment.
These represent a buildup of the mutant proteins.
What is the 1st line treatment for patients with advanced (including metastatic) HCC?
Sorafenib
