Biliary Tract Disease* Flashcards
What is the anatomy of the biliary tree? (10 key steps to remember)
1) Intrahepatic bile ducts, drain bile from the hepatocytes into
2) L and R hepatic duct, drain bile into
3) Common hepatic duct, drains bile into
4) Cystic duct, a two way duct which is connected to the
5) Gall bladder, a sac used to store bile and contract to release it once stimulated by leptin release in the stomach upon eating fatty foods. This releases bile back into 4, which drains into
6) Common bile duct, which joins the,
7) Pancreatic duct, responsible for draining pancreatic enzymes amylase/lipase/trypsinogen etc. Together they join in a space called
8) Ampulla of Vater, which opens via the
9) Sphincter of Oddi into
10) 2nd part of the duodenum
What is the epidemiology and risk factors for gall stones?
One of the most common admissions to general surgeons
- Multiple different presentations
Risk factors:
- ‘fat fair fertile female forty’ = BMI >30, Caucasian, 1+ children = typical demographic
SOLID:
- Sudden weight loss (rapid fat metabolism = liver secretes extra cholesterol into bile = stones)
- OCP (progesterone + oestrogen effects)
- Loss of bile salts (i.e. following ileal resection, terminal ileitis - from Crohn’s - pigment/oxalate stones)
- Increasing age
- Diabetes
Smoking
(Crohn’s gives you Stones)
What is the pathophysiology of gallstones?
Bile contents:
- Water
- Bile salts (facilitate digestion of fats/oils by forming micelle-based surfactants)
- Bile pigments (Bilirubin + biliverdin - from Hb degeneration)
- Cholesterol and phospholipids
Stone types:
- Cholesterol stones = most common, large, often solitary
- Pigment stones = small, irregular
- Mixed stones = least common (cholesterol + pigments)
How can gallstones present?
1) Asymptomatic
- Very common incidental finding on scans
2) Biliary colic
3) Cholecystitis
4) Ascending cholangitis
(+biliary sepsis)
5) Pancreatitis
6) Gall stone ileus
What is biliary colic and how does it present?
Gall stone temporarily blocking the cystic duct
Colicky RUQ pain
- Lasting 15-60+mins
- Often occurring after a heavy fatty/greasy meal or during the night
- Repeated attacks are common
- May radiate to the R shoulder
- Possible N+V
- Normal vital signs
What is cholecystitis and how does it present?
Gall stone lodged in the cystic duct (or CBD) leading to gall bladder inflammation and swelling
Constant RUQ pain
- More painful than colic
- Lasting longer than colic
- Again possibly triggered initially by fatty/greasy meal or during the night
- May radiate to R shoulder
- N+V very common
- Fever is also common
- Triad:
- Murphy’s sign +ve
- Possible mild jaundice (if CBD (partial) obstruction)
What is ascending cholangitis and how does it present?
Inflammation of the bile ducts as a result of an ascending infection from bacteria (E.coli*, Klebsiella spp., Enterococcus) in the the duodenum, often in the context of a partial/complete blockage of the biliary tree (often the CBD) by a gallstone
- May also happen if biliary strictures or tumour compression
Presents in the same way as cholecystitis/in a person with known stones
- RUQ pain + fever/rigors + jaundice = Charcot’s triad
- ” + septic shock + confusion = Reynold’s pentad
A medical emergency
What is gallstone pancreatitis?
Blockage of the pancreatic duct with a gall stone leading to back pressure within the duct and inflammation
FOR MORE CARDS SEE PANCREATITIS DECK
What is gallstone ileus and how does it present?
Not directly a gallbladder problem, nor a true ileus
Chronic gallstone in gall bladder > rubbing between duodenum and gall bladder > fistula formation > stone into small bowel lumen > passage until the next point of narrowing = ileocecal valve > obstruction
Presents like an obstruction
- SEE OBSTRUCTION DECK
What blood tests are useful in biliary disease?
WCC:
- Colic = normal
- Acute cholecystitis = +
- Acute cholangitis = +++
Bilirubin:
- (>50-may also complain of itching)
- Colic = normal
- Acute cholecystitis = +
- Acute cholangitis = +++
ALP:
- Colic = +
- Acute cholecystitis = ++
- Acute cholangitis = +++
Blood cultures in cholangitis
Lipids:
- Might be useful
Amylase/lipase:
- To rule in/out pancreatitis
What role do USS and XR play in investigating biliary disease?
USS
- Best first line - can spot 90+% of stones, measure CBD diameter (dilated in obstruction)
- Thickened GB wall >3mm in cholecystitis
A/CXR
- Not first line as not all stones are radiolucent cholesterol stones above a certain size are however - may stones are found incidentally in this manner
What special tests are used in biliary disease?
MRCP
- Magnetic retrograde cholangiopancreatography
- MR of the biliary tree
ERCP
- Endoscopic retrograde cholangiopancreatography - for diagnosis in absence of positive USS findings and for therapeutic extraction
What management is needed for biliary colic, cholecystitis and cholangitis?
Analgesia:
- Paracetamol +/- NSAIDs (incl. PR diclofenac) +/- opiates
- Often parentral as may be N+V
Antibiotics:
- For cholecystitis
- IV Abx e.g. co-amox + metronidazole
Lifestyle factor modification advice
Laparoscopic cholecystectomy +/- open conversion
- Indicated within 1wk of presentation of acute cholecystitis; can be done elective for cholelithiasis
What is aclaculus cholecystitis?
Cholecystitis picture that result from biliary stasis and/or gallbladder ischaemia
Aetiology:
- severe tissue in jury, including post-op
- DM
- Malignancy
- CCF, cardiac arrest, shock
Managed in the same way
What is primary biliary cholangiti/cirrhosis?
Progressive, autoimmune condition involving the destruction of interlobular bile ducts
- Subsequent intrahepatic cholestasis, cell damage, fibrosis and eventually cirrhosis
Aetiology
- Unknown, multifactorial; FHx strong
Rare:
- 35/100,000
- F>M at 10:1
- Median age of onset 65yrs
