Cholecystitis (GI) Flashcards
Define acute cholecystitis.
Acute gallbladder inflammation usually due to cystic duct obstruction by a gallstone
What are 90% of cases of acute cholecystitis caused by?
Gallstones
Complete cystic duct obstruction usually due to an impacted gallstone in the GB neck or cystic duct –> bile trapped in GB –> inflammation within GB wall
How do impacted gallstones cause acute cholecystitis?
Complete cystic duct obstruction usually due to an impacted gallstone in the GB neck or cystic duct –> bile trapped in GB –> irritation of surrounding nerves –> increases GB pressure
Trauma caused by gallstones stimulate PG synthesis (PGI2, PGE2), mucus enzyme production from GB mucosa –> inflammatory response
What happens if gallstone remains impacted in acute cholecystitis?
Pressure continues to build and can impact blood vessels –> compromised blood supply to GB –> ischaemia/necrosis of tissue
What can cause acalculous acute cholecystitis (without gallstones)? (7)
- bile inspissation (due to dehydration)
- bile stasis (trauma/systemic illness)
- starvation
- TPN
- narcotic analgesics
- immobility
- EBV
What are the clinical features of acute cholecystitis? (4)
- RUQ pain + tenderness
- pain may radiate to right shoulder (parietal peritoneum involvement)
- fever and signs of systemic upset
- nausea and vomiting (more common if stone in CBD)
- (jaundice - less common, inflammation and oedema around biliary tract, pressure on tract)
Why is jaundice rarely seen in acute cholecystitis?
Blockage of cystic duct or GB does not cause jaundice
What might you see on examination of acute cholecystitis? (3)
- Murphy’s sign (sudden pause during inspiration upon deep palpation of RUQ due to pain as diaphragm hits enlarged GB)
- palpable mass - distended, tender GB
- Boas sign - hyperaesthesia below right scapula
What are some risk factors for acute cholecystitis? (4)
- gallstones
- total parenteral nutrition –> fasting = GB hypomotility and stasis, biliary sludge, gallstones (decreased emptying)
- diabetes
- severe illness
What are the first-line investigations for acute cholecystitis? (8)
- abdominal USS
- CT/MRI abdomen
- FBC
- CRP
- LFTs
- serum lipase/amylase
- MRCP
- EUS
What is the first-line investigation of choice for suspected acute cholecystitis?
Abdominal ultrasound (showing thick gallbladder wall)
What would you see on abdominal ultrasound in acute cholecystitis? (5)
- pericholecystic fluid
- distended gallbladder
- thickened gallbladder wall (>3mm)
- gallstones
- positive sonographic Murphy’s sign (may be absent in gangrenous cholecystitis)
What do we do if abdominal ultrasound is unclear in suspected acute cholecystitis?
Technetium labelled HIDA scan
What investigation do we do if sepsis is suspected in acute cholecystitis?
CT/MRI abdomen - diagnosing gangrenous cholecystitis or perforation
What is the gold-standard (but not first-line) investigation for acute cholecystitis?
- MRCP
- can also show defects in biliary tree
- use if US does not show stones but bile duct is dilated OR if LFTs are abnormal
- use EUS if MRCP contraindicated
