| What are types of gall stones? | Based on composition (cholesterol, pigment and rare stones)
majority (75%) are cholesterol stones (cholesterol crystals + calcium bilirubinate, subclassified into pure cholesterol and mixed stones w/50% cholesterol at least)
Pigment galls stones (20% black (mostly of calcium bilirubinate) and 4.5% brown)
Rare (0.5%) include calcium carbonate and fatty acid calcium stones. |
| How are gall stones classified by their location? | Intrahepatic, gall bladder and bile duct stones (choledocholithiasis).
Intrahepatic are predominantly brown pigment stones with small group of black pigment, bile duct stones are mixed cholesterol stones mostly. |
| How is the epidemiology of gall stones? | Prevalence in women 5-20% age 20-55, 25-30% after 50
in men half this prevalence.
90% stones are from gall bladder, and 10% from common bile duct |
| What are risk factors for getting gall stones? | Age and gender, diet, pregnancy, rapid weight loss, total parental nutrition, biliary sludge, drugs (estrogen, lipid lowering, octreotid, ceftriaxone), lipid abnormalities, systemic disease (obesity, DM, ileum disease, spinal cord injuries) |
| What are protective factors against gall stones? | Statins, ascorbic acids, coffee. |
| How is pathophysiology of gall stones? | Genetic factors (LITH gene), hepatic hypersecretion of cholesterol, gallbladder hypomotility, rapid phase transitions of cholesterol, intestinal factors all play a role in cholesterol nucleation and crystallization and forming cholesterol gall stones.
As for pigmented stones, abnormalities in bilirubin metabolism and bilirubin precipitation, for black pigmented stones uninfected gallbladders with chronic hemolytic anemia (b-thalassemia, SCA), ineffective erythropoiesis (pernicious anemia), ileal diseases (Crohn's) w/ excess bile salts into large intestine, ileal resections, and liver cirrhosis play a role
For Brown pigmented stones, not only gallbladder but also bile duct formation, especially intrahepatic, due to stasis of bile associated with biliary infection (E.coli especially) |
| What are asymptomatic stones? | Rate is 2% per year to develop asymptomatic stone for 5 years and decreases with time.
First manifesting symptom of a previously asymptomatic stone is biliary pain (90%), but low frequency of complication and unnecessary prophylactic cholecystectomy (especially for insulin-resistant DM) |
| What are symptomatic gall stones? | Cardinal symptom is biliary pain (colic) which is RUQ pain radiating to the back w/ or w/out nausea.
Pt w/ previous episode of pain have rate of recurrency 38% per year (for uncomplicated pt)
Biliary complications are more likely to develop w/symptomatic gallstones (more than asymptomatic) w/ risk estimated 1-2% per year and is constant over time.
Cholecystectomy should be done after biliary symptoms occur. |
| What are the complications of gall stones occurring in each part of the bile duct? | . |
| What are the uses of US in gall stones? | Tests for cholelithiasis (mobile stones in gall bladder, echogenic, best test for stones in gall bladder)
Choledocholithiasis (stones in bile duct, we could se dilated BD >6mm w/ or w/out stones)
Acute cholcystitis (Murphy's sign [palpate gall bladder and pain is felt], when stones are seen confirm it |
| What are the uses of EUS in gall stones? | Choledocholithiasis (confirms stones in BD, similar as ERCP but more sensitive, can be used along with ERCP to confirm if low or intermediate risk) |
| What is the use of oral cholecystography? | Cholilithiasis sees opacified stones in gall bladder |
| What is the use of cholescintigraphy? | Assesses acute cholecystitis (normally we see radioactivity in gall bladder, and abnormal is non visualization of the gall bladder w/preserved hepatic excretion of radioactive substance into the BD |
| What is the use of ERCP? | Choledocholithiasis (std dx test for them, and used to extract stones, life saving in severe cholangitis, recommended for pt with high risk of choledocholethiasis)
Cholelithiasis (US is better for confirmation than ERCP but it can show them) |
| What is the use of MRCP? | Choledocholithiasis (provides detailed image of duct, useful for examination of duct (especially proximal part), recommended for pt w/low to moderate clinical probability of choledoc) |
| What is the use of CT in gall stones? | Complications of gall stones, excellent detector of abscesses, perforations, BD, pancreatitis (Especially spiral CT)
Not used to detect uncomplicated gall stones although |
