Gallbladder and Pancreas Flashcards
Causes of Gallstone (cholelithiasis) (3)
- Inc. cholesterol and/or bilirubin
- Dec. phospholipids (e.g., lecithin) or bile salts (normally inc. solubility)
- Gallbladder stasis (inc. growth of bacteria)
Cholelithiasis risk factors (4 F’s)
Female, Fat, Fertile (pregnant), Forty
Factors combine to create a high-cholesterol, low-gallbladder motility environment
Progesterone specifically inhibits gallbladder motility… in same manner that it inhibits uterine smooth muscle contraction during pregnancy
Estrogen inc. HMG CoA reductase activity (synthesis of cholesterol) and also inc. expression of LDL-R (inc. cholesterol uptake)
2 types of gallstones
- Cholesterol stones (80% of stones)
- Radiolucent with 10-20% opaque due to calcifications
- Associated with:
- Obesity
- Crohn disease
- Advanced age
- Estrogen therapy
- Multiparity
- Rapid weight loss
- Native American origin
- Bilirubin (Pigment) stones
- Black = radiopaque, Ca2+ bilirubinate, hemolysis
- Brown = radiolucent, infection
- Seen in pts with:
- Crohn disease
- Chronic extravascular hemolysis (inc. bilirubin in bile)
- Alcoholic cirrhosis
- Advanced age
-
Biliary tract infections (E. coli, Ascaris lumbricoides, Clonorchis sinensis)
- Ascaris lumbricoides = common roundworm that infects 25% of world’s population, especially in areas w poor sanitation (fecal-oral transmission) –> infects biliary tract
- Clonorchis sinensis = endemic in China, Korea, Vietnam (Chinese liver fluke)
- Total parenteral nutrition (TPN) - form of nutrition that bypasses GI
How does uncomplicated disease manifest?
Biliary colic
(neurohormonal activation… eg, by CCK after fatty meal) triggers contraction of gallbladder, forcing a stone into cystic duct
May present without pain (e.g., in diabetics)
No Murphy sign (in contrast to cholecystitis)
How to diagnose gallstones?
Treatment?
Ultrasound
Tx: cholecystectomy if symptomatic
Most common complication of gallstones
Cholecystitis
Also: acute pancreatitis, ascending cholangitis, biliary colic, gallstone ileus, gallbladder cancer
Charcot triad of cholangitis
Jaundice
Fever
RUQ
Pneumobilia
Air in biliary tree which can be caused by fistula between gallbladder and GI tract
Result: passage of gallstones into GI tract –> obstruct ileocecal valve (gallstone ileus)
Cholecystitis
Presentation
Labs
How to diagnose?
Acute or chronic inflammation of gallbladder usually from cholelithiasis (stone at neck of gallbladder)
2ndary infection often occurs (esp w E. coli, Enterococcus, Klebsiella)
Positive Murphy sign: inspiratory arrest on RUQ palpation due to pain
Labs: inc AP if bile duct becomes damaged (e.g., ascending cholangitis)
Diagnose with U/S or cholescintigraphy (HIDA, or hepatobiliary iminodiacetic acid scan)
Porcelain gallbladder
What is found on imaging?
What is found on histology?
Treatment?
Late complication of chronic cholecystitis
Calcified gallbladder; usually found incidentally on imaging
Histology:
Herniation of gallbladder mucosa into muscular wall (Rokitansky-Aschoff sinus)
Tx: prophylactic cholecystectomy due to high rates of gallbladder cancer (mostly adenocarcinoma)
Acute pancreatitis
Usually caused by gallstones present in ampulla causing reflux of pancreatic enzymes –>
- Autodigestion and inflammation of pancreas by pancreatic enzymes (pre-mature activation of trypsin leads to activation of other pancreatic enzymes)
- SPINK1 (specific trypsin inhibitor serine protease inhibitor Kazal type 1) inhibitor of autoactivation [mechanism gets messed up]
- High Ca2+ (hypercalcemic state is no good as well)
Causes of acute pancreatitis
I GET SMASHED
Idiopathic
Gallstones
Ethanol
Trauma
Steroids
Mumps
Autoimmune disease
Scorpion sting
Hypercalcemia/Hypertriglyceridemia (>1000 mg/dL)
ERCP (Endoscopic retrograde cholangiopancreatography)
Drugs (e.g., sulfa drugs, NRTIs, protease inhibitors)
Acute pancreatitis:
Diagnosis
2 of 3 criteria:
acute epigastric pain often radiating to the back
inc. serum amylase or lipase (more specific) to 3x upper limit of normal
Characteristic imaging findings (pancreas surrounded by edema)
Complications of acute pancreatitis
- Pseudocyst (formed by fibrous tissue surrounding liquefactive necrosis… lined by granulation tissue, not epithelium)
- Necrosis
- Hemorrhage
- Infection (E. coli… abdominal pain, high fever, persistently elevated amylase)
-
Organ failure (ARDS, shock, renal failure)
- ARDS: enzymes can chew on alveolar-capillary interface
- Hypocalcemia (calcium is consumed during saponification in fat necrosis)
Chronic pancreatitis
- Chronic inflammation
- Atrophy
- Calcification of pancreas (CT reveals a ‘chain of lakes’ pattern due to dilatation of pancreatic ducts)
Pancreatic adenocarcinoma
Very aggressive tumor arising from pancreatic ducts (disorganized glandular structure w cellular infiltration)
Often metastatic at presentation, with average survival ~1 yr after diagnosis (tumor in head of pancreas more common and higher prognosis b/c more likely to obstruct early –> can be detected earlier): obstructive jaundice
Associated with CA 19-9 tumor marker (also CEA, less specific)
Pancreatic adenocarcinoma: Treatment
- Whipple procedure (remove head/neck of pancreas, proximal duodenum, gallbladder)
- Chemo
- Radiation therapy
3 places gallstones can get lodged + associated symptoms
-
Cystic bile duct
- Painful gallbladder contractions
-
Common bile duct
- Pain and nausea
- Lack of bile release
- Failure to excrete bilirubin –> jaundice
-
Duodenal papilla (where common bile duct and pancreatic duct meet)
- Jaundice
- Inappropriate activation of pancreatic zymogens
- Acute pancreatitis
