10-20% of adults in Western cultures have gallstones, this may or may not be the cause of the clinical presentation!
cholesterol stones are not confined to patients who are Fat, Female, Fertile and Forty, but prevalence generally starts to rise after puberty and men also get these stones, albeit at a rate half that of women.
rapid weight loss or major illness or trauma are also important factors!
fasting USS is the preferred Ix as CT may fail to detect gallstones because many stones are isodense with bile however, CT will generally detect ~75% of gallstones
patients with symptomatic gallbladder gallstones should generally be referred to the surgical team
patients with choledocholithiasis are generally referred to the gastroenterology team
introduction
gallstones are stones which form insidiously within the gallbladder, and most remain asymptomatic but if they obstruct the cystic duct may cause biliary colic or if this obstruction lasts more than a few hours, it may lead to cholecystitis
the stones may pass into the common bile duct (CBD) or form within the CBD and this is termed choledocholithiasis, these tend to become impacted distally at the ampulla of Vater and may lead to biliary colic and the life threatening conditions, ascending cholangitis and pancreatitis.
the finding of gallstones within the gall bladder does NOT of itself mean that they are the cause of the patient's symptoms, as many are asymptomatic and may lead to misdiagnosis.
once they become symptomatic, it is usually an indication for cholecystectomy, preferably, electively.
elderly patients are more likely to progress from asymptomatic gallstones to serious complications of gallstones and cholangitis.
chronic gallbladder inflammation may lead to cancer of the gallbladder
hence patients with porcelain gallbladder (calcification of gallbladder wall seen on X-ray) are usually referred for cholecystectomy
patients may develop cholecystitis without the presence of gallstones - “acalculous cholecystitis”
these patients are generally very unwell hospitalised patients such as post-op or ICU patients, but it may occur in outpatients
high morbidity and mortality rates
types of gallstones
cholesterol stones
in Western cultures, 80% are cholesterol stones - that is cholesterol is their main component
the main factors that determine whether cholesterol gallstones will form are:
the amount of cholesterol secreted by liver cells, relative to lecithin and bile salts, and
the degree of concentration and extent of stasis of bile in the gallbladder
risk factors for formation of cholesterol stones:
traditional clinical mnemonic: “Fat, Female, Fertile, and Forty” indicates the main risk factors, HOWEVER, it should not be forgotten that men still get gallstones, it is just that women are about twice as likely to have them, and men tend to get them at an older age.
metabolic syndrome of truncal obesity, insulin resistance, type II diabetes mellitus, hypertension, and hyperlipidemia is associated with increased hepatic cholesterol secretion and is a major risk factor for the development of cholesterol gallstones.
pregnancy
more common in women who have experienced multiple pregnancies
a major contributing factor is thought to be the high progesterone levels of pregnancy.
progesterone reduces gallbladder contractility, leading to prolonged retention and greater concentration of bile in the gallbladder
a common time for clinical presentation of biliary disease is in the puerperium!
gallbladder stasis
progesterone (see above)
high spinal cord injuries
prolonged fasting with total parenteral nutrition,
rapid weight loss associated with severe caloric and fat restriction (eg. diet, gastric bypass surgery).
burns, ICU care, and major trauma.
drugs
oestrogens administered for contraception or for treatment of prostate cancer increase the risk of cholesterol gallstones by increasing biliary cholesterol secretion
clofibrate and other fibrate hypolipidemic drugs increase hepatic elimination of cholesterol via biliary secretion
genetics contribute 25% of risk
at least a dozen genes may contribute to the risk
prevalence of gallstones is highest in:
fair-skinned people of Northern European descent
Hispanic populations, Native Americans, and Pima Indians
an Irish study in 2013 showed family history is one of the strongest risk factors for gallstone formation, even stronger than the traditional “5 F's” mnemonic (female, fertile, fat, fair, forty) 1)
a large Chinese study showed risk of gallstones requiring cholecystectomy 2)
FH of gallstones has a OR of 2.8
FH of cholecystectomy has a OR of 3.3
having more than one relative with a history of gallstones further increased the risk (OR=2.3)
excess risk associated with a family history was observed across all types of first-degree relatives (parents, siblings, and offspring), with the highest risk seen for subjects having an affected sibling (OR=4.0, 95% CI=2.5-6.4), especially a brother (OR=5.0, 95% CI=2.3-10.8)
reduced bile salts:
Crohn's disease, ileal resection, or other diseases of the ileum decrease bile salt reabsorption and increase the risk of gallstone formation.
possibly microplastics
bile in the gallbladder appears to accumulate and excrete microplastics and microplastics may increase cholangiocyte cell stress and senescence and those with gallstones appear to have 4x as much microplastics - most particles measured 20-50 μm 3)
prevention
short-term prophylaxis with ursodeoxycholic acid should be considered for patients at acute risk of developing cholesterol stones such as those likely to undergo rapid weight loss from aggressive dieting or bariatric surgery
specific foods in the diet otherwise does not appear to have a significant impact
calcium, bilirubin, and pigment gallstones
black pigment stones
represent 10-20% of gallstones in Western cultures
they are mainly due to increased heme turnover such as chronic haemolysis or cirrhosis
African Americans with sickle cell disease
brown pigment gallstones
are unusual in Western cultures but are fairly common in some parts of Southeast Asia, possibly related to liver fluke infestation
these stones tend to form in the CBD as a result of bacterial action on lecithin forming fatty acids
mixed stones
in chronic inflammation, over time, cholesterol stones may accumulate a substantial proportion of calcium bilirubinate and other calcium salts, producing mixed gallstones.
large stones may develop a surface rim of calcium resembling an eggshell that may be visible on plain x-ray films