- Around 10-15% of the adult population (in the developed world) will develop gallstones. The majority are asymptomatic- only 1-4% develop symptoms. However, symptomatic gallstones often present recurrently and can be in danger of causing serious complications (see below). As a result, all patients with symptomatic gallstones should be offered cholecystectomy.
- Occur when there is dysequilibrium of the chemical components of bile which results in the formation of a stone.
- Most commonly (80%) are cholesterol stones; the remainder are either calcium, bilirubin or pigment stones (the latter two are usually secondary to haemolysis (there are also mixed stones).
- Gallstones are known to be more common in women, obese individuals, older individuals, pregnancy, diabetics, following weight loss etc
- The OCP increases the risk of gallstones
- More common in iron deficient anaemia
- Also often present in carcinoma of the gallbladder
Potential Complications of Gallstones
- Biliary colic
- Acute cholecystitis
- Ascending cholangitis
- Biliary empyema
- Gallstone ileus
- Perforated gallbladder/biliary tree
- As mentioned, some patients may have gallstones diagnosed as a coincidental finding and the patient may be completely asymptomatic
These do not require treatment but a watchful waiting approach should be used in case things are worse.
- In symptomatic patients, symptoms can often be precipitated by a fatty meal. A ‘gallbladder attack’ involves
- Stady pain in the right upper abdomen that has peaks in severity (colic) and can last from 30 mins to usually <8 hours.
- Biliary colic does not present with any RUQ examination, fever or jaundice
Investigations and Management
- Bloods: LFTs (Alk Phos and bilirubin are classically raised in gallstone cholecystitis; clotting screen (liver is the site of production for clotting factors 2, 7, 9 and 12)
- Ultrasound is the first line investigation of gallstones
- The bile duct (common) should be <7mm wide, there should be no thickening of the gallbladder wall.
- MRCP and ERCP are indicated only really when there is associated jaundice, deranged LFTs, a significantly dilated bile duct on USS; recent pancreatitis/cholangitis etc
- MRCP is the most effective way of imaging these patients in whom you are not fully certain require cholecystectomy management e.g. deranged LFTs but normal USS or vice versa.
- ERCP is the most common method of both identifying cholelithiasis but, more importantly now, it is used to treat gallstones in the acute setting:
- NB ERCP is an invasive procedure that carries 1% risk of perforation (and usually subsequent mortality). It also has risks of bleeding, pancreatitis etc
- As such, a clotting screen must be done prior to investigation and, ideally, anticoagulants should be stopped up to a week before the procedure.
- Post-ERCP, amylase levels should also be measured.
- Where possible, stone extraction and sphincterotomy are performed. Otherwise, stenting is an alternative method.
- If ERCP is unsuccessful, the patient will require surgery for the removal of the gallbladder if they are fit to do so
- Cholecystectomy (laparoscopic) is the mainstay of treatment for the majority of chronic, known gallstones who are at low risk and who are symptomatic.