The gallbladder serves as a reservoir to retain bile and release it in a bolus when fat is ingested. Fat in the stomach stimulates the release of cholecystokinin which causes the gallbladder to contract and empty when food enters the duodenum. Bile helps to emulsify and absorb fat within the small intestine while in the gallbladder, bile is concentrated by absorbing up to 70% of its water content.
| Pathogenesis of gallstones |
Bile is made up of a complex solution of bilirubin (a byproduct of aging red blood cells), cholesterol, fatty acids, and various minerals. If there is excess of one or more of the main components, the solution becomes supersaturated and cholesterol crystals form within the bile. These eventually join together to form cholesterol or "mixed" gallstones (cholesterol and bilirubin).
Loss of gallbladder motility leads to prolonged bile stasis (delayed emptying of the gallbladder) and decreased reservoir function, with the formation of bile sludge and subsequently stones. Decreased gallbladder motility is commonly observed during pregnancy (10-15 times higher incidence of cholelithiasis in women who have had children.
Black pigment stones account for almost 10% of gallstones and are most commonly seen in patients with hemolytic anemias (e.g., hereditary spherocytosis, sickle cell anemia, β-thalassemia) in which there is excess bile. not conjugated.
| Presentation |
Gallstones are very common, with an incidence of 10-15% of the adult population.
Most people with gallstones are asymptomatic and do not require prophylactic cholecystectomy.
In postmortem studies, nearly 90% of people with gallstones had no attributable symptoms during their lifetime.
> Biliary pain
Gallstones cause symptoms when the cystic duct becomes occluded during attempted expulsion of bile from the gallbladder. The resulting contraction of the smooth muscle of the gallbladder results in referred pain over the associated dermatome (T9) in the epigastrium, and irradiation in the thoracic or transverse circumference to the back. Pain originating from visceral innervation is usually poorly localized and may be accompanied by nausea or vomiting.
Local release of cytokines can cause irritation of the adjacent parietal peritoneum, resulting in pain in the right upper quadrant. The pain has a significant duration (typically 20 minutes to several hours) and the severity is sufficient to interfere with performance of activities of daily living. It is frequently very serious, often described by women as "worse than childbirth", or is misdiagnosed as a heart attack.
The popular term “biliary colic” is inappropriate since the pain is constant and relentless and is not colicky in nature; more accurately it should be called biliary pain.
The number of stones, their size, and gallbladder thickness do not correlate well with the presence, absence, or severity of biliary symptoms. In many patients with significant biliary pain, the gallbladder appears quite normal at the time of surgery.
It is important to clarify what constitutes true biliary pain to better predict relief after surgery. In 10-30% of patients with documented gallstones, cholecystectomy does not relieve symptoms . The results of cholecystectomy in patients with “biliary dyspepsia” are worse in those who suffer more classic episodes of biliary pain. The procedure should only be applied after excluding other causes, considering cases in which the possibility of achieving a benefit is less likely.
> Acute cholecystitis
When biliary pain persists for more than a few hours and is accompanied by localized discomfort in the right hypochondrium, it is called "acute cholecystitis" .
The inflammatory process results in irritation of the parietal peritoneum causing pain on palpation of the right upper quadrant during inspiration. This pain is caused by an inflamed gallbladder (Murphy’s sign).
Inflammatory markers ( white blood cell count, erythrocyte sedimentation rate, C-reactive protein) may be elevated. Liver function tests are often abnormal due to inflammation of the adjacent liver parenchyma or compression of the common bile duct by the inflamed gallbladder. Secondary infection can develop in this setting, but is rarely the primary event. However, the condition can evolve and result in various complications.
| Stones in the common bile duct |
Approximately 8-16% of patients with symptomatic gallbladder have common bile duct stones. The natural history of these stones is unknown, but there is evidence that many do not cause symptoms. However, due to uncertainty in their natural history, once discovered, most doctors advise patients to remove them, even if they are asymptomatic.
The presence of a dilated common bile duct or intrahepatic ducts with elevated liver enzymes raises the suspicion of common bile duct stones.
Classically, obstructive jaundice is accompanied by pale stools due to a lack of the brown pigment stercobilin (which requires the presence of bilirubin in the intestine) and dark urine (due to increased bilirubin in the urine).
The resulting obstructive jaundice is often associated with a history of biliary pain. This is in contrast to jaundice associated with malignant obstruction, which is usually painless and the distinction is not absolute. Common bile duct stones are best identified by magnetic resonance cholangiopancreatography or endoscopic ultrasound. These techniques have replaced endoscopic retrograde cholangiopancreatography (ERCP) in its diagnostic application.
If an infection develops in the blocked bile duct, jaundice is invariably accompanied by high fever and pain in the right upper quadrant (Charcot triad) and is called "cholangitis". The fever is typically fluctuating, with elevated temperatures of 39-40ºC, with chills and episodes of tremors (rigores).
Cholangitis results from secondary infection within the biliary tract, usually caused by duodenal enteric bacteria, most commonly Gram-negative species .
Early management with intravenous antibiotics (broad-spectrum cephalosporin or ciprofloxacin) followed by early decompression of the ducts by stone removal or stent placement. Failure to treat this condition frequently leads to septicemia, which can be fatal.
| Acute pancreatitis |
Common bile duct stones (usually small) can pass from the papilla at the bottom of the bile duct and, in some cases, cause pancreatitis. The most popular theory for the pathogenesis of gallstone pancreatitis is that a gallstone impacted in the distal part of the bile duct obstructs the pancreatic duct, increasing pancreatic pressure, with damage to the ductal and acinar cells. In this case, the indication is an early cholecystectomy to prevent further life-threatening attacks.
| Mirizzi syndrome |
First described by Argentine surgeon Pablo Mirizzi in 1948, the term is used to describe the situation in which a stone impacted in Hartmann’s pouch produces an inflammatory process that results in the adhesion of Hartmann’s pouch to the common bile duct. , with loss of space between the two (i.e., obliteration of Calot’s triangle).
The result is a partial obstruction of the common hepatic duct with altered liver function tests. The most useful is the subclassification into type I, without fistula, and type II, with erosion of the bile duct by the stone, resulting in a cholecysto-choledochal fistula.
| Treatment of gallstones |
> Non-surgical treatment
During the 1970s and 1980s there were many attempts to develop strategies for the dissolution of gallstones, using oral injection of solvents into the biliary tract and extracorporeal shock wave lithotripsy.
However, none achieved significantly reliable stone dissolution, even in highly selected study groups. To prevent recurrent stone formation, all required long-term bile salt treatments (with a high incidence of abdominal cramps and diarrhea).
Other alternative treatments such as “gallbladder discharge” (basically consisting of administering purgative agents such as Epsom salts, olive oil and lemon juice) have been popularized on the Internet, but there is no evidence of their effectiveness. These treatments result in the production of small, granule-shaped stools that can be mistaken for stones by enthusiasts of the procedure.
| Cholecystectomy |
Patients with biliary pain should be offered a cholecystectomy as definitive treatment for their disease. Currently in the UK, 99% of procedures are performed laparoscopically and 70% as day surgery.
> Acute cholecystitis
Patients with acute cholecystitis generally require hospitalization for analgesia and intravenous rehydration.
Non-steroidal anti-inflammatory agents reduce inflammation and accelerate recovery, and broad-spectrum antibiotics, mainly second-generation cephalosporins, to prevent secondary bacterial infections. Patients must undergo emergency laparoscopic surgery. ideally within the first 72 hours of being admitted.
> Gallstones
There are two main approaches to removing common bile duct stones:
• Endoscopic retrograde cholangiopancreatography and surgical exploration of the bile ducts : ERCP is the most common approach for the management of common bile duct stones. It involves the oral insertion of a lateral viewing endoscope (duodenoscope) that is introduced until it reaches the duodenum. The papilla is cannulated with a fine cannula to enter the bile duct.
The papilla can be cut with a sphincterotome, which through diathermy divides the sphincter of Oddi, allowing the stones to be removed. Larger stones can be crushed with a mechanical lithotripter. ERCP is performed with the patient under sedation and carries the risk of acute pancreatitis due to manipulation of the papilla (approximately 5%), bleeding or perforation (approximately 1%), and death (0.1%).
• Surgical exploration of the bile ducts : Exploration of the bile ducts was originally done by laparotomy, but is increasingly done laparoscopically. The transcystic approach is limited to stones small enough to be removed through the cystic duct (typically, stones <5 mm). Larger stones can be managed directly by the transductal approach, through an incision in the common bile duct. Impacted stones can be removed by breaking them up under direct vision with contact lithotripsy.
| Postoperative problems (chronic) |
The resolution of post-cholecystectomy pain depends on case selection.
Post-cholecystectomy pain is invariably the result of pre-cholecystectomy symptoms or other diagnoses, and there is no evidence that the laparoscopic cholecystectomy procedure itself results in the development of abdominal pain.
Patients can return to a normal diet without restrictions on fat or other specific food intake. After laparoscopic cholecystectomy, almost 5% of patients develop a looser bowel habit or urgency in defecation, although these are often patients who already had some degree of symptoms (eg, irritable bowel syndrome).
It is thought to be caused by a more constant flow of bile into a relatively empty intestine. In half of those affected it resolves in 3-6 months, when a degree of adaptation occurs. Patients who continue to have diarrhea problems may improve with loperamide, which controls urgency, and/or a bile-binding agent such as cholestyramine.
