In asymptomatic cases, gallbladder sludge could exist for decades. Incidental findings of gallstones occur during evaluation of the patient for abdominal pain or various gastrointestinal disturbances. This asymptomatic clinical picture does not warrant treatment. The clinical presentation can also feature a wax and wane picture in the form of biliary colic.

Biliary colic presents when gallbladder contraction causes gallstones or sludge to obstruct the cystic duct and distend the gallbladder wall. The common presentation is characterized by pain relief that coincides with gallbladder relaxation, which occurs over 30 to 90 minutes.

These episodes are typically sporadic. When obtaining the history of present illness, the patient will typically describe dull and intense pain in the right upper quadrant or the epigastrium. This pain often radiates to the right scapula, which is referred to as Collin’s sign. The onset is usually postprandial with ingestion of fatty meal. The pain remains for 1 to 5 hours and is initially intense, but gradually resolves as the gallbladder relaxes. Possible associated symptoms include nausea, emesis, and diaphoresis.

In cases where biliary colic is accompanied by cholelithiasis, there is likely fat intolerance, indigestion, dyspepsia, bloating and belching. It is not alleviated with emesis, flatus, or antacids. But it is important to note that these nonspecific symptoms can occur in people whether gallstones are present or absent. In patients with biliary colic, 1 to 3% of patients develop complications.

The second main component of the clinical presentation is the physical exam. Since biliary colic and acute cholecystitis have similar symptoms, the physical exam is beneficial to distinguish the actual condition. In uncomplicated biliary colic, the abdominal exam is benign. The patient is afebril. Rebound and guarding are absent.

In conditions such as cholecystitis, cholangitis, or pancreatitis, the clinical picture is complicated with manifestations such as fever, tachycardia, hypotension, and jaundice. Thus if any of these symptoms are exhibited, then suspicion should be high for one of these complications. Bowel sounds may be absent or hypoactive.

Acute cholecystitis is associated with Murphy’s sign. Ascending cholangitis is characterized by findings known as Charcot triad, which is featured by right upper quadrant pain, jaundice and fever. In choledocholithiasis, or CBD obstruction, scleral icterus is usually present due to accumulation of bilirubin.

In acute pancreatitis, secondary to gallstones, there is epigastric tenderness. Severe cases may present with ecchymoses and edema on flank (Grey Turner sign) and periumbilical region (Cullin sign). Acute pancreatitis is due to sludge lodged into the ampulla of Vater hence obstructing the pancreatic duct transiently. This condition is characterized by sharp, severe pain in the epigastric and abdominal areas that radiates to the back. Symptoms include nausea and emesis. These episodes can be recurrent.

• Moonshine

  Urban Moonshine Citrus Bitters. A great natural remedy for gallbladder sludge and stones. [dramyneuzil.com]

  In terms of finding products, I love digestive bitters before each meal (right now I’m addicted to some from Urban Moonshine – their citrus bitters are the bomb!) [peoplesrx.com]

• Epigastric Tenderness

  In acute pancreatitis, secondary to gallstones, there is epigastric tenderness. Severe cases may present with ecchymoses and edema on flank (Grey Turner sign) and periumbilical region (Cullin sign). [symptoma.com]

  Mild right upper quadrant or epigastric tenderness may be present; peritoneal findings are absent. Between episodes, patients feel well. Although biliary colic can follow a heavy meal, fatty food is not a specific precipitating factor. [merckmanuals.com]

• Black Vomit

  Only had one attack (complete with black vomit which they said was the sludge...lovely) but the dr fobbed me off and said I may never have another. Cue November last year...a large stone got lodged in the duct. It was horrendous. [mumsnet.com]

• Biliary Colic

  Since biliary colic and acute cholecystitis have similar symptoms, the physical exam is beneficial to distinguish the actual condition. In uncomplicated biliary colic, the abdominal exam is benign. The patient is afebril. [symptoma.com]

  Nausea and vomiting frequently accompany an episode of biliary colic. These symptoms subside when the pain episode resolves. Sweating is a common symptom of biliary colic; it is typically related to the nausea and intense pain of the episode. [livestrong.com]

  The symptom that develops most commonly is biliary colic rather than a major biliary complication. [merckmanuals.com]

  PubMed Steel PAD, 2015, Acute cholecystitis and biliary colic Emedicine Ko CW et al, 1999, Biliary sludge Annals of Internal Medicine Lee SP et al, 1992, New England Journal of Medicine Pazzi P et al, 2003, Biliary sludge: the sluggish gallbladder PubMed [ehealthstar.com]

  Overview Biliary colic and cholecystitis are in the spectrum of biliary tract disease. [emedicine.medscape.com]

• Scleral Icterus

  In choledocholithiasis, or CBD obstruction, scleral icterus is usually present due to accumulation of bilirubin. In acute pancreatitis, secondary to gallstones, there is epigastric tenderness. [symptoma.com]

• Grey Turner's Sign

  Severe cases may present with ecchymoses and edema on flank (Grey Turner sign) and periumbilical region (Cullin sign). Acute pancreatitis is due to sludge lodged into the ampulla of Vater hence obstructing the pancreatic duct transiently. [symptoma.com]

Workup includes physical examination, laboratory tests, imaging and clinical correlation. The constellation of laboratory findings taken as a whole helps determine the diagnosis and differentiate them apart.

Laboratory studies include complete blood count (CBC) with differential, liver function panel, amylase and lipase. Typically, these tests are repeated frequently to monitor the patients closely and to observe trends.

Imaging includes upright and supine abdominal radiographs which are used to rule out intestinal obstruction, visceral perforation, renal stones, or chronic calcific pancreatitis. 

Ultrasound is the recommended procedure for gallbladder or biliary conditions. The reasons for this is because of its sensitivity and specificity for detection gallstones greater than 2mm in size. Other benefits are its non invasiveness. It is also safe for pregnancy.

CT is less sensitive than ultrasonography for gallbladder sludge, but better than ultrasound for detecting gallstones in CBD. This is very useful for evaluation of abdominal pain.

MRI with MRCP (magnetic resonance cholangiopancreatography) is a noninvasive test for visualizing gallstones in biliary tract including CBD. It is performed in cases that are highly suspicious for choledocholithiasis.

Technetium-99m (99m Tc) hepatoiminodiacetic acid (HIDA) scintigraphy detects cystic duct obstruction, but is not useful for other obstructive pathologies.

Endoscopic retrograde cholangiopancreatography (ERCP) is used for imaging of the bile ducts. 

Typical findings on laboratory tests and imaging for various biliary pathologies are included below. Again, there is always variation and patients may present differently. These are findings commonly found:

Uncomplicated sludge                                                                                                    

Normal findings on laboratory tests. It is not necessary to perform labs unless there is suspicion for acute cholecystitis. Asymptomatic biliary sludge is usually an incidental finding when working up other pathologies. It is found on ultrasonography and CT. 

Acute cholecystitis

Typical lab findings include elevated WBCs (in two thirds of patients), increased LFTs if liver inflammation present. Ultrasound provides information such as gallbladder wall thickening. It also detects fluid surrounding the gallbladder and distention of the gallbladder. A key finding is the sonographic Murphy sign.

Cholangitis

Suspicion for this complication is high in presence of increasing WBCs, bilirubin, AST and ALT despite antibiotic treatment. In addition, blood culture is positive in 30-60% of patients.

Choledocholithiasis

Typical lab findings include increase in ALT and AST followed by increasing bilirubin level of which the latter is associated with an increased predictive value. With persistent obstruction of the CBD, AST and ALT decrease while alkaline phosphatase and bilirubin levels increase. If the pancreatic duct is also obstructed, lipase and amylase increase. MRI with MRCP demonstrates CBD gallstones.

• Nonvisualization of the Gallbladder

  nonfilling gallbladder, nonvisualization of the gallbladder 胆嚢内沈殿物・浮遊物 debris 超音波検査（法） ultrasonography 超音波透明帯 sonolucent layer 超音波内視鏡下穿刺（術） EUS-guided fine needle aspiration 超音波内視鏡下穿刺細胞診 EUS-guided fine needle aspiration cytology 超音波内視鏡検査 endoscopic [jsge.or.jp]

When approaching the treatment of gallbladder sludge, the goal should be to treat the risks associated with it. In asymptomatic patients, treatment is not required. In patients with biliary pain, cholecystitis, cholangitis, or pancreatitis, the treatment of choice is cholecystectomy.

In poor surgical candidates affected with cholangitis and pancreatitis, endoscopic spherectomy is useful [9]. Ursodeoxycholic acid is beneficial in the prevention of sludge formation and recurrent acute pancreatitis.

The prognosis of gallbladder sludge is not fully known. However, deducing from the fact that these patients have similar risk factors and pathogenicity as those with gallbladder stones, it is believed that they have similar prognosis as well. Furthermore, symptomatic gallbladder sludge can result in biliary complications, in which cholecystectomy may be warranted [8].  

Regarding gallstones, only 10% of asymptomatic cholelithiasis become symptomatic in the first 5 years. This number doubles by 20 years. About 19-15% of patients with gallstones have choledocholithiasis. The prognosis in these patients is correlated with the overall clinical picture and complications.

The shared etiology among gallbladder sludge, biliary sludge and gallstones is attributed to bile stasis [2] [3]. Sludge is most likely a precursor to common bile duct (CBD) stones. In fact, CBD sludge and stones have the same risk factors. Hence, when considering the risk factors of biliary sludge, consideration of predisposing factors of gallstones is warranted.

The established risk factors of cholesterol gallstones are female gender, fertile women, older age, and European or Native American background. Women with multiple pregnancies have an increased risk, likely due to pregnancy hormonal changes such as high progesterone [4] [5]. Specifically, this hormone decreases gallbladder contractility.

Certain medications pose a risk as well. These include estrogen such as oral contraceptives, which may result in increased biliary cholesterol release. Also fibrate antilipid medications and somatostatin-like medications can predispose to gallstone formation although by different mechanisms.

Obese populations are at increased risk. When evaluating etiology further, individuals with metabolic syndrome may be predisposed to developing cholesterol gallstones. The main features of this syndrome are obesity, insulin resistance, diabetes mellitus type II, hypertension and hyperlipidemia. This is thought to be secondary to hepatic cholesterol release.

Positive family history for gallstones is also correlated to the development of cholelithiasis. Other factors include preexisting diseases such as Crohn disease or those who have who have experienced burns, major trauma or received total parenteral nutrition. Further etiologies include spinal cord injuries, prolonged fasting, extreme dieting with fat restriction and rapid weight loss. Post gastric bypass individuals are at increased risk as well. 

The prevalence and other important statistics are unknown. Since this is frequently an asymptomatic condition, it is mostly found incidentally. A few studies suggest that it more common in women, but there is insufficient data to accurately deduce epidemiological information.

The pathogeneses of gallbladder sludge and gallbladder stones are similar much in the same way that they share risk factors. Sludge may resolve spontaneously or it may precipitate the formation of gallstones. The complications include biliary colic, cholecystitis, cholangitis, and acute pancreatitis [6]. 

Biliary sludge consists of bile and particulate matter. Risk factors such as certain medications and others can stimulate the sludge to progress to cholelithiasis [7]. Symptomatic sludge is treated by cholecystectomy.

Modifiable measures in prevention of symptoms involve changes in diet [10]. Some of the recommendations include eating a small breakfast as soon as patient wakes up. Furthermore is advisable to eat multiple small meals at regular intervals. Eating fewer but larger meals can exacerbate symptoms. Also important is the reduction of overall calories, fatty and cholesterol rich foods.

Gallbladder sludge, typically an incidental finding on ultrasonography or other imaging, can either spontaneously resolve, wax and wane, or progress to formation of gallstones [1]. While it can serve as a precursor of gallstones, sludge itself can also be found in cases presenting with biliary colic, acute cholecystitis, or cholangitis.

When evaluating biliary colic, it is pertinent to retrieve the clinical picture thoroughly with a consideration to risk factors in addition to a detailed physical exam looking for clues suggestive of the diagnosis. Furthermore, it is necessary to perform appropriate laboratory tests and imaging if necessary. In most symptomatic cases, treatment involves cholecystectomy.

One of the most common abdominal complaints involves gallstones. Biliary sludge is very similar. In fact, sometimes this is what makes up gallstones. Sometimes biliary sludge and gallstones do not give the patient any problems.  Most likely, there are many patients who have either of these, but do not know it because they have no symptoms. 

Biliary sludge and gallstones happen more frequent in women, especially if they have had multiple pregnancies. This is likely due to hormonal changes. This condition also tends to occur in older people and those of Native American or European ancestry. There are certain medications that can cause this as well such oral contraceptives or even cholesterol lowering drugs. 

Biliary sludge can disappear, cause symptoms, or develop into gallstone. In those who do have symptoms, usually pain after eating, especially if the food was rich in fat, occurs. These symptoms are intermittent. It is recommended that those affected by this eat small meals frequently throughout the day, with a breakfast first thing in the morning. 

An ultrasound is performed in those with symptoms to identify the cause. Also laboratory tests to check for infection and other are done. If these symptoms become severe, then a surgery is performed to remove the gallbladder. This is called a cholecystectomy. 

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