Biliary sludge

Biliary sludge has been associated with pregnancy, rapid weight loss, total parenteral nutrition, drugs such as ceftriaxone and octreotide, solid organ transplantation, and gastric surgery.[1][2] In many of these conditions, it is thought that the impairment in the contractility of the gallbladder leads to the formation of the sludge.[2]

The pathophysiology of biliary sludge formation is likely related to gallbladder dysmotility.[2] It is presumed that because the gallbladder is unable to effectively empty, the biliary sludge can start to accumulate.[2]

Gallbladder hepatization, which is biliary sludge filling the entire gallbladder, giving it an echogenicity similar to the liver (seen at left). The patient had a stone in the cystic duct.

Biliary sludge is typically diagnosed by CT scan or transabdominal ultrasonography.[1][2] Endoscopic ultrasonography is another more sensitive option. However, the gold standard is considered to be direct microscopy of aspirated gallbladder bile.[1][2] This method is much more sensitive, although it is less practical.[2]

For patients without symptoms, no treatment is recommended. If patients become symptomatic and/or develop complications, cholecystectomy is indicated.[1] For those who are poor surgical candidates, endoscopic sphincterotomy may be performed to reduce the risk of developing pancreatitis.[1]

The clinical course of biliary sludge can do one of three things: (1) it can resolve completely, (2) wax and wane, or (3) progress to gallstones.[1][2][3] If the biliary sludge has a cause (e.g. pregnancy), it oftentimes is resolved when the underlying cause is removed.[3]

The prevalence of biliary sludge is low in the general population.[2] It has been reported that the prevalence ranges from 0-0.20% in men and 0.18-0.27% in women.[2] However, in patients with certain conditions, the prevalence may be higher.[2]

• Biliary microlithiasis