what is cbd obstruction

December 15, 2021 By admin Off

Risk factors for bile duct obstruction include:

When left untreated, biliary duct obstruction can lead to possible complications such as liver disease like biliary cirrhosis, infections, sepsis, the build-up of bilirubin in the bloodstream, and inflammation of the gallbladder.

The main objective of the treatment is to relieve the bile duct blockage. Depending on the underlying cause of the blockage, your doctor may suggest several treatment options. Gallstones may be removed from the bile duct using endoscopic retrograde cholangiopancreatography (ERCP). The doctor may even recommend a cholecystectomy to remove the gallbladder to prevent recurring blockages in the future. If the obstruction is formed because of cancer, surgical procedures may be suggested to stretch and drain the ducts. This will be done using an endoscope or by dilating the duct to widen it.

What Are the Symptoms of Biliary Obstruction?

Also known as bile duct obstruction, biliary obstruction is a blockage in one of the ducts that transport bile from the liver to the small intestine through the gallbladder. Bile is a liquid produced by the liver that contains bile salts, cholesterol, and waste products like bilirubin that help digest fats. From the liver, the bile passes via a network of bile ducts (also referred to as biliary tree) and accumulates in the gallbladder. After you have eaten a meal, the bile is released from the gallbladder into the small intestine to help digest food and break down fat.

Symptoms of bile duct obstruction will vary – they may be severe and abrupt or may appear slowly over the years. Common symptoms experienced by patients include: Jaundice (yellowing of the skin or eyes) due to the build-up of bilirubin in the bloodstream.

While most causes of biliary obstruction are usually unpreventable, experts believe that making a few changes in your diet and weight can make you less susceptible to developing this condition. Add more fiber to your diet, and lower your intake of saturated fats, cholesterol, and sugar, to prevent gallstones. With the help of exercise and a nutritious diet, work towards achieving a healthy weight. To learn more about biliary obstructions and its preventive measures, contact us.

Biliary obstruction occurs when one of the bile ducts becomes blocked, leading to the bile collecting in the liver and bilirubin shooting up in the bloodstream. The following are a few potential causes resulting in biliary obstruction:

Dr. Madhu Prasad has over 30+ years of experience working as a general surgeon and surgical oncologist and providing the highest level of care in Anchorage, Alaska. He believes in providing quality care to patients and their families. Inspired by compassion and humanism, Dr. Prasad and his team work for the well-being of their patients.

What Are the Complications Related to Biliary Duct Obstruction?

What Treatments Are Available for Biliary Obstruction?

Intrahepatic cholestasis generally occurs at the level of the hepatocyte or biliary canalicular membrane. Causes include hepatocellular disease (eg, viral hepatitis, drug-induced hepatitis), drug-induced cholestasis, biliary cirrhosis, and alcoholic liver disease. In hepatocellular disease, interference in the three major steps of bilirubin metabolism, ie, uptake, conjugation, and excretion, usually occurs. Excretion is the rate-limiting step and is usually impaired to the greatest extent. As a result, conjugated bilirubin predominates in the serum.

Biliary obstruction refers to the blockage of any duct that carries bile from the liver to the gallbladder or from the gallbladder to the small intestine. This can occur at various levels within the biliary system. The major signs and symptoms of biliary obstruction result directly from the accumulation of bilirubin and bile salts in the blood and the failure of bile to reach its proper destination.

Accumulation of bilirubin in the bloodstream and subsequent deposition in the skin causes jaundice (icterus). Conjunctival icterus is generally a more sensitive sign of hyperbilirubinemia than generalized jaundice. Total serum bilirubin values are normally 0.2-1.2 mg/dL. Jaundice may not be clinically recognizable until levels are at least 3 mg/dL. [2] Urine bilirubin is normally absent. When it is present, only conjugated bilirubin is passed into the urine as it is water soluble. This may be evidenced by dark-colored urine seen in patients with obstructive jaundice or jaundice due to hepatocellular injury. However, reagent strips are very sensitive to bilirubin, detecting as little as 0.05 mg/dL. Thus, urine bilirubin may be found before serum bilirubin reaches levels high enough to cause clinical jaundice.

The clinical setting of cholestasis or failure of biliary flow may be due to biliary obstruction by mechanical means or by metabolic factors in the hepatic cells. For the sake of simplicity, the primary focus of this article is mechanical causes of biliary obstruction, further separating them into intrahepatic and extrahepatic causes. The discussion of intracellular/metabolic causes of cholestasis is very complex, the pathogenesis of which is not always clearly defined. Therefore, these causes are mentioned but are not discussed in detail.

Extrahepatic obstruction to the flow of bile may occur within the ducts or secondary to external compression. Overall, gallstones are the most common cause of biliary obstruction. Other causes of blockage within the ducts include malignancy, infection, and biliary cirrhosis. External compression of the ducts may occur secondary to inflammation (eg, pancreatitis) and malignancy. Regardless of the cause, the physical obstruction causes a predominantly conjugated hyperbilirubinemia.

Pathophysiology.

For patient education resources, see the Digestive Disorders Center and Cholesterol Center, as well as Gallstones and Cirrhosis.

Disorders of the biliary tract affect a significant portion of the worldwide population, and the overwhelming majority of cases are attributable to cholelithiasis (gallstones). In the United States, 20% of persons older than 65 years have gallstones and 1 million newly diagnosed cases of gallstones are reported each year.

To better understand these disorders, a brief discussion of the normal structure and function of the biliary tree is needed. Bile is the exocrine secretion of the liver and is produced continuously by hepatocytes. It contains cholesterol and waste products, such as bilirubin and bile salts, which aid in the digestion of fats. Half the bile produced runs directly from the liver into the duodenum via a system of ducts, ultimately draining into the common bile duct (CBD). The remaining 50% is stored in the gallbladder. In response to a meal, this bile is released from the gallbladder via the cystic duct, which joins the hepatic ducts from the liver to form the CBD. The CBD runs in the hepatodudoenal ligament and then courses through the head of the pancreas for approximately 2 cm; it joins the terminal part of the pancreatic duct to form the ampulla of Vater before passing through the papilla of Vater into the duodenum. [1]

The lack of bilirubin in the intestinal tract is responsible for the pale stools typically associated with biliary obstruction. The cause of itching (pruritus) associated with biliary obstruction is not clear. Some believe it may be related to the accumulation of bile acids/bile salts in the skin. Others suggest it may be related to the release of endogenous opioids.

The incidence of gallstones causing biliary obstruction is approximately 5 in 1000 people, whereas 10% to 15% of the adult U.S. population will develop gallstones in their lifetime.[6] Gall stones or Cholelithiasis, including gall bladder sludge formation, is the precursor of choledocholithiasis, where gall stones pass through the cystic duct and get lodged into the common hepatic ducts causing an obstruction. Between 10 and 15% of patients with gall stones are also noted to have common bile duct stones at diagnosis.[7] 

A careful history of symptom duration if gradual or acute onset, accompanying symptoms like weight loss, loss of appetite, nausea/vomiting is important. Similarly, any right-sided abdominal pain along with severity and radiation is important to know. History of diarrhea, hematochezia, and upper GI bleeding symptoms is also relevant to diagnosing the underlying process. It is imperative to know any pertinent personal and family history like bile duct or pancreatic malignancy, inflammatory bowel disease, or primary liver disease. A careful review of social history related to current and former smoking, alcohol use, and drug abuse is important. Similarly, travel history to parasitic endemic regions is of value in determining the etiology of biliary obstruction. A careful review of medication history can sometimes be of great significance in determining intrahepatic cholestasis vs. extrahepatic biliary obstruction.

Biliary obstruction is generally referred to as blockage of the extrahepatic biliary system. Biliary obstruction can occur anywhere along this path and can lead to serious complications such as hepatic dysfunction, renal failure, nutritional deficiencies, bleeding problems, and infections.[2]

Biliary obstruction can have very varied presentation depending on the underlying etiology. It usually presents as jaundice with clay-colored or acholic stools and dark urine. Patients can have pruritis with chronic biliary obstruction. Patients depending on underlying etiology can have right upper quadrant abdominal pain, fever, nausea and vomiting, and weight loss. The onset of these symptoms can be variable ranging from acute development of symptoms to over months.

Women are at greater risk of developing gallstones than men and hence increased risk for choledocholithiasis. This is likely secondary to estrogen increasing hepatic uptake of cholesterol, which increases bile production and some degree of cholestasis.[8]

Etiology.

StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-.

A detailed and thorough physical exam is of paramount importance. It is imperative to check baseline vital signs especially checking for fever and elevated heart rate. A general physical exam to assess for any distress, pallor, skin jaundice, scleral icterus, palmer erythema, and signs of malnutrition is important. A detailed abdominal examination to assess for right upper quadrant tenderness (Murphy’s sign), hepatomegaly and splenomegaly, presence of ascites, any palpable mass, stigmata of cirrhosis (caput-medusae) is very crucial for diagnosis. A cardiac exam to assess for signs of congestive heart failure with jugular venous distension and displacement of heart sounds can be very important to determine underlying etiology. Similarly, a pulmonary exam to assess for pleural effusions, determining one-sided or bilateral, helps determine etiology. Assessment for lymphadenopathy in left supraclavicular lymph nodes and other neck lymph nodes can provide helpful information. Looking for lower extremity edema is also important.

Last Update: September 28, 2021 .

Gallstones are the most common cause of biliary obstruction in Hispanics, Northern Europeans, and Native Americans. Northern Native Americans have the highest reported rates of cholelithiasis at 64% for females and 29% for males. Asian and African Americans have an intermediate prevalence of cholelithiasis, with 13.9% of women and 5.3% in men. The lowest prevalence of cholelithiasis is in sub-Saharan Black African, with an overall prevalence of less than 5%. White race North Americans have an overall prevalence of cholelithiasis of 16.6% and 8.6% in females and males, respectively.[9][8]

Extrahepatic biliary obstruction can also lead to chronic changes to liver histology over prolonged obstruction of bile ducts. However, the etiology of biliary obstruction can be determined through histology from brush cytology or tissue biopsy samples obtained during various procedures like endoscopic retrograde cholangiopancreatography (ERCP), percutaneous transhepatic cholangiogram (PTC), or endoscopic ultrasound (EUS) directed biopsy. Sometimes a tissue sample is imperative for accurate diagnosis, especially for the workup for stricture of the biliary tract noted on non-invasive imaging. 

Extrahepatic biliary obstruction, which is the scope of this article, can be divided into various benign and malignant etiologies. These include choledocholithiasis (gall stones in the common bile duct), choledochal cysts (dilation/cysts of bile ducts), Mirizzi syndrome (gall stones in cystic duct pressing on bile duct), benign structuring diseases like Primary sclerosing cholangitis (PSC), fibrotic strictures from gall stone passage or iatrogenic strictures from bile duct cannulation. Neoplastic stricture diseases causing biliary obstruction can include cholangiocarcinoma (bile duct cancer), pancreatic head cancer leading to distal common bile duct stricture, and ampullary carcinoma or adenoma.  Other etiologies of biliary obstruction can include infectious diseases like parasitic cholangiopathy ( Clonorchis sinensis,  Ascaris lumbricoides) causing intra- or extrahepatic obstruction to bile flow, inflammatory and autoimmune diseases like AIDS cholangiopathy, and autoimmune cholangiopathy.[6]

Ethan M. Coucke ; Hina Akbar ; Arslan Kahloon ; Peter P. Lopez .

Intrahepatic cholestasis can be diagnosed with a percutaneous or transjugular liver biopsy and is not covered in detail under this topic.

In developed countries, choledocholithiasis secondary to cholesterol stones is the most common cause of biliary obstruction, whereas brown pigment stones from infectious etiologies or hemolysis are the most common etiology in Asia. Other etiologies like recurrent pyogenic cholangiohepatitis is characterized by recurrent bacterial cholangitis, dilatation, and stricture of the biliary tree, the presence of calculi within the intrahepatic bile ducts, and an increased risk for cholangiocarcinoma is common in Asia but rare in the west. Gallbladder malignancy is more common in Central and South America, Central and Eastern Europe, the northern Indian subcontinent, and East Asia.[10][11][8] 

History and Physical.

Biliary obstruction refers to the impairment of bile flow from the liver to the small intestine due to blockage of the biliary duct system. Bile obstruction affects a large portion of the population around the world with significant morbidity and mortality. The most common etiology of biliary obstruction is gallstones causing common bile duct obstruction, which manifests as pain, nausea/vomiting, and jaundice. This activity describes the etiology, pathophysiology, evaluation, and management of biliary obstruction and highlights the interprofessional team’s role in caring for affected patients.

Disruption in the bile flow due to impairment of the intrahepatic biliary system is generally referred to as cholestasis. Cholestasis can present as abnormalities in serum hepatic enzymes such as elevated bilirubin, alkaline phosphatase levels and can lead to jaundice and pruritis.

Physical Examination.

Biliary obstruction is common and affects a large portion of the world population, causing significant morbidity and mortality. The most common etiology of biliary obstruction is choledocholithiasis or gallstones, causing extrahepatic bile duct blockage. The most serious manifestation of this is the development of infection in the bile ducts called cholangitis, which can be fatal if not treated promptly.[3] 

History and Presentation.

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.

Affiliations.

Bile formed in the liver flows through the right and left hepatic ducts into the common hepatic duct. The common hepatic duct then joins the cystic duct arising from the gallbladder to form the common bile duct. The common bile duct then joins the pancreatic duct through its course within the head of the pancreas before opening into the duodenum through the major papilla or ampulla. The majority of the bile flows into the gall bladder through the cystic duct, where it is concentrated and temporarily stored, while the rest of the bile flows through the common bile duct into the duodenum through the sphincter of Oddi. The flow of bile into the duodenum is regulated by the release of the hormone Cholecystokinin (CCK) from the duodenum, which controls the release of stored bile from the gallbladder and the relaxation of the sphincter of Oddi.

Biliary obstruction can   be divided into intrahepatic and extrahepatic etiologies. As described above, intrahepatic biliary obstruction is generally called cholestasis and not covered here in detail as it is not the scope of this topic. Briefly, intrahepatic cholestasis can be from several disease processes, including certain forms of hepatitis (viral infections, alcohol), drug-induced liver injury (antibiotics, acetaminophen, anti-epileptics, anti-arrhythmic), primary biliary cholangitis, primary sclerosing cholangitis, and infiltrative diseases (sarcoidosis, tumors, abscess, and cysts).[4][5] 

Biliary obstruction commonly refers to blockage of the bile duct system leading to impaired bile flow from the liver into the intestinal tract. Bile is a substance that contains bile salts, bilirubin, and cholesterol and is continuously synthesized in the liver hepatocytes. Bile is then transported via the bile ducts into the second portion of the duodenum to assist with the metabolism of fats.[1]

Work up for biliary obstruction includes routine   labs and some dedicated labs, including: