Acute Cholangitis

Acute cholangitis is a bacterial infection superimposed on an obstruction of the biliary tree most commonly from a gallstone, but it may be associated with neoplasm or stricture. The classic triad of findings is right upper quadrant (RUQ) pain, fever, and jaundice. A pentad may also be seen, in which mental status changes and sepsis are added to the triad. ^{[1, 2]}

A spectrum of cholangitis exists, ranging from mild symptoms to fulminant overwhelming sepsis. Thus, therapeutic options for patient management include broad-spectrum antibiotics and, potentially, emergency decompression of the biliary tree. ^[3]

The main factors in the pathogenesis of acute cholangitis are biliary tract obstruction, elevated intraluminal pressure, and infection of bile. A biliary system that is colonized by bacteria but is unobstructed, typically does not result in cholangitis. It is believed that biliary obstruction diminishes host antibacterial defenses, causes immune dysfunction, and subsequently increases small bowel bacterial colonization. Although the exact mechanism is unclear, it is believed that bacteria gain access to the biliary tree by retrograde ascent from the duodenum or from portal venous blood. As a result, infection ascends into the hepatic ducts, causing serious infection. Increased biliary pressure pushes the infection into the biliary canaliculi, hepatic veins, and perihepatic lymphatics, leading to bacteremia (25-40%). The infection can be suppurative in the biliary tract.

The bile is normally sterile. In the presence of gallbladder or common bile duct stones, however, the incidence of bactibilia increases. The most common organisms isolated in bile are Escherichia coli (27%), Klebsiella species (16%), Enterococcus species (15%), Streptococcus species (8%), Enterobacter species (7%), and Pseudomonas aeruginosa (7%). Organisms isolated from blood cultures are similar to those found in the bile. The most common pathogens isolated in blood cultures are E coli (59%), Klebsiella species (16%), Pseudomonas aeruginosa (5%), and Enterococcus species (4%). In addition, polymicrobial infection is commonly found in bile cultures (30-87%) and less frequent in blood cultures (6-16%). For related pathophysiology, please see Cholelithiasis and Cholecystitis and Biliary Colic.

Primary sclerosing cholangitis is a chronic liver disease that is thought to be due to an autoimmune mechanism. ^[4] It is characterized by inflammation and fibrosis of the intrahepatic and extrahepatic bile ducts. This condition ultimately leads to portal hypertension and cirrhosis of the liver with the only definitive treatment being a liver transplant. ^[5] For more on this condition, please see Primary Sclerosing Cholangitis.

In Western countries, choledocholithiasis is the most common cause of acute cholangitis, followed by ERCP and tumors.

Any condition that leads to stasis or obstruction of bile in the common bile duct (CBD) , including benign or malignant stricture, parasitic infection, or extrinsic compression by the pancreas, can result in bacterial infection and cholangitis. Partial obstruction is associated with a higher rate of infection than complete obstruction.

Common bile duct stones

CBD stones predispose patients to cholangitis. Approximately 10-15% of patients with cholecystitis have CBD stones.

Approximately 1% of patients post cholecystectomy have retained CBD stones. Most CBD stones are immediately symptomatic, although some remain asymptomatic for years.

Some CBD stones are formed primarily rather than secondarily to gallstones.

Obstructive tumors

Obstructive tumors cause cholangitis. Partial obstruction is associated with an increased rate of infection compared with that of complete neoplastic obstruction. Obstructive tumors include the following:

• Pancreatic cancer

• Cholangiocarcinoma ^[6]

• Ampullary cancer

• Porta hepatis tumors or metastasis

Other causes

Additional causes of cholangitis include the following:

• Strictures or stenosis

• Endoscopic manipulation of the CBD

• Choledochocele ^[7]

• Sclerosing cholangitis (from biliary sclerosis)

• AIDS cholangiopathy

• Ascaris lumbricoidesinfections

United States data

Cholangitis is relatively uncommon. It occurs in association with other diseases that cause biliary obstruction and bactibilia (eg, after endoscopic retrograde cholangiopancreatography [ERCP], 1-3% of patients develop cholangitis). Risk is increased if dye is injected retrograde.

International data

Recurrent pyogenic cholangitis, sometimes referred to as Oriental cholangiohepatitis, is endemic to Southeast Asia. It is characterized by multiple occurrences of biliary tract infection, intrahepatic and extrahepatic biliary stone formation, hepatic abscesses, and dilatation and stricturing of the intrahepatic and extrahepatic bile duct. ^[8] For more on this condition, please refer to the Recurrent Pyogenic Cholangitis article.

Race-related demographics

Cholangitis frequently occurs secondary to a gallstone obstructing the common bile duct. Therefore, it carries the same risk factors as that of cholelithiasis.

Prevalence of gallstones is highest in fair-skinned people of Northern European descent as well as in Hispanic populations, Native Americans, and Pima Indians.

In addition, certain Asian populations and inhabitants of countries where intestinal parasites are common are also at increased risk. Asians are more likely to have primary stones due to chronic biliary infections, parasites, bile stasis, and biliary strictures. Recurrent pyogenic cholangitis (Oriental cholangiohepatitis) rarely is observed in the United States.

Black individuals with sickle cell disease are at increased risk.

Sex- and age-related demographics

Although gallstones are more common in women than in men, the male-to-female ratio is equal in cholangitis.

Elderly patients are more likely to progress from asymptomatic gallstones to serious complications of gallstones and cholangitis.

Suspect cholangitis in older patients presenting with sepsis and mental status changes. Elderly patients are more prone to gallstones and common bile duct stones and, therefore, cholangitis.(ref26)

The median age at presentation is between 50 and 60 years.

The prognosis depends on several factors, including the following ^[9] :

• Early recognition and treatment of cholangitis

• Response to therapy

• Underlying medical conditions of the patient

Mortality rate ranges from 5-10%, with a higher mortality rate in patients who require emergency decompression or surgery. Early endoscopic retrograde cholangiopancreatography (ERCP) for acute cholangitis within 24 hours appears to be associated with a lower 30-day mortality. ^[10]

In patients responding to antibiotic therapy, the prognosis is good.

Schneider et al proposed a risk prediction model for in-hospital mortality in patients with acute cholangitis using 22 predictors and the Tokyo criteria to stratify them into high- and low-risk mortality groups and then into different management groups. ^[11] In univariate analysis, organ failure had the strongest association with mortality—with mental confusion, hypotension requiring catecholamines, Quick value below 50%, serum creatinine level above 2 mg/dL, and a platelet count below 100,000/mm³ as prognostic factors contributing to organ failure. Patients classified as low risk for mortality would be considered for elective biliary drainage, whereas those considered to be at high risk for mortality would undergo urgent biliary drainage. ^[11]

Schwed et al indicate that leukocytosis greater than 20,000 cells/μL and total bilirubin level above 10 mg/dL, but not timing of ERCP, are independent prognostic factors for adverse outcomes. ^[12] In a separate study, Tabibian et al did not find adverse outcomes from weekend admission and weekend endoscopic retrograde cholangiography (ERC) on patients with acute cholangitis admitted to a tertiary care center. ^[13]

Morbidity/mortality

Mortality from cholangitis is high due to the predisposition in people with underlying disease. Historically, the mortality rate was 100%. With the advent of endoscopic retrograde cholangiography, therapeutic endoscopic sphincterotomy, stone extraction, and biliary stenting, the mortality rate has significantly declined to approximately 5-10%.

The following patient characteristics are associated with higher morbidity and mortality rates:

• Hypotension

• Acute renal failure

• Liver abscess

• Cirrhosis

• Inflammatory bowel disease

• High malignant strictures

• Radiologic cholangitis: Post percutaneous transhepatic cholangiography

• Female gender

• Age older than 50 years

• Failure to respond to antibiotics and conservative therapy ^[14]

Advanced age, concurrent medical problems, and delay in decompression increase the emergent operative mortality rate (17-40%).

The mortality rate of elective surgery after medical stabilization is significantly less (approximately 3%).

In the past, suppurative cholangitis was thought to have increased morbidity; however, prospective studies have not found this to be true.

Complications

Patients are increasingly likely to have complications with greater degrees of illness, as follows:

• Liver failure, hepatic abscesses, and microabscesses

• Bacteremia (25-40%); gram-negative sepsis

• Acute renal failure

Catheter-related problems in patients treated with percutaneous or endoscopic drainage include the following:

• Bleeding (intra-abdominally or percutaneously)

• Catheter-related sepsis

• Fistulae

• Bile leak (intraperitoneally or percutaneously)