Cholecystitis: causes, symptoms, and clinical management

Cholecystitis

Biliary colic and cholecystitis are in the spectrum of gallbladder disease, ranging from asymptomatic gallstones to biliary colic, cholecystitis, choledocholithiasis, and cholangitis (Santen pp). When gallstones temporarily obstruct the cystic duct or pass through into the common bile duct, gallstones become symptomatic and biliary colic develops, however, if the cystic duct or common bile duct becomes obstructed for hours or gallstones irritate the gallbladder, then cholecystitis develops, and when the stones become lodged in the common bile duct, choledocholithiasis occurs, resulting in possible cholangitis and ascending infections (Santen pp).

Cholecystitis is an inflammation of the gallbladder caused by obstruction, usually a gallstone, of the cystic duct, and the inflammation may be sterile or bacterial and the obstruction may be acalculous or caused by sludge (Santen pp). Bacterial infection is believed to be a consequence, not a cause, of cholecystitis, approximately 75% of bile cultures are positive, with the most common organisms being Escherichia coli, Klebsiella species, and enterococci (Santen pp). Common bile duct stones, choledocholithiasis (10%), "are either secondary (from the gallbladder) or primary (formed in bile ducts)" (Santen pp).

Acute cholecystitis most often caused by a gallstone that cannot pass through the bile duct (Cholecystitis pp). Pain is felt in the right upper part of the stomach, and there may be nausea, vomiting, belching, and intestinal gas, flatulence (Cholecystitis pp). Diagnosis usually made with x-rays, is useful in ruling out appendicitis, intestinal obstruction, peptic ulcer, and other upper stomach disorders, and surgery is the usual treatment (Cholecystitis pp). Chronic cholecystitis is the more common type and has a slower beginning, with pain, often felt at night following a fatty meal (Cholecystitis pp). Complications include gallstones, disease of the pancreas, and cancerous growth (carcinoma) of the gallbladder, and usually corrected by surgery (Cholecystitis pp).

In roughly 90% of cases, acute cholecystitis is caused by gallstones in the gallbladder, which obstruct the duct leading from the gallbladder to the common bile duct, which drains into the intestine, however, severe illness, alcohol abuse, and, although rare, tumors of the gallbladder may also be the cause (Kato pp). The trapped bile becomes concentrated and causes irritation and pressure build-up in the gallbladder, which can lead to bacterial infection and perforation (Kato pp). Attacks may follow a large or fatty meal, and occur more frequently in women than men, and becomes more common with age in both sexes (Kato pp). Native Americans have a higher incidence of gallstones (Kato pp).

A doctor's examination of the abdomen by touch, palpation, may reveal tenderness, and test that detect the presence of gallstones or inflammation include, abdominal ultrasound, abdominal CT scan, abdominal x-ray, oral cholecystogram, gallbladder radionuclide scan, and a CBC shows infection by an elevated white blood cell count (Kato pp).

Although cholecystitis may clear up on its own, surgery to remove the gallbladder, cholecystectomy, is usually needed when inflammation persists or recurs and is performed as soon as possible after the onset of cholecystitis, unless the patient is very ill, or if the inflammation is thought to have been present for many days (Kato pp). In very ill patients, occasionally, a tube may be placed through the skin to drain the gallbladder until the patient recovers from the acute illness and is fit to undergo surgery (Kato pp). Cholecystectomy is usually performed using a laparoscope, in which small (1 cm) incisions are made in the abdomen, and instruments and a fiberoptic camera are passed through (Kato pp). Laparoscopic cholecystectomy is performed using these small instruments while the surgeon watches the image on a video monitor, and results in less pain and shorter hospitalization times than an open operation (Kato pp). However, if there is a significant amount of inflammation, difficulty defining the anatomy, or if significant bleeding occurs, a laparoscopic operation may be converted to an open operation, performed through a larger incision (Kato pp). Moreover, if gangrene, perforation, pancreatitis, or inflammation of the common bile occurs, emergency surgery may be necessary (Kato pp).

Nonsurgical treatment consists of pain control, antibiotics to eliminate the infection, and a low-fat diet (Kato pp). Removal of the gallbladder and the contained gallstones will prevent further attacks of cholecystitis, and reducing the fat content in the diet if prone to attacks (Kato pp).

Chronic cholecystitis is caused by repeated mild attacks of acute cholecystitis and leads to thickening of the walls of the gallbladder (Stone pp). The gallbladder begins to shrink and eventually loses the ability to perform its function, which is concentrating and storing bile (Stone pp). The consumption of fatty foods may aggravate the symptoms of cholecystitis, because bile is needed to digest such foods (Stone pp). It occurs more often in women than men and incidences increase after the age of forty (Stone pp). Risk factors include the presence of gallstones and a history of acute cholecystitis (Stone pp). Patients who are poor candidates for surgery due to other diseases or conditions, may benefit from methods to dissolve gallstones, and symptoms can be managed by low-fat diet, weight reduction, and antacids, acid-suppressing and anticholinergic medications may be helpful (Stone pp).

Prevalence is affected by many factors, including race, ethnicity, gender, age, medical problems, and fertility (Santen pp). Roughly 20% of adults in the United States have gallstones, and each year, only 1-3% of people with stones develop symptoms of gallstones (Santen pp). Populations in Hispanic or northern European countries are more likely to have stones, while African-Americans are at decreased risk unless they have a hematologic reason, such as sickle cell anemia (Santen pp). Asians with stones are more likely than other populations to have pigmented stones, and in elderly Pima Indians, incidence of gallstones is approximately 75% (Santen pp). The phrase "fair, female, fat, and fertile" summarizes the major risk factors for development of gallstones, and although gallstones and cholecystitis are more common in women, men with gallstones are more likely to develop cholecystitis than women with gallstones (Santen pp). Whether pregnant women or women who have had multiple pregnancies are more likely to develop stones or are simply more symptomatic with stones is unknown (Santen pp). There is belief that some oral contraceptives or estrogen replacement therapy may increase the risk of gallstones, and elderly patients are more likely to go from asymptomatic gallstones to serious complications of gallstones without gallbladder colic (Santen pp). Children are more likely than adults to have acalculous gallstones, and the stones are more likely pigmented stones from hemolytic diseases, such as sickle cell diseases, spherocytosis, and G-6-PD deficiency, or chronic diseases, such as total parenteral nutrition, burns, and trauma (Santen pp). Teenagers have the same etiologies of gallstones as adults, with a higher incidence in females and during pregnancy (Santen pp).

Asymtomatic gallstones result in morbidity and mortality when they become symptomatic, with mortality rate as high as 15% in immunocompromised patients (Santen pp). Complicated cholecystitis, such as gangrene and empyema of the gallbladder, has 25% mortality, while perforation of gallbladder occurs in 3-15% of patients with cholecystitis and with 60% mortality (Santen pp).