Cholecystitis

Most people with gallstones do not have symptoms. People with cholecystitis most commonly have symptoms of biliary colic before developing cholecystitis. The pain becomes severe and constant in cholecystitis. Nausea is common and vomiting occurs in 75% of people with cholecystitis. In addition to abdominal pain, right shoulder pain can be present. Yellowing of the skin (jaundice) may occur but is often mild. Severe jaundice suggests another cause of symptoms such as choledocholithiasis. Complications A number of complications may occur from cholecystitis if not detected early or properly treated. Signs of complications include high fever, shock and jaundice. Complications include the following: • Gangrene • Gallbladder rupture • Empyema • Fistula formation and gallstone ileus • Rokitansky-Aschoff sinuses Gangrene and gallbladder rupture Cholecystitis causes the gallbladder to become distended and firm. Distension can lead to decreased blood flow to the gallbladder, causing tissue death and eventually gangrene. Once tissue has died, the gallbladder is at greatly increased risk of rupture (perforation), which can cause sharp pain. Rupture can also occur in cases of chronic cholecystitis. Rupture is a rare but serious complication that leads to abscess formation or peritonitis. Massive rupture of the gallbladder has a mortality rate of 30%. Empyema Untreated cholecystitis can lead to worsened inflammation and infected bile that can lead to a collection of pus inside the gallbladder, also known as empyema. The symptoms of empyema are similar to uncomplicated cholecystitis but greater severity: high fever, severe abdominal pain, more severely elevated white blood count. Fistula formation and gallstone ileus The inflammation of cholecystitis can lead to adhesions between the gallbladder and other parts of the gastrointestinal tract, most commonly the duodenum. These adhesions can lead to the formation of direct connections between the gallbladder and gastrointestinal tract, called fistulas. With these direct connections, gallstones can pass from the gallbladder to the intestines. Gallstones can get trapped in the gastrointestinal tract, most commonly at the connection between the small and large intestines (ileocecal valve). When a gallstone gets trapped, it can lead to an intestinal obstruction, called gallstone ileus, leading to abdominal pain, vomiting, constipation, and abdominal distension. ==Causes==

Cholecystitis occurs when the gallbladder becomes inflamed. The greatest risk factor for cholecystitis is gallstones. It is associated with many causes including vasculitis, chemotherapy, major trauma or burns. Ultrasonography or computed tomography often shows an immobile, enlarged gallbladder. It was first reported in the medical literature in 1976 by McCoy and colleagues. ==Mechanism==

Blockage of the cystic duct by a gallstone causes a buildup of bile in the gallbladder and increased pressure within the gallbladder. Concentrated bile, pressure, and sometimes bacterial infection irritate and damage the gallbladder wall, causing inflammation and swelling of the gallbladder. Inflammation and swelling of the gallbladder can reduce normal blood flow to areas of the gallbladder, which can lead to cell death due to inadequate oxygen. == Diagnosis ==

The diagnosis of cholecystitis is suggested by the history (abdominal pain, nausea, vomiting, fever) and physical examinations in addition to laboratory and ultrasonographic testing. Boas's sign, which is pain in the area below the right scapula, can be a symptom of acute cholecystitis. Blood tests In someone suspected of having cholecystitis, blood tests are performed for markers of inflammation (e.g. complete blood count, C-reactive protein), as well as bilirubin levels in order to assess for bile duct blockage. Imaging Right upper quadrant abdominal ultrasound is most commonly used to diagnose cholecystitis. Ultrasound findings suggestive of acute cholecystitis include gallstones, pericholecystic fluid (fluid surrounding the gallbladder), gallbladder wall thickening (wall thickness over 3 mm), dilation of the bile duct, and sonographic Murphy's sign. File:UOTW 30 - Ultrasound of the Week 2.webm|Significant gallbladder wall thickening File:Gross pathology of gallbladder carcinoma.jpg|Gross examination of gallbladder carcinoma, with a prominent nodule. File:Histopathology of gallbladder carcinoma.jpg|Histopathology of gallbladder carcinoma, with marked nuclear pleomorphism. File:Histopathology of eosinophilic cholecystitis.jpg|Histopathology of eosinophilic cholecystitis File:Gross pathology of cholesterolosis.jpg|Gross examination of gallbladder cholesterolosis, with yellow streaks of cholesterol deposition. File:Histopatholgoy of acute gangrenous cholecystitis.jpg|Histopathology of acute gangrenous cholecystitis, showing necrosis, neutrophils and partially sloughed off mucosa. Differential diagnosis Many other diagnoses can have similar symptoms as cholecystitis. Additionally the symptoms of chronic cholecystitis are commonly vague and can be mistaken for other diseases. These alternative diagnoses include but are not limited to: == Treatment ==

Surgery For most people with acute cholecystitis, the treatment of choice is surgical removal of the gallbladder, laparoscopic cholecystectomy. Laparoscopic cholecystectomy is performed using several small incisions located at various points across the abdomen. Several studies have demonstrated the superiority of laparoscopic cholecystectomy when compared to open cholecystectomy (using a large incision in the right upper abdomen under the rib cage). People undergoing laparoscopic surgery report less incisional pain postoperatively as well as having fewer long-term complications and less disability following the surgery. Additionally, laparoscopic surgery is associated with a lower rate of surgical site infection. During the days prior to laparoscopic surgery, studies showed that outcomes were better following early removal of the gallbladder, preferably within the first week. Early laparoscopic cholecystectomy (within 7 days of visiting a doctor with symptoms) as compared to delayed treatment (more than 6 weeks) may result in shorter hospital stays and a decreased risk of requiring an emergency procedure. For early cholecystectomy, the most common reason for conversion to open surgery is inflammation that hides Calot's triangle. For delayed surgery, the most common reason was fibrotic adhesions. Supportive measures may be instituted prior to surgery. These measures include fluid resuscitation. Intravenous opioids can be used for pain control. Antibiotics are often not needed. In cases of severe inflammation, shock, or if the person has higher risk for general anesthesia (required for cholecystectomy), an interventional radiologist may insert a percutaneous drainage catheter into the gallbladder (percutaneous cholecystostomy tube) and treat the person with antibiotics until the acute inflammation resolves. A cholecystectomy may then be warranted if the person's condition improves. Homeopathic approaches to treating cholecystitis have not been validated by evidence and should not be used in place of surgery. == Epidemiology ==

Cholecystitis accounts for 3–10% of cases of abdominal pain worldwide. Cholecystitis caused an estimated 651,829 emergency department visits and 389,180 hospital admissions in the US in 2012. The 2012 US mortality rate was 0.7 per 100,000 people. The frequency of cholecystitis is highest in people age 50–69 years old. ==References==