Acute Calculous Cholecystitis

Peptic Ulcer Bleeding from Sun YaiCheng

Acute Calculous Cholecystitis
NEJM June 26, 2008;358;26:2804-11

Pathogenesis

• With inflammation, the gallbladder becomes enlarged, tense, and reddened, and wall thickening and an exudate of peri-cholecystic fluid may develop.
• Enterobacteriaceae family or with enterococci or anerobes occurs in the majority of patients.
• The wall of the gallbladder may undergo necrosis and gangrene (gangrenous cholecystitis).
• Bacterial super-infection with gas-forming organisms may lead to gas in the wall or lumen of the gallbladder (emphysematous cholecystitis).

Diagnosis

• Murphy's sign — the arrest of inspiration while palpating the gallbladder during a deep breath.
• Systemic sepsis and organ failure → gangrenous or emphysematous cholecystitis.
• Fever, elevation in the WBC and CRP.
• Elevated serum amylase level →concomitant gallstone pancreatitis or gangrenous cholecystitis.
• In elderly patients, delays in diagnosis are common, the only symptoms may be a change in mental status or decreased food intake, and physical examination and laboratory indexes may be normal.

Imaging

• Ultrasonography detects cholelithiasis in about 98% of patients.
• Acute calculous cholecystitis is diagnosed radiologically by the concomitant presence of thickening of the gallbladder wall ( >5 mm), peri-cholecystic fluid, or direct tenderness when the probe is pushed against the gallbladder (ultrasonographic Murphy's sign).

• Hepatobiliary scintigraphy involves intravenous injection of technetium-labeled analogues of iminodiacetic acid, which are excreted into bile. The absence of gallbladder filling within 60 minutes after the administration of tracer indicates obstruction of the cystic duct and has a sensitivity of 80 to 90% for acute cholecystitis.
• The " rim sign " is a blush of increased pericholecystic radioactivity, which is present in about 30% of patients with acute cholecystitis and in about 60% with acute gangrenous cholecystitis.

Treatment

1. Timing of Cholecystectomy
2. Antibiotic Therapy
3. Percutaneous Cholecystostomy

1. Timing of Cholecystectomy

• Cholecystectomy can be performed by laparotomy or by laparoscopy, either at the time of the initial attack (early treatment) or 2 to 3 months after the initial attack has subsided (delayed treatment).
• “ Early" has been variably defined as anywhere from 24 hours to 7 days after either the onset of symptoms or the time of diagnosis.
• If delayed, or "conservative," treatment is selected, patients are treated during the acute phase with antibiotics and intravenous fluids and NPO.
• Early laparoscopic cholecystectomy is considered the treatment of choice for most patients.
• Predictors of the need for conversion include

• WBC > 18000
• duration of symptoms of more than a range of 72 to 96 hrs
• age over 60 years

2. Antibiotic Therapy

• The guidelines of the Infectious Diseases Society of America recommend that antimicrobial therapy be instituted if infection is suspected on the basis of laboratory and clinical findings (WBC > 12500/mm3 or temperature > 38.5°C) and radiographic findings (e.g., air in the gallbladder or gallbladder wall).
• Antibiotics coverage against micro-organisms in the Enterobacteriaceae family (e.g., 2° cephalosporin or a combination of a quinolone and metronidazole); activity against enterococci is not required.
• Antibiotics are also recommended for routine use in patients who are elderly or have diabetes or immunodeficiency and for prophylaxis in patients undergoing cholecystectomy to reduce septic complications even when infection is not suspected.

3. Percutaneous Cholecystostomy

• Percutaneous cholecystostomy is often used when the patient presents with sepsis (severe acute cholecystitis, according to the Tokyo guidelines) and in cases in which conservative treatment alone fails, especially in patients who are poor candidates for surgery.

Guidelines

• Mild acute cholecystitis : early laparoscopic cholecystectomy is recommended. 

• Moderate acute cholecystitis : either early or delayed cholecystectomy may be selected but that early laparoscopic cholecystectomy should be performed only by a highly experienced surgeon and promptly terminated by conversion to open cholecystostomy if operative conditions make anatomical identification difficult. 

• Severe acute cholecystitis : initial conservative management with antibiotics is recommended, preferably in a high-acuity setting, with the use of percutaneous cholecystostomy as needed; surgery is reserved for patients in whom this treatment fails.