It is the inflammation of the gallbladder that occurs most commonly due to an obstruction of the cystic duct by gallstones that originate in the gallbladder (cholelithiasis).
Uncomplicated cholecystitis has an excellent prognosis; the development of complications such as perforation or gangrene makes the prognosis less favorable.
Signs and symptoms of acute cholecystitis
The most frequent symptom of acute cholecystitis is upper abdominal pain. The following characteristics can be reported: Signs of peritoneal irritation may be present, and pain may radiate to the right shoulder or scapula. In addition, pain often begins in the epigastric region and is then located in the right upper quadrant (RUQ). Nausea and vomiting usually occur, and the presence of fever may be noted.
Cholecystitis can occur differently in special populations, such as:
The elderly (especially diabetics) may present initially vague symptoms and without many key historical and physical findings (eg, pain and fever) with localized sensitivity, being the only sign they present; but later they can advance to complicated cholecystitis, quickly and without warning. In children it can occur without many of the classic findings.
People at increased risk of acute cholecystitis include those with sickle cell disease, severe disease, hemolytic conditions or congenital and biliary abnormalities. The physical examination may reveal the following: Fever, tachycardia and tenderness in the RUQ or epigastric region, often with guard or rebound, as well as a palpable gallbladder or fullness of the RUQ (30-40% of patients); Jaundice (15% of patients). The truth is that the absence of physical findings does not rule out the diagnosis of cholecystitis.
Diagnosis of acute cholecystitis
Laboratory tests at the time of diagnosis of acute cholecystitis are not always reliable, but the following findings may be useful:
- You can see leukocytosis with a shift to the left,
- Levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) may be elevated in cholecystitis or with common bile duct obstruction (CBD)
- Bilirubin and alkaline phosphatase assays may reveal evidence of CBD obstruction
- Amylase / lipase tests are used to evaluate pancreatitis; as well as amylase may also be slightly elevated in acute cholecystitis.
- The level of alkaline phosphatase may be elevated (25% of patients with cholecystitis)
The modalities of diagnostic imaging that can be considered to verify the presence of acute cholecystitis are the following:
Computed tomography (CT)
Magnetic resonance imaging (MRI)
Endoscopic retrograde cholangiopancreatography (ERCP)
Recommendations of the American College of Radiology (ACR), regarding imaging in relation to acute cholecystitis
Ultrasound is the preferred initial imaging test for the diagnosis of acute cholecystitis.
CT is a secondary imaging test that can identify extrabiliary disorders and complications of acute cholecystitis
CT with intravenous contrast (IV) is useful in the diagnosis of acute cholecystitis in patients with nonspecific abdominal pain
MRI, often with IV gadolinium-based contrast medium, is also a possible secondary option to confirm the diagnosis of acute cholecystitis
Magnetic resonance imaging without contrast is useful to eliminate radiation exposure in pregnant women when ultrasound has not given a clear diagnosis
Contrast agents should not be used in dialysis patients unless absolutely necessary
Administration of treatment for acute cholecystitis
The treatment of acute cholecystitis depends on the severity of the condition and the presence or absence of complications. In acute cholecystitis, initial treatment includes bowel rest, IV hydration, correction of electrolyte abnormalities, analgesics, and intravenous antibiotics. Options include the following: Ampicillin-sulbactam, or meropenem; In severe cases of risk to life, imipenem-cilastatin is administered.
Alternative regimens – Third generation cephalosporin plus metronidazole
Due to the rapid progression from acute acalculous cholecystitis to gangrene and perforation, early recognition and intervention are necessary. Supportive medical care should include the restoration of hemodynamic stability and antibiotic coverage of gram-negative and anaerobic enteric flora if a biliary tract infection is suspected.
In cases of uncomplicated cholecystitis, outpatient treatment may be appropriate. The following medications may be useful in this context:
- Levofloxacin and metronidazole for prophylactic antibiotic coverage against the most common organisms
- Antiemetics (eg, promethazine or prochlorperazine) to control nausea and prevent fluid and electrolyte disorders
- Analgesics (for example, oxycodone / acetaminophen)
Surgical and intervention procedures used to treat acute cholecystitis
- Laparoscopic cholecystectomy (standard of care for the surgical treatment of cholecystitis)
- Percutaneous drainage
- Endoscopic transmural cholecystistais guided by ultrasound
- Endoscopic drainage of the gallbladder
Finally, we can say that acute cholecystitis is defined as inflammation of the gallbladder, which occurs most commonly due to an obstruction of the cystic duct of cholelithiasis. Ninety percent of cases involve stones in the gallbladder (ie, calculated cholecystitis), and the other 10% of cases represent acalculous cholecystitis. 
The risk factors for cholecystitis reflect those of cholelithiasis and include increasing age, female sex, certain ethnic groups, obesity or rapid weight loss, drugs and pregnancy. Although bile cultures are positive for bacteria in 50-75% of cases, bacterial proliferation may be the result of cholecystitis and not the precipitating factor.