Cholecystitis

Acute inflammation of the gallbladder, typically due to obstruction of the cystic duct.

• Gallstones: Responsible for 90% of cases.
• Acute acalculous cholecystitis: In 10% of cases, no cause of obstruction is found. Notably seen at extremes of age and associated with trauma, burns, and surgery.

• Obstruction causes chemical irritation due to bile stasis.
• Subsequent onset of bacterial infection.

• Traditional referred to as ‘4 F’s‘ (although we don’t love the acronym):
  • Fat (obesity): raised BMI is associated with excess cholesterol in bile due to higher cholesterol levels
  • Female: More common in women (2-3 times), particularly during reproductive years as associated with oestrogen, which increases cholesterol levels in bile.
  • Fertile: increased oestrogen, can lead to gallstones
  • Forty
• Other risk factors
  • Diabetes
  • Drugs: hormone replacement therapy and birth control pills (combined oral contraceptive pill)
  • Conditions like cirrhosis, Crohn’s disease, and certain blood disorders can increase risk
  • Rapid weight loss or low calorie states

• Right upper quadrant pain: Can radiate to the back and shoulder tip.
  • Murphy’s sign: Pain during palpation below the right costal margin on inspiration (only present in 40% of cases)
• Associated with vomiting.
• Systemic symptoms: Such as fever and raised inflammatory markers.

• Ultrasound (investigation of choice): Gold standard, shows gallbladder wall thickening, sludge, distension of gallbladder or bile duct, pericholecystic fluid, and stones if present.

US shows: Distended gall bladder shows oedematous wall, calculi and sludge with pericholecystic collection.

• CT abdomen: If acute undifferentiated abdominal pain.

CT shows: pericholecystic fluid, gallbladder wall thickening and a gallstone in the gallbladder neck (as well as other non-obstructing calculi) – findings that are consistent with acute cholecystitis.

• ERCP
• MRCP
• Blood tests: FBC, LFTs, Amylase, CRP
  • Patients typically have an elevated white blood cell count and CRP
  • Abnormal LFTs may indicate Mirizzi syndrome – a gallstone lodged in the distal cystic duct, leading to external pressure on the common bile duct

• Conservative:
  • IV fluids
  • IV antibiotics (commonly broad-spectrum like co-amoxiclav)
  • Analgesia
• If symptoms persist or complications develop:
  • Urgent intervention, e.g., drainage for gallbladder empyema.
  • Cholecystectomy: Usually performed electively ~6 weeks after symptom resolution, but may be emergency if conservative measures fail.

Early Cholecystectomy:

• Performed within 1 week of symptom onset:
  • Preferred approach to reduce the risk of complications.
  • Typically done laparoscopically.
  • Aims to prevent recurrent attacks and other complications.
• Benefits:
  • Shorter hospital stay.
  • Reduced overall morbidity.
  • Lower risk of bile duct injury when performed by experienced surgeons.

Delayed Cholecystectomy:

• Scheduled 6-12 weeks after initial episode:
  • Considered if the patient’s condition is too severe or if there are contraindications to immediate surgery.
  • Allows time for inflammation to subside, making surgery safer.
• Risks:
  • Potential for recurrent attacks.
  • Possible complications during the waiting period.

A cholecystectomy is generally avoided between 1 week and 6 weeks after the onset of acute cholecystitis due to the following reasons:

• Persistent Inflammation: During this period, the inflammation and oedema from the acute episode may not have fully subsided. This can make the dissection of tissues more difficult and increase the risk of complications such as bile duct injury.
• Increased Risk of Complications: The presence of ongoing inflammation and tissue oedema can lead to higher rates of complications during surgery. These complications include infection, bleeding, and damage to surrounding structures.
• Technical Difficulties: The inflamed and thickened tissues can obscure normal anatomical landmarks, making the surgery more complex and increasing the risk of inadvertent injury.
• Optimal Timing: Evidence suggests that either performing the surgery within the first week or delaying it until after 6 weeks results in better outcomes. Early cholecystectomy can prevent recurrent attacks and complications, while delayed surgery allows the inflammation to completely resolve, making the procedure safer.

• Gallbladder empyema (pus-filled)
• Gallbladder gangrene or perforation
• Biliary peritonitis
• Cholangitis

1. AUGIS: acute gallstone pathway
2. Tokyo Guidelines 2018: diagnostic criteria and severity grading of acute cholecystitis

Radiological images provided by Radiopaedia under a creative commons license:

• Case courtesy of Maulik S Patel, Radiopaedia.org. From the case rID: 20542
• Case courtesy of The Radswiki, Radiopaedia.org. From the case rID: 11161