Define Acute Cholecystitis. Describe its clinical features and complications.

The Concept

Acute cholecystitis is acute inflammation of the gallbladder, and in over 90% of cases it is calculous — caused by a stone impacting in the cystic duct or Hartmann's pouch. The persistent obstruction causes the gallbladder to distend, its wall to become inflamed and oedematous, and secondary bacterial infection to supervene. This is the key difference from biliary colic, where the obstruction is only transient and there is no inflammation.

Clinical Features

There is constant right-upper-quadrant or epigastric pain (unlike the colicky, self-limiting pain of biliary colic), often radiating to the right shoulder, with fever, nausea and vomiting. The classic sign is Murphy's sign — the patient catches their breath (arrest of inspiration) as the examiner's hand presses the inflamed gallbladder against it during deep inspiration in the RUQ. Blood tests show a neutrophil leucocytosis and raised CRP.

Investigation & Management

Ultrasound confirms the diagnosis, showing gallstones, a thick-walled gallbladder and pericholecystic fluid, often with a sonographic Murphy's sign. Management is analgesia, intravenous fluids and antibiotics, followed by laparoscopic cholecystectomy — ideally early ('hot' gallbladder, within about 72 hours), or as an interval procedure. Complications of untreated disease include empyema, gangrene and perforation of the gallbladder.

Acalculous Cholecystitis

A minority (~5–10%) have acalculous cholecystitis — inflammation without stones — occurring typically in critically ill, fasting or post-operative patients from gallbladder stasis and ischaemia. It is easily missed and carries a higher risk of gangrene, so a high index of suspicion is needed in the sick patient.

Early VS Delayed Surgery

There is a clear rationale for early ('hot') laparoscopic cholecystectomy within about 72 hours of onset: operating during the acute window (before dense adhesions form) is safe and avoids the risk of recurrent attacks while waiting. Beyond that window, if presentation is late, some surgeons prefer to cool the inflammation and perform an interval cholecystectomy some weeks later. Either way, definitive removal of the gallbladder is the goal, since attacks recur.

The Bottom Line

Acute cholecystitis is thus a stone-obstructed, inflamed (± infected) gallbladder — constant pain, fever, positive Murphy's sign — confirmed on ultrasound and treated with antibiotics and laparoscopic cholecystectomy, with acalculous disease a trap in the critically ill.

Complications to Anticipate

The complications of untreated acute cholecystitis form a progression the clinician must anticipate: a mucocele or empyema (a pus-filled gallbladder), then gangrene from pressure necrosis, and finally perforation — either localised (a pericholecystic abscess) or free (biliary peritonitis). Elderly and diabetic patients are especially prone to gangrene. Recognising a patient who is failing to settle, becoming more toxic, or developing a spreading peritonitis mandates urgent intervention rather than continued conservative treatment.

Murphy sign — arrest of inspiration on right subcostal palpation.

• Acute cholecystitis = gallbladder inflammation, usually from a stone impacted in the cystic duct (calculous).
• Constant RUQ pain (not colicky), fever, vomiting, positive Murphy's sign, leucocytosis.
• Ultrasound: stones, thick wall, pericholecystic fluid.
• Treat with analgesia, IV fluids, antibiotics + laparoscopic cholecystectomy (early, ~within 72 h); complications: empyema, gangrene, perforation.
• Acalculous cholecystitis occurs in the critically ill/post-operative patient (stasis/ischaemia).