Infectious Disease· Topic 7.7 Hepatobiliary infections· 7.7.9

Acalculous cholecystitis

Acalculous cholecystitis is acute gallbladder inflammation without gallstones, driven by ischemia and biliary stasis in critically ill, fasting, or TPN-dependent patients. Ultrasound showing gallbladder wall thickening or pericholecystic fluid without stones supports the diagnosis. Untreated mortality reaches 75 percent, so treatment starts with intravenous antibiotics plus percutaneous cholecystostomy, followed by cholecystectomy once the patient stabilizes.

12 min read6 practice questions8 key factsSubscriber article
  • Topic review
    The full article, organized the way the exam asks it.
  • ABIM-format MCQs
    Vignettes with an explanation for every wrong answer.
  • Key facts
    The numbers and thresholds worth memorizing, up front.
  • AI tutor
    MedBrain answers the question you're stuck on.

What this article covers

  • Overview

    Acalculous cholecystitis is acute gallbladder inflammation without gallstones or cystic duct obstruction.

  • Epidemiology

    Acalculous cholecystitis occurs almost exclusively in patients who are already critically ill: those in an intensive care unit (ICU) after major trauma, extensive burns, cardiac surgery, or a cardiac…

  • Risk factors

    Critical illness and prolonged fasting: any condition that keeps a patient nil by mouth removes the cholecystokinin-driven gallbladder contraction that normally prevents bile stasis.

  • Pathophysiology

    Two processes combine to cause acalculous cholecystitis: bile stasis and gallbladder wall ischemia.

  • Clinical features

    Alert patients: present much like calculous cholecystitis, with right upper quadrant (RUQ) or epigastric pain, nausea, RUQ tenderness, and often a positive Murphy sign.

  • Differential diagnosis

    Calculous acute cholecystitis: the near-identical sibling, but ultrasound shows gallstones or sludge obstructing the cystic duct, whereas acalculous disease shows wall thickening or pericholecystic fluid without any stone.

  • Diagnosis

    The diagnosis is established by combining the high-risk clinical setting, a critically ill, fasting, sedated, or TPN-dependent patient, with sonographic findings of gallbladder wall thickening…

  • Management

    First, resuscitate and obtain blood cultures, then start empiric intravenous antibiotics with gram-negative and anaerobic coverage: piperacillin-tazobactam 3.375 g IV every 6 hours.

  • Complications

    Gallbladder gangrene and perforation: the wall injury from ischemia progresses to necrosis and full-thickness perforation faster than in calculous disease, since there is no antecedent stone to slow the process.

  • Prognosis

    Untreated disease carries a mortality of up to 75%, which is why early recognition and prompt source control take priority over any single diagnostic test.

  • Prevention

    Favor early enteral nutrition over TPN when the gastrointestinal tract is functional, starting within 24 to 48 hours of ICU admission when feasible, since enteral feeding preserves the…

Read the whole article

Subscribing to Internal Medicine opens every article, the full question bank and MedBrain, on the web, iPhone and Android.