Can Acalculous Cholecystitis Cause Septic Shock?
Yes, acalculous cholecystitis (ACC) absolutely can cause septic shock and is recognized as a life-threatening source of biliary sepsis in critically ill patients, with biliary origin being an independent risk factor for mortality in septic shock. 1
Evidence for ACC as a Cause of Septic Shock
The 2020 World Society of Emergency Surgery guidelines explicitly identify ACC as a cause of septic shock, stating that in patients with septic shock, biliary origin of peritonitis (including ACC) was a significant risk factor for mortality at multivariate analysis (OR 3.5; 95% CI 1.09–11.70, p = 0.03). 1 Furthermore, patients with septic shock from biliary sources had a mortality rate of 35% compared to 8% in those without septic shock. 1
Pathophysiology and Clinical Context
ACC develops through spontaneous gangrene of the gallbladder which, without prompt diagnosis and treatment, progresses to perforation. 1 The condition is caused by infection, with Clostridium perfringens implicated as a causative organism, though Escherichia coli and Klebsiella pneumoniae are the most frequently isolated pathogens. 1, 2
The disease occurs predominantly in critically ill patients with multiple risk factors including: 3, 4
- Sepsis from other sources
- Previous surgery or trauma
- Burns
- Total parenteral nutrition
- Prolonged fasting
- Mechanical ventilation
- Opiate sedation
- Multiple transfusions
- Hypotension
Mortality and Severity
ACC carries substantial mortality risk, particularly when complicated by septic shock: 4
- Hospital mortality in operatively treated ACC patients reaches 44% 4
- Mortality is directly related to the degree of organ failure, with non-survivors having significantly higher SOFA scores (12.9 vs. 9.5, p = 0.007) 4
- 64% of ACC patients have three or more failing organs at the time of cholecystectomy 4
- Gangrenous ACC occurs in 52.4% of postoperative cases with a mortality rate of 21.1% 5
Critical Management Implications
When ACC causes septic shock, immediate broad-spectrum antibiotics must be administered within the first hour of recognition, as this significantly impacts mortality outcomes. 6 Piperacillin/Tazobactam is the preferred empiric antibiotic (6g/0.75g loading dose followed by 4g/0.5g every 6 hours or 16g/2g by continuous infusion). 6
Source control through cholecystectomy is definitive treatment and must be achieved as soon as hemodynamically feasible, as inadequate source control is associated with significantly elevated mortality rates. 6 The 2020 CHOCOLATE trial demonstrated that early laparoscopic cholecystectomy is superior to percutaneous drainage even in high-risk patients (APACHE score 7-14), with only 5% complications versus 53% in the drainage group. 1
Diagnostic Challenges
A critical pitfall is that localizing right upper quadrant pain and tenderness is often absent in sedated or ventilated patients with ACC, requiring a high index of suspicion. 1 The only differentiating features in a septic patient may be elevation in alkaline phosphatase or glutamyl transferase. 1
Ultrasound findings (gallbladder distension, wall thickening, free fluid) are not diagnostic, as these changes are frequently demonstrable in critically ill patients who do not develop ACC. 1 Serial ultrasound examinations have excellent negative predictive value when abnormalities fail to progress. 1
Key Clinical Pearls
- ACC should be suspected in any critically ill patient with unexplained sepsis or septic shock, particularly those with multiple risk factors 7, 3
- Early diagnosis and intervention are crucial, as ACC is associated with high mortality but outcomes improve dramatically with prompt treatment 7, 4
- Antibiotic pharmacokinetics are significantly altered in septic shock; daily reassessment and dose adjustment based on pathophysiological status is mandatory 1, 6
- Bile cultures are positive in only 29-54% of ACC cases, making empirical broad-spectrum coverage essential 2