Acute Cholecystitis Clinical Overview
I. The "On-Call" Snapshot
Clinical Significance in Malaysia: This is one of the most common causes of acute abdominal pain presenting to our Emergency Departments, often related to our diet and high prevalence of metabolic syndrome.
High-Yield Definition: Acute cholecystitis is the acute inflammation of the gallbladder, most commonly ( >90% of cases) caused by cystic duct obstruction from a gallstone.
Clinical One-Liner: Basically, the gallbladder is swollen and angry because a stone is blocking its exit.
II. Etiology & Risk Factors
Etiology:
Calculous Cholecystitis (90-95%): Mechanical obstruction of the cystic duct by a gallstone.
Acalculous Cholecystitis (5-10%): Gallbladder inflammation without stones. Seen in critically ill patients (e.g., ICU, on TPN, major trauma/burns) due to bile stasis and gallbladder ischemia. Carries a much higher mortality.
Risk Factors: Remember the classic "5 Fs":
Fat (Obesity)
Female
Forty (Age > 40)
Fertile (Multiparous)
Fair (More common in Caucasians, but still very prevalent in our population)
Other key risks in Malaysia: Diabetes Mellitus, dyslipidemia, rapid weight loss.
III. Quick Pathophysiology
It's a simple mechanical problem that turns into an inflammatory one.
Obstruction: A gallstone gets impacted in the cystic duct.
Stasis & Distension: Bile can't get out. The gallbladder distends, increasing intraluminal pressure.
Inflammation: The distension and concentrated bile salts irritate and inflame the gallbladder wall. This is initially a chemical inflammation.
Ischemia & Infection: Persistent pressure compromises blood flow to the gallbladder wall, leading to ischemia and necrosis. Stagnant bile allows for secondary bacterial infection (commonly E. coli, Klebsiella).
IV. Clinical Assessment
Red Flags & Immediate Actions:
Hypotension (SBP < 90 mmHg) or shock: -> Alert senior/surgical registrar immediately, get 2 large bore IV lines, start fluid resuscitation, take blood cultures, and start IV antibiotics. This could be sepsis or perforation.
Peritonism (guarding, rebound tenderness): -> Suspect gallbladder perforation and biliary peritonitis. Alert your senior. Keep NBM.
Altered Mental Status: -> Could be sepsis-induced encephalopathy. Check a bedside glucose and alert your senior.
History:
Common (>50%):
Right Upper Quadrant (RUQ) pain: Steady, severe, and lasts > 6 hours.
Radiation of pain to the right shoulder or back (Boas' sign).
Nausea and vomiting.
Fever with or without chills.
Often a preceding history of fatty food intake triggering biliary colic.
Pertinent Negatives: Ask about jaundice or tea-coloured urine. Their presence suggests a stone has migrated to the common bile duct (choledocholithiasis) causing obstruction, which is now cholangitis, a more urgent problem.
Physical Examination:
Vitals: Check for fever and tachycardia.
Abdomen:
Look for any distension.
Palpate gently, starting away from the RUQ. Localised tenderness is key.
Murphy's Sign: This is the hallmark sign. Press firmly on the RUQ at the costal margin and ask the patient to take a deep breath in. A positive sign is a sharp increase in pain causing an inspiratory arrest.
Clinical Pearl: Don't just ask "Is it painful?" when you press. Any inflamed area is painful. A true Murphy's sign is when the patient stops breathing in because the inflamed gallbladder hits your hand.
V. Diagnostic Workflow
Differential Diagnosis:
Acute Pancreatitis:
Points For: Epigastric pain radiating to the back, vomiting. Can be caused by gallstones (biliary pancreatitis).
Points Against: Pain is usually more central.
How to Differentiate: Serum amylase or lipase (lipase is more specific).
Perforated Peptic Ulcer:
Points For: Sudden onset severe upper abdominal pain.
Points Against: History of PUD/H.pylori/NSAID use. Pain is often more epigastric.
How to Differentiate: Erect CXR looking for air under the diaphragm.
Acute Cholangitis:
Points For: RUQ pain, fever.
Points Against: Presence of jaundice is the key differentiator.
How to Differentiate: Charcot's triad (RUQ pain, fever, jaundice). Significantly deranged LFTs (cholestatic picture).
Inferior Myocardial Infarction:
Points For: Can present as epigastric pain.
Points Against: Absence of fever, no localised tenderness.
How to Differentiate: Do an ECG on every patient with upper abdominal pain. Check troponins if suspicious.
Investigations Plan:
Bedside / Initial (First 15 Mins):
ECG: Mandatory to rule out a cardiac cause.
Urine FEME: Can help rule out a renal cause like pyelonephritis.
First-Line Labs & Imaging:
Full Blood Count (FBC): Expect leukocytosis (high white cells) with a neutrophil predominance.
Renal Profile (RP): Important baseline before starting IV contrast or NSAIDs.
Liver Function Test (LFT): May show a mild elevation in ALP and bilirubin due to surrounding inflammation, but a significant rise should make you think of choledocholithiasis or Mirizzi syndrome.
C-Reactive Protein (CRP): Will be elevated; a good marker for inflammation.
Ultrasound Abdomen: This is the investigation of choice. You are looking for:
Presence of gallstones.
Gallbladder wall thickening (>3 mm).
Pericholecystic fluid (fluid around the gallbladder).
Sonographic Murphy's sign (pain on pressing with the probe).
Confirmatory / For Complications:
CT scan: Not needed for routine diagnosis. It's useful if you suspect complications like perforation, empyema, or gangrene, or if the ultrasound is equivocal.
VI. Staging & Severity Assessment
We use the Tokyo Guidelines 2018 (TG18) to classify severity. This is important as it dictates management.
Grade I (Mild):
Patient meets diagnostic criteria for acute cholecystitis.
No signs of organ dysfunction.
Healthy patient with only mild inflammation of the gallbladder.
Impact on management: Can undergo early laparoscopic cholecystectomy safely.
Grade II (Moderate):
Associated with any one of the following:
Elevated WBC > 18,000/μL.
Palpable tender mass in the RUQ.
Duration of symptoms > 72 hours.
Marked local inflammation on imaging (e.g., pericholecystic abscess, gangrenous cholecystitis).
Impact on management: Still a candidate for early cholecystectomy, but may be a more difficult operation. Requires urgent intervention.
Grade III (Severe):
Associated with dysfunction of at least one organ system:
Cardiovascular: Hypotension requiring vasopressors.
Neurological: Decreased level of consciousness.
Respiratory: PaO2/FiO2 ratio <300.
Renal: Oliguria, Creatinine > 2.0 mg/dL (177 μmol/L).
Hepatic: PT-INR > 1.5.
Hematological: Platelet count < 100,000/μL.
Impact on management: These patients are too sick for immediate surgery. They need urgent supportive care in HDU/ICU and gallbladder drainage (usually percutaneous cholecystostomy) as a bridge to surgery later.
VII. Management Plan
Immediate Stabilisation (The ED/On-Call Plan):
NBM: Keep patient Nil By Mouth.
IV Access & Fluids: Secure IV access and start hydration (e.g., Normal Saline 0.9%).
Analgesia: This is painful. Give IV Tramadol or a parenteral opioid like Pethidine or Morphine.
IV Antibiotics: Start empirical antibiotics to cover common gram-negative and anaerobic organisms. As per the Malaysian National Antimicrobial Guideline, a good start is:
IV Amoxicillin/Clavulanate 1.2g Q8H or
IV Ceftriaxone 2g OD (+/- IV Metronidazole 500mg Q8H if you suspect biliary-enteric anastomosis or severe disease).
Definitive Treatment (The Ward Round Plan):
First-Line: Early Laparoscopic Cholecystectomy.
This is the gold standard treatment.
"Early" means within the same hospital admission, ideally within 72 hours to 7 days of symptom onset. This reduces total hospital stay and morbidity compared to the old "cool down and come back in 6 weeks" approach.
For High-Risk / Unfit for Surgery (Grade III):
Percutaneous Cholecystostomy: An interventional radiologist places a drain into the gallbladder under imaging guidance to decompress it. This controls the sepsis. The patient can then have an interval cholecystectomy weeks later when they are more stable.
Long-Term & Discharge Plan:
Post-operatively, monitor for complications (bile leak, surgical site infection).
Discharge with a follow-up appointment in the Surgical Outpatient Department (SOPD) in about 2 weeks for wound review and histology results.
VIII. Complications
If diagnosis or treatment is delayed:
Immediate (first 24-48 hours):
Gangrenous Cholecystitis: Ischemia leads to necrosis of the gallbladder wall. Management: Emergency cholecystectomy.
Perforation: Can lead to a localised abscess or generalised biliary peritonitis. Management: Emergency surgery (laparotomy is more likely).
Short-Term (days):
Empyema of Gallbladder: The gallbladder fills with pus. Management: Urgent drainage and cholecystectomy.
Mirizzi Syndrome: A large stone in the cystic duct compresses the common hepatic duct, causing jaundice. Management: Complex surgical procedure.
IX. Prognosis
Excellent for Grade I and II disease treated with early cholecystectomy. Mortality is <1%.
Prognosis worsens significantly with Grade III disease (mortality can be >10%), increasing age, and presence of comorbidities. Acalculous cholecystitis also has a much higher mortality rate.
Top 3 Prognostic Factors: Age, severity grade (TG18), and time to intervention.
X. How to Present to Your Senior
Use the SBAR format. Be concise.
"Dr., for review please. This is Puan Lim from Bed 10, a 52-year-old lady with T2DM, who presented with 24 hours of constant RUQ pain and fever.
On examination, she is febrile at 38.5°C, tachycardic at 110, but her BP is stable. She has a positive Murphy's sign.
Her bloods show a white count of 16 and a CRP of 150. Ultrasound confirms acute cholecystitis with a thickened wall and pericholecystic fluid.
My diagnosis is Acute Cholecystitis, likely Tokyo Grade II. I have kept her NBM, started IV fluids, analgesia, and IV Augmentin. I would like to refer her to the on-call surgical team for consideration of early cholecystectomy."
XI. Summary & Further Reading
Top 3 Takeaways:
Suspect acute cholecystitis in any patient with sustained (>6 hours) RUQ pain, fever, and localised tenderness.
Diagnosis is clinical, confirmed with an ultrasound of the abdomen.
Management is supportive care (NBM, fluids, antibiotics) followed by early laparoscopic cholecystectomy, with severity assessed by the Tokyo Guidelines 2018.
Key Resources:
Tokyo Guidelines 2018 (TG18) for Acute Cholecystitis: PubMed Link to TG18 Flowchart and Criteria
UpToDate: Search for "Acute calculous cholecystitis: Clinical features and diagnosis" and "Treatment of acute calculous cholecystitis".
Malaysian National Antimicrobial Guideline (2019): For local antibiotic recommendations.
