What is gallbladder hydrops, how is it diagnosed, and what is the recommended treatment for a healthy adult compared to a high‑risk patient?

Gallbladder Hydrops: Definition, Diagnosis, and Treatment

Definition and Pathophysiology

Gallbladder hydrops (also called gallbladder mucocele) is an uncommon condition characterized by marked gallbladder distention filled with clear, mucous-like inspissated bile rather than normal bile. 1, 2

• The condition results from cystic duct or gallbladder neck obstruction (typically by a stone), leading to reabsorption of bile pigments and salts, leaving behind sterile, viscous, nearly colorless fluid ("white bile"). 2
• The gallbladder pressure averages 61.5 cm saline (range 15-115 cm), and the fluid is roughly isotonic with blood (295 mosmol/kg). 2
• Bilirubin, bile salts, cholesterol, phospholipids, and protein are reduced to non-measurable amounts or concentrations below 1 mg%. 2
• In 78% of cases, the contents are clear "white bile" that is always very viscous and typically sterile. 2

Diagnostic Approach

Ultrasound is the investigation of choice, demonstrating a markedly distended gallbladder without calculi (in acalculous cases) or with an obstructing stone, normal biliary ducts, and absence of congenital malformation. 3, 4

Key Diagnostic Features:

• Gallbladder distention (can exceed 200 mm in maximal length in severe cases) 1
• Normal intrahepatic and extrahepatic bile ducts 3, 4
• Absence of pericholecystic fluid or wall thickening in uncomplicated cases 5
• Negative Murphy's sign in many cases, particularly in pediatric or atypical presentations 3, 4

Clinical Presentation:

• Most patients are asymptomatic and diagnosed incidentally on imaging. 1
• Symptomatic patients may present with abdominal pain, vomiting, palpable abdominal mass, and/or tenderness. 4
• Atypical presentations can mimic acute appendicitis, intussusception, or other surgical emergencies. 4

Treatment Algorithm

For Healthy Adults with Asymptomatic Gallbladder Hydrops:

Expectant management is strongly recommended for asymptomatic gallbladder hydrops without signs of acute inflammation, as the risks of surgical intervention outweigh the benefits. 5

Management Steps:

1. Confirm absence of acute cholecystitis criteria: no wall thickening, no pericholecystic fluid, negative Murphy's sign, and no fever or systemic signs of infection. 5, 6
2. Observe with serial imaging if the patient remains asymptomatic. 5
3. Re-evaluate immediately if the patient develops:
   • Right upper quadrant pain or tenderness 5
   • Fever or signs of systemic infection 5
   • Positive Murphy's sign on examination 5
   • New laboratory abnormalities suggesting inflammation or cholangitis 5

Important Caveats:

• Do not confuse asymptomatic hydrops with acalculous cholecystitis, which occurs primarily in critically ill patients and presents with wall thickening, pericholecystic fluid, and clinical signs of infection. 5
• Prophylactic cholecystectomy should be considered only in specific high-risk subgroups: calcified ("porcelain") gallbladder, gallstones >3 cm, or specific ethnic populations with high gallbladder cancer rates. 5

For High-Risk Patients (Elderly, Multiple Comorbidities, ASA III/IV):

High-risk patients with symptomatic gallbladder hydrops require careful risk-benefit assessment, with percutaneous cholecystostomy serving as a bridge to definitive surgery or as definitive treatment in those truly unfit for surgery. 7, 6

Management Algorithm for High-Risk Patients:

Step 1: Initial Assessment

• Obtain liver function tests (AST, ALT, alkaline phosphatase, GGT, bilirubin, albumin) to assess for biliary obstruction. 6
• Measure inflammatory markers (WBC, CRP, procalcitonin) to evaluate severity. 6
• Consider CT imaging if clinical suspicion remains high for complicated cholecystitis (93% specificity). 6

Step 2: Medical Management

• Do not start empirical antibiotics unless there are clear signs of infection (fever, elevated WBC, elevated procalcitonin, or clinical deterioration). 6
• If antibiotics are indicated, use piperacillin-tazobactam or a carbapenem (imipenem, meropenem, ertapenem) for 4-7 days. 6

Step 3: Intervention Decision

• For patients with acute symptoms who are truly unfit for surgery: Percutaneous cholecystostomy is an option, though it is significantly inferior to cholecystectomy with major complication rates of 53% vs 5%. 7
• For patients who stabilize after cholecystostomy: Consider interval cholecystectomy once the patient becomes a moderate-risk surgical candidate. 7
• For patients with peritonitis, sepsis, or gangrenous cholecystitis: Immediate surgical intervention is required, as delayed surgery increases mortality from 12-16%. 6

Step 4: Surgical Approach if Pursued

• Laparoscopic cholecystectomy is preferred even in elderly patients, with lower 2-year mortality compared to nonoperative management. 7
• Age alone is NOT a contraindication to cholecystectomy. 7
• For Child-Pugh A and B cirrhosis, laparoscopic cholecystectomy is first choice; Child-Pugh C patients should avoid cholecystectomy unless clearly indicated. 7

Special Considerations in Pediatric Populations:

In children with gallbladder hydrops (often associated with Kawasaki disease), medical management is preferred, and surgical intervention is reserved only for complications. 3

• Simple cholecystostomy is safe and sufficient if surgery is required. 3
• Ultrasonography is helpful for correct diagnosis and can exclude biliary tree dilatation and cholelithiasis. 3
• Ultrasound-guided percutaneous transhepatic gallbladder aspiration (UG-PTGA) can relieve gallbladder tension and acute complaints without complications. 8

Common Pitfalls to Avoid:

• Do not perform cholecystectomy for vague dyspeptic symptoms (bloating, belching, fatty food intolerance), as these are not reliably attributable to gallstones and often persist after surgery. 5
• Do not delay definitive surgery beyond 7-10 days once the decision for surgery is made in symptomatic cases, as this increases complications and conversion rates. 7
• Do not assume observation is "safe" in symptomatic disease, as it carries a 6.63-fold increased risk of gallstone-related complications and 60% of patients will eventually require surgery under worse conditions. 7
• Do not overlook gangrenous cholecystitis, which may present without Murphy's sign and requires urgent surgery. 6