Pancreatic pseudocyst
A pancreatic pseudocyst is an encapsulated, fluid-filled collection lacking solid debris that forms more than 4 weeks after interstitial acute or chronic pancreatitis. Diagnosis rests on contrast-enhanced CT showing a well-defined wall around fluid. Most resolve spontaneously; endoscopic transmural drainage is reserved for symptomatic, infected, or enlarging pseudocysts.
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What this article covers
- Overview
What it is: A pancreatic pseudocyst is pancreatic fluid encapsulated by a well-defined, non-epithelialized wall of granulation and fibrous tissue, arising more than 4 weeks after interstitial acute…
- Epidemiology
Setting: Pseudocysts complicate a minority of acute pancreatitis episodes, arising after interstitial rather than necrotizing disease, and also occur after chronic pancreatitis or pancreatic trauma.
- Risk factors
Interstitial acute pancreatitis: The collection that matures into a pseudocyst arises from duct disruption in edematous pancreatitis, not liquefied necrosis.
- Pathophysiology
Duct disruption: Inflammation or trauma ruptures the main pancreatic duct or a side branch, releasing enzyme-rich secretions into the peripancreatic or retroperitoneal space.
- Clinical features
Time course: Symptoms, when present, emerge weeks after the inciting episode, consistent with the more than 4-week wall-maturation period.
- Differential diagnosis
Acute peripancreatic fluid collection: A sterile, non-encapsulated collection within the first 4 weeks of interstitial pancreatitis, distinguished by the absence of a wall and by usually resolving before the 4-week threshold.
- Diagnosis
What establishes the diagnosis: In a patient whose lipase-confirmed antecedent pancreatitis has been followed for over 4 weeks, contrast-enhanced CT (or MRI) showing a rounded, well-circumscribed…
- Management
First, observe if asymptomatic and uninfected: No drainage regardless of size; manage the antecedent pancreatitis and reassess clinically.
- Complications
Infection: Secondary bacterial infection of the contents produces fever, intensifying pain, and sepsis, and requires antibiotics with drainage.
- Prognosis
Spontaneous resolution: Roughly 50 to 80% of pseudocysts resolve spontaneously within 6 to 12 weeks, making observation the appropriate default for an asymptomatic, uninfected collection.
- Prevention
Manage the underlying pancreatitis promptly: Early, adequately dosed fluid resuscitation and same-admission cholecystectomy for gallstone pancreatitis limit severity and, indirectly, the risk of duct disruption.
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Related articles
- Acute pancreatitis
Acute pancreatitis is acinar-cell autodigestion and inflammation of the pancreas, most often from gallstones or alcohol, diagnosed by the revised Atlanta criteria and graded mild, moderately severe, or severe by organ failure. Management centers on early goal-directed lactated Ringer's resuscitation, analgesia, early enteral feeding, and timed ERCP for gallstone pancreatitis with cholangitis, reserving antibiotics for confirmed infected necrosis.
- Chronic pancreatitis
Chronic pancreatitis is irreversible fibro-inflammatory destruction of the pancreas that produces abdominal pain along with exocrine and endocrine insufficiency, most often from long-term alcohol use in adults and cystic fibrosis in children. Diagnosis rests on CT or MRI showing calcifications and ductal change, and management combines alcohol and tobacco cessation, staged analgesia, pancreatic enzyme replacement, and endoscopic or surgical drainage for ductal obstruction.
- Infected pancreatic necrosis
Infected pancreatic necrosis is secondary bacterial or fungal infection of devitalized pancreatic or peripancreatic tissue, usually one to four weeks into severe acute pancreatitis. Diagnosis rests on gas within a necrotic collection on CT or a positive culture from image-guided aspiration. First-line treatment is a necrosis-penetrant carbapenem such as meropenem plus staged, minimally invasive drainage using the step-up approach.
- Pancreatic cancer
Pancreatic ductal adenocarcinoma usually presents late, with painless obstructive jaundice from a head-of-pancreas mass, weight loss, and sometimes new-onset diabetes or migratory thrombophlebitis. Pancreas-protocol CT defines resectability, endoscopic ultrasound with fine-needle aspiration confirms tissue diagnosis, and only complete surgical resection with pancreaticoduodenectomy offers a chance of cure, which most patients cannot receive.
- Cholelithiasis
Cholelithiasis is the presence of gallstones in the gallbladder, most often cholesterol stones from bile supersaturation, and is asymptomatic in most patients. Symptomatic disease presents as biliary colic, self-limited postprandial right upper quadrant pain without fever, diagnosed by right upper quadrant ultrasound and treated with elective laparoscopic cholecystectomy.
- Acute cholangitis
Acute cholangitis is a bacterial infection of an obstructed biliary tree, classically presenting as Charcot triad of fever, right upper quadrant pain, and jaundice and progressing to septic shock when drainage is delayed. Diagnosis follows the Tokyo Guidelines and severity grade, and treatment combines prompt broad-spectrum antibiotics with biliary drainage, most often by ERCP.