Examkin

Question

Difficulty: MediumInterpreting Imaging Results

A 52-year-old man is evaluated in the hospital for worsening abdominal pain and a new-onset fever. He was admitted three weeks ago for severe acute pancreatitis secondary to alcohol use disorder and has been managed with supportive care. Over the past 24 hours, his temperature has increased to 38.9°C (102.0°F). His blood pressure is 110/70 mmHg, pulse is 112/min, and respirations are 18/min. Physical examination shows marked epigastric tenderness with guarding. Laboratory studies show a leukocyte count of 18,500/mm³. A contrast-enhanced CT scan of the abdomen reveals an 8-cm well-circumscribed collection of fluid and necrotic tissue in the lesser sac. Multiple small pockets of gas are visible within this collection. Intravenous meropenem is initiated. Based on the interpretation of these imaging findings, which of the following is the most appropriate next step in management?

  1. Image-guided percutaneous catheter drainageAnswer
  2. B
    Diagnostic CT-guided fine-needle aspiration
  3. C
    Immediate open surgical necrosectomy
  4. D
    Endoscopic retrograde cholangiopancreatography
  5. E
    Continued supportive care with serial CT imaging

Answer

Image-guided percutaneous catheter drainage
The correct response is image-guided percutaneous catheter drainage. The patient's clinical presentation of fever and leukocytosis three weeks after an episode of severe acute pancreatitis is highly suspicious for infected pancreatic necrosis. The most critical aspect of his evaluation is the interpretation of the contrast-enhanced CT scan, which demonstrates gas bubbles within a necrotic collection. The presence of gas on a CT scan is a highly specific, pathognomonic finding for infected necrosis caused by gas-forming organisms. Because the diagnosis is confirmed by imaging, the immediate next step in management (after initiating broad-spectrum antibiotics) is source control. The current standard of care dictates a 'step-up' approach, which begins with minimally invasive techniques such as image-guided percutaneous catheter drainage or endoscopic transluminal drainage. This approach significantly reduces major complications and mortality compared to primary open surgery.

Step-by-Step Solution

1
Interpret the clinical deterioration in the context of the recent history.
The patient has worsening fever, pain, and leukocytosis three weeks after an episode of severe acute pancreatitis, strongly suggesting a local infectious complication.
Pancreatic necrosis typically becomes infected 2 to 4 weeks after the initial presentation.
2
Analyze the specific findings on the contrast-enhanced CT scan.
The CT scan shows a necrotic fluid collection containing multiple small pockets of gas.
Imaging is the primary modality to differentiate between sterile and infected complications.
3
Synthesize the imaging findings to establish a definitive diagnosis and select the appropriate intervention.
Gas within the collection confirms infected pancreatic necrosis. The appropriate management is the 'step-up' approach, beginning with percutaneous catheter drainage.
Minimally invasive drainage reduces systemic inflammation and avoids the high morbidity associated with immediate open surgical necrosectomy.

Key Concept

The presence of gas within a pancreatic fluid collection on CT imaging is pathognomonic for infected pancreatic necrosis, which mandates treatment with broad-spectrum antibiotics and minimally invasive drainage (the step-up approach).
Rate this question

Topics

Interpreting Imaging Results

More questions from this topic