A 34-year-old woman comes to the emergency department due to a 12-hour history of sudden-onset, upper abdominal pain. She describes the pain as intense, constant, and radiating to the back. The pain is relieved by leaning forward and worsens with eating. The patient also reports nausea and has vomited several times. She has no previous episodes of abdominal pain, fever, chills, weight loss, fatigue, or night sweats. The patient has no known medical conditions and takes no prescription or over-the-counter medications. She does not use alcohol, tobacco, or illicit drugs. Her last menstrual period was 2 weeks ago and was normal. The patient is sexually active with a male partner and uses condoms. Temperature is 36.7 C (98.1 F) , blood pressure is 134/72 mm Hg, pulse is 72/min, and respirations are 14/min. BMI is 24 kg/m². Physical examination shows moist mucous membranes and anicteric sclera. Lung fields are clear, and S1 and S2 are normal. The abdomen is soft and tender in the upper abdomen but without rebound, involuntary guarding, or rigidity. Bowel sounds are normal. Neither hepatomegaly nor splenomegaly is present. Bimanual examination reveals no adnexal masses or tenderness. Neurologic examination is within normal limits.
Which of the following is the most appropriate immediate next step for establishing the diagnosis in this patient?

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Quizplus · Accepted Answer

Explanation: 11ec2b69_c14b_bfd9_8f63_5ffb3ed11f5c_MD0005_00 This patient most likely has acute pancreatitis (AP) presenting with acute, severe epigastric pain radiating to the back and associated with nausea and vomiting. The diagnosis of AP requires 2 of 3 criteria: Acute onset of persistent, severe epigastric pain Elevation of serum lipase or amylase ≥3 times the upper limit of normal (lipase is more specific) Characteristic findings of pancreatitis on abdominal imaging (contrast-enhanced CT scan, MRI) In patients with typical abdominal pain, laboratory analysis (ie, serum lipase) is sufficient to confirm the diagnosis of AP. Establishing the diagnosis with laboratory markers is preferred over imaging due to lower cost, faster result time, and lack of exposure to ionizing radiation. In addition, CT scan has low sensitivity in the first 72 hours of presentation. It is generally reserved for cases of diagnostic uncertainty and would be performed in this patient only if laboratory analysis is unrevealing (eg, normal lipase and/or amylase) (Choices A and B). (Choice D) Endoscopy is generally not helpful in AP. Although endoscopy with retrograde cholangiopancreatography (ERCP) may be used to remove a common bile duct stone in patients with gallstone-induced AP, ERCP is associated with significant risk and should not be used as the initial diagnostic test. (Choice E) An x-ray can help diagnose a perforated peptic ulcer, which typically presents with signs of peritonitis (eg, involuntary guarding, rebound tenderness, rigidity), which are not present in this patient. X-ray is neither sensitive nor specific for AP. Educational objective: The diagnosis of acute pancreatitis can be made when serum lipase (or amylase) levels are ≥3 times the upper limit of normal in the setting of characteristic epigastric abdominal pain. Advanced abdominal imaging (eg, CT scan) should be reserved for cases of diagnostic uncertainty. References: Acute pancreatitis. (http://www.ncbi.nlm.nih.gov/pubmed/25368923) Early phase of acute pancreatitis: assessment and management. (http://www.ncbi.nlm.nih.gov/pubmed/25133018) Clinical guideline: management of gastroparesis. (http://www.ncbi.nlm.nih.gov/pubmed/23147521)

A 34-Year-Old Woman Comes to the Emergency Department Due to a 12-Hour