Review Question - QID 210550

A 42-year-old man presents to his primary care provider for abdominal pain. He reports that for several months he has been experiencing a stabbing pain above the umbilicus during meals. He denies associated symptoms of nausea, vomiting, or diarrhea. The patient’s past medical history is significant for hypertension and hyperlipidemia for which he takes amlodipine and atorvastatin. His family history is significant for lung cancer in his father. The patient is a current smoker with a 20-pack-year smoking history and drinks 3-5 beers per week. His temperature is 98.5°F (36.9°C), blood pressure is 127/78 mmHg, pulse is 90/min, respirations are 16/min, and oxygen saturation is 99% on room air. Initial laboratory testing is as follows:

Serum:
Na+: 141 mEq/L
K+: 4.6 mEq/L
Cl-: 102 mEq/L
HCO3-: 25 mEq/L
Urea nitrogen: 14 mg/dL
Creatinine: 1.1 mg/dL
Glucose: 120 mg/dL
Calcium: 8.4 mg/dL
Alkaline phosphatase: 66 U/L
Aspartate aminotransferase (AST): 40 U/L
Alanine aminotransferase (ALT): 52 U/L
Gastrin: 96 pg/mL (<100 pg/mL)
Lipase: 90 U/L (<160 U/L)

The patient is started on a proton pump inhibitor without symptomatic improvement after 6 weeks. He is referred for an upper endoscopy, which demonstrates erosive gastritis, 3 ulcers in the duodenum, and 1 ulcer in the jejunum. A biopsy of the gastric mucosa is negative for H. pylori. Which of the following is the most appropriate next step in management?