Examkin

Soru

Zorluk: ZorGastroenterology and Hepatology

A patient in his mid-forties is evaluated in the gastroenterology outpatient clinic due to chronic, high-volume watery diarrhea and persistent burning epigastric pain. His symptoms have been refractory to high-dose omeprazole therapy over the past six months. An upper gastrointestinal endoscopy performed recently revealed thickened gastric folds, multiple ulcerations in the descending duodenum, and an additional solitary ulcer in the proximal jejunum. Rapid urease testing and histology for Helicobacter pylori were negative. The physician strongly suspects a neuroendocrine etiology. Arrange the following diagnostic and therapeutic steps in the most appropriate chronological order for evaluating and managing this patient's suspected condition.

  1. 1Discontinue proton pump inhibitor therapy and measure fasting serum gastrin concentration.
  2. 2Measure gastric pH to differentiate from achlorhydria.
  3. 3Administer intravenous secretin and measure subsequent serum gastrin levels.
  4. 4Perform a somatostatin receptor positron emission tomography (PET/CT) scan.
  5. 5Refer the patient for surgical exploration and tumor resection.

Cevap

The correct chronological sequence begins with stopping the proton pump inhibitor to obtain an accurate fasting serum gastrin, followed by measuring gastric pH to rule out achlorhydria. Next, a secretin stimulation test biochemically confirms the gastrinoma. Imaging with a somatostatin receptor PET/CT is then performed to localize the tumor, ultimately guiding definitive surgical resection.
The correct sequence follows the standard diagnostic algorithm for Zollinger-Ellison syndrome. Biochemical screening must occur first, requiring the cessation of acid-suppressing medications to prevent false positives. Because intermediate gastrin levels can be seen in other conditions, gastric pH and a secretin stimulation test are required for definitive biochemical confirmation. Only after biochemical proof is established should functional imaging be performed to localize the tumor. Surgical resection is the final step, dependent on precise anatomical localization.

Adım Adım Çözüm

1
Discontinue the proton pump inhibitor and measure the fasting serum gastrin.
Obtains an accurate baseline gastrin level.
Acid suppression causes physiologic hypergastrinemia, which confounds the initial screening test for Zollinger-Ellison syndrome.
2
Measure gastric pH.
Confirms an acidic gastric environment (pH < 2).
Differentiates gastrinoma from secondary hypergastrinemia caused by achlorhydria, such as in pernicious anemia.
3
Perform a secretin stimulation test.
Shows a paradoxical rise in serum gastrin.
Definitively confirms the biochemical diagnosis of Zollinger-Ellison syndrome when fasting gastrin levels are non-diagnostic.
4
Perform a somatostatin receptor PET/CT scan.
Localizes the neuroendocrine tumor.
Identifies the primary tumor location (typically in the gastrinoma triangle) and rules out metastatic disease prior to surgical intervention.
5
Refer for surgical exploration and tumor resection.
Definitive management of the localized tumor.
Surgery is the treatment of choice for localized, non-metastatic gastrinomas to prevent malignant progression and cure the hypersecretory state.

Anahtar Kavram

Diagnostic and management algorithm for Zollinger-Ellison syndrome (Gastrinoma)
Bu soruyu puanla

Konular

Gastroenterology and Hepatology

Bu konudan daha fazla soru