Which diagnostic test for suspected peptic ulcer disease in children may yield false negative results?

Which diagnostic test for suspected peptic ulcer disease in children may yield false negative results?

• A. Esophagogastroduodenoscopy
• B. Esophagogastroduodenoscopy is not listed as an option for this question
• C. Upper GI series
• D. Lactose hydrogen breath test

Answer: (C)

The key idea here is that some diagnostic tests for peptic ulcers in children are less sensitive than others and can miss real disease, leading to a false negative result. An upper GI series uses barium to visualize the lining of the stomach and duodenum, but small or flat ulcers—especially in the duodenal bulb or gastric antrum—can be difficult to see on radiographs. Mucosal changes may be subtle or transient, so the study can appear normal even when an ulcer is present. This limited sensitivity is why it may yield a false negative. In contrast, esophagogastroduodenoscopy directly visualizes the mucosa and can reveal ulcers that radiographs miss; it also allows biopsy to check for Helicobacter pylori, making it the more definitive test. The lactose hydrogen breath test, meanwhile, is used to diagnose lactose intolerance, not peptic ulcer disease, so it isn’t appropriate for detecting ulcers. So, the upper GI series is the test most likely to miss an existing ulcer and yield a false negative.

The key idea here is that some diagnostic tests for peptic ulcers in children are less sensitive than others and can miss real disease, leading to a false negative result.

An upper GI series uses barium to visualize the lining of the stomach and duodenum, but small or flat ulcers—especially in the duodenal bulb or gastric antrum—can be difficult to see on radiographs. Mucosal changes may be subtle or transient, so the study can appear normal even when an ulcer is present. This limited sensitivity is why it may yield a false negative.

In contrast, esophagogastroduodenoscopy directly visualizes the mucosa and can reveal ulcers that radiographs miss; it also allows biopsy to check for Helicobacter pylori, making it the more definitive test. The lactose hydrogen breath test, meanwhile, is used to diagnose lactose intolerance, not peptic ulcer disease, so it isn’t appropriate for detecting ulcers.

So, the upper GI series is the test most likely to miss an existing ulcer and yield a false negative.