E16.4

HCC Category Mapping

What This Code Means

The stomach or pancreas is producing excessive amounts of gastrin, a hormone that increases stomach acid.

Coding Tips

• •This code is often associated with Zollinger-Ellison syndrome; document if this diagnosis is present
• •Verify whether gastrin elevation is primary or secondary to another condition

Clinical Significance

E16.4 identifies increased secretion of gastrin, most commonly caused by a gastrinoma (Zollinger-Ellison syndrome). This condition causes excessive gastric acid production leading to severe peptic ulcer disease, often refractory to standard therapy, diarrhea, and potential gastrointestinal bleeding. Gastrinomas may be sporadic or part of multiple endocrine neoplasia type 1.

Documentation Requirements

• ✓Documentation must include elevated serum gastrin levels, clinical manifestations (refractory peptic ulcers, diarrhea), and the suspected or confirmed underlying cause.
• ✓Imaging studies localizing the gastrinoma and any association with multiple endocrine neoplasia should be documented.

Commonly Confused Codes