Absence of intrinsic factor

What it means

Absence of gastric intrinsic factor, which is normally produced by the parietal cells of the stomach, and is required for the absorption of vitamin B12.

This feature can be ascertained by immunoassay of gastric juices.

Rare diseases that can present with this1

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Intrinsic factor absent from gastric juice