Parietal cell antibody

The expected result is Negative; a positive result is common in the general population, particularly in older people, and is read together with the intrinsic factor antibody and B12 level.

Parietal cells are the cells in the stomach lining that make acid and intrinsic factor. In autoimmune gastritis, the condition that leads to pernicious anaemia, the immune system makes antibodies against these cells. The test looks for those antibodies in the blood. It is more often positive than the intrinsic factor antibody but is also found in many people without pernicious anaemia, which makes it a less decisive test.

Doctors request it alongside the intrinsic factor antibody when vitamin B12 is low, to look for autoimmune gastritis as the cause. It is also sometimes requested in people with autoimmune thyroid disease, type 1 diabetes or unexplained low iron, since autoimmune gastritis reduces the stomach acid needed to absorb iron.

• Autoimmune gastritis and pernicious anaemia
• Autoimmune thyroid disease, type 1 diabetes, vitiligo and other autoimmune conditions
• Older age, where it is found in a fair proportion of the general population without any illness
• Helicobacter pylori infection of the stomach, in some people

• A negative result means the antibody was not found; it does not exclude pernicious anaemia

• It is positive in a sizeable minority of healthy older people in the general population
• It is found with other autoimmune conditions without any stomach problem
• Different laboratory methods differ in how readily they call a result positive

No fasting needed. Read together with the intrinsic factor antibody, vitamin B12 and a full blood count.

Written by a UK consultant physician. Typical UK adult reference ranges; your laboratory's own printed range takes precedence.