Gastric parietal cell antibodies (GPCA)
| Category | Immunology |
|---|---|
| Test background |
These antibodies are directed against the acid producing enzyme H+/K+ ATPase (gastric proton pump) found within the canaliculi of the gastric parietal cells and gastric microsomes. Antibodies to gastric parietal cells (GPCA) are commonly associated with iron deficiency anaemia and are a risk factor for the development of autoimmune atrophic gastritis. They are seen in around 5-10% of the healthy population and in 20% of patients with H.pylori infection. Those positive for parietal cell antibodies should have iron and vitamin B12 levels checked and be screened for Intrinsic factor antibodies and H.pylori infection. GPCA is tested by indirect immunofluorescence on mouse liver/kidney/stomach (LKS) sections. They are often detected incidentally in patients being screened for autoimmune liver disease. |
| Clinical Indications |
Atrophic gastritis. Present in the early stages of pernicious anaemia, frequently diminishing with disease progression. |
| Reference range | Negative |
| Sample & container required | Serum (RST rust top) |
| Sample volume | 5-10 mL blood (1 mL serum) |
| Turnaround time | 7 days |
| Notes | Currently unaccredited due to change in platform. |