Can Autoimmune Gastritis Have Negative Antibodies?
At a Glance
Yes, you can have autoimmune gastritis with negative antibody tests. Parietal cell antibodies often disappear in late-stage AIG, and many patients never produce intrinsic factor antibodies. A definitive diagnosis is typically confirmed through an endoscopy with stomach biopsies.
In this answer
3 sections
Yes, you can absolutely have autoimmune gastritis (AIG) even if your blood tests for stomach antibodies are completely normal [1][2]. When your immune system attacks your stomach, doctors typically look for two specific markers in your blood: Parietal Cell Antibodies (APCA) and Intrinsic Factor Antibodies (AIFA) [3][4]. However, neither of these tests is perfect, and testing negative does not rule out the disease [2].
Understanding how these tests perform—their “sensitivity” and “specificity”—explains why this happens.
Parietal Cell Antibodies (APCA): High Sensitivity, but Can Disappear
Parietal cells are the cells in your stomach that produce acid and help you absorb vitamin B12 [3]. APCA tests look for the antibodies attacking these cells. This test is generally considered highly “sensitive,” meaning it catches most cases of AIG, especially in the early stages [3].
However, as autoimmune gastritis progresses into its late stages, the immune system gradually destroys the parietal cells [5][6]. Once these cells are gone, the immune system stops producing the antibodies against them [2]. As a result, APCA levels can drop and eventually disappear entirely [1][2].
Paradoxically, a negative APCA test might not mean you don’t have the disease—it could mean you have advanced, late-stage AIG where the targets of the attack are no longer present [1][2]. While the idea of your stomach cells being “destroyed” sounds frightening, it is important to know that late-stage AIG is highly manageable [7]. Patients live normal, healthy lives by replacing the missing nutrients (such as through vitamin B12 injections or iron supplements) and having regular medical monitoring [8][9].
Intrinsic Factor Antibodies (AIFA): High Specificity, but Low Sensitivity
Intrinsic factor is a protein produced by parietal cells that is strictly required to absorb vitamin B12. The AIFA test checks for antibodies that block this protein.
This test is highly “specific,” meaning if you test positive, you almost certainly have autoimmune gastritis [7]. In particular, it confirms the late stage known as pernicious anemia, a type of anemia caused by severe vitamin B12 deficiency [10]. However, the AIFA test is not very “sensitive” [7]. This means a large percentage of people with AIG simply never produce intrinsic factor antibodies, making a negative result very common even when the disease is active and present [11].
How is it Diagnosed Without Antibodies?
Because standard blood tests don’t always tell the whole story, a definitive diagnosis of AIG does not rely on antibody testing alone. If you have symptoms like unexplained iron deficiency [8], B12 deficiency [7], or gastrointestinal discomfort but test negative for antibodies, your doctor can look at other clues:
- Other Blood Biomarkers: Doctors can check your levels of gastrin and pepsinogen I [12][13]. In AIG, gastrin levels often rise significantly as your body desperately tries to signal your stomach to make more acid [14]. Conversely, your pepsinogen I levels (or the ratio of pepsinogen I to II) will drop [15]. Note that checking these levels typically requires a fasting blood test.
- Endoscopy with Biopsy: The gold standard for diagnosing AIG—regardless of your antibody status—is an upper endoscopy where your doctor takes small tissue samples (biopsies) from specific parts of your stomach (the body and the antrum) [16][14]. AIG typically damages the main body of the stomach but spares the lower section (the antrum). By comparing samples from both areas under a microscope, a pathologist can see the exact pattern of cell damage and inflammation characteristic of autoimmune gastritis [17][18].
Common questions in this guide
Why would my parietal cell antibody (APCA) test be negative if I have autoimmune gastritis?
Can I still have autoimmune gastritis if my intrinsic factor antibodies are negative?
How is autoimmune gastritis diagnosed if my antibody tests are completely normal?
What should I ask my doctor if I have AIG symptoms but my antibody tests are negative?
Questions to Ask Your Doctor
Curated prompts to bring to your next appointment.
- 1.Since my antibody tests were negative but my symptoms continue, should we check my fasting serum gastrin and pepsinogen I levels?
- 2.Given my symptoms and negative antibody tests, is it possible my autoimmune gastritis is in a late 'burned-out' stage?
- 3.If we proceed with an endoscopy, will you be taking separate biopsies from both the antrum and the corpus of my stomach to check for AIG?
- 4.How should we monitor my iron and vitamin B12 levels to ensure I am absorbing nutrients adequately?
Questions For You
Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.
Related questions
References
References (18)
- 1
Decreased anti-parietal cell antibody titer in the advanced phase of autoimmune gastritis.
Nishizawa T, Watanabe H, Yoshida S, et al.
Scandinavian journal of gastroenterology 2022; (57(2)):143-148 doi:10.1080/00365521.2021.1994642.
PMID: 34693845 - 2
Letter to the editor commenting on 'decreased anti-parietal cell antibody titer in the advanced phase of autoimmune gastritis' by Nishizawa et al.
Guo X, Schreurs MWJ, Doukas M, et al.
Scandinavian journal of gastroenterology 2023; (58(7)):838-839 doi:10.1080/00365521.2023.2174816.
PMID: 36734401 - 3
Anti-parietal cell antibodies - diagnostic significance.
Rusak E, Chobot A, Krzywicka A, Wenzlau J
Advances in medical sciences 2016; (61(2)):175-179 doi:10.1016/j.advms.2015.12.004.
PMID: 26918709 - 4
A comparative study of different assays for autoantibodies detection in patients with autoimmune gastritis.
Osmola M, Hémont C, Romańczyk M, et al.
Journal of translational autoimmunity 2025; (10()):100294 doi:10.1016/j.jtauto.2025.100294.
PMID: 40519797 - 5
Parietal Cell Death by Cytokines.
Merchant JL
Cellular and molecular gastroenterology and hepatology 2018; (5(4)):636-637 doi:10.1016/j.jcmgh.2018.01.019.
PMID: 29713663 - 6
Interleukin-17A Promotes Parietal Cell Atrophy by Inducing Apoptosis.
Bockerstett KA, Osaki LH, Petersen CP, et al.
Cellular and molecular gastroenterology and hepatology 2018; (5(4)):678-690.e1 doi:10.1016/j.jcmgh.2017.12.012.
PMID: 29930985 - 7
Antibodies involved in the development of pernicious anemia and other autoimmune diseases.
Morawiec-Szymonik E, Foltyn W, Marek B, et al.
Polish archives of internal medicine 2020; (130(1)):31-37 doi:10.20452/pamw.15094.
PMID: 31813927 - 8
Autoimmune gastritis.
Kulnigg-Dabsch S
Wiener medizinische Wochenschrift (1946) 2016; (166(13-14)):424-430 doi:10.1007/s10354-016-0515-5.
PMID: 27671008 - 9
Graves' disease patients with iron deficiency anemia: serologic evidence of co-existent autoimmune gastritis.
Gianoukakis AG, Gupta S, Tran TN, et al.
American journal of blood research 2021; (11(3)):238-247.
PMID: 34322286 - 10
High frequency of anti-parietal cell antibody (APCA) and intrinsic factor blocking antibody (IFBA) in individuals with severe vitamin B12 deficiency - an observational study in primary care patients.
Salinas M, Flores E, López-Garrigós M, Leiva-Salinas C
Clinical chemistry and laboratory medicine 2020; (58(3)):424-429 doi:10.1515/cclm-2019-0749.
PMID: 31714882 - 11
Insights Into Pediatric Autoimmune Gastritis: Is There a Role for Helicobacter pylori Infection?
Moreira-Silva H, Silva G, Costa E, et al.
Journal of pediatric gastroenterology and nutrition 2019; (68(6)):e99-e104 doi:10.1097/MPG.0000000000002278.
PMID: 30664567 - 12
Update on Serum Biomarkers in Autoimmune Atrophic Gastritis.
Dottori L, Pivetta G, Annibale B, Lahner E
Clinical chemistry 2023; (69(10)):1114-1131 doi:10.1093/clinchem/hvad082.
PMID: 37680186 - 13
Monitoring the follow-up of autoimmune chronic atrophic gastritis using parietal cell antibodies and markers of gastric function.
Panozzo MP, Antico A, Bizzaro N
Journal of translational autoimmunity 2025; (10()):100273 doi:10.1016/j.jtauto.2025.100273.
PMID: 39917315 - 14
Relevance of pepsinogen, gastrin, and endoscopic atrophy in the diagnosis of autoimmune gastritis.
Kishikawa H, Nakamura K, Ojiro K, et al.
Scientific reports 2022; (12(1)):4202 doi:10.1038/s41598-022-07947-1.
PMID: 35273265 - 15
Pathophysiology and laboratory diagnosis of pernicious anemia.
Toh BH
Immunologic research 2017; (65(1)):326-330 doi:10.1007/s12026-016-8841-7.
PMID: 27538411 - 16
Validation of diagnostic strategies of autoimmune atrophic gastritis: A case report.
Sun WJ, Ma Q, Liang RZ, et al.
World journal of clinical cases 2021; (9(31)):9557-9563 doi:10.12998/wjcc.v9.i31.9557.
PMID: 34877290 - 17
Autoimmune Gastritis.
Hall SN, Appelman HD
Archives of pathology & laboratory medicine 2019; (143(11)):1327-1331 doi:10.5858/arpa.2019-0345-RA.
PMID: 31661309 - 18
Multiple Pseudopolyps Presenting as Reddish Nodules Are a Characteristic Endoscopic Finding in Patients with Early-stage Autoimmune Gastritis.
Kotera T, Oe K, Kushima R, Haruma K
Internal medicine (Tokyo, Japan) 2020; (59(23)):2995-3000 doi:10.2169/internalmedicine.4637-20.
PMID: 32759583
This information about autoimmune gastritis testing is for educational purposes only and does not constitute medical advice. Always consult your healthcare provider or gastroenterologist to interpret your specific lab results and symptoms.
Get notified when new evidence is published on autoimmune gastritis.
We monitor PubMed for new peer-reviewed studies on this topic and email a short summary when something meaningful changes.