Bloody Good

Anti-tTG IgA (Celiac) Blood Test

Type

Blood Testing

Duration

15 min

Results

4 days

Evaluates immune system function through white blood cell and antibody measurements.

Celiac disease blood testing screens for antibodies that indicate an autoimmune reaction to gluten — a protein found in wheat, barley, and rye. The primary marker is tissue transglutaminase IgA (tTG-IgA), which is positive in roughly 98% of people with active celiac disease. Total IgA is also measured because some people have IgA deficiency, which can cause false-negative celiac results. Celiac disease affects approximately 1% of the population globally but is significantly underdiagnosed, with most cases going undetected for years. Left untreated, celiac disease can lead to nutrient malabsorption, osteoporosis, infertility, and increased risk of certain cancers.

Key Details

Biomarkers
2–4 celiac markers
Fasting Required
No
Key Requirement
Must be eating gluten for accurate results
Sample Type
Blood draw
Turnaround
3–5 business days

Who Is This For?

Anyone experiencing chronic digestive symptoms like bloating, diarrhea, or abdominal pain. People with unexplained iron deficiency anemia, fatigue, or bone loss. Those with a family history of celiac disease (10% risk in first-degree relatives). Anyone considering going gluten-free who wants a diagnosis first — important because testing is only accurate while eating gluten.

What's Included

Tissue transglutaminase IgA (tTG-IgA)
Total IgA level
Endomysial antibodies (EMA) — if comprehensive panel

Preparation Required

You must be eating gluten regularly for at least 6 weeks before testing — eliminating gluten before the test can cause a false negative. No fasting required. Continue your normal diet including bread, pasta, and other gluten-containing foods.

Frequently Asked Questions