HELICOBACTER PYLORI ANTIBODY IGM, SERUM

Helicobacter pylori Antibody IgM, Serum

What it is

The Helicobacter pylori (H. pylori) IgM Antibody test is a blood test that detects IgM class antibodies against the H. pylori bacteria. H. pylori is a common stomach bacterium associated with gastritis, peptic ulcer disease, and gastric cancer. IgM antibodies are typically the earliest immune response, indicating a recent or acute infection compared to IgG (past or chronic) and IgA (active mucosal infection).

Uses

This test is used to:

• Detect recent or acute H. pylori infection.
• Differentiate between early-stage infection and past exposure (IgG) or chronic activity (IgA).
• Support evaluation of patients with unexplained gastrointestinal symptoms.
• Complement stool antigen or urea breath tests for more accurate diagnosis.

Symptoms That May Lead to the Test

Doctors may recommend this test if you have symptoms such as persistent upper abdominal pain, bloating, nausea, loss of appetite, indigestion, unexplained weight loss, or signs of gastrointestinal bleeding (vomiting blood or black, tarry stools).

Abnormal Results

Positive IgM: Indicates recent or acute H. pylori infection. Additional tests (IgG, IgA, stool antigen, or urea breath test) may be required to confirm and stage the infection.

Negative IgM: Suggests no evidence of recent infection. However, IgM may be absent in long-standing infections, so IgG and IgA testing may still be useful in symptomatic patients.

Risks

The test requires a routine blood sample. Risks are minimal and limited to mild pain, bruising, or dizziness at the puncture site, which usually resolve quickly.