What does serology testing for H. pylori detect?

What does serology testing for H. pylori detect?

• A. Anti-H. pylori antibodies using ELISA
• B. H. pylori antigen in stool
• C. H. pylori DNA in blood
• D. Urea levels in breath

Answer: (A)

Serology testing for H. pylori measures the host’s immune response to the bacteria by detecting antibodies against H. pylori in the blood, usually using an ELISA. The antibodies (often IgG) indicate exposure to the organism, not necessarily an active infection, because they can remain elevated after the infection has been treated or resolved. This is why serology is useful for assessing prior exposure in certain contexts, but it isn’t ideal for confirming an active infection or for confirming eradication. Other tests target the bacterium directly or its activity: stool antigen tests look for H. pylori protein in stool, the urea breath test detects urease activity by measuring labeled CO2 in exhaled breath, and molecular methods look for H. pylori DNA in tissue or stool.

Serology testing for H. pylori measures the host’s immune response to the bacteria by detecting antibodies against H. pylori in the blood, usually using an ELISA. The antibodies (often IgG) indicate exposure to the organism, not necessarily an active infection, because they can remain elevated after the infection has been treated or resolved. This is why serology is useful for assessing prior exposure in certain contexts, but it isn’t ideal for confirming an active infection or for confirming eradication. Other tests target the bacterium directly or its activity: stool antigen tests look for H. pylori protein in stool, the urea breath test detects urease activity by measuring labeled CO2 in exhaled breath, and molecular methods look for H. pylori DNA in tissue or stool.