Description
Overview: While IgM antibodies appear early in an infection and fade relatively quickly, IgG antibodies appear later (usually 2-3 weeks after infection starts) and can persist in the body for years. This test is essential for distinguishing between a new, acute infection and one that has been present for months or years.
Clinical Significance:
-
Chronic Infection: High IgG levels in the absence of IgM usually indicate chronic Brucellosis. This form of the disease can cause long-term fatigue, joint destruction, and recurring fevers.
-
Past Exposure: Low but detectable levels of IgG may simply mean the person was exposed to Brucella in the past and has recovered.
-
Treatment Monitoring: For patients on antibiotics for Brucellosis, doctors monitor IgG levels over months. A gradual decline in IgG suggests the treatment is working effectively.
-
Relapse: A sudden rise in IgG levels in a previously treated patient is a strong indicator of a relapse (return of the infection).
When is this test recommended?
-
For patients with symptoms lasting months or years (chronic fatigue, arthritis, lower back pain).
-
To differentiate between acute (IgM) and chronic (IgG) stages of the disease.
-
To monitor occupational health in high-risk workers (vets, farmers) to check for historical exposure.
Sample Requirements:
-
Specimen: Serum (Blood).
-
Container: Gold Top (SST) or Red Top Tube.
-
Preparation: No special preparation or fasting is required.
