Leptospira Antibody, IgM

This test measures the levels of IgM antibodies specific to Leptospira bacteria in your blood. The test helps detect and confirm leptospirosis, a zoonotic infection caused by Leptospira which affects animal as well as human hosts. Natural reservoirs for these infections are wild rodents and certain domesticated animals. The infection occurs via direct or indirect human contact with water, food, or soil contaminated with animal urine containing the Leptospira antigens. Symptoms of leptospirosis include high fever, headache, muscle pain, nausea, or jaundice. Leptospira IgM antibody testing is done for diagnosing leptospirosis, assessing the severity of the infection, monitoring the effectiveness of treatment, and identifying recent exposure to Leptospira bacteria. Your doctor may recommend this test if you have symptoms of leptospirosis, have been exposed to potentially contaminated water or animals if you live or work in areas with a high prevalence of leptospirosis, and if you have a suspected or confirmed diagnosis of leptospirosis. A positive result signifies the detection of leptospira IgM antibodies may indicate a recent infection or recent exposure to antigens (vaccine). The equivocal result indicates that the test needs to be repeated. If the results of a fresh sample are still equivocal then it is considered negative or should be tested by an alternative/ confirmatory method.

A negative result signifies that Leptospira IgM antibodies are not detected. Since antibodies may not be present or may be present at undetectable levels during early disease, repeat testing of a convalescent sample collected in 2 to 3 weeks is recommended. Negative results do not exclude infection.