Leptospira Antibody, IgM by Dot Blot

Samples interpreted as negative indicate that antibody is not present in the sample, or is below the detection level of the method.  Since antibodies may not be present during early disease, confirmation two to three weeks later is recommended.  An initially-negative result followed by a positive result indicates IgM seroconversion.

Equivocal specimens should be cautiously interpreted.  Further testing with an additional specimen is recommended. If the specimen remains equivocal, a second serological method should be considered if leptospirosis infection is still suspected.

Samples interpreted as positive may indicate the specific antibody.  Antibody presence alone cannot be used for diagnosis of acute infection, however, because antibodies from prior exposure may circulate for a prolonged period of time.