Lab Dept:


Test Name:


General Information

Lab Order Codes:



Leptospira Agglutination, Serum; Weil’s disease; Leptospirosis Antibody: Leptospira IgM Ab

CPT Codes:

86720 – Antibody; Leptospira

Test Includes:

Leptospira Antibody reported as negative, equivocal or positive.


Test Indications:

As an aid in the diagnosis of leptosprirosis.

Known exposure to contaminated water. Usually abrupt onset with fever; may occur in 2 phases. Phase 1 has fever, chills, headache, muscle aches, vomiting or diarrhea. The patient may recover for a time but will become ill again. If a second phase occurs, it is more severe. The person may have kidney or liver failure or meningitis. This phase is also called Weil’s disease. Incubation range is 2 days–4 weeks.

Lab Testing Sections:

Serology - Sendouts

Referred to:

Mayo Medical Laboratories (MML Test: FLEPM) forward to ARUP.

Phone Numbers:

MIN Lab: 612-813-6280

STP Lab: 651-220-6550

Test Availability:

Daily, 24 hours

Turnaround Time:

1 – 5 days, test performed Monday and Thursday

Special Instructions:



Specimen Type:



SST (Red, gold or marble top tube)

Draw Volume:

3 mL (Minimum: 1.5 mL) blood

Processed Volume:

1 mL (Minimum: 0.5 mL) serum


Routine venipuncture


Special Processing:

Lab Staff: Centrifuge specimen, remove serum aliquot. Store and ship at refrigerated temperatures. Mark specimens as acute or convalescent. Forward promptly.

Patient Preparation:


Sample Rejection:

Mislabeled or unlabeled specimens


Reference Range:

Negative: No significant level of Leptospira IgM detected

Equivocal: Questionable presence of Leptospira IgM detected.
Repeat testing in 10-14 days may be helpful.

Positive: Presence of IgM antibody to Leptospira detected, suggestive of a current or recent infection.

Note: Parallel testing is preferred and convalescent specimen must be received within 30 days from receipt of the acute specimen.

Critical Values:



Serologic results must be correlated with the clinical picture. Sera drawn too close to onset of symptoms may precede the initial IgM antibody response. Acute titers may be delayed or substantially decreased by early and intensive antibiotic treatment.


Qualitative immunoblot


Mayo Medical Laboratories July 2016


3/25/2004: Test moved from the Minnesota Department of Health to Mayo Medical Laboratories.
4/24/2008: Draw volumes temporarily increased for forward to ARUP.
2/17/2011: Testing performed internally at MML. Reference range and volume update.
7/8/16: Test update, MML now forwards to ARUP. Volume, Method and Ref Range updates.