Question

Which is the microbiological test for diagnosing Leptospira infection?

• A. Cold agglutination
• B. Standard agglutination
• C. Microscopic agglutination test (MAT)
• D. None of these

Hint:

The gold-standard serological test for leptospirosis uses agglutination viewed under the microscope.

Answer 1

The Correct Option is C

Step 1: Leptospira can be demonstrated directly by dark-field microscopy, by immunofluorescence, or by light microscopy after appropriate staining.
Step 2: For serological diagnosis, the microscopic agglutination test (MAT) is the gold-standard test for leptospirosis.
Step 3: A macroscopic agglutination test also exists but MAT is the reference standard, making MAT the correct microbiological test among the options.
Step 4: Cold agglutination is used for Mycoplasma pneumoniae and standard (Widal) agglutination for enteric fever, not Leptospira, so the answer is the Microscopic agglutination test.