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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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A patient presents with a painless ulcer on his penis. A Wasserman test is done and is positive. Wasserman reaction is an example of _
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The correct answer is  Wassermann reaction is an example of a complement fixation test. It is a non specific test for the diagnosis of syphilis. Principle of complement fixation tests: Antigen-antibody complexes fix complement Reference: Ananthanarayan and Paniker&;s Textbook of Microbiology Tenth edition