Nokea
A patient had been provisionally diagnosed with syphilis. A laboratory assistant took the blood serum for an immunologic test based on the detection of antibodies preventing the movement of treponemas and causing their death. What reaction was used for the diagnosis?
Correct Answer: A
Rationale: The correct answer is A: Immobilization. This technique is called the Treponema pallidum immobilization (TPI) test, used to diagnose syphilis. The rationale is as follows:
1. TPI test detects antibodies that prevent the movement of treponemas, causing their death.
2. By immobilizing the treponemas, it indicates the presence of specific antibodies against syphilis.
3. This test is highly specific for syphilis diagnosis as it directly targets the causative agent.
Other choices are incorrect:
B: Complement binding - Not specific to syphilis, more commonly used for other diseases.
C: Agglutination - Detects clumping of particles, not specific to treponemas or syphilis.
D: Precipitation - Involves the formation of a solid, not directly related to treponema movement or death.