Cause of Aortic Regurgitation

How common is cardiovascular syphilis as a cause of aortic regurgitation?

If a person is not aware of an infection that happened perhaps over 20 years ago, could this be a cause of ortic valve disease due to a problem with the aorta near the heart?  Would these problems show up on an echocardiogram to give the cardiologist an indication that something could be wrong with the aorta causing the valve problem?  Would a blood test (RPT)show if a person was infected ten to twenty years ago?  (This test was done 15 years ago and was negative)  Do cardiologists routinely test for this as a diagnostic procedure when the cause of the valve problem can't be determined?

I read that tertiary syphilis could cause regurgitation and wanted your opinion.

Thank you.

[CCF CARDIO MD - DLB]

Syphilis is listed as a cause of ortic regurgitation in every medical textbook. However, in reality, it rarely occurs, especially in the United States and especially over the past several decades. Cardiologists hardly ever test for it. There are blood tests to detect syphilis infection but even if they are positive, it is not necessarily the case that syphilis caused the aortic problem. At the time of valve surgery, if the tissue is examined by a skilled pathologist, the diagnosis of syphilitic aortitis can be made.