No U.S. president died from leeches. While leeches were commonly used in medical practices throughout history, including during the time periods when many U.S. presidents lived, there is no record of any president dying from their use.
The practice of using leeches for medical purposes, known as hirudotherapy, was popular in the 18th and 19th centuries. Leeches were believed to draw out "bad blood" and cure various ailments. However, this practice fell out of favor as medical science advanced and better treatments were discovered.
While leeches are no longer a mainstream medical treatment, they are still used in some modern medical practices, particularly in microsurgery and plastic surgery.
