Bring back bloodletting?

Imagine giving captopril, a blood pressure-lowering agent, to patients infected with anthrax, many of whom may have extremely low blood pressures because they're in shock or on the verge of it. Sounds crazy, right? But that's just what some clinicians suggested in the wake of the 2001 anthrax letters, based on animal studies showing that captopril could inhibit the lethal anthrax toxin.For a more recent example of how enthusiasm for important findings in basic science can often get the best of c

Sep 27, 2004
Ivan Oransky
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Imagine giving captopril, a blood pressure-lowering agent, to patients infected with anthrax, many of whom may have extremely low blood pressures because they're in shock or on the verge of it. Sounds crazy, right? But that's just what some clinicians suggested in the wake of the 2001 anthrax letters, based on animal studies showing that captopril could inhibit the lethal anthrax toxin.

For a more recent example of how enthusiasm for important findings in basic science can often get the best of caution when it comes to their clinical relevance – with potentially dangerous results – see the following bit from a Perspective in the Sept. 10, 2004, issue of Science. The article, by Tracey Rouault of the National Institutes of Health's Cell Biology and Metabolism Branch, accompanied a study on how Staphylococcus aureus gets the iron it needs to be an effective infectious agent.

''The protective effects of hypoferremia may explain the mystery of why physicians embraced bloodletting as a therapeutic procedure for more than 2,500 years,'' Rouault writes. "As recently as 1942, Sir William Osler's highly regarded medical textbook advocated bloodletting as a treatment for acute pneumonia: 'To bleed at the onset in robust healthy individuals in whom the disease sets in with great intensity and harsh fever is good practice.' The development and widespread use of antibiotics in the mid-20th century obviated the need to employ questionable treatments such as bloodletting. However, the discovery that S. aureus depends on heme iron for growth in its animal hosts suggests that bloodletting in the pre-antibiotic era may have been an effective mechanism for starving bacterial pathogens of iron and slowing bacterial growth.''

Not to mention an effective mechanism of starving sick patients of iron and making them anemic, which doesn't seem like a terribly good idea and is probably why bloodletting killed thousands. French statisticians knew by the mid-18th century that bloodletting hurt more than it helped. Rouault may have been giving too much credit to her physician predecessors. In an E-mail to The Scientist, she acknowledged that ''the cure might be worse for the disease'' and that she doesn't ''think there is any reason to return to bloodletting.'' Agreed. If you have the misfortune of becoming infected with methicillin-resistant S. aureus, keep the bloodletters at bay.

- Ivan Oransky