Mouse Study Suggests Cipro, Other Fluoroquinolone Antibiotics Pose Danger for Patients at Risk for Aortic Aneurysm

Published on November 28, 2017 by Sandy Liebhard

A newly published study suggests that Cipro and other fluoroquinolone antibiotics may not be the best choice for patients at risk for aortic aneurysm.

Study Designed to Determine Cause-Effect Relationship Between Fluoroquinolones and ADD

Some retrospective clinical studies have pointed to a link between fluoroquinolone antibiotics, such as Cipro, Levaquin, and Avelox, and an increased risk of aortic aneurysms and dissections (AAD), a disease that carries a high risk of death from aortic rupture. However, those findings do not constitute proof that such an association exists.

To determine whether  or not thee is a cause-effect association, a team of researchers at Baylor College of Medicine, the Texas Heart Institute and Baylor College of Medicine’s Cardiovascular Research Institute worked with a mouse model of human ADD. All animals included in the study had normal or moderately stressed aortas, and all were treated with ciprofloxacin (the active ingredient in Cipro) or a placebo.

Their animals’ aortas were examined four weeks after treatment was initiated. Those with normal, unstressed aortas did not show any significant effect, regardless of whether they received a placebo or the drug.

Among the mice with moderately stressed aortas that were administered ciprofloxacin:

• 79% developed ADD
• 67% had aortic dissection
• 15% had a fatal rupture

By comparison, only 45% of the mice with moderately stress aortas that were administered a placebo developed ADD. None had a rupture, and only 24% developed an aortic dissection.

“Our study suggests that in this model of moderately stressed mouse aortas, ciprofloxacin exposure results in the disease progressing more rapidly and more severely, which is exactly the concern,” senior author Dr. Ying H. Shen, said in a press release announcing the findings.

“If we consider the clinical data and our experimental results that prove causation in a reliable model of AAD, I believe we have enough evidence for changing guidelines on the use of fluoroquinolone antibiotics for people who have an aneurysm or are at risk for getting an aneurysm,” first author Dr. Scott A. LeMaire said. “I am hopeful that these guidelines can be changed in short order.”

Fluoroquinolone Side Effects

Cipro and other fluoroquinolone antibiotics are indicated to treat a wide range of bacterial infections. However, in recent years the drugs have been the subject of multiple health warnings for peripheral neuropathy, tendon damage, and other persistent, debilitating side effects. Most recently, the U.S. Food & Drug Administration (FDA) modified the boxed warning included on all fluoroquinolone labels to state that their risks outweigh any potential benefits for patients with certain uncomplicated infections when other treatment options are available.

Research published in the November 2015 issue of  JAMA: Internal Medicine suggested that patients treated with fluoroquinolones were nearly twice as likely to suffer an aortic aneurysm or aortic dissection within 60 days of exposure compared with non-use. The authors of the study also pointed out that drugs like Cipro are associated with several collagen-related disorders. Collagen is also a major extracellular matrix component of the aortic wall.

Several aortic aneurysm lawsuits have been filed against the manufacturers of Levaquin. Hundreds of additional lawsuits have also been filed on behalf of patients who allegedly developed peripheral neuropathy allegedly due to their use of Levaquin, Cipro and Avelox.