Leaking Blood Vessels May Cause Sepsis

The common belief is that sepsis, a potentially deadly illness where the bloodstream is overwhelmed by bacteria, is caused by a bacterial infection. A new study indicates that might not be the case.

Researchers at St. Michael’s Hospital have suggested a new theory about what causes sepsis, which is often fatal when infection spreads throughout the body.

Ask your doctor about sepsis risk following a serious illness or injury.

Dr. Warren Lee, the lead researcher and a physician at St. Michael's Hospital, said that the actual cause of sepsis might instead be leaking blood vessels, instead of the symptom it was previously believed to be.

Worldwide about 1,400 people die from sepsis each day. In Canada it is the second leading cause of death in hospital intensive care units. Despite an overwhelming amount of research the death rate remains high at between 30 and 50 percent.

Treatment usually includes surgical removal or drainage of the infected site, antibiotics and supportive care.

Dr. Lee said numerous potential drugs for sepsis had failed in clinical trials after success in animals or through in vitro. He said that the repeated failure of clinical trials suggests that some fundamental knowledge is lacking in the current understanding of the pathogenesis of human sepsis.

Dr. Lee said one reason previous trials may have failed is that they haven’t taken into account a key feature of sepsis in humans -- diffuse microvascular leakage, which is widespread leakage from small blood vessels, which leads to swelling in tissues and organs. This causes organs throughout the body to malfunction. There have not yet been clinical trials of drugs designed to prevent or treat leaky blood vessels.

He also added that a change in thinking about the devastating illness could lead to novel treatments, such as those designed to stop leaking blood vessels, that can save lives.

The research was published in the journal Science Translational Medicine.