Loyola Study Provides Insight Into Combined Radiation Injury from Possible Nuclear Disaster

Now the first study of its kind in 50 years is providing new insights into this phenomenon, called combined radiation injury (CRI).

Researchers at Loyola University Chicago Stritch School of Medicine have shown how CRI causes the intestines to leak bacteria into surrounding tissue. The study also showed that radiation and burns have a synergistic effect that make them far more deadly when they act in combination.

The study is published in the October 2013 issue of the journal Shock.

Findings could lead to new treatments for victims, as well as pretreatments for first responders, said senior author Elizabeth Kovacs, PhD. First author is Stewart Carter, MD.

“The use of nuclear technology and the potential for its implementation in warfare and terrorism highlight the importance of this study,” researchers concluded. “Insight into the effects of combined radiation injury on the gut will help direct management of survivors of nuclear disaster.”

Normally, cells that line the lumen of the intestine prevent bacteria and bacterial products from leaking out. The cells are held together by “tight junctions.” Radiation can damage and kill these cells, and a burn injury can trigger an inflammatory response that breaks down tight junctions. This effectively opens up the protective lining, allowing bacterial products to leak out of the intestine. Such leaks can cause death by sepsis.

In the study, researchers found that combined radiation and thermal injury triggered 100 times greater leakage of bacteria across the intestinal lining than the leakage seen in control groups exposed to radiation alone, burn alone, or no injury at all.

“To our knowledge, we are the first to present gastrointestinal findings of this nature in any CRI model, with the exception of early studies on CRI in the 1960s,” the researchers wrote.

Kovacs added: “We hope we never will have to respond to a nuclear disaster. But if such a disaster were to occur, our findings could be part of our preparedness.”

Kovacs is director of research and Carter is a research resident in the Burn and Shock Trauma Research Institute of Loyola University Chicago Stritch School of Medicine. Other co-authors, all at Loyola, are Anita Zahs, PhD; Jessica Palmer, MS; Lu Wang, MD; Luis Ramirez; and Richard L. Gamelli, MD, FACS. Gamelli is director of the Burn and Shock Trauma Research Institute.

The study is titled “Intestinal Barrier Disruption as a Cause of Mortality in Combined Radiation and Burn Injury.” It is funded by the National Institutes of Health and the Dr. Ralph and Marian C. Falk Medical Research Trust.

The Loyola University Chicago Health Sciences Division (HSD) advances interprofessional, multidisciplinary, and transformative education and research while promoting service to others through stewardship of scientific knowledge and preparation of tomorrow's leaders. The HSD is located on the Health Sciences Campus in Maywood, Illinois. It includes the Marcella Niehoff School of Nursing, the Stritch School of Medicine, the biomedical research programs of the Graduate School, and several other institutes and centers encouraging new research and interprofessional education opportunities across all of Loyola University Chicago. The faculty and staff of the HSD bring a wealth of knowledge, experience, and a strong commitment to seeing that Loyola's health sciences continue to excel and exceed the standard for academic and research excellence. For more on the HSD, visit LUC.edu/hsd.