Friday, September 27, 2013

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

MAYWOOD, Ill. – A nuclear bomb or nuclear reactor accident can produce a deadly combination of radiation exposure and injuries such as burns and trauma.

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 material 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 & 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 & 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.

About Loyola University Health System

Loyola University Health System (LUHS) is a member of Trinity Health. Based in the western suburbs of Chicago, LUHS is a quaternary care system that includes Loyola University Medical Center (LUMC), located on a 61-acre campus in Maywood, Gottlieb Memorial Hospital (GMH), on a 36-acre campus in Melrose Park, and convenient locations offering primary and specialty care services throughout Cook, Will and DuPage counties. At the heart of LUMC is a 547-licensed-bed hospital that houses the Center for Heart & Vascular Medicine, the Cardinal Bernardin Cancer Center, a Level 1 trauma center, a burn center, a children's hospital, Loyola Outpatient Center, and Loyola Oral Health Center. The campus also is home to Loyola University Chicago Stritch School of Medicine, Loyola University Chicago Marcella Niehoff School of Nursing and the Loyola Center for Fitness. The GMH campus includes a 254-licensed-bed community hospital, a Professional Office Building with 150 private practice clinics, an adult day care program, the Gottlieb Center for Fitness, the Loyola Center for Metabolic Surgery and Bariatric Care and the Loyola Cancer Care & Research at the Marjorie G. Weinberg Cancer Center at Melrose Park.

Trinity Health is one of the largest multi-institutional Catholic health care delivery systems in the nation. It serves people and communities in 22 states from coast to coast with 93 hospitals, and 120 continuing care locations — including home care, hospice, PACE and senior living facilities — that provide nearly 2.5 million visits annually.