Blasting Bacteria

One of the gravest threats to anyone severely burned or injured -- or to soldiers wounded in battle -- is massive, system-wide bacterial infection. Such infection with toxic, "gram-negative" bacteria kills up to 100,000 Americans a year, many of them surgical patients and trauma victims. Last week researchers at the University of California at San Diego reported a major victory in the war against these microbes. Using injections of a biotech product called monoclonal antibodies in patients suffering from toxic infections and septic shock, they reduced the expected death rate 40%, in some cases rescuing patients from the brink of death. The advance comes just in time for soldiers who might be wounded in the gulf war.

Gram-negative bacteria -- so named because they do not retain a laboratory stain devised by the Danish bacteriologist Christian Gram -- are usually harmless. They reside on the skin and in the gut, where they aid in digestion. But any significant disruption to the body's immune response -- caused, for instance, by severe burns, chemotherapy or major abdominal surgery -- allows these rod-shaped bacteria to multiply out of control and invade other parts of the body, eventually entering the bloodstream. Once there, one part of the bacterial cell wall called endotoxin can trigger a cascade of lethal effects, culminating in multiple organ failure and death, sometimes within hours.

The new treatment, reported by Dr. Elizabeth Ziegler and colleagues in the New England Journal of Medicine, employs a man-made antibody called HA-1A designed to zero in on the endotoxin molecule and render it harmless. Although the Food and Drug Administration has yet to approve HA-1A for use in the U.S., the agency has given the Pentagon special permission to utilize the antibody in the gulf. Large quantities are on hand in MASH units and field hospitals.

The antibody does not provide a guaranteed cure. In the study, 30% of the patients receiving the treatment died (vs. 50% of those who did not receive it). Still, HA-1A appears to be one more high-tech weapon U.S. soldiers can count on.