Insurgents in the Bloodstream

[admin]

Insurgents in the Bloodstream
Proceedings | Capt. Chas Henry (Ret.) | February 21, 2008
"It's why I lost my leg, so it sucks."

The assessment, from a 22-year-old Marine toughing out physical
therapy on two prosthetic limbs, is laconic, matter-of-fact. Sgt. David
Emery lost one leg in February 2007 when a suicide bomber assaulted the
checkpoint near Haditha, Iraq, where he and fellow Marines stood guard.
Military surgeons were forced to remove his remaining leg when it
became infected with acinetobacter baumannii-a strain of highly
resistant bacteria that since U.S. forces began fighting in Iraq and
Afghanistan has threatened the lives, limbs, and organs of hundreds
wounded in combat.

"They could have saved it," says Emery. "They had a rod in it, but
then the bacteria was in too bad and my white blood cell count was up
to 89,000-and they told my mom on a Friday that they had to take it."

Emery's mother recalls that the hazard was not confined to her son's
limbs.

"He ended up getting it in his stomach," says Connie Emery, "and they
tried to close his stomach back up, but when they did, the stitches
ended up pulling away because the infection was taking over."

An Army infectious disease physician says the germ has spread rapidly
since the wars in Afghanistan and Iraq began. "Prior to the war, we
were seeing one to two cases of acinetobacter infection per year,"
remembers Lt. Col. Kimberly Moran, deputy director for tropical public
health at the Uniformed Services University of the Health Sciences in
Bethesda, Maryland.

"Now that's much different. We've had hundreds of positive cultures
over the last four years."

And the toll has been serious, observes Army Col. Glenn Wortmann,
acting chief of infectious disease at Walter Reed Army Medical Center
in Washington, D.C. "Of the infectious disease problems that have come
out of the conflict," notes Dr. Wortmann, "it is the most important
complication we've seen."

Find out more about veteran health benefits.

Most striking about the problem is that men and women wounded in
combat have acquired the bacteria in the very hospitals where
aggressive surgery has, in many cases, saved their lives. "The
outbreak," acknowledges a Defense Department fact sheet, "appears to
have started during the care of patients (both U.S. military and non-U.
S.) in the combat support hospitals of Iraq and Afghanistan. "

"They go to what's called 'far forward' surgical outfits where the
main concern is keeping them alive," explains Dr. Rox Anderson of
Harvard Medical School, "and in the process there's not a hundred
percent of the [anti-contamination ] controls. Despite a great effort by
the military medical people, there's a high risk of infection anyway."

Once established at frontline surgical sites, the bacteria began
"traveling with patients or on patients," says Dr. Moran, "from Iraq
all the way back to Walter Reed, with stops along the way through the
evacuation chain and getting into our hospitals." There, she adds, "it
was spread from patient to patient through various means, just being on
surfaces and having one person come in a room after another person has
left."

Most evidence of the bacteria has been confirmed at military hospitals
in Germany, the Washington, D.C., area, and Texas -- though cases have
also been confirmed on board the hospital ship USNS Comfort and at
Tripler Army Medical Center in Hawaii.

(As Proceedings went to press, the Baltimore Sun reported an outbreak
of acinetobacter baumannii infections at the University of Maryland
Medical Center.)

The persistence of the outbreak has pushed it to momentous
proportions. "I believe this is the largest in-hospital acinetobacter
outbreak in history," asserts Dr. Timothy Endy, a retired Army colonel
now teaching infectious disease medicine at the State University of New
York, Upstate Medical University. Endy battled the bacteria while
attending to patients at Walter Reed.

Researchers say they don't know exactly how acinetobacter baumannii
first made its way into frontline treatment facilities. Early
suspicions pointed to the possibility that the germs, mixed with soil,
were blown deep into penetrating wounds. Some physicians speculated
that bacteria residing in the combat zone had settled onto the skin of
service members-lying dormant until open wounds allowed the bugs to
create havoc. Small-sample testing, however, has indicated little or no
evidence of problem-causing acinetobacter in Iraqi soil. And the only
Iraq or Afghanistan veterans so far showing signs of acinetobacter
colonization on their skin are those who have spent time in casualty
treatment centers.

Moreover, say scientists, nothing in the character of the outbreak
would indicate that it originated as a result of intentional biological
attack.

The bug's dangerous effects were first noticed just weeks into the
March 2003 assault on Iraq. During April of that year, then-Lt. Cdr.
Kyle Petersen, a Navy physician treating battle casualties on board the
Comfort, observed a number of not-easily-explaine d patient deaths. He
contacted fellow infectious disease specialists via online message
boards, describing his American and Iraqi patients' symptoms-and, when
they were eventually available, their lab results. The interaction
helped rapidly identify the problem and initiated testing of frontline
medical facilities.

"There were bacteria," recalls Moran, "acinetobacter bacteria, on
hospital surfaces like in operating rooms, on ventilator machines, or
on light surfaces or environmental control units."

At first glance, acinetobacter baumannii does not seem particularly
fiendish. It is neither intensely virulent nor remarkably energetic.
Its name, in fact, derives from the Greek word akinetos, meaning
"unable to move." But, as hundreds of those wounded in combat have
learned, it exhibits one particularly troubling genius. Noteworthy even
among better-known, more-feared microorganisms, it is able to steal
resistance capabilities from other bacteria with which it comes into
contact.

In addition to agonizing over what treatment to use, physicians worry
about when they should bring medications to bear. This is particularly
difficult since tests to prove infection take days. So a doctor may
have to wait up to 72 hours to learn if bacteria have colonized on a
patient's skin or, more dangerously, insinuated themselves into a
wound.

"Is my patient infected, or just colonized?" asks Petersen, recalling
the dilemma faced when suspecting that acinetobacter is threatening a
patient. "If [the person's skin] is colonized and I over-treat him, I
could damage his kidneys. If he's infected, and I ignore that and say
he's colonized, he could die."

"The infection, if it goes on," notes Anderson, "sometimes will lead
to amputation, so these are tough choices."

Defense Department records-provided in response to a December 2007
query from Proceedings- indicate that from March 2003 to March 2005
acinetobacter infections attacked more than 250 patients at U.S.
military healthcare facilities. As of June 2006, the same documents
say, seven deaths had been linked to acinetobacter- related
complications. The records did not contain figures for the bacteria's
impact during the remainder of 2006 and 2007.

While the majority of those fighting acinetobacter infection in
military hospitals have been deployed to Iraq or Afghanistan, up to a
third have not -- infants and the elderly among those apparently
acquiring the bacteria in armed forces healthcare centers.

Those hit hardest are typically the weakest of the weak. In the case
of men and women hurt on the battlefield, observes Anderson, those with
"complex wounds, combination of burns, blast injury, and lacerations. "

Of the seven people the Defense Department acknowledges to have died
because of acinetobacter- related complications, five were non-active
duty patients being treated in the same hospital as infected service
members-patients already weakened by such problems as organ failure,
immune system deficiency, or multiple traumatic wounds.

Two key issues seem behind the persistence of the outbreak. A number
of infectious disease specialists point to difficulties in completely
ridding hospital environments of acinetobacter. Doing so, they say,
requires more stringent cleaning than that typically sufficient to kill
other bacteria. Additionally, several express concern that policies on
antibiotic use differ at commands and hospitals along the casualty
evacuation chain.

Sometimes trying to err on the side of caution, doctors on the
frontline prescribe wide-spectrum antibiotics prior to determining if a
patient is actually carrying acinetobacter. In the long term, this has
created problems.

"I think antibiotic use is probably driving some of this," suggests
Petersen of the Comfort, "because when you keep people on prolonged
antibiotics unnecessarily, it lets them be colonized with worse and
worse bacteria."

In 2006, doctors at Walter Reed began successfully curbing
acinetobacter infections using an antibiotic called imipenem. Soon
thereafter, Endy recalls, frontline surgeons began using imipenem as a
prophylactic antibiotic-infusing it into injured service members even
when it was not clear the bacteria had colonized on the patients' skin
or invaded their wounds. The result, he says: "We started to see
increasing resistance to this antibiotic, resulting in the use of the
more toxic drug, colistin."

Wortmann at Walter Reed understands the urge of frontline providers to
"break out the big guns" right away, particularly when they know their
facilities are contaminated with acinetobacter. But he counsels
caregivers to first use antibiotics targeted toward more common
bacteria, treating for acinetobacter only when tests show a patient has
been colonized or infected. "When you give an antibiotic," he says,
"you'll kill most of the bacteria that's on that patient, but if a
bacteria either is resistant to that antibiotic or is able to rapidly
become resistant to that antibiotic, then it will grow because all the
other bacteria have been killed off."

Researchers in military laboratories and elsewhere are exploring
better means of fighting acinetobacter. Some are examining possible
uses of radiation. At Harvard, Anderson is experimenting with a dye
"painted" onto open wounds then activated with light. "Even the worst
strains that are resistant to multiple antibiotics, " he says, "will
succumb to the light-activated dye approach."

Policies on infection control and antibiotic use, meantime, remain
essentially unchanged from those in place when the war began. "There
are guidelines," says Wortmann, "and sort of loose oversight of the
practicing patterns of the physicians, but there is no one person that
says, 'Doctor Jones in Baghdad, you must do this.'"

Timothy Endy, the former Walter Reed physician, is among those who
believe that, in some measure, there should be. He urges defense
leaders to bring a more systematic approach to the fight-across
military service lines and command structures-citing "lessons that
should be learned from this outbreak but have not been implemented to
my knowledge."

A key reform he feels necessary, and past due: creating the means for
military services and the Department of Veterans Affairs to gather and
share real-time information on antibiotic-resistan t infections in
medical centers.

He also recommends application of unified policies on infection
control and prophylactic use of antibiotics- and advocates that the
service's most senior medical officers, employing a more global view
than physicians at single points along casualty evacuation routes, be
afforded authority to order clinical practice guidelines for infection
control.

Most important, he adds, in order for treatment rules to work more
swiftly than fast-adapting bacteria, such guidelines must be "executed
in the war theater without delay."

During 2004, the outbreak's worst point so far, some 30 percent of all
patients returning from Iraq and Afghanistan tested positive for
acinetobacter. Four years into the fight, up to 20 percent of those
returning wounded still face biological onslaught by this bloodstream
insurgent.

"That's what really held me back," says Marine Sergeant Emery. "That's
why I was laid up in the hospital for so long."

[Non-text portions of this message have been removed]