Stomach Bug Mutates Into Medical Mystery: Antibiotics, Heartburn Drugs Suspected

[Guest guest]

Stomach Bug Mutates Into Medical Mystery

Antibiotics, Heartburn Drugs Suspected

 

By Rob Stein

Washington Post Staff Writer

Friday, December 30, 2005; A01

 

First came stomach cramps, which left Christina Shultz doubled over

and weeping in pain. Then came nausea and fatigue -- so overwhelming

she couldn't get out of bed for days. Just when she thought things

couldn't get worse, the nastiest diarrhea of her life hit --

repeatedly forcing her into the hospital.

 

Doctors finally discovered that the 35-year-old Hilliard, Ohio, woman

had an intestinal bug that used to be found almost exclusively among

older, sicker patients in hospitals and was usually easily cured with

a dose of antibiotics. But after months of treatment, Shultz is still

incapacitated.

 

" It's been a nightmare, " said Shultz, a mother of two young children.

" I just want my life back. "

 

Shultz is one of a growing number of young, otherwise healthy

Americans who are being stricken by the bacterial infection known as

Clostridium difficile -- or C. diff -- which appears to be spreading

rapidly around the country and causing unusually severe, sometimes

fatal illness.

 

That is raising alarm among health officials, who are concerned that

many cases may be misdiagnosed and are puzzled as to what is causing

the microbe to become so much more common and dangerous.

 

" It's a new phenomenon. It's just emerging, " said L. Clifford McDonald

of the federal Centers for Disease Control and Prevention in Atlanta.

" We're very concerned. We know it's happening, but we're really not

sure why it's happening or where this is going. "

 

It may, however, be the latest example of a common, relatively benign

bug that has mutated because of the overuse of antibiotics.

 

" This may well be another consequence of our use of antibiotics, " said

John G. Bartlett, an infectious-disease expert at Johns Hopkins

University in Baltimore. " It's another example of an organism that all

of a sudden has gotten a lot meaner and nastier. "

 

In addition, new evidence released last week suggests that the

enormous popularity of powerful new heartburn drugs may also be

playing a role.

 

The antibiotics Flagyl (metronidazole) and vancomycin still cure many

patients, but others develop stubborn infections like Shultz's that

take over their lives. Some resort to having their colon removed to

end the debilitating diarrhea. A small but disturbingly high number

have died, including an otherwise healthy pregnant woman who succumbed

earlier this year in Pennsylvania after miscarrying twins.

 

The infection usually hits people who are taking antibiotics for other

reasons, but a handful of cases have been reported among people who

were taking nothing, another unexpected and troubling turn in the

germ's behavior.

 

The infection has long been common in hospital patients taking

antibiotics. As the drugs kill off other bacteria in the digestive

system, the C. diff microbe can proliferate. It spreads easily through

contact with contaminated people, clothing or surfaces.

 

There are no national statistics, but the number of infections in

hospitals appears to have doubled from 2000 to 2003 and there may be

as many as 500,000 cases each year, McDonald said. Other estimates put

the number in the millions.

 

The emerging problem first gained attention when unusually large and

serious outbreaks began turning up in other countries. In Canada, for

example, Quebec health officials reported last year that perhaps 200

patients died in an outbreak involving at least 10 hospitals. Similar

outbreaks were reported in England and the Netherlands.

 

After the CDC began receiving reports of severe cases among hospital

patients in the United States -- and in people who had never, or just

briefly, been hospitalized -- it launched an investigation.

 

In the Dec. 8 issue of the New England Journal of Medicine, the CDC

reported that an analysis of 187 C. diff samples found that the

unusually dangerous strain that caused the Quebec cases was also

involved in outbreaks at eight health care facilities in Georgia,

Illinois, Maine, New Jersey, Oregon and Pennsylvania.

 

" This strain has somehow been able to get into hospitals widely

distributed across the United States, " said Dale N. Gerding of Loyola

University in Chicago, who helped conduct the analysis. " We're not

sure how. "

 

But scientists do have a few clues. The dangerous strain has mutated

to become resistant to a class of frequently used antibiotics known as

fluoroquinolones. That means anyone taking those antibiotics for other

reasons would be particularly prone to contract C. diff .

 

" Because this strain is resistant, it can take advantage of that

situation and establish itself in the gut, " Gerding said.

 

Experts said the resistant germ's proliferation offers the latest

reason why people should use antibiotics only when necessary, to

reduce both their risk for C. diff and the chances that other microbes

will mutate into more dangerous forms.

 

" That's one theory for what's happening here, " said J. Thomas Lamont

of Harvard Medical School. " If we reduce the number and amount of

antibiotics given for trivial infections like colds and stuffy noses,

we'd all be a lot better off. "

 

Overuse of antibiotics can make germs more dangerous by killing off

susceptible strains, leaving behind those that by chance have mutated

to become less vulnerable to the drugs. The resistant strains then

become dominant.

 

In addition to being resistant, the dangerous C. diff strain also

produces far higher levels of two toxins than do other strains, as

well as a third, previously unknown toxin. That would explain why it

makes people so much sicker and is more likely to kill. In Quebec, C.

diff killed 6.9 percent of patients -- which is much higher than the

disease's usual mortality rate -- and was a factor in more than 400

deaths.

 

Adding to the alarm is evidence that the infection is occurring

outside of hospitals. When the CDC began looking for such cases

earlier this year, investigators quickly identified 33 cases in New

Hampshire, New Jersey, Ohio and Pennsylvania, including 23 people who

had never been in the hospital and 10 women who had been hospitalized

only briefly to deliver a baby, the agency reported this month. Eight

of the patients had never taken antibiotics.

 

" This is the first time we've started to see this not only in people

who have never been in the hospital but also in those who are

otherwise perfectly healthy and have not even taken antibiotics, "

McDonald said.

 

" It's probably going on everywhere, " he said.

 

It remains unclear whether the cases occurring outside the hospital

are being caused by the same dangerous strain.

 

" We don't really know what's going on here, " McDonald said. " We know

it's changing in some ways; we know it's changing the kinds of

patients it's attacking, and we know it's causing more severe disease.

But we don't know exactly why. "

 

Canadian researchers, however, have found one possible culprit:

popular new heartburn drugs. Patients taking proton pump inhibitors,

such as Prilosec and Prevacid, are almost three times as likely to be

diagnosed with C-diff , the McGill University researchers reported in

the Dec. 21 issue of the Journal of the American Medical Association.

And those taking another type called H2-receptor antagonists, such as

Pepcid and Zantac, are twice as likely. By suppressing stomach acid,

the drugs may inadvertently help the bug, the researchers said.

 

Whatever the cause, the infection often resists standard treatment.

That is what happened to Shultz, who had been taking antibiotics to

help clear up her acne when C. diff hit in June. Because the bacterium

can hibernate in protective spores, patients can be prone to

recurrences. It can take multiple rounds of antibiotics -- or

sometimes infusions of antibodies or ingesting competing organisms

such as yeast or the bacteria found in yogurt -- to finally cure them.

 

" I'm trying to stay positive, " Shultz said. " People tell me it does go

away and I will get rid of it someday. I'm looking forward to getting

my life back, but I'm not convinced I'll ever be normal again. "

 

© 2005 The Washington Post Company

 

http://www.washingtonpost.com/wp-dyn/content/article/2005/12/29/AR2005122901575.\

html