Beds lie empty in the emergency room of Tulane University Hospital in New Orleans February 14, 2006. (Lee Celano/Reuters)

WASHINGTON (Reuters) -
Federal government figures show a
steep spike in U.S. cases of a common but serious infection
that gives hospital patients sometimes deadly diarrhea and
blood poisoning.

They show a 200 percent increase in the number of hospital
patients infected with Clostridium difficile, or C. difficile,
from 2000 to 2005.

The U.S. Agency for Healthcare Research and Quality tracked
more than 2 million cases of C. difficile in U.S. hospitals
between 1993 and 2005. Its figures show the latest jump follows
a 74 percent rise in the number of cases from 1993 to 2000.

Clostridium can cause mild diarrhea or an often deadly
illness that can be treated only by completely removing the
colon. Two out of three infected hospital patients in 2005 were
elderly, the AHRQ found.

People carry C. difficile on their hands, like other
bacteria, and spread it when they touch objects, including
hospital beds, equipment and doors. It forms spores that are
not killed by alcohol hand sanitizers but can be destroyed with
bleach.

Incontinent patients and those who have been treated for
the infection before are among the likely carriers, experts
have found. Other recent studies have shown C. difficile
bacteria are commonly spread by unhygienic practices in
hospitals.

In Britain, doctors have been discouraged from wearing
white coats after studies suggested their long sleeves might
pick up and spread the bugs.

The AHRQ study found that patients with C. difficile were
hospitalized almost three times longer than uninfected patients
and 9.5 percent died in hospital compared with 2.1 percent of
patients overall.

The AHRQ team uses statistics from the Nationwide Inpatient
Sample, a database of hospital inpatient stays that covers 90
percent of all discharges in the United States.

The most commonly used antibiotic for C. difficile is
metronidazole, but some severe and antibiotic-resistant forms
must be treated with vancomycin.

Like other bacteria, C. difficile can also acquire
resistance to vancomycin, making treatment difficult or
impossible.

(Reporting by Maggie Fox; Editing by Eric Walsh)