Published Date: 2006-10-18 00:00:00
Subject: PRO/EDR> Clostridium difficile, community acquired - USA (NC)
Archive Number: 20061018.2990
CLOSTRIDIUM DIFFICILE, COMMUNITY ACQUIRED - USA (NORTH CAROLINA)
A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases
Date: Tue, 17 Oct 2006
Source: Medscape.com [edited]
Cases of community-associated _Clostridium difficile_-associated diarrhea
(CA-CDAD) are increasing, and half of these cases are not attributable to
antibiotic use, finds a study presented here at the annual meeting of the
Infectious Diseases Society of America. In a related study, vancomycin was
found to be superior to metronidazole for the treatment of severe CDAD.
"In the healthcare setting, we know that it (_C. difficile_) is transmitted
from patient to patient," said L. Clifford McDonald, MD, a medical
epidemiologist at the CDC, and one of the first study's investigators. "The
question is how are patients getting it in the community."
Investigators defined CDAD as diarrhea in a patient with a positive _C.
difficile_ toxin assay. CA-CDAD was defined as CDAD onset in the community
or within 72 hours of hospital admission in a patient who had not had
inpatient health services during the previous 2 months.
Of a total of 1137 cases of CDAD reviewed at 6 North Carolina hospitals
between Jan and Dec 2005, nearly one in 5 (209, 18 percent) were acquired
in the community, with 50 percent of those cases not originating from
prescription of an antimicrobial, stressed Dr. McDonald. The median age of
patients was 60 years.
"These are remarkable figures (18 percent and 50 percent)," he said in an
interview with Medscape. "Exposure to antibiotics is the most important
modifiable risk factor for the development of the condition. If that is not
how it is developing, we can only speculate about how they are getting it.
Are they getting it from another person in the family, food, or the
environment? We don't know."
Dr. McDonald and colleagues matched the medical and laboratory records to
case controls of CA-CDAD at 4 Veteran Affairs hospitals (the remaining
institutions were one university hospital, and one regional hospital). In
statistical analysis, they found CA-CDAD cases were more likely to be
prescribed antimicrobials than control cases (adjusted odds ratio, 18.1; 95
percent confidence interval (CI), 6.3 - 51.9; P less than .0001) during the
previous 3 months. Cases were also more likely to to have underlying bowel
disease (adjusted odds ratio, 55.8; 95 percent CI, 5.1 - 6.7; P = .001) as
well as having had an outpatient visit to a healthcare facility (adjusted
odds ratio, 6.3; 95 percent CI, 1.9 - 20.3; P = .002).
In their initial findings from 2 hospitals, it appeared that the use of
proton pump inhibitors (PPIs) heightened the risk of acquiring CA-CDAD.
From the overall group of 6 hospitals, a total of 36 percent of case
patients were prescribed a PPI within 3 months prior to onset of symptoms.
Of the CA-CDAD cases, 23 percent were prescribed a PPI.
In the analysis of data from all institutions, they found use of a PPI to
not be a risk factor in the development of CA-CDAD (odds ratio, 1.337; 95
percent CI, 0.5 - 3.4; P = .50).
Daniel Musher, MD, an infectious disease specialist and head of infectious
diseases at Houston Veterans Affairs Medical Center in Texas and a
professor of medicine at the Baylor College of Medicine, said the rate of
CA-CDAD in the study raises the issue of spreading infections in the
community. He added that while the study did not find PPIs to be a risk
factor for developing CA-CDAD, several other studies have found that link.
[Byline: Louise Gagnon]
[The environmental source of _C. difficile_ spores is not clear but there
is no reason not to believe that the spores are quite ubiquitous. It would
be interesting to see if the genetic makeup of the community-acquired
isolates is different from those that are hospital-acquired and if
difference exist in those that cause disease in the absence of
antimicrobial pressure. - Mod.LL]