group, 'Severity of Giardia infection associated with post-infectious
fatigue and abdominal symptoms two years after', which can be found
at- http://www.biomedcentral.com/1471-2334/9/206 . A newspaper article
follows the abstract.
---------------------------------------------------------------------------=
----------
http://gut.bmj.com/content/early/2011/08/31/gutjnl-2011-300220.short?rss=3D=
1
fulltext- http://press.psprings.co.uk/gut/september/gut300220.pdf
Irritable bowel syndrome and chronic fatigue 3 years after acute
giardiasis: historic cohort study
Knut-Arne Wensaas, Nina Langeland, Kurt Hanevik, Kristine M=F8rch, Geir
Egil Eide, Guri Rortveit
Gut doi:10.1136/gutjnl-2011-300220
ABSTRACT
Background Giardia lamblia is a common cause of gastroenteritis
worldwide, but there is limited knowledge about the long-term
complications.
Objective To estimate the relative risk of irritable bowel syndrome
(IBS) and chronic fatigue 3 years after acute giardiasis.
Design Controlled historic cohort study with 3 years=92 follow-up. Data
collected by mailed questionnaire.
Setting Waterborne outbreak of giardiasis in the city of Bergen, Norway.
Participants 817 patients exposed to Giardia lamblia infection
verified by detection of cysts in stool samples and 1128 matched
controls.
Main outcome measures IBS and chronic fatigue.
Results The prevalence of IBS in the exposed group was 46.1%, compared
with 14.0% in the control group, and the adjusted RR=BC3.4 (95% CI 2.9
to 3.8). Chronic fatigue was reported by 46.1% of the exposed group
and 12.0% of the controls, the adjusted RR was 4.0 (95% CI 3.5 to
4.5). IBS and chronic fatigue were associated and the RR for the
exposed group of having a combination of the two outcomes was 6.8 (95%
CI 5.3 to 8.5). The RR was also increased for having just one of the
two syndromes, 1.8 for IBS (95% CI 1.4 to 2.3) and 2.2 for chronic
fatigue (95% CI 1.7 to 2.8).
Conclusions Infection with Giardia lamblia in a non-endemic area was
associated with a high prevalence of IBS and chronic fatigue 3 years
after acute illness, and the risk was significantly higher than in the
control group. This shows that the potential consequences of
giardiasis are more serious than previously known. Further studies are
needed, especially in areas where giardiasis is endemic.
---------------------------------------------------------------------------=
--------
Infectious Diseases
Nearly Half of Giardiasis Patients Report Fatigue or IBS at 3 Years
By: JENNIE SMITH, Internal Medicine News Digital Network
People exposed to the protozoan Giardia lamblia are at increased risk
of having irritable bowel syndrome and chronic fatigue years after
their gastrointestinal infections have been treated, a team of
Norwegian researchers has found.
Although other types of acute gastrointestinal infections have been
associated with ongoing disorders including both fatigue and irritable
bowel syndrome (IBS), the finding challenges the assumption that acute
giardiasis, once treated, does not cause long-term complications.
Among a cohort of people who became ill during a 2004 outbreak of
giardiasis in the Norwegian city of Bergen, nearly half reported
having chronic fatigue, IBS, or both 3 years later. Prescription data
from the time of the outbreak, which was traced to a contaminated
reservoir, suggested that the vast majority of those affected had been
treated with metronidazole. Giardiasis is not endemic in Norway.
For their research, published online Sept. 12 in the journal Gut
(doi:10.1136/gutjnl-2011-300220), Dr. Knut-Arne Wensaas of the
University of Bergen and Uni Health in Bergen, and his colleagues,
collected data using validated questionnaires from 817 patients who
had laboratory-confirmed G. lamblia infection in 2004, and 1,128 age-
and sex-matched controls (mean age, 36; about 66% female) not infected
in that outbreak.
Of the exposed cases, 46.1% reported IBS at 3 years, compared with 14%
in the control group, for a relative risk of 3.4 (95% CI, 2.9-3.8)
after adjustment for potential confounding factors. The same
percentage =96 46.1% =96 of the exposed group reported chronic fatigue,
compared with 12% of controls (adjusted RR, 4.0; 95% CI, 3.5-4.5).
Despite the study=92s observational design, the association between
prior infection and the two disorders was seen as so strong, Dr.
Wensaas said in an interview, that "it suggests a causal relationship"
that warrants further investigation.
In the exposed group, 62.6% of those with IBS had chronic fatigue, as
did 30.6% of those without IBS, compared with 32% and 9% for controls.
That the two disorders, IBS and chronic fatigue, were found to occur
together more frequently among those with previous giardiasis
suggested that there could be commonalities in the pathogenesis of
giardiasis, IBS, and chronic fatigue. One possible link, the
researchers hypothesized, is an immune response involving T
lymphocytes.
While a majority of cases were women, sex was not seen as an effect
modifier for IBS or for chronic fatigue. The prevalence of IBS was
higher among women than men in both the exposed group (48.9% vs.
40.8%) and the control group (15.9% vs. 10.4%).
The authors noted that their definition of IBS was based on the Rome
III criteria: "recurrent abdominal pain or discomfort at least 3 days
a month in the past 3 months and associated with at least two of three
criteria related to defecation (onset associated with a change in
frequency or form of stool, or improvement with defecation)."
Dr. Wensaas said that the idea for the study came in part from his and
his colleagues=92 clinical observations treating patients in Bergen in
the years following the outbreak. A previous study, by another
research team, had also looked at the same outbreak and outcomes at a
2-year end point (Trans. R. Soc. Trop. Med. Hyg. 2009;103:530-2).
Dr. Wensaas, a general practitioner, said that not only had a large
number of patients presented with fatigue and/or IBS following their
giardiasis infections, but that they continued to have these symptoms
well past the 3-year end point of the study, suggesting that the
effects could continue even longer. Dr. Wensaas pointed to one
Canadian study that found an elevated risk for IBS at 8 years after
acute bacterial gastroenteritis (Gut 2010;59:605-11).
The investigators acknowledged as a weakness of their study the
potential for selection bias inherent in its observational design and
use of questionnaires. "There is a possibility that those having had
acute giardiasis will be more aware of symptoms and more likely to
find them abnormal than the controls, and thus report more
complaints," they wrote, noting also that the city of Bergen had
originally compensated those affected by the outbreak, potentially
encouraging exaggerated complaints.
An additional weakness reported was that chronic giardiasis could not
be ruled out among respondents.
Dr. Wensaas and his colleagues received funding for their study from
the city of Bergen and the Norwegian Medical Association=92s Funds for
Research in General Practice; none of the study authors said they had
relevant financial disclosures.
---------------------------------------------
Send posts to CO-CURE@listserv.nodak.edu
Unsubscribe at http://www.co-cure.org/unsub.htm
Select list topic options at http://www.co-cure.org/topics.htm
---------------------------------------------
Co-Cure's purpose is to provide information from across the spectrum of
opinion concerning medical, research and political aspects of ME/CFS and/or
FMS. We take no position on the validity of any specific scientific or
political opinion expressed in Co-Cure posts, and we urge readers to
research the various opinions available before assuming any one
interpretation is definitive. The Co-Cure website <www.co-cure.org> has a
link to our complete archive of posts as well as articles of central
importance to the issues of our community.
---------------------------------------------
