Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2007 Mar;56(3):328-35.
doi: 10.1136/gut.2006.100198. Epub 2006 Aug 25.

Effect of chronic Giardia lamblia infection on epithelial transport and barrier function in human duodenum

Hanno Troeger  1 , Hans-Joerg Epple, Thomas Schneider, Ulrich Wahnschaffe, Reiner Ullrich, Gerd-Dieter Burchard, Tomas Jelinek, Martin Zeitz, Michael Fromm, Joerg-Dieter Schulzke
Affiliations

Effect of chronic Giardia lamblia infection on epithelial transport and barrier function in human duodenum

Hanno Troeger et al. Gut. 2007 Mar.

Abstract

Background: Giardia lamblia causes infection of the small intestine, which leads to malabsorption and chronic diarrhoea.

Aim: To characterise the inherent pathomechanisms of G lamblia infection.

Methods: Duodenal biopsy specimens from 13 patients with chronic giardiasis and from controls were obtained endoscopically. Short-circuit current (I(SC)) and mannitol fluxes were measured in miniaturised Ussing chambers. Epithelial and subepithelial resistances were determined by impedance spectroscopy. Mucosal morphometry was performed and tight junction proteins were characterised by immunoblotting. Apoptotic ratio was determined by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labelling staining.

Results: In giardiasis, mucosal surface area per unit serosa area was decreased to 75% (3%) of control, as a result of which epithelial resistance should increase. Instead, epithelial resistance of giardiasis biopsy specimens was decreased (19 (2) vs 25 (2) Omega cm(2); p<0.05) whereas mannitol flux was not significantly altered (140 (27) vs 105 (16) nmol/h/cm(2)). As structural correlate, reduced claudin 1 expression and increased epithelial apoptosis were detected. Furthermore, basal I(SC) increased from 191 (20) in control to 261 (12) microA/h/cm(2) in giardiasis. The bumetanide-sensitive portion of I(SC) in giardiasis was also increased (51 (5) vs 20 (9) microA/h/cm(2) in control; p<0.05). Finally, phlorizin-sensitive Na(+)-glucose symport was reduced in patients with giardiasis (121 (9) vs 83 (14) microA/h/cm(2)).

Conclusions: G lamblia infection causes epithelial barrier dysfunction owing to down regulation of the tight junction protein claudin 1 and increased epithelial apoptoses. Na(+)-dependent d-glucose absorption is impaired and active electrogenic anion secretion is activated. Thus, the mechanisms of diarrhoea in human chronic giardiasis comprise leak flux, malabsorptive and secretory components.

PubMed Disclaimer

Conflict of interest statement

Competing interests: None.

Comment in

References

    1. Furness B W, Beach M J, Roberts J M. Giardiasis surveillance‐United States, 1992–1997. MMWR CDC Surveill Summ 2000491–13. - PubMed
    1. Taylor D N, Houston R, Shlim D R. Etiology of diarrhea among travelers and foreign residents in Nepal. JAMA 19882601245–1248. - PubMed
    1. Rendtorff R C. The experimental transmission of human intestinal protozoan parasites: II. Giardia lamblia cysts given in capsules. Am J Trop Med Hyg 195459209 - PubMed
    1. Adam R D. The biology of Giardia spp. Microbiol Rev 199155706–732. - PMC - PubMed
    1. Nash T E, Herrington D A, Losonsky G A.et al Experimental human infections with Giardia lamblia. J Infect Dis 1987156974–984. - PubMed

Publication types

MeSH terms