Immunophenotyping in post-giardiasis functional gastrointestinal disease and chronic fatigue syndrome
1 Institute of Medicine, University of Bergen, Bergen, N-5021, Norway
2 Centre for Tropical Infectious Diseases, Haukeland University Hospital, Bergen, N-5021, Norway
3 Department of Immunology and Transfusion Medicine, Haukeland University Hospital, Bergen, Norway
4 The Gade Institute, University of Bergen, Bergen, Norway
5 Department of Neurology, Haukeland University Hospital, Bergen, Norway
6 Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
7 Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
BMC Infectious Diseases 2012, 12:258 doi:10.1186/1471-2334-12-258Published: 14 October 2012
A Giardia outbreak was associated with development of post-infectious functional gastrointestinal disorders (PI-FGID) and chronic fatigue syndrome (PI-CFS). Markers of immune dysfunction have given conflicting results in CFS and FGID patient populations. The aim of this study was to evaluate a wide selection of markers of immune dysfunction in these two co-occurring post-infectious syndromes.
48 patients, reporting chronic fatigue in a questionnaire study, were clinically evaluated five years after the outbreak and grouped according to Fukuda criteria for CFS (n=19) and idiopathic chronic fatigue (n=5) and Rome II criteria for FGIDs (n=54). 22 Giardia exposed non-fatigued individuals and 10 healthy unexposed individuals were recruited as controls. Peripheral blood lymphocyte subsets were analyzed by flow cytometry.
In peripheral blood we found significantly higher CD8 T-cell levels in PI-FGID, and significantly lower NK-cell levels in PI-CFS patients. Severity of abdominal and fatigue symptoms correlated negatively with NK-cell levels. A tendency towards lower T-cell CD26 expression in FGID was seen.
Patients with PI-CFS and/or PI-FGID 5 years after Giardia lamblia infection showed alterations in NK-cell and CD8-cell populations suggesting a possible immunological abnormality in these conditions. We found no significant changes in other markers examined in this well-defined group of PI-CFS and PI-FGID elicited by a gastrointestinal infection. Controlling for co-morbid conditions is important in evaluation of CFS-biomarkers.