Immunophenotyping in post-giardiasis functional gastrointestinal disease and chronic fatigue syndrome

Abstract

BackgroundA 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.Methods48 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.ResultsIn 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.ConclusionPatients 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.

Irritable Bowel Syndrome and Chronic Fatigue 6 Years After Giardia Infection: A Controlled Prospective Cohort Study

“…All positive cases identified were successfully treated [ 14 ], and the carrier status in the exposed general population was very low [ 28 ]. Five years after the outbreak, chronic giardiasis was assessed in this cohort by polymerase chain reaction of stool samples from 53 exposed persons with long-term CF and/or IBS and 20 exposed persons without sequelae, and none were found to be positive [ 29 , 30 ]. We therefore are convinced that the prevalence of chronic giardiasis in the exposed group is very low.…”

Chronic fatigue syndrome 5 years after giardiasis: differential diagnoses, characteristics and natural course

“…In a recent report from the present cohort investigating previously reported markers of immune dysfunction in CFS, a decreased level of natural killer cells was found among CFS patients, suggesting a possible immunological abnormality that should be investigated further [29]. …”

Screening NK-, B- and T-cell phenotype and function in patients suffering from Chronic Fatigue Syndrome

“…Similarly, B-cell function [24], B-cell mediated autoimmunity or unbalanced cytokine network have been linked to CFS [9,25-27] again with inconclusive results. Altered numbers of NK subsets, defined by CD56 or CD16 expression, and an impaired NK-cell lytic activity have been more consistently associated with CFS [24,28-32], although controversial data have been also reported [33] and a consensus in relevant NK cell markers is still lacking.…”