Immune Abnormalities in Patients Meeting New Diagnostic Criteria for
Chronic Fatigue Syndrome/Myalgic Encephalomyelitis
Brenu EW1,2*, Johnston S1,2, Hardcastle SL1,2, Huth TK1,2, Fuller K1,2, Ramos SB1,2, Staines DR2,3 and Marshall-Gradisnik SM1,2
1School of Medical Science, Griffith University, Gold Coast, Queensland, Australia
2The National Centre for Neuroimmunology and Emerging Diseases, Griffith Health Institute, Queensland, Australia
3Queensland Health, Gold Coast Public Health Unit, Robina, Gold Coast, Queensland, Australia
Background: Immunological abnormalities have been identified in Chronic Fatigue Syndrome/Myalgic
Encephalomyelitis patients fulfilling the 1994 Centers for Disease Control diagnostic criteria. Significant developments have been made to diagnostic criteria, but potential immunological markers have not been assessed in patients fulfilling these latest clinical requirements. Therefore, this study evaluated immunological parameters in patients that also fulfill the latest diagnostic criteria available known as the International Consensus Criteria.
Methods: The Immunological investigations including Natural Killer cell activity and phenotyping studies for
dendritic cells, neutrophils, B cells and regulatory T cells were performed on whole blood samples collected from all participants using flow cytometric protocols. The physical functioning of all participants was also evaluated using scores from the Short Form Health Survey, and the World Health Organization Disability Adjustment Schedule.
Results were compared according 1994 Centers of Disease Control and Prevention defined patients, and
International Consensus Criteria defined patients, and healthy controls.
Results: Natural killer cell activity was consistently and significantly decreased, and regulatory T cells were
significantly increased in both patient groups compared to healthy controls. Differences were found in human
neutraphil antigens and expression of natural killer cell receptors between patient groups. Highly significant
correlations were also found between physical status and some immune parameters in International Consensus
Criteria defined patients.
Conclusion: This preliminary investigation on different diagnostic criteria suggests that the International
Consensus Criteria may be more effective a detecting salient differences in the immune system.