Monitoring a Hypothetical Channelopathy in Chronic Fatigue Syndrome:
Preliminary Observations

J of Chronic Fatigue Syndrome, Vol. 11(1) 2003

Jo Nijs, MSc; Christian Demanet, MD, PhD; Neil R. McGregor, BDS,
MDSc, PhD; Pascale De Becker, PhD; Michel Verhas, MD, PhD; Patrick
Englebienne, PhD; Kenny De Meirleir, MD, PhD

Jo Nijs and Pascale De Becker are affiliated with the
Department of Human Physiology, Faculty of Physical Education and Physical
Therapy, Vrije Universiteit Brussel, Belgium.

Christian Demanet is affiliated with the Division of Hematology and
Immunology, Academic Hospital, Vrije Universiteit Brussel, Belgium.

Neil R. McGregor is affiliated with the Collaborative Pain Research Unit,
Depart- ment of Biological Sciences, Faculty of Science, University of
Newcastle, Callaghan, New South Wales, Australia.

Michel Verhas and Patrick Englebienne are affiliated with the Department of
Nuclear Medicine, Brugmann Hospital/Academic Hospital. Vrije Universiteit
Brussel and Universite Libre Bruxelles (V.U.B-U.L.B.), Brussels, Belgium.

Kenny De Meirleir is affiliated with the Department of Human Physiology,
Faculty of Physical Education and Physical Therapy, and the Fatigue Clinic,
Vrije Universiteit Brussel, Belgium.

Address correspondence to: Jo Nijs, Vakgroep MFYS, AZ-VUB KRO gebouw-1,
Laarbeeklaan 101, 1090 Brussel-Belgium (E-mail: mailto:Jo.Nijs@vub.ac.be ).


ABSTRACT.
This study was aimed at monitoring of a previously suggested channelopathy
in Chronic Fatigue Syndrome, and at searching for possible explanations by
means of immune system characteristics. Twenty-seven CFS patients and 20
age and sex matched healthy volunteers were recruited. RNase L-ratio,
percent of the norm of whole body potassium content, serum electrolytes
(sodium. calcium and potassium), immune cells, blood cell count and
erythrocyte sedimentation rate were determined. More than fifty percent of
our patients presented with abnormal whole body potassium content. Eight
patients had increased, while six had depleted potassium content.
Discriminant function analysis revealed that the CFS patients and control
subjects could be differentiated on immunophenotyping with the predominant
cell differences being the increase in CDI9+ CD5+ (mature B-) cells and the
decrease in CD3- CDI6+ CDS6+ (NK) cells in both the percentage and count
distributions. The fall in NK-cells was very strongly associated with
increases in the RNase L-ratio and falls in serum calcium levels. In
addition, four patients with low serum calcium levels showed lower whole
body potassium levels. In conclusion, these observations suggest a
channelopathy in a subset of CFS patients, probably induced by the
deregulated 2-5A RNase L antiviral pathway.


KEYWORDS. Chronic fatigue syndrome, channelopathy, immunity, RNase L,
potassium


INTRODUCTION .
Chronic Fatigue Syndrome is characterized by numerous symptoms, but there
does not appear to be a single underlying cause for all patients. Indeed,
Holmes (1988) (1) and Fukuda (1994) (2) CDC-criteria gave rise to a
heterogeneous patient-group. This heterogeneity therefore re- quires the
investigators to delineate those features that may be causative as compared
to those features that may result from secondary host responses or
co-morbid disease.

There is a growing international consensus to differentiating Chronic
Fatigue Syndrome into clinically relevant subcategories that may represent
either different disease states or to differentiate the potential co-
morbid illnesses. Therefore, assessment of the deregulation of the 2-5A
synthetase/RNase L antiviral pathway (3) and its associations with
biochemical, immune and symptom changes is of prime importance. A recent
report (4) suggests possible associations between the deregulated pathway
and a channelopathy (5,6,7) in chronic fatigue syndrome. Thus an assessment
of the associations between the RNase L-ratio and electrolyte changes may
allow determination of any association between RNase L-anomaly and a
potential channelopathy as assessed by a serum electrolyte panel and whole
body potassium determination. We present here a study of a small sample of
CFS patients (and matched healthy controls) in which we use uni- and
multivariate analyses to assess any possible associations between the RNase
L-ratio, electrolytes, biochemical and immunological parameters.

© 2003 by The Haworth Press, Inc. All rights reserved.