Chapter 8

NEUROLOGY

 

 

Brainstem perfusion is impaired in chronic fatigue syndrome

Costa DC, Tannock C, Brostoff J. 

Institute of Nuclear Medicine, University College London Medical School, London, UK.

Quarterly Journal of Medicine 1995; 88(11): 767-73.

Abstract: We looked for brain perfusion abnormalities in patients with myalgic encephalomyelitis /chronic fatigue syndrome (ME/CFS).  An initial pilot study revealed widespread reduction of regional brain perfusion in 24 ME/CFS patients, compared with 24 normal volunteers.  Hypoperfusion of the brainstem (0.72 ± 0.05 vs. 0.80 ± 0.04, p <0.0001) was marked and constant.  We then tested whether perfusion to the brainstem in ME/CFS patients differs from that in normals, patients with major depression, and others with epilepsy.  Data from a total of 146 subjects were included in the present study: 40 normal volunteers, 67 patients with ME/CFS (24 in the pilot study, 16 with no psychiatric disorders, 13 with ME/CFS and depression, 14 with ME/CFS and other psychiatric disorders), 10 epileptics, 20 young depressed patients and 9 elderly depressed individuals.  Brain perfusion ratios were calculated using 99Tcm-hexamethylpropylene amine oxime (99Tcm-HMPAO) and single-photon emission tomography (SPECT) with a dedicated three-detector gamma camera computer/system (GE Neurocam).  Brain-stem hypoperfusion was confirmed in all ME/CFS patients.  Furthermore, the 16 ME/CFS patients with no psychiatric disorders and the initial 24 patients in the pilot study showed significantly lower brainstem perfusion (0.71 ± 0.03) than did depressed patients (0.77 ± 0.03; ANOVA, p < 0.0001).   Patients with ME/CFS have a generalized reduction of brain perfusion, with a particular pattern of hypoperfusion of the brainstem.

 

Vestibular function test anomalies in patients with chronic fatigue syndrome.

Ash-Bernal R; Wall C 3rd; Komaroff AL; Bell D; Oas JG; Payman RN; Fagioli LR
Department of Otology and Laryngology, Massachusetts Eye and Ear Infirmary,

Harvard Medical School, Boston, Mass. USA.

Acta Otolaryngol 1995 Jan;115(1):9-17   (ISSN: 0001-6489)

Chronic fatigue syndrome (CFS) is distinguished by the new onset of debilitating fatigue that lasts at least 6 months, concomitant with other symptoms to be described later.  Many CFS patients complain of disequilibrium, yet the exact type of the balance dysfunction and its function and its location (peripheral vs. central) have not been described.  Herein we report results of vestibular function testing performed on 11 CFS patients.  These results revealed no predominant pattern of abnormalities.  Patients typically performed below average in dynamic posturography testing, with a significant number of falls in the tests requiring subjects to depend heavily on the vestibular system.  One patient had abnormal caloric testing, while 3 had abnormally low earth vertical axis rotation (EVA) gains at the higher frequencies tested.  As a group, the average gain of EVA was significantly lower than normals in the 0.1 - 1.0 Hz range (p < 0.05).   In earth horizontal axis rotation, the CFS group had a higher than normal bias value for the optokinetic (OKN) and eyes open in the dark conditions (p < 0.05), but had normal scores during visual vestibular reflex testing.  Five of the 11 subjects had an abnormal OKN bias build up over the course of the run, equal to or actually exceeding the 60 degrees/s target velocity by as much as 14 degrees/s.   Altogether, these results are more suggestive of central nervous system deficits than of peripheral vestibular disfunction.

Unique NLM Identifier: 95282610  Grant ID: DC00290-DC-NIDCD; U01 AI32246-AI-NIAID 

 

Prolongation of Central Motor Conduction Time in Chronic Fatigue Syndrome

 Arnold Hilgers, Johannes Frank and Petra Frank
Journal of Chronic Fatigue Syndrome  1998 vol 4 no 2 page 23-32

We compared the central motor conduction time (CMCT) obtained by magnetic stimulation of the central nervous system (CNS) of 181 patients who fulfilled the criteria (see Fukuda 1994) for CFS with those of 27 healthy control subjects.  A cortical and a cervical stimulation was performed on each person under standardised conditions, and the motor evoked potentials (MEP) either from Musculus Abductor Pollicis Brevis (M. APB) or from Musculus Abductor Digit Minimi (M. ADM) was recorded.
For the CFS patients a significant prolongation of the central motor conduction time (M.APB right: p<0.0001; M ADP left: p<0.00005; M. ADM right : p<0,00005; M. ADM left: p<0.005) was observed compared to controls.  The results presented in this study suggest a central nervous systems dysfunction in CFS. 

 

Relationship Between SPECT Scans and Buspirone Tests in Patients with ME/CFS

 John Richardson, Durval Campos Costa
Journal of Chronic Fatigue Syndrome  1998 vol.4 no.3 pp23-38

The purpose of this exercise was to study the relationship between the detail shown on the SPECT brain scans with those seen in the buspirone tests.

Thirty-nine patients are included in this study.  These patients were selected from a large number who had been referred to Dr. Richardson from various parts of the country by their doctors because of a tentative diagnosis of ME/CFS.  All the selected patients were confirmed by Dr. Richardson as suffering from ME/CFS taking into account the subjective scoring methods, clinical examination, virology and buspirone tests.

This study is an attempt to link together the results of the previously described techniques to investigate possible areas of impaired cellular function in brain which may have purely neuroneural effects or possibly neurohormonal effects.

All patients within this study displayed hypoperfusion in some brain area as shown by their SPECT scans.    Thirty-five (90%) showed hypoperfusion in the regions comprising: Twenty-four (62%) in the Brain Stem; Twenty (51%) in the Caudate Nuclei.  Nine (23%) showed hypoperfusion in both Brain Stem and Caudate Nuclei regions.    Thirty (77%) cases demonstrated hyperprofusion in the regions comprising: Twenty-four (62%) in the Temporal Lobes; Twelve (31%) in the Parietal Lobes; Nine (23%) in the Frontal Lobes.

The significance of these results is to confirm that there is actual evidence of neurological dysfunction which results in the continuing morbidity in these ME/CFS patients.

The completion of this buspirone test and SPECT scan can be deemed to be basic complementary evidence for the positive diagnosis of ME/CFS.

 

Chronic fatigue syndrome--aetiological aspects

Dickinson CJ
Wolfson Institute , St. Bartholomew's & Royal London School of Medicine & Dentistry, London, UK.

Eur J Clin Invest 1997 Apr;27(4):257-67   (ISSN: 0014-2972)

The chronic fatigue syndrome (CFS) has been intensively studied over the last 40 years, but no conclusions have yet been agreed as to its cause. Most cases nowadays are sporadic. In the established chronic condition there are no consistently abnormal physical signs or abnormalities on laboratory investigation. Many physicians remain convinced that the symptoms are psychological rather than physical in origin. This view is reinforced by the emotional way in which many patients present themselves. The overlap of symptoms between CFS and depression remains a source of confusion and difficulty. But even if all CFS patients were rediagnosed as depressives, this would not negate the possibility of an underlying organic cause for the condition, in view of the growing evidence that depression itself has a physical cause and responds best to physical treatments. There is some evidence both for active viral infection and for an immunological disorder in the CFS. Many observations suggest that the syndrome could derive from residual damage to the reticular activating system (RAS) of the upper brain stem and/or to its cortical projections. Such damage could be produced by a previous viral infection, leaving functional defects unaccompanied by any gross histological changes. In animal experiments activation of the RAS can change sleep state and activate or stimulate cortical functions. RAS lesions can produce somnolence and apathy. Studies by modern imaging techniques have not been entirely consistent, but many magnetic resonance imaging (MRI) studies already suggest that small discrete patchy brain stem and subcortical lesions can often be seen in CFS. Regional blood flow studies by single photon-emission computerized tomography (SPECT) have been more consistent. They have revealed blood flow reductions in many regions, especially in the hind brain. Similar lesions have been reported after poliomyelitis and in multiple sclerosis--in both of which conditions chronic fatigue is characteristically present. In the well-known post-polio fatigue syndrome, lesions predominate in the RAS of the brain stem. If similar underlying lesions in the RAS can eventually be identified in CFS, the therapeutic target for CFS would be better defined than it is at present. A number of logical approaches to treatment can already be envisaged.

Unique NLM Identifier: 97279998  ; REVIEW (168 references); REVIEW, TUTORIAL 

 

 

Elevated Plasma Prolactin and EEG Slow Wave Power in Post-Polio Fatigue: Implications for a Dopamine Deficiency Underlying Post-Viral Fatigue Syndromes

 Richard L Bruno, Susan Creange, Jerald R Zimmerman and Nancy M Frick HarvestCtr@AOL.COM
 Journal of Chronic Fatigue Syndrome  1998 vol.4 no.2 page 61-75

To test the hypothesis that plasma prolactin and electroencephalographic (EEG) slow wave activity are correlated with fatigue, 33 polio survivors without medical or psychologic comorbidities were studied.  Subjects were administered the Post-Polio Fatigue Questionnaire (PFQ) and had resting measurement of both plasma prolactin and bilateral temporal-occipital power across the EEG frequency spectrum.  Typical daily fatigue severity on the PFQ was significantly correlated with daily difficulty with attention, staying awake and motivation, but not with measures of acute polio severity or the number of limbs affected by late-onset Post-Polio Sequelae symptoms.  Prolactin was significantly correlated with daily fatigue severity on the PFQ (r = .39; p <0.5).  EEG power was equal between the two hemispheres across all frequency bands.  However, EEG slow wave power in the right hemispheres was significantly correlated with daily fatigue severity and prolactin level (r = .37; p <.05).  Using multiple linear regression, age at acute polio, frequency of difficulty with attention on the PFQ, prolactin and right hemisphere slow wave power predicted 72% of the variance of the daily fatigue severity rating (r = .85; p < .0001).  These data suggest that increased prolactin secretion and EEG slowing are related to the severity of post-polio fatigue, findings similar to those in patients with acute paralytic and non-paralytic poliomyelitis and with chronic fatigue syndrome.  A primary role is suggested for a dopamine deficiency (versus serotonergic receptor supersensitivity) underlying impaired cortical activation and the symptoms associated with putative post-viral fatigue syndromes.

 

 

Cortical motor potential alterations in chronic fatigue syndrome.

Gordon R;  Michalewski HJ;  Nguyen T;  Gupta S;  Starr A
Department of Neurology, University of California, Irvine, Med. Surge I, Room 154, Irvine, CA 92697 USA.

Int J Mol Med 1999 Nov;4(5):493-9   (ISSN: 1107-3756)

Premovement, sensory, and cognitive brain potentials were recorded from patients with Chronic Fatigue Syndrome (CFS) in four tasks: i) target detection, ii) short-term memory, iii) self-paced movement, and iv) expectancy and reaction time (CNV). Accuracy and reaction times (RTs) were recorded for tasks i, ii, and iv. Results from CFS patients were compared to a group of healthy normals. Reaction times were slower for CFS patients in target detection and significantly slower in the short-term memory task compared to normals. In target detection, the amplitude of a premovement readiness potential beginning several hundred milliseconds prior to stimulus onset was reduced in CFS, whereas the poststimulus sensory (N100) and cognitive brain potentials (P300) did not differ in amplitude or latency. In the memory task, a negative potential related to memory load was smaller in CFS than normals. The potentials to self-paced movements and to expectancy and RT (CNV) were not different between groups. The findings in CFS of slowed RTs and reduced premovement-related potentials suggest that central motor mechanisms accompanying motor response preparation were impaired in CFS for some tasks. In contrast, measures of neural processes related to both sensory encoding (N100) and to stimulus classification (P300) were normal in CFS.

Unique NLM Identifier: 20006356   Grant ID: RO1 AI-34250-AI-NIAID



Increased Resting Energy Expenditure in the Chronic Fatigue Syndrome

Walter S. Watson, PhD Donald C. McMillan, PhD Abhijit Chaudhuri, DM, MD Peter O. Behan, MD, DSc     

 the Nuclear Medicine Department, Southern General Hospital   the University Department of Surgery. Royal Infirmary

 Department of Neurology, University of Glasgow, Glasgow, Scotland. UK. (E-mail: wswatson@compuserve.com).

Journal of Chronic Fatigue Syndrome  Vol.4 (4) 1998

It has been suggested that resting energy expenditure may be raised in chronic fatigue syndrome due to an upregulation of transmembrane ion transport. We measured resting energy expenditure by indirect calorimetry in 11 women with chronic fatigue and in 11 healthy women. Total body potassium, by whole body counting, and total body water, extracellular water and intracellular water, by a bioelectrical impedance method, were also measured.

When individual resting energy expenditure was predicted on the basis of total body potassium values for the chronic fatigue group, 5 out of 11 of these subjects had resting energy expenditure above the upper limit of normal as defined by the control group data. This is consistent with the hypothesis that there is upregulation of the sodium-potassium pump in chronic fatigue syndrome.

 

Impaired associative learning in chronic fatigue syndrome.

Servatius RJ; Tapp WN; Bergen MT; Pollet CA; Drastal SD; Tiersky LA; Desai P; Natelson BH       

New Jersey Medical School, Department of Neuroscience, East Orange 07019, USA.

Neuroreport  1998  Apr 20;9(6):1153-7    (ISSN: 0959-4965)

Patients with chronic fatigue syndrome (CFS) report cognitive difficulties (impaired attention, memory and reasoning).  Neuropsychological tests have failed to consistently find cognitive impairments to the degree reported by CFS patients.  We tested patients with CFS and sedentary controls in protocols designed to measure sensory reactivity and acquisition of the classically conditioned eyeblink response.  Patients with CFS exhibited normal sensitivity and responsivity to acoustic stimuli.  However, CFS patients displayed impaired acquisition of the eyeblink response using a delayed-type conditioning paradigm.  Sensitivity and responsivity to the airpuff stimulus were normal. In the absence of sensory/motor abnormalities, impaired acquisition of the classically conditioned eyeblink response indicates an associative deficit.  These data suggest organic brain dysfunction within a defined neural substrate in CFS patients.                                                             

Unique NLM Identifier: 98263991 Grant ID: UOI-AI32247-AI-NIAID             


Attention and information processing efficiency in patients with Chronic Fatigue Syndrome.

Michiels V; de Gucht V; Cluydts R; Fischler B
Free University of Brussels (VUB), Belgium.

J Clin Exp Neuropsychol   1999 Oct; 21(5):709-29   (ISSN: 0168-8634)

In this study a battery of attentional tests and a verbal memory task were administered to outpatients with Chronic Fatigue Syndrome (CFS) in order to evaluate aspects of attention that have not been explored in this group to date.  In addition, this study was designed to further examine memory function and to extend the few reports investigating the rate of cognitive processing independent of motor speed and the possibility of a modality-specific impairment of information processing.  Twenty-nine patients with CFS and 22 healthy controls matched for age, gender, intelligence, and education were included in this study.   The results show that patients with CFS do not seem to be impaired for modification of phasic arousal level, nor for visual selective attention requiring shifting of attention in the visuospatial field.  The results further support the presence of reduced information processing speed and efficiency, and strengthen the evidence of a global non-modality-specific attentional dysfunction in patients with CFS.   In this study the poor performance of patients with CFS on recall of verbal information was due to poor initial storage rather than to a retrieval failure.
 Unique NLM Identifier: 20042376 

 

 

Influence of exhaustive treadmill exercise on cognitive functioning in chronic fatigue syndrome.

La Manca JJ; Sisto SA; De Luca J; Johnson SK; Lange G; Pareja J; Cook S; Natelson BH
C.F.S. Cooperative Research Center, University of Medicine and Dentistry of New Jersey- New Jersey Medical School, Newark, USA.

Am J Med  1998 Sep 28; 105(3A):59S-65S   (ISSN: 0002-9343)

The purpose of this study was to determine the effect of exhaustive exercise on cognitive performance of patients with chronic fatigue syndrome (CFS) and sedentary healthy controls (CON).  Subjects were 19 women with CFS and 20 CON. A test battery consisting of 4 cognitive tests (CTB) was given pre-, immediately post-, and 24 hours post-treadmill exercise to exhaustion.  No differences were seen on the CTB pre-exercise. CFS patients improved at a slower rate than CON on the Symbol Digit Modalities Test (SDMT), Stroop Word Test (SWT), and Stroop Color Test (SCT).  When compared with CON, a lower number of correct responses was seen for the CFS immediately postexercise on the SDMT (61 +/- 3 vs 66 +/- 2), SWT (137 +/- 6 vs 146 +/- 6), and SCT (99 +/- 4 vs 107 +/- 3), and 24 hours postexercise on the SDMT (64 +/- 3 vs 69 +/- 2), SWT (134 +/- 7 vs 148 +/- 5), and SCT (101 +/- 4 vs 106 +/- 3).   We conclude that after physically demanding exercise, CFS subjects demonstrated impaired cognitive processing compared with healthy individuals.    

 Unique NLM Identifier: 99005145   Grant ID: U01 AI-32247-AI-NIAID 

 

Abnormal arginine-vasopressin secretion and water metabolism in patients with postviral fatigue syndrome.
 Bakheit AM, Behan PO, Watson WS, Morton JJ
Department of Neurology, University of Glasgow, Scotland

Acta Neurol Scand  1993 Mar; 87(3):234-8

Water metabolism and the responses of the neurohypophysis to changes in plasma osmolality during the water loading and water deprivation tests were studied in nine patients with postviral fatigue syndrome (PVFS) and eight age and sex-matched healthy control subjects.  Secretion of arginine-vasopressin (AVP) was erratic in these patients as shown by lack of correlation between serum and urine osmolality and the corresponding plasma AVP levels.  Patients with PVFS had significantly low baseline arginine-vasopressin levels when compared with healthy subjects.  Patients with PVFS as a group also showed evidence of increased total body water content.  These results may be indicative of hypothalamic dysfunction in patients with PVFS.

PMID: 8475696, UI: 93235541

 


Relationships of cognitive difficulties to immune measures, depression and illness burden in CFS.

Lutgendorf S, Klimas NG, Antoni M, Brickman A, Fletcher MA 

University of Miami School of Medicine, Miami, Florida, USA.

Journal of Chronic Fatigue Syndrome 1995; 1(2): 23-41.  

Abstract:  OBJECTIVE. We related the subjective assessment of cognitive difficulties with lymphocyte phenotypes, cell-mediated immunity (CMI), cytokine and neopterin levels in patients with chronic fatigue syndrome (CFS), in order to determine if CFS patients complaining of greater cognitive difficulties would show greater impairments in cell-mediated immunity and a greater degree of immune system dysregulation, and to determine if these cognitive difficulties would correlate with the other non-affective measures of CFS-associated illness burden.   We also assessed whether these relationships would hold independent of depression in two ways, by statistically covarying depression severity scores and by comparing subsets of CFS patients with and without a concurrent diagnosis of major depressive disorder.   DESIGN. A case series of CFS patients. 

SETTING. Outpatient tertiary referral clinic at the University of Miami School of Medicine, Miami, FL.  

PATIENTS. Consecutive sample of 65 patients who were referred as CFS to the University of Miami Diagnostic Immunology Clinic, who met the Centers for Disease Control and Prevention (CDC) criteria for diagnosis of CFS and consented to participate. 

MAIN MEASURES. Self-assessment of cognitive difficulties, depression and illness burden, clinician-assessed depression and CFS symptoms, lymphocyte phenotype, proliferative response to mitogens, serum levels of cytokines and neopterin. 

RESULTS. Among CFS patients, high Cognitive Difficulty Scale (CDS) scores were significantly related to lower lymphocyte proliferative responses to mitogens, higher neopterin levels, and higher CD4 and lower CD8 lymphocyte counts.  These relationships, with the exception of T cell subset percentages, were maintained when depression severity was used as a co-variate.  High CDS scores were also significantly related to lower Karnofsky scores, and greater illness burden as measured by the Sickness Impact Profile.  Evidence is presented that CFS patients with higher cognitive difficulty scores have more immune and clinical dysfunction than those with less cognitive difficulty, and that these relationships are independent of depression .  These observations provide support for the concept that although both cognitive difficulties and immunologic abnormalities, such as immune activation and impaired cell-mediated immunity, may represent secondary sequelae to the same event(s), they are not likey to be secondary sequelae to depression.  

 

 

Working memory deficits associated with chronic fatigue syndrome

BONNIE M. DOBBS a1 c1 , ALLEN R. DOBBS a1 and IVAN KISS a2
a1 Department of Psychology, University of Alberta, Edmonton, Alberta, Canada  a2 Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada
Journal of the International Neuropsychological Society (2001), 7:285-293

Cognitive impairments are among the most frequently reported and least investigated components of the chronic fatigue syndrome (CFS). As part of a multifaceted study of the CFS, the present study investigated the cognitive functioning of chronic fatigue patients. The performance of 20 CFS patients was compared to that of controls (N = 20) on 4 tests of working memory (WM). Digit Span Forward was used to assess the storage capacity of WM. Multiple aspects of central executive functioning were assessed using several standard measures: Digit Span Backward, and Trails A and Trails B. More recently developed measures of WM were used to assess control of processing under temporal demands (working memory task) and resistance to interference (a sustained attention task). Deficits were restricted to more demanding tasks, requiring resistance to interference and efficient switching between processing routines. The overall results clearly implicate deficits in the control aspects of central executive function in CFS.

 

Cardiovascular responses of women with chronic fatigue syndrome to stressful cognitive testing before and after strenuous exercise.
 LaManca JJ, Peckerman A, Sisto SA, DeLuca J, Cook S, Natelson BH.
C.F.S. Cooperative Research Center, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey

Psychosom Med 2001 Sep-Oct;63(5):756-64

OBJECTIVE: The purpose of this study was to compare the cardiovascular responses of patients with chronic fatigue syndrome (CFS) to healthy control subjects when performing stressful cognitive tasks before and after
strenuous exercise.  

METHOD:  Beat-by-beat blood pressure and electrocardiogram were recorded on 19 women with CFS and 20 healthy nonexercising (ie, sedentary) women while they performed cognitive tests before, immediately after, and 24 hours after incremental exercise to exhaustion.
RESULTS: Diminished heart rate (p <.01) and systolic (p <.01) and diastolic (p <.01) blood pressure responses to stressful cognitive testing were seen in patients with CFS when compared with healthy, sedentary controls. This
diminished stress response was seen consistently in patients with CFS across three separate cognitive testing sessions. Also, significant negative correlations between self-ratings of CFS symptom severity and cardiovascular
responses were seen (r = -0.62, p <.01).
CONCLUSIONS: Women with CFS have a diminished cardiovascular response to cognitive stress; however, exercise did not magnify this effect. Also, the data showed that the patients with the lowest cardiovascular reactivity had the highest ratings of CFS symptom severity, which suggests that the individual response of the patient with CFS to stress plays a role in the common complaint of symptoms worsening after stress.

PMID: 11573024

 

The symptoms of Chronic Fatigue Syndrome are related to abnormal  ion channel function

Peter O. Behan*, Abhijit Chaudhuri*, Walter S. Watson**, John Pearn***
*University Department of Neurology, Institute of Neurological Sciences and   **Department of Nuclear Medicine, Southern General Hospital, Glasgow (UK),   ***Department of Child Health, University of Queensland, Brisbane (Australia).

Presented at the American Association for Chronic Fatigue Syndrome Research Conference
October 10-11, 1998 -- Cambridge, Massachusetts

Objective:  Many symptoms of chronic fatigue syndrome (CFS), including severity of fatigue, are periodic, fluctuant and are inducible by physical and mental activities. Chest pain is a common symptom of CFS, like patients with syndrome X, an ion channel disorder. Symptoms in CFS such as fatigue, myalgia and headache bear striking resemblance with neurological disorders that affect  ion channel function, such as periodic paralysis and familial hemiplegic migraine. Maintenance of normal transmembrane ionic equilibrium is an active, energy-dependent process, and constitutes an important share of the resting energy expenditure (REE). We wanted to compare and contrast the clinical profile of CFS patients with other neurological disorders that are known to affect  ion channel function, and estimate REE in CFS. We also studied the myocardial perfusion in CFS by thallium201 SPECT scans to compare the results with Syndrome X.

Methods:   All patients who fulfilled the modified CDC criteria for CFS were included in our studies. For investigations that required the administration of radiopharmaceuticals (e.g. cardiac-thallium201 SPECT scans), patients between the age of 18 - 65 years were recruited after informed consent. A comparable group of healthy, sedentary volunteers were tested as controls in the REE study.

Results:  Fatigue was fluctuant in most patients with CFS. This was induced or worsened by physical activities (exercise), mental stress and chemicals that affect  ion channel function (e.g. alcohol, quinine and anaesthetics). Significant perfusion defects were observed in the cardiac-thallium201 SPECT scans in 70% of CFS patients, similar to that described in patients with syndrome X. In a separate study, a significant number of CFS patients were found to have elevated REE as compared to the controls using total body potassium (TBK) as the refererence (REE TBK).4

Conclusion:  Abnormal thallium201-cardiac SPECT scans in CFS similar to those described in syndrome X suggest a common mechanism for both these conditions. An abnormality of membrane ion channel function is considered the underlying mechanism in syndrome X. Increased REETBK; in a subgroup of CFS patients suggests that some CFS patients spend more energy in maintaining essential body function at the expense of the energy available for other physical activities. Since 30% of REE is expended to maintain physiological ion gradients in normal health, cell membranes that leak ions increase REETBK  Elevated REE and abnormal cardiac perfusion scans in CFS provide the first objective and indirect support to our hypothesis that symptoms in CFS could be the result of an acquired abnormality of the voltage or ligand-gated ion channels. It is possible that such alteration of transmembrane ion traffic could affect normal receptor sensitivity to neurochemicals and neurohormones such as acetylcholine, serotonin or other monoamines, accounting for the neuroendocrine abnormalities previously documented in CFS.