AHMF: 1999 Chaudhuri Abstract

The Neurological Mechanism of CFS

Abhijit Chaudhuri, DM, MD, MB, BS, MRCP (UK)

Clinical Lecturer, Dept of Neurology,
University of Glasgow and Dept of Neurology,
Institute of Neurological Sciences,
Southern General Hospital,
Glasgow, G51 4TF
Tel: +61 44 141 201 2489/2509
Fax: +61 44 141 201 2515/2993.

Chronic Fatigue Syndrome (CFS) is a common disorder that is characterised by fluctuating symptoms of fatigue, confusion, anomia, impaired concentration and musculoskeletal symptoms. Additional common symptoms include migraine-like headache, paroxysmal chest pain and hemisensory symptoms. Many of these symptoms including the severity of fatigue may be periodic, fluctuant and induced by physical and mental activities, stress and drugs or toxins. The fatigue in CFS is very similar to that found in disorders of the central nervous system such as Parkinson's disease (PD), Alzheimer's disease, multiple system atrophy and multiple sclerosis (MS).

Although fatigue is common in depression, CFS patients differ from patients with major depression in their clinical profile, steroid metabolism and response to standard antidepressant drug therapy. Current evidence strongly suggests that abnormal central neurotransmitter balance affecting monoamine metabolism, particularly dopamine, may play an important role in fatigue mechanism. In addition, changes in the neuronal ion channel function from time to time offers a rational basis to explain fluctuating fatigue and related symptoms in CFS. Ion channel abnormality leading to selective neuronal instability and altered neurochemical sensitivity may be the fundamental disease mechanism in CFS similar to other paroxysmal disorders affecting brain function such as migraine and epilepsy.