A RENEWED focus on improving the diagnosis and management of patients with chronic fatigue has been welcomed, but an Australian expert says there is a long way to go before this complex illness is well understood.
Dr Robert Loblay, director of the Royal Prince Alfred Hospital Allergy Unit in Sydney, said the new focus in the US drew attention to the many unanswered questions regarding myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), but it did not offer a significant advance on the current knowledge base.
Dr Loblay said it was disappointing, but not surprising, that little progress had been made in the area of ME/CFS since he co-convened a working group to develop CFS clinical guidelines published in 2002. (1)
His comments follow the publication in the Annals of Internal Medicine
of reviews of treatment and of diagnostic methods for ME/CFS as well as a position paper. (2)
The position paper called for renewed research efforts and proposed a new case definition and a new name for the illness — systemic exertion intolerance disease.
Dr Loblay said the call for a new case definition was “misguided”.
“The purpose of having an agreed case definition is so [research] results can be compared between different studies”, he said. “What they are not really grasping is that there is no clear dividing line between people who get lesser degrees of those symptoms and those who have more severe degrees which leave them in a much more debilitated and disabled state. It’s a spectrum.”
An editorial accompanying the US reviews stated that a key message in the papers was that ME/CFS was a “real illness”. (3)
“When skeptical physicians … tell patients with ME/CFS that ‘there is nothing wrong,’ they not only commit a diagnostic error: They also compound the patients’ suffering.”
Dr Loblay said the papers highlighted continued sceptisim around this illness in the US, but said in his experience such resistance to this diagnosis was no longer common in Australia.
“Subjectively, I do think attitudes have changed. Certainly among the younger doctors, there is much more willingness to accept that people with this condition are genuinely ill. Even though we don’t understand what’s causing [their illness], these patients deserve a careful evaluation and whatever treatment modalities might seem appropriate for the individual”, he said.
Professor Donald Staines, co-director of Griffith University’s National Centre for Neuroimmunology and Emerging Diseases (NCNED), said the Annals of Internal Medicine editorial was “right on the money”.
“It alludes to the fact that some medical practitioners are cautious about the diagnosis — some are even sceptical — because no laboratory test to diagnose this illness has been developed”, he said.
However, Professor Staines, who runs a specialised ME/CFS clinic at the university, said he recognised the “extraordinary difficulty” in diagnosing this illness.
“I really empathise with GPs because there is an extraordinary range of reasonably common clinical conditions that also produce debilitating fatigue. For example, people with thyroid disease, diabetes and other autoimmune diseases”, he said.
“By the time we get to see patients [in the clinic] they have been very thoroughly investigated for other things and that’s the way it should be, because until we get a sensitive and specific test, it is a diagnosis of exclusion.”
He said an international case definition had helped define the symptom presentation of the illness. (4)
Professor Staines and colleagues recently published research identifying genetic variances in patients with ME/CFS that might hold the key to understanding the pathology of this illness. (5)
He said the identification of single nucleotide polymorphisms (SNPs) both in transient receptor potential ion channels and acetylcholine receptors in patients with ME/CFS provided some clues to the biological basis of the condition.
The presence of SNPs in the genes of these two important receptors could lead to heightened sensitivity to physical and chemical threats and impaired nervous system functioning.
Professor Staines said if the nature of the receptor was changed, it could not do its job and create impairment. “That’s what we think is going on with ME/CFS.”
Investigations were continuing at NCNED, he said.
Dr Loblay said the NCNED findings were intriguing and represented a small step forward.
However, he said it was likely epigenetics also played a role in the development of ME/CFS and only through the study of difficult-to-access brain and nervous system tissue would this mechanism be fully understood.
(Photo: Squaredpixels / iStock)