Chronic Fatigue Syndrome and Disorders...
Chronic Fatigue Syndrome is not one condition or disorder. It is usually a combination of many disorders. The word "syndrome" in medical context is often used to describe groups symptoms when the cause is generally unknown and for which there is no specific treatment. It's a "catch-all" term for those who experience chronic fatigue and have no known singular medical diagnosis to explain why.
As an example, a woman may go to her Doctor and complain of overwhelming fatigue. Blood tests will be done to check for thyroid function, iron levels in the blood, vitamin B12 deficiency, inflammation, infections, and other medical parameters. All of these tests come back normal, yet she is still complaining of fatigue. This is a classic example of medically diagnosed "chronic fatigue syndrome". Since there is no obvious condition or objective clinical tests indicating a pathology, then it must just be "chronic fatigue". This is an extremely frustrating diagnosis for someone to receive.
Chronic Fatigue Syndrome isn't ONE condition, it's a compounded effect of several conditions in most who suffer with it. And for many people, the conditions leading to their chronic fatigue is completely different than those conditions in other sufferers of the "condition"
If we consider all the clinical (apparent on clinical testing) and sub-clinical (not apparent on clinical testing) conditions which can cause FATIGUE in people, it becomes very obvious why it is poorly diagnosed and poorly treated.
There are literally hundreds of clinical and sub clinical medical conditions which can cause fatigue in patients. There are literally hundreds of other dietary, environmental, behavioral and physiological conditions which can also cause fatigue.
Everyone who suffers with "chronic fatigue syndrome " is likely to a completely unique set of factors associated with their overall fatigue symptom picture. It's easy to see how it is impossible to come up with one distinct set of diagnostic criteria those suffering with the condition. And it's even less likely to be able to come up with one medical treatment to address and fix the "condition" in those who suffer with it.
Chronic Fatigue Syndrome cannot successfully be treated as "One" condition. It has to be assessed and treated by considering all the potential factors and triggers a patient may have contributing to their fatigue state.