- Viral Infections: Some patients develop CFS after having a viral infection. Some researchers believe that the disease is triggered by certain viruses, including Epstein-Barr, human herpes virus 6 and mouse leukemia viruses. To date, no definitive link has been found.
- Immune System Problems: The immune systems in CFS patients appear to be at least slightly compromised. Unfortunately, it has been difficult to determine whether the immune impairment is a cause of the disease or a result of it. It remains unclear if this impairment is significant in most sufferers to actually contribute to its onset.
- Hormonal Imbalances: Patients with CFS sometimes experience abnormal blood levels of hormones produced by the hypothalamus, pituitary glands or adrenal glands.
Chronic Fatigue Syndrome: The Symptoms
Because of a lack of objective findings in patients and a continually evolving understanding of the disease, diagnostic criteria may not be consistent. Typically, CFS is diagnosed when a patient exhibits:
● Clinically evaluated, unexplained, persistent or relapsing fatigue that is of new or definite onset, is not the result of ongoing exertion, is not alleviated by rest, and results in a significant reduction in previous levels of occupational, educational, social or personal activities
● Four or more of the following symptoms that persist or recur during six or more consecutive months, and which did not predate the onset of fatigue:
◦ Self-reported impairment in short-term memory or concentration
◦ Sore throat