Chronic Fatigue Syndrome (CFS)

The cause of CFS is unknown, although there are many theories of causative factors, including chronic viral infections, central nervous system (brain) abnormalities, immune system abnormalities, environmental toxic exposures and psychological stress. Some experts believe chronic fatigue syndrome might be triggered by a combination of factors in people who have a predisposition for the disorder.

CFS manifests in the following signs and symptoms which are used to diagnose this condition:

• Fatigue
• Loss of memory or concentration
• Sore throat
• Enlarged lymph nodes in your neck or armpits
• Unexplained muscle pain
• Pain that moves from one joint to another without swelling or redness
• Headache of a new type, pattern or severity
• Unrefreshing sleep
• Extreme exhaustion lasting more than 24 hours after physical or mental exercise

Some of the potential causative factors that have been studied include:

• Central nervous system problems.  Several symptoms reported by CFS patients—including fatigue; impaired concentration, attention, and memory; and headache—suggest that the central nervous system may be involved in the pathophysiology of the syndrome. Researchers have investigated a central nervous system (CNS) link to CFS but have been unable to identify a causal link.
• Chronic pathogenic infections. Some people develop CFS after suffering from a viral, bacterial or other pathogenic infection. Therefore, some researchers believe that certain viruses or other pathogens might trigger the disorder. Suspicious viruses include Epstein-Barr virus (EBV), human herpes virus 6 (HHV-6) and other viruses. Some bacterial species that can become chronic and have been associated with fatigue and other symptoms are Borrelia, Bartonella and Babesia.
• Toxicity and compromised hepatic detoxification. Some research suggests that toxic exposures to environmental chemicals and heavy metals may play a role in the development of CFS.  Studies suggest an association with increased levels of heavy metals and other toxins in patients with CFS and improvement in symptoms when the elimination of these toxins is supported via hepatic detoxification pathways.
• Mitochondrial dysfunction.  The mitochondria are the “power-houses” of the cells which provide the energy needed to fuel cellular processes and efficient ATP production is required for tissue and organ health.  However, the mitochondria are very vulnerable to oxidative stress which can impair mitochondrial production of ATP.  Impaired ATP production by the mitochondria has been associated with CFS and is believed to be due to excessive oxidative stress and insufficient antioxidant enzyme activity.
• Immune system dysfunction. The immune system of people with CFS appears to be dysfunctional.  There is often chronic inflammation as a result of other problems such as chronic infections, compromised hepatic detoxification, oxidative stress and mitochondrial dysfunction.
• Hormonal imbalances. Hormonal imbalances are common in people with CFS, particularly with the hypothalamic-pituitary-adrenal (H-P-A) axis.  The adrenal glands are responsible for producing corticosteroids, such as cortisol, which are important in regulating immune responses, glucose levels and the sleep-wake cycle, among other functions.

There is no single test to confirm a diagnosis of CFS. You may need a variety of medical tests to rule out other health problems that have similar symptoms.