Chronic fatigue syndrome

Chronic Fatigue Syndrome

What Is Chronic Fatigue Syndrome?

Chronic fatigue syndrome (CFS) is a debilitating disorder characterized by extreme fatigue or tiredness that doesn’t go away with rest, and can’t be explained by an underlying medical condition. CFS can also be referred to as myalgic encephalomyelitis (ME) or systemic exertion intolerance disease (SEID). The causes of CFS aren’t well-understood. Some theories include viral infection, psychological stress, or a combination of factors. Because no single cause has been identified, and because many other illnesses produce similar symptoms, CFS can be difficult to diagnose. There are no tests for CFS, so your doctor will have to rule out other causes for your fatigue. While CFS has been a controversial diagnosis in the past, it’s now widely accepted as a real medical condition. CFS can affect anyone, though it’s most common among women in their 40s and 50s. There is no current cure, so treatment for CFS focuses on relieving your symptoms.

What Causes CFS?

The cause of CFS is unknown. Researchers speculate that viruses, hypotension (unusually low blood pressure), a weakened immune system, and hormonal imbalances could all be contributing factors. It’s also possible that some people are genetically predisposed to develop CFS. Though CFS can sometimes develop after a viral infection, no single type of infection has been found to cause CFS. Some viruses that have been studied in relation to CFS include Epstein-Barr virus (EBV), human herpesvirus 6, Ross River virus (RRV), rubella, Coxiella burnetti, and mycoplasma. Researchers have found that a person who has been infected with at least three of the implicated pathogens has a greater chance of developing CFS. The U.S. Centers for Disease Control and Prevention (CDC) have suggested that CFS may be the end stage of multiple different conditions, rather than one unique condition. In fact, 10 to 12 percent of people with Epstein-Barr virus, Ross River virus, and Coxiella burnetti develop a condition that meets the criteria for a CFS diagnosis. People with CFS sometimes have weakened immune systems, but doctors don’t know whether this is enough to cause the disease. Additionally, people with CFS sometimes have abnormal hormone levels, but doctors haven’t yet concluded whether this is significant.

What Are the Symptoms of CFS?

The symptoms of CFS vary from person to person and based on the severity of the condition. The most common symptom is fatigue that is severe enough to interfere with your daily activities. For CFS to be diagnosed, fatigue must last for at least six months and must not be curable with bed rest, and you must have at least four other symptoms as well.

Other symptoms of CFS may include:

  • loss of memory or concentration
  • feeling unrefreshed after a night’s sleep
  • chronic insomnia (and other sleep disorders)
  • muscle pain
  • frequent headaches
  • multijoint pain without redness or swelling
  • frequent sore throat
  • tender lymph nodes in your neck and armpits

You may also experience illness or extreme fatigue after physical or mental activities. This can last for more than 24 hours after the activity. People are sometimes affected by CFS in cycles, with periods of feeling worse and then better again. Symptoms may sometimes even disappear completely (remission). However, it’s still possible for them to come back again later (relapse). The cycle of remission and relapse can make it difficult to manage your symptoms.

How Is CFS Diagnosed?

CFS is a very challenging condition to diagnose. According to the CDC, only 20 percent of the estimated 1 to 3 million Americans with CFS have been diagnosed. There are no lab tests to screen for CFS and its symptoms are common to many illnesses. Many people with CFS don’t look obviously sick, so doctors may not recognize that they are ill. In order to be diagnosed with CFS, you must have at least four of the above symptoms listed. You also must have severe, unexplained fatigue that cannot be cured with bed rest. The fatigue and other symptoms must last for six months or longer.

Ruling out other potential causes of your fatigue is a key part of the diagnosis process. Some conditions whose symptoms resemble those of CFS include:

  • mononucleosis
  • Lyme disease
  • multiple sclerosis
  • lupus (SLE)
  • hypothyroidism
  • fibromyalgia
  • major depressive disorder

You may also experience symptoms of CFS if you are severely obese or have depressive disorders or sleep disorders. The side effects of certain drugs, such as antihistamines and alcohol, can mimic CFS as well. Because the symptoms of CFS resemble those of other conditions, it’s important not to self-diagnose and to talk to your doctor.