No blood test or imaging scan can diagnose chronic fatigue syndrome (CFS). The only way doctors can tell is by ruling out other illnesses that can cause CFS-like symptoms. If none are found, or if chronic fatigue persists after an underlying problem is treated successfully, then CFS may be diagnosed.
Criteria
According to the Centers for Disease Control and Prevention (CDC), a diagnosis of CFS should be made according to the following criteria:
- The patient has been evaluated by a health care provider and has unexplained persistent or relapsing chronic fatigue that is of new or definite onset (e.g., not lifelong).
- The chronic fatigue is not caused by ongoing exertion, rest does not help the person feel better and the fatigue severely interferes with quality of life.
Symptoms
In addition to chronic fatigue, the patient also suffers from four or more of the following symptoms:
- Substantial impairment of short-term memory or concentration
- Sore throat
- Tender lymph nodes
- Muscle pain
- Multi-joint pain without swelling or redness
- Headaches of a new type, pattern or severity
- Unrefreshing sleep
- Post-exertion malaise lasting more than 24 hours
These symptoms must have persisted or recurred during six or more consecutive months of illness and must not have predated the fatigue.
Unofficial symptoms
According to the Chronic Fatigue and Immune Dysfunction Syndrome (CFIDS) Association of America, a patient support and educational organization, there are other "unofficial" symptoms reported by some CFS patients:
- Cognitive problems (such as word-finding difficulties; inability to comprehend and/or retain what is read; inability to calculate numbers; and impairment of speech and/or reasoning)
- Visual disturbances (blurring, sensitivity to light, eye pain, need for frequent prescription changes)
- Psychological problems (depression, irritability, anxiety, panic attacks, personality changes, mood swings)
- Chills and night sweats
- Shortness of breath
- Dizziness and balance problems
- Sensitivity to heat and/or cold
- Alcohol intolerance
- Irritable bowel (abdominal pain, diarrhea, constipation)
- Low-grade fever or low body temperature
- Numbness, tingling and/or burning sensations in the face or extremities
- Dryness of the mouth and eyes
- Ringing in the ears (tinnitus)
- Sensitivities to noise/sound, odors, chemicals and medications
- Light-headedness
- Fainting
- Muscle twitching
What happens during your medical exam?
The National Institute for Allergy and Infectious Diseases (NIAID) recommends doctors take the following steps to investigate a possible diagnosis of CFS:
Complete medical history. You'll be asked about past illnesses, surgeries, accidents or other physical or psychological traumas, or psychiatric disorders. Also, inform your doctor of any medically unexplained symptoms you've had recently. The doctor needs to know if you use drugs and drink too much alcohol. Also, you need to list your prescription or nonprescription medications and food supplements. Knowing your psychological and social circumstances around the time that your CFS symptoms began also may help the doctor diagnose you.
Mental status exam. This exam is designed to identify abnormalities in mood, intellectual function, memory and personality. Be frank about any symptoms of depression or anxiety and self-destructive thoughts you may be having.
Thorough physical examination. Your doctor listens to your heart and lungs, tests your reflexes, looks into your throat, palpitates your throat area for signs of thyroid or lymph node enlargement and, perhaps, does an electrocardiogram.
Minimum battery of laboratory screening tests. You are asked to provide a urine specimen for a standard urinalysis, and some blood for the following tests: a complete blood count with leukocyte differential, chemistry panel, thyroid function test, erythrocyte sedimentation rate, liver tests like alanine aminotransferase, total protein, albumin, globulin, and alkaline phosphatase, and other chemistry tests such as calcium, phosphorous and glucose.
If you are diagnosed with CFS, your doctor may wish to schedule follow-up visits every six months or so until your symptoms stabilize or go away. Notify your doctor if your symptoms change or worsen or if new symptoms arise.
