definition: severe, debilitating fatigue, lasting at least six months of new and definite onset associated with at least 4 of the following symptoms: impaired memory or concentration, sore throat, adenopathy, myalgias, arthralgias, new headaches, unrefreshing sleep, and post-exertion malaise. Additionally, a group of medical and psychiatric conditions that can produce fatigue must be ruled out.
etiology:
When the syndrome was first being discussed, the Epstein-Barr virus was thought to be the sole infectious agent. This was because:
a high percentage of patients had a history of mononucleosis
EBV is in a family of viruses that may create lifelong latent
infection in the host after recovery from the acute infection
signs and symptoms of CFS are similar to that of mononucleosis
However, it has proven difficult to achieve consistent results among patients. Identification of a single etiologic agent has also proven problematic. Antibody testing for the various EBV factors has proven inconclusive. Currently, human herpes virus 6 is under investigation as a causal agent.
Other viruses have been implicated in the disease, notably cytomegalovirus (CMV), which produces a disease similar to mononucleosis that usually strikes older people, and toxoplasmosis, a parasitic disease carried by cats. Recent work by a number of investigators has revealed a complex of physiologic disturbances including sleep disorders, adrenal, and hypothalamic dysfunction. Central nervous system involvement has also been postulated with some supporting studies. As a result, a number of new terms are being used to describe the syndrome, including chronic fatigue immune disorder (CFID). At least one investigator (Teitelbaum), has linked chronic fatigue and fibromyalgia.
Reports of a prolonged and recurrent mononucleosis-like disease surfaced in the 1940s and 1950s, yet it is still far from being a clearly studied or accepted syndrome.
It is suggested that CFS patients may have poor glycogen storage, candida with dysbiosis, hypersensitivities and a history of hepatitis or mononucleosis. (Easley) Recent investigators have suggested that a number of these may coexist and require simultaneous treatment.
signs and symptoms
Fatigue: by definition intense, individuals may be able to perform in a limited fashion at work or home, but easily fatigue from it. It may cause patients to give up their jobs, and greatly curtail other activities. Sometimes they may be bedridden, and slight activities such as housecleaning or going for a walk may necessitate a recovery period of 2-3 days. Usually more strenuous exertion and exercising are impossible. Occasionally, patients have alternating periods of fatigue and normalcy. The disease may begin gradually, with the fatigue slowly growing until it becomes overwhelming. It may also follow viral infections like influenza and gastroenteritis, appearing with sudden onset. Some patients seem to enter the fatigue with preexisting fibromyalgia. Establishing specifics of onset and duration is important.
Recurrent pharyngitis
HEENT lymphadenopathy
Recurrent headaches
Chronic low-grade fever
Myalgia and/or peri-arthralgia
Inability to concentrate
Gastrointestinal upset
Emotional upset and/or depression
The patient may have a history of allergies, difficulty sleeping, weight loss or gain
lab findings:
Laboratory investigation is directed at eliminating organic causes of fatigue. A basic approach includes general health panel blood testing (includes complete blood cell count with differential, serum urea nitrogen, creatinine, electrolytes, glucose, calcium, phosphorus, thyroid stimulating hormone, alanine aminotransferase, alkaline phosphatase, total protein, albumin, and globulin levels), erythrocyte sedimentation rate and urinalysis.
Many physicians have found value in determining the factors contributing to this condition by testing DHEAS levels and through the Adrenal Stress Index.
Other optional tests include antinuclear antibodies, serum cortisol (free), rheumatoid factor (quantitative), immunoglobulin levels, tuberculin skin testing, Lyme serology, and HIV testing.
Some practitioners have concluded that Ebstein-Barr viral titers have proven of little value in diagnosis or treatment; others find that the titers correspondent to the severity of the condition in some patients and that changes in a patient's symptoms may correspond to changes in the titers.
course and prognosis
This disorder is not well recognized by most conventional physicians, despite empirical evidence and clinical research. Conventional treatment involves suppression and/or palliation of symptoms, e.g. salicylates for fever, headaches, and myalgia. With no further diagnosis or treatment, the patient is likely to have bouts of remissions and exacerbations that may develop into a constant, persistent disease.
Appropriate diagnosis and treatment lead to excellent recovery rates in most sufferers who comply. Very few cases are refractory to treatment.
differential diagnosis
The following must be eliminated as potential causes of the patients fatigue:
Hypothyroidism
Primary or secondary immunodeficiency conditions
Hodgkins and Non-Hodgkins lymphoma
SLE
AIDS
Burkitts lymphoma or nasopharyngeal carcinoma
Chronic renal failure or renal transplant
Rheumatoid arthritis, ankylosing spondylitis
Multiple sclerosis
Cancer chemotherapy
Nonlymphomatous cancerous tumors
Unrecognized or improperly treated depression
footnotes