Fatigue Often Mislabeled Epstein-Barr, Studies Say
The Epstein-Barr virus is often blamed for causing a chronic fatigue syndrome that bears its name. But according to two studies being published today in the Journal of the American Medical Assn., the virus appears to have nothing to do with the disorder in many cases.
The studies, however, are likely to frustrate both patients and physicians. While they confirm the existence of the ailment, they shed little light on its actual cause or how to treat it. The Epstein-Barr virus may cause some cases, but the cause of most cases remains unknown, the studies said.
Because fatigue is such a common human affliction, it is often difficult for patients and physicians to determine whether this is a symptom of a serious illness. In recent years, many people have blamed the Epstein-Barr virus for this malaise.
In one of the new studies, Centers for Disease Control researchers studied 15 patients from the Lake Tahoe area diagnosed as having the chronic fatigue syndrome; their symptoms included disabling fatigue, fever, sore throat and swollen lymph nodes.
But the researchers could not find a definite relationship between the fatigue syndrome and exposure to the virus. They found that blood tests for the Epstein-Barr virus could not “reliably differentiate” the 15 seriously ill patients from other fatigue patients with less severe illnesses and healthy people.
The patients in the study were some of the estimated 180 Lake Tahoe residents whose plight attracted national attention after they developed the mysterious chronic fatigue illness in 1985 and 1986.
In the second study, Harvard Medical School researchers found that 21% of 500 adults consulting physicians in Massachusetts for a wide variety of problems complained of severe fatigue and related symptoms, including sore throats, muscle aches and headaches. But in this group of patients as well, the researchers could not find a definite relationship between the fatigue syndrome and exposure to the virus.
“Things are still not clear,” said Dr. Anthony L. Komaroff of Boston’s Brigham and Women’s Hospital, one of the Harvard researchers.
Komaroff added: “I have no doubt that there is a (chronic fatigue) illness which is very real . . . and may be growing in frequency. But I do not know what the cause is. I think the Epstein-Barr virus is the cause of some cases, but not most.”
The fatigue syndrome is sometimes called “chronic mononucleosis” or “chronic active Epstein-Barr virus infection.” The Epstein-Barr virus is best known as the cause of acute mononucleosis, the so-called “kissing disease.” Acute mononucleosis affects primarily children and young adults, but its short-lived symptoms are similar to those experienced by the chronic fatigue patients.
Diagnosis of chronic Epstein-Barr virus infection is complicated because by the age of 60, four-fifths of Americans will have been exposed to the virus, often through contaminated eating and drinking utensils. These infected individuals become lifelong carriers of the virus, although the vast majority either never had symptoms to begin with or recovered completely.
Over a period of months to years, many of the chronic fatigue patients appear to recover; others have waxing and waning symptoms or become progressively disabled. Some develop immune system abnormalities and difficulties with memory and concentration.
Despite the scientific uncertainty about the fatigue syndrome, leading Epstein-Barr researchers are deluged with hundreds of phone calls and letters from patients who think they have the disease and from their physicians, said Dr. Stephen E. Straus of the National Institutes of Allergy and Infectious Diseases, who wrote an editorial for the medical journal about the illness.
Expensive Antiviral Medicine
Thousands of these patients have joined local and national organizations designed to help them cope with the syndrome. “The people (who feel they have this) are aggressive, tenacious and desperate,” Straus said in an interview. “They have not been satisfied by traditional health care in the past. They seek out anything which gives them promise.”
The frustration has also led some physicians to hospitalize chronic fatigue patients and to treat them with intravenous doses of the expensive antiviral medicine, acyclovir, despite a lack of evidence that the drug is beneficial, according to Straus and Komaroff. The medication can cause serious side effects such as kidney damage.
In a recently completed National Institutes of Health study of 27 patients with the syndrome, Straus found that acyclovir was no more effective than a placebo medicine, according to the April issue of Clinical Research, a medical journal. The full results of the study will be presented at the American Society for Clinical Investigation meeting Monday in San Diego.
In addition to the Epstein-Barr virus, one widely discussed speculation is that a newly described human herpes virus, called Human B-lymphotrophic virus, may be associated with chronic fatigue states. But so far no data to support this suggestion has been reported, according to Straus’ editorial.
“We do not have data to support (such) conclusions,” said Dr. Howard Z. Streicher of the National Cancer Institute in Bethesda, Md., who is investigating whether the new virus causes human disease.
