Assessment of a retrovirus sequence and other possible risk factors for the chronic fatigue syndrome in adults

Abstract:

OBJECTIVE: To assess whether the human T-lymphotropic virus type II (HTLV-II) gag gene sequence, a purportedly new laboratory marker of the chronic fatigue syndrome (CFS), and other possible risk factors for CFS, particularly those associated with retroviral transmission, are associated with well-characterized CFS.

DESIGN: Two matched case-control studies.

SETTING: The metropolitan Atlanta area.

PATIENTS: Twenty-one patients with CFS who were identified by the Centers for Disease Control and Prevention CFS surveillance system; 21 CDC employee controls (laboratory study) and 42 neighborhood controls (risk-factor study) who were matched to patients by age, race, and gender.

MEASUREMENTS: Peripheral blood lymphocytes and leukocytes were assayed for the HTLV-II gag gene sequence by polymerase chain reaction and specific Southern blot hybridization. Questionnaires elicited demographic and clinical information and a history of exposures associated with retrovirus transmission (for example, blood transfusions, sexual practices, intravenous drug use).

RESULTS: All patients were white and 86% were female. The median age at illness onset was 34 years (range, 16 to 51 years). The HTLV-II gag gene sequence was not identified in the blood of any patient or control under conditions in which the appropriate assay controls were positive. No statistical differences were observed between patients and controls in frequency of blood transfusions (10% compared with 7%), median number of sex partners before illness (3 compared with 3), bisexual or homosexual behavior (14% compared with 7%), intravenous drug use (0% compared with 0%), and other factors associated with retroviral infection.

CONCLUSIONS: The HTLV-II gag gene sequence was not a marker for CFS in this small study of well-defined patients, nor did other characteristics of the patients and controls support the hypothesis that a retrovirus, transmitted by usual modes, was a cause of CFS.

 

Source: Khan AS, Heneine WM, Chapman LE, Gary HE Jr, Woods TC, Folks TM, Schonberger LB. Assessment of a retrovirus sequence and other possible risk factors for the chronic fatigue syndrome in adults. Ann Intern Med. 1993 Feb 15;118(4):241-5. http://www.ncbi.nlm.nih.gov/pubmed/8420441

 

NIH conference. Chronic fatigue syndrome research. Definition and medical outcome assessment

Abstract:

A workshop was held 18 to 19 March 1991 at the National Institutes of Health to address critical issues in research concerning the chronic fatigue syndrome (CFS). Case definition, confounding diagnoses, and medical outcome assessment by laboratory and other means were considered from the perspectives of key medical specialties involved in CFS research.

It was recommended that published Centers for Disease Control (CDC) case-definition criteria be modified to exclude fewer patients from analysis because of a history of psychiatric disorder. Specific recommendations were made concerning the inclusion or exclusion of other major confounding diagnoses, and a standard panel of laboratory tests was specified for initial patient evaluation.

The workshop emphasized the importance of recognizing other conditions that could explain the patient’s symptoms and that may be treatable. It was viewed as essential for the investigator to screen for psychiatric disorder using a combination of self-report instruments followed by at least one structured interview to identify patients who should be excluded from studies or considered as a separate subgroup in data analysis.

Because CFS is not a homogeneous abnormality and because there is no single pathogenic mechanism, research progress may depend upon delineation of these and other patient subgroups for separate data analysis. Despite preliminary data, no physical finding or laboratory test was deemed confirmatory of the diagnosis of CFS.

For assessment of clinical status, investigators must rely on the use of standardized instruments for patient self-reporting of fatigue, mood disturbance, functional status, sleep disorder, global well-being, and pain. Further research is needed to develop better instruments for quantifying these domains in patients with CFS.

 

Source: Schluederberg A, Straus SE, Peterson P, Blumenthal S, Komaroff AL, Spring SB, Landay A, Buchwald D. NIH conference. Chronic fatigue syndrome research. Definition and medical outcome assessment. Ann Intern Med. 1992 Aug 15;117(4):325-31. http://www.ncbi.nlm.nih.gov/pubmed/1322076