title: RNase L levels in peripheral blood mononuclear cells: 37-kilodalton/83-kilodalton isoform ratio is a potential test for chronic fatigue syndrome.
abstract: Chronic fatigue syndrome (CFS) is a disorder characterized by debilitating fatigue associated with immunological abnormalities. The etiology remains unclear. A low-molecular-mass (37 kDa) isoform of RNase L has been described in peripheral blood mononuclear cell (PBMC) extracts, and the ratio of two isoforms of RNase L (37 kDa/83 kDa) has been proposed as a potential biochemical marker of CFS. In a prospective case-control study, we tested whether the RNase L 37-kDa/83-kDa ratio could discriminate a SFC population. We compared the ratio of RNase L isoforms in PBMCs from 11 patients with CFS (6 women and 5 men; mean age +/- standard deviation, 43.2 +/- 13.8 years) and PBMCs from 14 healthy well-matched volunteers (10 women and 4 men; age, 39.1 +/- 11.6 years). A ratio of RNase L of 0.4 used as a threshold allowed diagnosis of CFS with high sensitivity (91%; 95% confidence interval [CI], 57 to 99%) and specificity (71%; 95% CI, 41 to 90%). The positive and negative prognostic values were 71% (95% CI, 41 to 90%) and 91% (95% CI, 57 to 99%), respectively. In the absence of acute infection or chronic inflammation, a high RNase L ratio could distinguish CFS patients from healthy volunteers. Additional large studies and follow-up studies are required to confirm the stability of this high ratio of RNase L isoforms in a CFS group.
authors.affiliation: Service de Médecine Interne, Hôpital Saint Antoine, 75571 Paris Cedex 12, France. kiet.tiev@sat.ap-hop-paris.fr
authors.forename: Kiet Phong
authors.initials: KP
authors.lastname: Tiev
authors.forename: Edith
authors.initials: E
authors.lastname: Demettre
authors.forename: Philippe
authors.initials: P
authors.lastname: Ercolano
authors.forename: Lionel
authors.initials: L
authors.lastname: Bastide
authors.forename: Bernard
authors.initials: B
authors.lastname: Lebleu
authors.forename: Jean
authors.initials: J
authors.lastname: Cabane
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004722:Endoribonucleases / Q000032:analysis* / Q000737:chemistry; D015673:Fatigue Syndrome, Chronic / Q000175:diagnosis* / Q000276:immunology; D005260:Female; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D008970:Molecular Weight; D011446:Prospective Studies; D012680:Sensitivity and Specificity
chemical_list: D004722:Endoribonucleases; C031956:2-5A-dependent ribonuclease