M. Nishikai et al., Autoantibodies to a 68/48 kDa protein in chronic fatigue syndrome and primary fibromyalgia: a possible marker for hypersomnia and cognitive disorders, RHEUMATOLOG, 40(7), 2001, pp. 806-810
Objective. To identify antinuclear antibodies (ANA) specific for chronic fa
tigue syndrome (CFS), and in related conditions such as fibromyalgia (FM) o
r psychiatric disorders.
Methods. One hundred and fourteen CFS patients and 125 primary and secondar
y FM patients were selected based on criteria advocated by the Centers for
Disease Control and Prevention and by the American College of Rheumatology,
respectively. As controls, healthy subjects and patients with either vario
us psychiatric disorders or diffuse connective tissue diseases were include
d. Autoantibodies were examined by immunoblot utilizing HeLa cell extracts
as the antigen.
Results. Autoantibodies to a 68/48 kDa protein were present in 13.2 and 15.
6% of patients with CFS and primary FM, respectively. In addition, autoanti
bodies to a 45 kDa protein were found in 37.1 and 21.6% of the patients wit
h secondary FM and psychiatric disorders, respectively. Meanwhile, these tw
o autoantibodies were not found at all in connective tissue disease patient
s without FM, nor in healthy subjects (P < 0.05). As a group, the anti-68/4
8 kDa-positive CFS patients presented more frequently with hypersomnia (P <
0.005), short-term amnesia (P < 0.07) or difficulty in concentration (P <
0.05) than those CFS patients without the antibodies.
Conclusions. The presence of the anti-68/48 kDa protein antibodies in a por
tion or both CFS and primary FM patients suggests the existence of a common
immunological background. These antibodies may find utility as possible ma
rkers for a clinicoserological subset of CFS, FM patients with hypersomnia
and cognitive complaints.