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found in CFS
with chronic fatigue
syndrome (CFS) are 3.5 times more likely to have joint hypermobility compared to
non-fatigued, age-and gender-matched controls, Johns Hopkins University
researchers report. More of the adolescents with CFS could bend their fingers or
thumbs backward, hyperextend their knees and elbows, place their legs behind
their heads and place their palms flat on the floor without bending their knees
— all signs of joint hypermobility.
This study contradicts the belief that CFS patients
normal physical examinations. Since approximately 20 percent of healthy
adolescents have hypermobility, this is not a diagnostic test for CFS, but it
may lead a clinician to suspect CFS if a patient has other symptoms.
The reason for hypermobility is unclear, but the
researchers offer several possibilities. First, it
may reflect connective tissue hyperextensibility, which could explain the
increased venous pooling and orthostatic intolerance seen in adolescents with
CFS. Second, it may lead to decreased physical activity and an increased risk
for CFS. Third, there may be another factor that is associated with both
hypermobility and CFS, paralleling a recent finding that a particular
chromosomal phenotype is associated both with joint hypermobility and panic and
phobic disorders. The authors remind readers that panic and anxiety disorders
are not universally seen in CFS.
Barron DF et al. Joint hypermobility is more common
children with chronic fatigue syndrome than in healthy controls. J
Unique RNase L generated by normal
years ago, researchers first
published the finding that some people with CFS have an unusual form of RNase L,
a key component of the antiviral defense system. Further studies have shown that
this unique RNase L protein is smaller and more active than normal 83 kilodalton
(kDa) RNase L. But, until now they have not known whether this low molecular
weight RNase-L is a new protein or is processed from the normal RNase
European scientists now report they have discovered
the 30 and 37 kDa weight forms of RNase L in CFS are generated by breakdown of
normal RNase L into two main fragments. In the laboratory, they found that
peripheral blood mononuclear cell extracts from CFS patients cleaved normal 83
kDa RNase L into the two end sections of the RNase L protein and removed the 16
kDa middle section. They then duplicated this phenomenon using human leukocyte
elastase (HLE), an enzyme known to break down proteins.
This knowledge takes researchers a step further toward
understanding the complex nature of the RNase L protein and the CFS
pathophysiology. It also advances efforts to establish whether the RNase L test
may be a marker for a subset of CFS patients.
Demettre E et al: Ribonuclease L proteolysis in
peripheral blood mononuclear cells of chronic fatigue syndrome patients. J
Biol Chem. 2002; July 12.
Review of CFS in adolescents
CFS in adolescents
to the illness in adults, with one important difference: adolescents are more
likely to improve, according to a review article in Contemporary
A review of the pediatric CFS medical literature
that most of the precipitating factors, psychological variables and organ system
effects are similar in adults and children who have the illness. However,
adolescents and children with CFS appear to improve in greater numbers within
three years following onset of the illness. In the authors’ experience, “good
health most of the time” was experienced by more than one-half of their
adolescent CFS patients within one year, by more than two-thirds within two
years and by more than three-quarters within three years.
The authors warn that improvement comes slowly and
unpredictably, with a gradual shift in the ratio of bad to good days, and
relapses may occur in response to stressful events.
Krilov L, Fisher M. CME: Chronic fatigue syndrome
youth: Maybe not so chronic after all. Contemporary Pediatrics.