Forum review: Current perspectives
The keynote speaker was Professor Kenny De
Meirleir, Professor of Medicine at the Free University, Brussels, Belgium.
His clinic sees 800 CFS patients every three months, coming from many
parts of Europe. He has 50 papers awaiting publication about this condition,
many dealing with molecular biology as it impinges on aetiology, treatment
and prognosis. This article briefly summarizes some of the large amount
of current research into CFS presented at the Adelaide forum. Professor
De Meirleir presented an epitome of over 5000 research papers on
the topic since 1999. This disease has measurable physical abnormalities,
contrasting with the dearth of adequate science in psychiatric claims.
- CFS is not primarily a depressive
illness, or some sort of psychological problem.
- The abnormalities at the cellular
level explain the clinical abnormalities.
- The biochemical and cellular
chemistry confirm that CFS is a disorder of immuno-vigilance
caused by low grade sepsis and chronic, mostly undiagnosed
infection.
- It is a heterogeneous illness,
a true syndrome, with a clustering of many symptoms and signs,
and a large number of “causes”.
Especially, it is not a single symptom to be called “chronic
fatigue”.
- It may turn out that CFS is caused
by many different diseases, just as “all that wheezes isn’t asthma”.
- There is a chronic over-stimulation
of an increasingly dysfunctional immune system: more activity,
but less effectiveness.
- Activation of anti-viral pathways
plays a central role, especially low molecular weight Ribonuclease
L (RNaseL) and Protein Kinase pathways.
- The role of non-viral micro-organisms
and even non-biological agents, like insecticides or heavy metal
pollution, in activating viral pathways needs to be sorted out.
- The reactivation of latent viruses,
and other micro-organisms, involves profound interactions between
the brain and immune system.
- The gut is central to the initiation
of CFS. Intestinal dysbiosis allows toxins, viruses, bacteria
and heavy metals that must not enter the body to do so.
- The blood-brain barrier is defective,
allowing molecules that must not enter the brain to do so.
- Herpes viruses play a key role
in about 20% of cases with CFS.
- The Final Common Pathway of all
the causes of CFS is Dysautonomia, i.e. autonomic nervous system
dysfunction.
- CFS is a serious, legitimate
illness, devastating to those who have it, with a slow and uncertain
recovery for many. The spectrum of disease extends to the wheel
chair and the bed bound, and it has a significant mortality,
caused both by the often severe effects of the illness and by
suicide. The extreme end of the condition is virtually unknown
to even the most gifted and caring of the medical profession,
who pass the ball to the psychiatrists from where they end up
in anorexia or other clinics.
CHRONIC FATIGUE: SYNDROME
OR SYMPTOM?
In medicine, a “Case Definition” sets out those symptoms
or signs that must be present in a patient to allow a particular diagnosis
to be made. Various attempts since 1988 at the Case Definition of abnormal
fatigue states have foundered on the vagueness of the word “Fatigue”.
Even healthy people get fatigued, physically and mentally, from to
time. It is also found in serious illness including AIDS, cancer and
major depression. How do we distinguish the pathological fatigue of
CFS from ordinary fatigue or numerous fatiguing illnesses?
In
2003, Health Canada convened The Canadian Case Definition Panel for
CFS. For the first time, this Expert Panel moved away from making
the symptom “Fatigue” the main feature of CFS. Rather, they
concentrated on what was unique and central about the fatigue in
CFS. It is not that these patients get fatigued. It is that their
fatigue, and malaise, is made significantly worse with exercise.
Taking
the emphasis away from fatigue as a subjective symptom, one is forced
to describe the connection between fatigue and activity. Fatigue also
embraces mental fatigue, (impaired cognitive function and alertness),
as well as physical fatigue, (lack of energy or strength, often felt
in the muscles). However, this specific type of fatigue is always found
together with some or many evidences of neuro-cognitive, neuro-endocrine,
dysautonomic (e.g. orthostatic intolerance), and immune manifestations,
i.e. it is part of a much bigger “Syndrome”. (Gk. Syn:
together, Dromos: a race track, hence: a running or clustering together,
a bit like the Tour de France bicycle pack.) The essential feature
of the fatigue of CFS is that the patient becomes worse after even
minor exercise, (e.g. putting out the garbage bin), and this persists,
usually for at least 24 hours, but sometimes for days or weeks. Interestingly,
the onset of the severe fatigue may sometimes occur hours after the
trivial exertion, or even the next day, but with the same devastating
mental and physical exhaustion.
Sometimes,
as a result of earlier Case Definitions numerous diseases were lumped
together that had little or nothing to do with each other, apart
from exhibiting fatigue to some degree. For example, depression and
CFS became, in many peoples mind the reverse and obverse of the same
coin.
The
Canadian Case Definition also clearly distinguishes between Symptom
and Syndrome. Indeed, a symptom may be part of a Syndrome, but a
Syndrome may never be reduced to a single Symptom.
According
to the Canadian panel, who between them have managed over 20,000
CFS patients, the Syndrome of CFS may be defined as: a significant
degree of new onset, unexplained, persistent or recurrent physical
and mental fatigue; that significantly reduces ones level of activity;
that with trivial exertion causes a disproportionately increased muscular
and cognitive fatigability; that, as well, is associated with the worsening
of co-existing neuro-immuno-endocrine symptoms; that has a
pathologically slow recovery period, usually 24 hours or longer;
and that has been present for more than six months.
Though
this is not quite the complete Canadian definition, even this should
be enough to distinguish, say, an alcoholic hangover from a potentially
lethal illness like CFS that sometimes may be confused with multiple
sclerosis. Also, thankfully, we can now all be talking about the
same illness and not confusing it with “clinical depression”.
THE CENTRAL ROLE OF A DYSREGULATED,
2-5 OLIGOADENYLATE SYNTHETASE-RIBONUCLEASE L (2-5A synthetase/
RNaseL), INTERFERON INDUCED, ANTI-VIRAL DEFENSE PATHWAY IN CFS.
In
1957, it was discovered that when a virus infests a cell the “interferon” pathway
is activated to destroy (interfere with) the virus. It is now known
that at least 200 molecules and cytokines, (immuno-regulatory substances
that are secreted by cells of the immune system) are involved in this
defensive ploy. The interferon pathway repulses the virus by activating
a molecule in peripheral blood monocytes called Ribonuclease L (RNaseL)
This destroys viral Ribose Nucleic Acid (RNA) within the cell, and
at the same time triggers the removal of the infected cell by inducing
programmed cell death (apoptosis, Greek, “meaning a falling away
from,” i.e. a falling off the planet for that particular cell).
RNaseL is normally inactive within the cell, so that it cannot damage
the large amount of native RNA essential for normal cell function.
(Remember the mantra chanted by students of biochemistry: “DNA
makes RNA, RNA makes protein.)
Inactive RNaseL is “up regulated”, as the Americans say,
by another, smaller, effecter molecule called 2-5 Oligo-Adenylate Synthetase,
(2-5 OAS). This newly activated RNaseL enzyme destroys the viral RNA,
acting like a pair of scissors snipping a paper streamer. Once its
mission is finished, it must immediately “switch off”,
to avoid damage to the normal cell.
Normally,
inactive RNaseL has a molecular weight of 80 kilo Daltons, or 80
kDa, (80,000 in the older terminology). In 1997 it was discovered
that in CFS, and only in CFS, the 80 kDa molecule is partially
or totally replaced by a different, but defective RNaseL molecule with
a molecular weight (MW) of 37 kDa. The more of this low MW 37 kDa
molecule that is present, the more severe is the CFS clinically.
This is well shown in Figure 1. This, incidentally, is difficult
to explain if CFS is primarily a depressive illness.
When
2-5 OAS activates the abnormal LMW 37kDA RNaseL a destructive “rogue
molecule” is let loose. This molecule is extra-ordinarily active,
more that six times that of the usual, activated 80kDa RNaseL one.
Because it resists enzymes that destroy proteins, (proteases) it has
a deadly property, it does not switch off! It persists in the cell, “snipping
away” at normal protein synthesis, enzyme production and numerous
other vital cellular functions. This destructive molecule also consumes
enormous amounts of Adenosine Tri-Phosphate, (ATP), the molecule that
provides energy for the cell. It has been estimated that 70% of the
cells energy production is consumed by this abnormal “up-regulation” of
the interferon pathway. This has been described as a “black hole” for
ATP. Should anyone be surprised that these patients are fatigued?
Low
MW RNaseL fragments also fails to induce apoptosis, keeping the damaged
cells alive, and the immune system dysfunctional.
Low
MW 37kDa RNaseL was discovered by Dr Bob Suhadolnik and his team
at Temple University Medical School, Philadelphia in 1997. This pioneering
discovery of a highly abnormal molecule that is not present in patients
with cancer, AIDS, multiple sclerosis, clinical depression, malingering,
hypochondriasis or normal health has been confirmed independently
in five other molecular biological laboratories around the world, (Belgium,
France, USAx2, and Tokyo). This work casts serious doubt on commonly
held psychological views about the nature of CFS.
Unfortunately,
RNaseL assay, performed on peripheral blood monocytes, is a complicated
and expensive test. However, it is important to remember that,
in 1955, the only method for measuring serum sodium was based on Vogel’s
Text Book of Inorganic Chemistry, and took a PhD scientist half a day
to perform. Today, a high school, work-experience student can
be shown how to get a result in a few minutes. Venite diem, when a
nurse can perform a 37 kDa RNaseL dip-stick assay in a side room of
a psychiatric ward!
The
enzyme that fragments normal 80kDa RNaseL to the low MW 37 kDa RNaseL
form is now known to be Elastase. Currently, it is thought that the
gene sequence in Low MW RNaseL is normal, but it is only a fragment
from the original 80 kDa molecule.
ELASTASE
An inflammatory protease (an enzyme that breaks
down proteins) that is present in leucocytes and monocytes. The level
of elastase activity correlates with fragmentation of RNaseL to an
incredibly high degree, (p<10-18, in a series of 50 patients). Professor
DeMeirLeir and colleagues have detailed a finding that has exciting
implications for the treatment of CFS and multiple sclerosis, which
they consider are both chronic immune diseases. Beta-Lactam containing
antibiotics such as Cephalosporins and the penicillins are also elastase
inhibitors and help restore normal 80 kDa RNaseL levels. The amount
of reversion of the 37 kDa molecule is dose dependent. Interestingly,
over the years some CFS patients have reported feeling better on antibiotics
without any apparent reason. Other antibiotics may have anti-elastase
properties. Lycopene, found in tomatoes, besides being useful in prostatic
and other carcinomas has an active role in promoting apoptosis, countering
the damage done by the 37 kDA molecule.
NATURAL
KILLER CELLS (NK CELLS)
These are a subset of lymphocytes
that act as a first line of defense against abnormal cells, including
damaged and precancerous cells, and cells infected by micro-organisms.
Low NK cell numbers are routinely seen in CFS, but may also be seen
in a variety of chronic immune diseases including HIV infection,
and certain cancers. Again LMW RNaseL assay is a critical discriminator.
PROTEIN
KINASE ACTIVITY (PKR)
This is another enzyme specific for
RNA destruction, and which is also induced by Interferon. It acts by
destroying the continued production of proteins by the virus in an
infected cell. It also initiates apoptosis in damaged cells. In CFS,
a patient’s
continued PKR up-regulation leads to destruction of immune cells,
and a dysfunctional immune system. It is an important marker to help
differentiate CFS from some forms of multiple sclerosis.
NITRIC
OXIDE (NO) DETERMINATION
Nitric oxide is produced
by NO synthetase. It is important in regulating certain normal physiological
responses such as blood pressure and penile erection. Increased levels
over time allow NO to become toxic to cells. In CFS, immune cells
produce significantly high NO levels. This is thought to be part
of the Elastase story, (see above). There is quite a large group
of CFS patients who present with a multiple sclerosis type clinical
picture. NO is normal in MS, unlike CFS.
CHANNELOPATHIES
The Belgium researchers believe that damaged
fragments of RNaseL and 2-5 OAS impair the transport of ions into and
out of cells by interfering with transport protein molecules. Radioactive
studies using isotopes of potassium have confirmed that the total body
potassium in CFS is significantly lowered in CSF, but not so in clinical
depression.
THE
LABORATORY INVESTIGATION OF CFS
If DSM IV is correct, it
should be possible to diagnose major depression even amongst castaways
on a desert island in the absence of sophisticated laboratory testing.
However, to diagnose precisely what is going on, if depression is
not the primary illness, certainly requires such testing. Even if
CFS is strongly suspected it
is also essential to exclude certain diseases which would be tragic
to miss: Addison’s disease, thyroid deficiency, iron anaemia
or iron overload, diabetes mellitus, multiple sclerosis, myasthenia
gravis, auto-immune diseases, cardiomyopathy, tuberculosis, sarcoidosis,
hepatitis and cancer, to name but a few. Recently discovered mitochondrial
based diseases such as MNGIE (Mitochondrial Neuro-Gastric Intestinal
Encephalopathy) should remind us that medical science is an exploding
universe. Some psychiatrists are advising referring doctors not to
investigate CFS patients because this will re-enforce their delusion
that they actually have a significant medical condition, rather than
a highly elaborated self diagnosis, with symptoms refractory to reassurance,
explanation and standard treatment. The question begging behind this
dangerously absurd view should be obvious even to a high school
student of logic.
A USEFUL DIAGNOSTIC PANEL IN CFS
- LOW MW 37 kDa RNaseL ASSAY
- HUMAN LEUCOCYTE ELASTASE
- PROTEIN KINASE ASSAY
- SERUM NITRIC OXIDE
- SERUM URIC ACID (An index of Purine
metabolism)
- NATURAL KILLER CELL (NK) ASSAY
On
the basis of these six tests CFS patients tend to fall into three
broad groups, sometimes with overlap. These have differing aetiologies,
treatment and severities. These are seen in Figure 1, which obviously
does not show definite test values, but overall trends. For example,
a normal patient has no LMW RNaseL. However the severity of all groups
increases as LMW RNase L increases. Levels over 5 units are quite
ill. Some patients, moribund with levels of 500 units are still being
told their problem is in their heads.
Figure 1.

GROUP
1: These have high LMW RNaseL levels,
high uric acid, low Protein Kinase, reasonable NK killer cell levels,
and low or normal NO.
This group, about 15-20% of CFS sufferers, tends
to have a multiple sclerosis type picture. Pain is not a strong feature.
They tend to be associated with one or more of a long list of well
known suspects, micro-organisms such as, brucellosis, Q fever, cytomegalovirus,
glandular fever, Herpes virus 6A, Epstein Barr virus, enteroviruses,
Lyme disease, mycobacteria, Leishmaniasis, mycoplasma; and pesticides,
and heavy metals, to name but a few members of a vast rogues gallery.
A staggering 20% of this group has low grade Herpes virus 6A encephalitis,
a little known fact! Treatment is aimed at removing causes, if
possible, with antibiotics, and anti-viral therapy, often with the
addition of Interferon therapy.
GROUP 2: LMW RNaseL up, PK up or not, Uric acid and NK down a
little, NO is up. This group, about 60% of CFS patients, has pain
as a predominant feature.
Pain is often generalized and does
not follow nerve root distribution. It may be aching, burning, sharp
or shooting. Many patients develop many types of new onset headaches,
including migraines, tension and pressure headaches. There is often
generalized myalgia, and arthralgia. There is an overall reduction
in pain threshold, (allodynia). The pain is often triggered by exercise.
This group is referred to as the ME (myalgic
encephalopathy) group, in contrast with the Group 1, MS type.
GROUP 3: this severely ill group, about 15% of patients, have
very high LMW RNaseL levels, (up to 500 or more), high Protein Kinase
activity, very low serum Uric acid, and severely depleted Natural
Killer Cell activity.
They usually have severe bowel problems,
such as total bowel paresis, or retrograde faecal vomiting. There
is a high mortality in this group, sometimes due to suicide. Many
of these patients are living in survival mode, and are often abandoned
by the medical profession as being in the “too hard basket”.
The gut is an important part of the
immune system. We must get past the notion that it is only a conveyor
belt for nutrients, or some sort of septic tank. If spread out, its
surface absorptive area is about the area of the Sydney Cricket Ground!
All patients at Professor De Meirleir’s clinic have serum Ig
M and Ig A tests against a panel of 12 gut pathogenic bacteria. Any
patients with a positive Ig M for any of these are given a cycle of
one weeks antibiotics, followed by three weeks probiotics. 58% of patients
have improved after three months, and interestingly, the serum Elastase
drops.
Group 3 patients also seem to be helped
by Isoprinosine, an immuno-stimulator drug which has proved helpful
in delaying the onset of AIDS in HIV positive patients.
There is an encouraging support for
the validity of these three CFS groupings. Professor De Meirleir
took a large number of new CFS patients referred to his clinic and
performed all the above six tests before the patients were seen clinically.
On the basis of the test results he penciled onto their files his predictions
as to their clinical symptoms. He was correct in 95% of the cases! The
other 5% had overlap features.
In Sydney in the late 1950's there was an
active Flat Earth Society, which used to distribute regular articles
outside Sydney University’s main gate trying to convince students
that the earth was flat.
At 9.07am, Moscow time, on April 12, 1961, Yuri
Gagarin, the son of a rural carpenter, became the first human to
be blasted into space. Back on terra firma at 11.55am, in those
168 minutes the Russian had reached an altitude of 381 Kms above
the earth and had seen something that no other human being had ever
seen, the earth's curvature! The flat earth theorists never recovered
from this mortal blow.
Suhadolnik's discovery,
in 1997, of a 37 kDa RNaseL molecule, unique to Chronic Fatigue Syndrome,
is already changing the common view that CFS is predominantly a psychiatric
illness. For some, this may be a difficult adjustment of mind set,
like our friends in the Flat Earth Society had to endure. But from
this important discovery will come, hopefully, a new era of understanding
and treatment of this terrible disease.
Acknowledgements:
1. Suhadolnik RJ, Peterson DL et al.
Biochemical Evidence for a novel low molecular weight 2-5A-dependent
RNaseL in chronic fatigue syndrome. Journal of Interferon and Cytokine
Research 1997; 17:377-385
2. Journal of Chronic Fatigue Syndrome. Myalgic encephalitis/Chronic
fatigue syndrome: A clinical working Case Definition. Carruthers, De
Meirleir et al. 2003: Vol11, No1: pages 7-116
3. Chronic Fatigue Syndrome:
A Biological Approach. De Meirleir K, Engelebienne P. CRC Press
4. R.E.D. Laboratories, Brussels, Belgium.
Brochure discussing available diagnostic tests for CFS. (R.E.D. stands
for “RNaseL Enzyme Deficiency”).