- Hello Jeff: The article attempts to differentiate cases
of CJD i.e. v CJD, s CJD and CJD. The bottom line is that CJD whether
we call is sporadic or variant is basically the same. A prion which is
a protein simply changes shape or misfolds.
-
- The fact of the matter is that many CJD cases are not
diagnosed and that is the "meat" of the matter.
-
- Patricia
-
- ProMED Mail
-
- (The original version of this report frequently confuses
variant CJD (associated with transmission of the BSE agent to humans),
with the sporadic, iatrogenic, and genetic forms of CJD. I have edited
the text to eliminate some of this confusion. There are precise diagnostic
criteria for variant CJD, which can be viewed at the UK Department of Health
website: http://www.doh.gov.uk/cjd/cjd_stat.htm. -- ProMed)
-
-
- US Concern CJD Screening May Miss Thousands Of Cases
-
- By Steve Mitchell Zwire.co, United Press International
(via COMTEX) 7-23-3
-
- The UK Department of Health website maintains the only
comprehensive source of comparative data on the incidence of the various
forms of CJD in any population. The UK Department of Health monthly reports
are reproduced in ProMED-mail close to the beginning of each month (see
references below). - Mod.CP]
-
- The federal government's monitoring system for cases
of Creutzfeldt-Jakob disease (CJD), a fatal human brain illness, could
be missing tens of thousands of victims, scientists and consumer advocates
have told United Press International.
-
- Variant CJD [abbreviated as CJD (new var.) or vCJD in
ProMED-mail] can be [contracted] by eating beef [from cattle] with mad
cow disease (bovine spongiform encephalopathy - abbreviated as BSE), but
the critics assert that, without a better tracking system, it might be
impossible to determine whether any [cases of sporadic CJD] are [cases
of vCJD] or to obtain an accurate picture of the prevalence of the disorder
in the United States.
-
- Beginning in the late 1990s, more than 100 people contracted
vCJD in the United Kingdom and several European countries after eating
beef infected with BSE. [The mode of transmission of the BSE agent to humans
has not been established conclusively, but is presumed on circumstantial
grounds to be a consequence of consumption of contaminated meat. - Mod.CP]
-
- No case of [BSE] has ever been detected in U.S. cattle,
and the monitoring system of the Centers for Disease Control and Prevention
(CDC) has never detected a case of vCJD . Nevertheless, critics say, the
CDC's system [may] miss many cases of the disease, which currently is not
treatable and is always fatal.
-
- The first symptoms of CJD typically include memory loss
and difficulty keeping balance and walking. As the disease destroys the
brain, patients rapidly progress in a matter of months to difficulty with
movement, an inability to talk and swallow and, finally, death. Spontaneously-occurring
or sporadic CJD is a rare disorder. Only about 300 cases appear nationwide
each year, but several studies have suggested that the disorder might be
more common than thought and that as many as tens of thousands of cases
might be going unrecognized. Clusters of [sporadic] CJD have been reported
in various areas of the United States -- Pennsylvania in 1993, Florida
in 1994, Oregon in 1996, New York in 1999-2000, and Texas in 1996. In addition,
several people in New Jersey developed CJD in recent years, including a
56-year-old woman who died on 31 May 2003. Although in some instances,
a [BSE] link was suspected, all of the cases ultimately were classified
as sporadic CJD.
-
- People who develop CJD [presumably as a result of] eating
BSE-contaminated beef have been thought to develop the specific form of
the disorder called variant CJD. But new research, released in December
2002 [see ProMED-mail post archived as: CJD (new var.) - UK: update 2003
(03) 20030204.0299], [suggests] that the [BSE] pathogen [may] cause both
sporadic CJD and the variant form. "Now people are beginning to realize
that because something looks like sporadic CJD they can't necessarily conclude
that it is not linked to [BSE]," said Laura Manuelidis, section chief
of surgery in the neuropathology department at Yale University, who conducted
a 1989 study that found 13 percent of Alzheimer's patients actually had
CJD.
-
- Several studies, including the Manuelidis study, have
found that autopsies reveal 3 to 13 percent of patients diagnosed with
Alzheimer's or dementia actually suffered from CJD. Those numbers might
sound low, but there are 4 million Alzheimer's cases and hundreds of thousands
of dementia cases in the United States. A small percentage of those cases
could add up to 120 000 or more CJD victims going undetected and not included
in official statistics.
-
- Experiences in [the UK] and Switzerland -- both countries
that discovered mad cow disease in their cattle -- have heightened concerns
about the possibility that some cases of sporadic CJD are due to consuming
mad-cow-tainted beef. Both countries have reported increases in sporadic
CJD since BSE was first detected in British herds in 1986. Switzerland
discovered in 2002 that its CJD rate was twice that of any other country
in the world. Switzerland had been seeing 8 to 11 cases per year from 1997
to 2000. Then the incidence more than doubled, to 19 cases in 2001 and
18 cases in 2002.
-
- The CDC says the annual rate of CJD in the United States
is one case per million people, but the above studies suggest the true
prevalence of CJD is not known, Manuelidis told UPI. Diagnosing CJD or
Alzheimer's is difficult because no test exists that can identify either
disease in a living patient with certainty. So physicians must rely on
the patient's symptoms to determine which illness might be present. Sometimes,
however, the symptoms of one disease can appear similar to the other. The
only way to determine the disease conclusively is to perform an autopsy
on the brain after death. Unfortunately, although autopsies once were performed
on approximately half of all corpses, the frequency has dropped to 15 percent
or less in the United States. The National Center for Health Statistics
(NCHS) -- a branch of the CDC -- stopped collecting autopsy data in 1995.
"If we don't do autopsies and we don't look at people's brains ...
we have no idea about the general prevalence of these kinds of infections
and (whether) it is changing," Manuelidis said.
-
- While autopsies have been declining, the number of deaths
attributed to Alzheimer's has increased more than 50-fold since 1979, going
from 857 deaths then to nearly 50 000 in 2000. Though it is unlikely the
dramatic increase in Alzheimer's is due entirely to misdiagnosed CJD cases,
it "could explain some of the increase we've seen," Manuelidis
said.
-
- "Neurodegenerative disease and Alzheimer's disease
have become a waste-basket" for mental illness in the elderly that
is difficult to diagnose conclusively, she said. "In other words,
what people call Alzheimer's now is [broader] than what people used to
call it, and that has the possibility of encompassing more diseases --
including CJD." The autopsy studies that found undiagnosed CJD cases
raise the question of whether the United States "already has an undetected
epidemic here," Jeff Nelson, director of Vegsource.com, a vegetarian
advocacy web-site, told UPI. "What's the source of that?" Nelson
asked. "Could it be the same source of encephalopathy we saw in minks?"
-
- Nelson referred to an outbreak of a [transmissible spongiform
encephalopathy] in minks in Wisconsin in the 1980s. The origin was traced
back to the animals' diet, which included parts of so-called downer cattle
-- sick cows that are unable to stand, which often indicates a neurological
disease, including mad cow. The mink disease raised concerns about whether
U.S. cattle were carrying a mad-cow-like pathogen even prior to the U.K.
epidemic that began in 1986.
-
- Andrew Monjan, chief of the neuropsychology of aging
program at the National Institute of Aging (part of the National Institutes
of Health in Bethesda, Maryland), acknowledged there has been an increase
in U.S. Alzheimer's cases. However, he told UPI, this probably is due to
the aging of the population -- as people grow older, they develop a higher
risk of developing Alzheimer's. "There's been no change in the number
of CJD cases in the country, and there has been clearly a tracking of the
unusual cases of CJD" that could be due to mad cow disease, Monjan
said.
-
- However, Terry Singletary, coordinator of CJD Watch --
an organization founded to track CJD cases -- says efforts to track the
disease have been close to nonexistent. For example, only 12 states require
such reports. Therefore, many cases might be going undetected, unreported,
or misdiagnosed. If more states made CJD a reportable illness, there would
be more clusters detected across the United States, said Singletary, who
became involved with CJD advocacy after his mother died from a form of
CJD known as Heidenhain variant.
-
- In the 18-year period between 1979 and 1996, he noted,
the country saw a jump from one case of sporadic CJD in people under the
age of 30 -- a warning sign for a link to [BSE], because nearly all of
the U.K. victims were 30 years of age or younger, to 5 cases in 5 years
between 1997 and 2001. "That represents a substantial blip,"
he told UPI. Singletary also said there have been increases in sporadic
CJD in France, Germany, and Italy, all of which have detected mad cow disease
in their cattle.
-
- So far, the CDC has refused to impose a national requirement
that physicians and hospitals report cases of the disease. The agency has
not chosen to make CJD a reportable disease because "making it reportable
is not necessarily directly helpful in surveillance, because in some states
where it's reportable you may not get the physician to report it,"
said Dr. Ermias Belay, CDC's medical epidemiologist working on CJD. Instead,
the agency relies on other methods, including death certificates and urging
physicians to send suspicious cases to the National Prion Disease Pathology
Surveillance Center (NPDPSC) at Case Western Reserve University in Cleveland,
which is funded by the CDC.
-
- However, because autopsies generally are not done, if
a CJD case is misdiagnosed as Alzheimer's or dementia, a correct diagnosis
might never be made, and therefore the cause of death listed on a death
certificate might be inaccurate. Belay told UPI he discounted this possibility.
It is unlikely to happen, he said, because it is easy to distinguish CJD
from Alzheimer's -- the 2 conditions display different symptoms.
-
- Manuelidis disagreed. It can be quite difficult to determine
accurately whether a patient has CJD, as evidenced by her study, in which
respected and competent neurologists and psychiatrists at Yale originally
diagnosed patients with Alzheimer's, yet were wrong at least 13 percent
of the time. Another study conducted at the University of Pennsylvania,
which found 6 percent of dementia patients actually were suffering from
CJD, supports the difficulty in distinguishing the illnesses correctly.
The U. Penn. researchers concluded that: "These results show that
in patients with a clinical diagnosis of dementia, the etiology cannot
be accurately predicted during life."
-
- In addition, the NPDPSC sees less than half of all the
CJD cases each year, so the CDC's investigational system not only is missing
many of the misdiagnosed CJD cases, it also is not conducting autopsies
on most of the detected cases. Belay said that the CDC follows up on all
cases of CJD that occur in people under age 55, as these could be linked
to variant (BSE-related) CJD. But so far, all have turned out to be sporadic
forms of the disease. About 30 cases of the disorder occur each year in
the United States in this age group, while the remaining 270 or so are
older.
-
- The case of a Philadelphia woman who developed a brain
disorder that appeared to be CJD and died from it in 2000 at the age of
29 -- illustrates just how difficult it can be to diagnose the disease.
Her physician, Dr. Peter Crinos of the University of Pennsylvania Medical
Center, ruled out other disorders and felt certain the young woman had
died of CJD, a concern that raised the possibility of a link to mad cow
disease because of her young age. When neuropathologist Nicholas Gonatas,
who had seen CJD before, examined the woman's brain after her death, he,
likewise, was confident he detected the microscopic, sponge-like holes
caused by the disease. But when he sent brain samples to the NPDPSC, the
results came back negative. Gonatas, convinced the surveillance center's
finding was erroneous, sent off 2 more samples, only to have them both
come back negative. Subsequent research, however, has shown the test used
by the surveillance center cannot rule out CJD, said Crinos, an assistant
professor of neurology. "There's no question that the young woman
had a spongiform encephalopathy," Crinos said, but added although
it appeared to be CJD, it is difficult if not impossible to say whether
it was due to mad cow disease.
-
- Crinos told UPI until the CDC implements a better tracking
system, a lot of questions will remain about CJD and cases like the young
Philadelphia woman's. One central question: Why are cases of what is presumed
to be a rare disease popping up in clusters in certain areas of the country?
Crinos said the clustering suggests an environmental or food-borne cause,
but so far, "No one knows the answer to that."
-
- http://www.zwire.com/site/news.cfm?newsid=9882702&BRD=
1713&PAG=740&dept_id=226965&rfi=6
-
- ProMED Mail promed@promedmail.org
-
- [The above article raises some significant issues related
to CJD surveillance in the USA, and factors that may be contributing to
a significant under-reporting of CJD cases. First and foremost, CJD is
not a nationally reportable disease. Even with nationally reportable diseases,
one sees significant under-reporting, probably related to the health care
delivery system in the USA, which is heavily weighted towards private-sector
providers. Unfortunately the private sector is less consistent with disease
reporting to state and federal levels. In the absence of a national mandate
for reporting of a disease, the incentive becomes negligible, so the traditional
"tip of the iceberg" seen in disease reporting shrinks even further.
-
- The study suggesting that up to 13 percent of cases diagnosed
with Alzheimer's and other dementias may be due to CJD points out another
weak link in CJD surveillance. The diagnosis does necessitate an autopsy,
and autopsy rates have declined markedly in the USA, especially in the
elderly. Hence the "Catch 22" -- what is needed for the diagnosis
is an autopsy, but the autopsy isn't performed (as has been the case in
many of the CJD "cluster" reports). The reverse of "seek
and ye shall find" is "don't look and the problem isn't there."
- Mod.MPP]
-
- Patricia A. Doyle, PhD Please visit my "Emerging
Diseases" message board at: http://www.clickitnews.com/ubbthreads/postlist.php?Cat=
&Board=emergingdiseases Zhan le Devlesa tai sastimasa Go with God and
in Good Health
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