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Surgicalcric
02-12-2004, 10:22
Blood Transfusion May Transmit Variant CJD


Laurie Barclay, MD


Feb. 5, 2004 — Blood transfusion may be a mode of transmitting variant Creutzfeldt-Jakob disease (vCJD), according to a case report and public health study and an animal study published in the Feb. 7 issue of The Lancet.

On Dec. 17, 2003, the U.K. announced the death from vCJD of an individual who had previously received a red cell transfusion from a donor who subsequently developed vCJD. Symptoms of vCJD developed in the recipient 6.5 years after the transfusion, and in the donor 3.5 years after the transfusion.

Using the national blood-donor database and the U.K. CJD register, a team from the National CJD Surveillance Unit of Western General Hospital in Edinburgh, U.K., identified 48 individuals, including the subject of the case report, who received a blood component from 15 donors who later developed vCJD.

"Our findings raise the possibility that this infection was transfusion transmitted," senior author Robert G. Will says in a news release. "Infection in the recipient could have been due to past dietary exposure to the BSE [bovine spongiform encephalopathy] agent. However, the age of the patient was well beyond that of most vCJD cases, and the chance of observing a case of vCJD in a recipient in the absence of transfusion-transmitted infection is about 1 in 15,000 to 1 in 30,000."

The clinical presentation and preliminary examination of neuropathology of this patient were typical of vCJD. Although magnetic resonance imaging did not show the classical pulvinar sign seen in most cases of vCJD, fluid attenuated inversion recovery sequences with the highest sensitivity were not obtained. The red blood cells transfused in this patient were not leucodepleted, but the authors note that the efficiency of leucodepletion in reducing infectivity is uncertain.

The surviving recipients of blood transfusions from donors who later developed vCJD are being informed of their possible increased risk of developing vCJD and warned not to donate organs or blood.

"To date, no case of vCJD has been identified with a history of exposure to fractionated blood products," the authors write. "The most direct action to reduce risk is a careful case-by-case evaluation of the need for blood transfusion."

The National Blood Service supported this study.

In an animal study in the same issue of The Lancet, Corinne Lasmézas and colleagues, from the French Atomic Energy Commission, compared the degree of tissue infectivity among macaques with oral or intravenous exposure to tissue containing the BSE agent.

Using the misfolded prion protein as a marker, they found that the degree of organ infectivity was similar regardless of the route of entry, and that tonsil tissue was the most strongly infected. In addition to expected concentrations of prion protein in the brain and spinal cord, it was also present in the autonomic nervous system, in peripheral nerves, and in Peyer's patches in the gut, suggesting possible risk of transmission from endoscopic procedures.

"In view of the high efficiency of transmission of the BSE agent to primates by the intravenous route, the latter should be regarded as a likely route of contamination for vCJD patients with a medical history involving a transfusion during the period at risk," the authors write. "To avoid further contamination to human beings from peripheral tissues, the same precautionary measures taken for primary vCJD cases should apply to possible transfusion cases of the disease."

In an accompanying commentary, Adriano Aguzzi and Markus Glatzel, from the University Hospital of Zurich in Switzerland, note that transmission of vCJD via blood transfusion is shocking but not surprising. Sheep models support possible transmission of prion diseases via blood, even if blood is collected before symptoms appear. By December 2003, 153 cases of vCJD had been reported worldwide.

"The probable existence of subclinical vCJD carriers raises concerns of an iatrogenic human-to-human wave of vCJD transmission," they write. "Public-health authorities are faced with considerable insecurity about the prevalence of subclinical prion carriers, and any human-to-human transmission will complicate estimation of the size of the vCJD epidemic. Although cross-sectional studies to assess the prevalence of prion carriers pose organisational and ethical problems, there is no alternative for assessing the future of the vCJD epidemic."

The authors of both studies and of the commentary report no financial conflicts of interest.

Lancet. 2004;363:411-412, 417-421, 422-428

CPTAUSRET
02-12-2004, 10:32
Slightly off topic, but a friend of ours rec'd the "Nobel Prize" for discovering Prions:

Terry

Eagle5US
02-13-2004, 11:52
Originally posted by CPTAUSRET
Slightly off topic, but a friend of ours rec'd the "Nobel Prize" for discovering Prions:

Terry
You should be certain she gets something special for Valentine's Day :p

The Eagle

CPTAUSRET
02-13-2004, 11:57
Originally posted by Eagle5US
You should be certain she gets something special for Valentine's Day :p

The Eagle

Not that friend, I am speaking of Stan Prusiner a homeboy from DesMoines, Iowa:

Nancy rec'd the NMS in 2000 (our equivalent of the Nobel), and last year Belgiums equivalent, called the Interbrew Baillet Latour:

Terry

Eagle5US
02-13-2004, 15:50
Originally posted by CPTAUSRET
Not that friend, I am speaking of Stan Prusiner a homeboy from DesMoines, Iowa:

Nancy rec'd the NMS in 2000 (our equivalent of the Nobel), and last year Belgiums equivalent, called the Interbrew Baillet Latour:

Terry
YIKES...sorry!!!
Great news though about your other...soon you are going to need an addition just to hold her accolades.

Eagle

CPTAUSRET
02-13-2004, 15:55
Originally posted by Eagle5US

Great news though about your other...soon you are going to need an addition just to hold her accolades.

Eagle

That's funny, she takes all the awards and puts them under the bed, luckily we have multiple homes, thus plenty of beds to store her awards under.

Terry