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JOURNAL: Lancet. 2004;363:411-412, 417-421, 422-428
AUTHORS: Robert G. Will
ABSTRACT: — Blood transfusion may be a mode of transmitting variant Creutzfeldt-Jakob disease (vCJD).
COMMENTARY: 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.
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."