Disease (CJD) is a frightening but nonetheless intriguing disease. It occurs
in most populations at approximately 1 case per million per year. It is
referred to as classical or sporadic CJD to distinguish it from new variant
CJD (nvCJD) of which there have been to date a total of 25 cases and which
is thought to be the human equivalent of bovine spongiform encephalopathy
(BSE). Classical CJD is not contagious but has been transmitted by transplantation
of cornea 1 (world total of 3 cases), dura mater, pituitary
growth hormone and by comtaminated neurosurgical instruments and cortical
electrodes. Although there is rapidly progressive dementia invariably leading
to death usually within months of onset, it is a diagnosis that is only
confirmed postmortem by characteristic spongiform change or immunochemical
identification of the pathological isoform of the prion protein in the
brain. Although it has long been an absolute contraindication to corneal
donation its exclusion can only be achieved by a low threshold of suspicion
as there is as yet no serological screening test. 2
1997 it was revealed that a donor in Scotland who had died from histologically
proven carcinoma of the lung also had CJD, a fact which only came to light
some months later as a result of a routine neuro pathological post mortem
evaluation, although there had been some neurological symptoms shortly
before death. By this time her eyes had been processed by the Corneal Transplant
Service (CTS) Eye Bank in Manchester, the tissue having passed the normal
tests for HIV, Hepatitis C, Hepatitis B, and bacterial and fungal contamination.
Having healthy endothelia the corneas were transplanted into two recipients
and both scleras into a third individual in a total of three different
the information bacame available to CTS the first action taken was to inform
all three transplanting surgeons once the destination of the tissue had
been thoroughly checked. This was only achieved just as the story reached
the national and international press. It proved to be a difficult time
not only for the patients but also eye bank staff, surgeons and UKTSSA
who were actively involved. There are no Department of Health guidelines
for action under such circumstances and consequently there is uncertainty
as to where responsibility lies. Not surprisingly, the press, somewhat
confused over the difference between classical CJD and nvCJD against a
background of major public concern about BSE, were keen to establish if
and where blame could be apportioned. The incident prompted a useful editorial
which put the risk of such an event occurring into context.
implications of the incident are far reaching and a number of changes have
already been made.
receiving expert advice from the Spongiform Encephalopathy Advisory Group
in December 1997, all surgeons offered the three patients explantation
of ocular tissue. Two patients accepted the advice and had further surgery
by January 1998. All three remain well.
Office at UKTSSA now routinely asks if a postmortem on a donor is pending.
No tissue is issued form the CTS Banks in Bristol and Manchester until
such time as the result is known (December 1997).
Eye Bank policy on sclera has been changed to ensure that sclera cannot
be held in stock and that sclera from any single eye is not transplanted
into more than one individual and can always be traced to a named recipient
(i.e. a policy which is in line with corneal transplantation)
Stewart chaired an expert group who undertook and subsequently published
on behalf of the governemnt (April 1998) an independent review of the incident
which contains 18 recommendations. Copies can be obtained from Margaret
Hallendorff at the College.
for retrieval of donor eyes have now been accepted by the College and are
available, including on this website.
All ophthalmic units are expected to have read this document.
ocular tissue donor information form and contrainidication list are now
issued with UKTSSA retrieval boxes (July 1998).
of the Stewart report are under active consideration principally by the
Ocular Tissues Standards and Audit Group (OTSAG). This Group was established
in 1996 and seeks to define essential and best practice in the fields of
ocular and non-ocular tissue transplantation. The following proposals are
currently under consideration:
first time during 1997-98 procurement rates appear to be falling. Units
should aim to procure preferably twice as many eyes as those of which they
use any part. To do so would compensate for the significant discard rate
that occurs during eye banking which ensures that only corneas with high
endothelial cell counts are issued for transplantation. (The Department
of Health recognises the time and commitment given to eye retrieval and
a scheme has operated for some years to reimburse those units who contribute
a significant net supply of donor tissue).
College of Ophthalmologists should develop a portfolio of documents defining
standards in the transplantation of the cornea, sclera and all other ocular
and non-ocular tissues into the human eye.
should be compiled and updated by OTSAG which is accountable to the Royal
College of Ophthalmologists and to the Corneal Advisory Group at UKTSSA.
regularly undertaking ocular tissue transplantation should contribute to
the supply of ocular tissue for transplantation and research nationwide.
should be undertaken according to guidelines, by trained medical or non-medical
ophthalmic surgeons who undertake ocular tissue transplantation should
have knowledge of the procedure of eye procurement and banking, understand
the unique risks involved and accept that they have ultimate responsibility
for their patients who should be well informed.
Directors of Eye Banks should ensure that all ocular tissue is traceable
to its destination. This includes tissue that is used in research or is
discarded as unsuitable or surplus to requirement in addition to that used
in recipient patients.
ophthalmologists and their junior staff who undertake transplantation of
any kind should actively take part in routine long term follow-up of clinical
outcome. Revised forms for transplant, six month and annual follow-up thereafter
are currently being evaluated.
constructive comments are welcome:
Andrew Tullo, Manchester Royal Eye Hospital,
behalf of OTSAG,
0161 272 6618
RN and Cavanagh HD. Transplantation of corneal tissue from donors with
disease of the central nervous system . Cornea 1995; 14: 547-53
M, Wiltfaug J, Schutz E et al. Diagnosis of Creutzfeld-Jacob Disease
by measurement of 5100 protein in serum: a prospective case control study.
Brit Med J 1998; 316: 577-82
Allan B, Tufts S. Transmission of Creutzfeld-Jacob Disease in corneal
grafts. Brit Med J 1997; 315:1553-4