New Zealand Creutzfeldt-Jakob Disease Surveillance Registry

The NZ CJD Registry is hosted by the Dunedin School of Medicine and directed by neurologist Dr Nick Cutfield.

Overview

Creutzfeldt-Jakob Disease (CJD) is a fatal disease characterised by rapidly progressing dementia and associated clinical features such as visual symptoms, ataxia, and myoclonus.

CJD and related prion diseases include:

• Sporadic CJD has no known risk factors and accounts for ~85% of prion disease and the majority of NZ notifications.  It occurs at a rate of 1–2 per million per year.
• Accidentally-Transmitted TSEs (Transmissible Spongiform Encephalopathies) may develop in at-risk individuals following exposure to high risk materials such as cadaver-derived human growth hormone, dura mater grafts or exposure to contaminated surgical instruments.   Latency from exposure to disease can be many years.
• Genetic TSEs such as familial CJD and Gerstmann-Straussler-Scheinker disease.
• Variant CJD which in the UK originated from the consumption of beef contaminated with BSE.  There have been no known cases of variant CJD in New Zealand.

Notification

CJD is a notifiable disease in New Zealand.

“Suspected CJD” should be notified both to the New Zealand CJD Surveillance Registry at the Dunedin School of Medicine – cjd.registry@otago.ac.nz – and to the local medical officer of health.

Notification to the CJD Registry requires completion of this questionnaire to allow classification and identification of any risk factors for accidently-transmitted, genetic or variant forms. A checklist is also provided.

Email cjd.registry@otago.ac.nz

• Checklist Risk Assessment and Notification Forms (DOCX)

Creutzfeldt-Jakob disease and other spongiform encephalopathies (Ministry of Health)

Diagnostic criteria

Diagnostic criteria for CJD surveillance (PDF, updated 2017)

CSF RT-QuIC and 14-3-3

NZ CSF samples for CSF protein 14-3-3 and RT-QuiC analyses are done at the Australian CJD surveillance unit based at the Florey institute, Melbourne.

CSF RT-QuIC has much better test characteristics than 14-3-3, however capacity constraints means that the Florey laboratory may request that New Zealand clinicians requesting RT-QuIC have first notified or discussed cases with the New Zealand CJD Surveillance Registry. A minimum of 1mL (as much as possible) of unspun CSF should be sent.

Florey Institute website

Post-mortem examinations

A diagnosis of definite CJD requires pathological confirmation (post-mortem examination of brain tissue for spongiform change and/or positive immunoreactivity to prion protein.  Post-mortems in suspected cases of CJD are performed at the national referral sites for high-risk post-mortems in Christchurch or Auckland and samples may be sent overseas for further analysis.   Clinicians are encouraged to consider and discuss post-mortems with family at an early stage.  The mortuary teams are aware of the need not to cause undue delay to funeral arrangements.

The Auckland LabPLUS website has useful resources, including information for clinicians, families and a post-mortem consent form.

For the South Island, please use the Canterbury information sheet and consent form:

• Canterbury suspected CJD Post-Mortem Information Sheet
• Canterbury suspected CJD consent form

PRNP gene testing

Codon 129 polymorphism status is part of formal CJD strain typing.   In the absence of a family history the chances of identifying a PRNP mutation is low but can occur.  PRNP gene sequencing requires appropriate consent and an adequate DNA sample.  Suitable brain tissue for DNA extraction does not always eventuate; therefore, to protect the possibility of future DNA testing, pre-mortem DNA extraction can be done on a peripheral blood sample.    DNA extraction and storage on peripheral blood can be consented for with the appropriate patient representative by the treating clinician.   Only a clinical geneticist who has counseled wider potentially at-risk family members would request the actual PRNP gene sequencing.

Genetic Health Service New Zealand website

Contact us

Email cjd.registry@otago.ac.nz