Iatrogenic Creutzfeldt–Jakob disease (iCJD) is an acquired prion disease caused by accidental transmission of pathogenic prion protein during medical or surgical procedures. Unlike sporadic or familial CJD, iCJD results from exposure to tissues or extracts contaminated with PrP^Sc. Sources have included neurosurgical instruments, dura mater grafts, corneal transplants, human cadaveric pituitary‑derived growth hormone and gonadotropins, and stereotactic EEG electrodes. The misfolded prion protein initiates templated misfolding of the host’s prion protein, leading to progressive neurodegeneration.
Routes of Transmission, Pathology and Prevention
Since the 1950s more than 400 cases of iCJD have been reported worldwide, the majority associated with injections of human pituitary‑derived growth hormone administered to treat childhood short stature. Other clusters arose from Lyodura brand dura mater grafts used in neurosurgery during the 1980s and contaminated corneal grafts. Incubation periods vary widely from 1 to over 30 years depending on the route and dose of exposure. Clinically iCJD is indistinguishable from sporadic CJD, presenting with rapidly progressive cognitive decline, cerebellar ataxia, myoclonus and characteristic EEG and MRI findings. Histopathology shows spongiform change, neuronal loss and gliosis. Diagnosis is based on a compatible clinical picture plus evidence of high‑risk exposure; PRNP mutation testing is negative. There is no effective therapy.
Risk Reduction and Surveillance
To prevent iCJD, cadaveric pituitary hormones were replaced in the late 1980s by recombinant preparations, and sterilisation guidelines were strengthened. Modern neurosurgical practice uses disposable instruments or prion‑decontamination protocols for procedures involving the central nervous system. Dura mater grafts are sourced from screened donors or replaced by synthetic materials. Eye and tissue banks routinely screen donors for prion disease. Because prions are resistant to standard autoclaving, effective decontamination requires sodium hydroxide or hypochlorite treatments at high temperatures. Continued surveillance through national CJD registries monitors for new iatrogenic cases and ensures rapid public health response if they occur. iCJD illustrates the importance of stringent infection control when handling neural tissues and the long‑term consequences of using human‑derived biological products. Related Terms: Sporadic Creutzfeldt–Jakob Disease, Familial Creutzfeldt–Jakob Disease, Variant Creutzfeldt–Jakob Disease, Kuru, Gerstmann–Sträussler–Scheinker Syndrome