Recently we have learned that 15 patients in New England were exposed to a rare infection called Creutzfeldt-Jakob disease (CJD) when neurosurgical instruments contaminated with the infection were used in their care. Each had undergone a brain or spinal surgery in early 2013, and now their future was uncertain.
Creutzfeldt-Jakob disease is caused by an infectious agent called a prion — as is ”mad cow disease.” Originally discovered in the brain-eating Fore cannibals of Papua New Guinea, prions are misshapen proteins that are the vampires of the protein world. Prions cozy up to normal human proteins and convert them into misshapen proteins themselves. These new prion converts can then turn additional human proteins into misshapen proteins, and a chain reaction sets up. Eventually the accumulation of misshapen proteins crowds out the normal contents of brain cells, spongy deposits of protein litter the tissues of the brain, and victims of prion diseases develop what is called spongiform encephalopathy.
Since prions are resistant to standard sterilization techniques, neurosurgeons can transmit CJD from patient to patient. For instance, doctors might harvest tissue from the nervous system of an organ donor not recognized to have CJD and then the graft recipient will succumb to the infection years later. Early cases of CJD were diagnosed in recipients of human growth hormone derived from ground up pituitary glands. Others developed CJD from contaminated brain electrodes. In all of history, there have been only four reported cases of CJD in patients whose sole risk was to undergo a neurosurgical procedure with instruments contaminated with the infection. However, the discovery that surgical instruments contaminated with CJD still cause an uproar: at Emory Hospital in 2004, fully 98 patients were exposed to contaminated surgical instruments and the group is still being monitored for signs of disease.
Creutzfeldt-Jakob disease takes years to develop. Patients exposed to the infection feel fine for years but then they become moodier and forgetful and over the course of months subtle cognitive defects progress to severe dementia. Patients with CJD forget the names and faces of loved ones, they lose the ability to walk, speak, or swallow, and they lapse into a coma that has proven fatal one hundred percent of the time.
To avoid neurosurgical prion transmission, the instruments used in a patient suspected to have CJD should be destroyed or specially decontaminated. With such measures in practice, it has been thirty years since a case of CJD was attributed to contaminated surgical instruments. At Catholic Medical Center in Manchester, New Hampshire, though, the instruments used to biopsy the patient later diagnosed with CJD were sterilized via standard techniques and put back into use.