The horror: CJD exposed patients wait and wonder
We could not conclude there was no risk.’
Imagine having to tell a neurosurgery patient that as a result of their recent procedure they may have been exposed via contaminated surgical instruments to the exceedingly rare but legitimately real risk of transmission of Creutzfeldt-Jakob Disease (CJD), a prion infection of the brain that is largely untestable and completely untreatable.
Estimates of incubation periods vary from years to decades, but once onset of symptoms begin — problems with muscular coordination, personality changes, impaired memory — the disease progresses rapidly and invariably toward death.
"Part of the tragedy of this disease is that there is no effective treatment once symptoms onset," says Elizabeth Talbot, MD, an infectious disease physician at Dartmouth-Hitchcock Medical Center in Lebanon, NH, who is assisting in the public health investigation of eight surgical patients in Concord, NH.
The patients were informed they were exposed to surgical instruments at Catholic Medical Center (CMC) that were previously used on a male patient who died with suspected sporadic CJD, public officials report. An autopsy was being conducted on the index case by the National Prion Disease Pathology Center in Cleveland. Results were expected by the end of September, Talbot says.
With so few cases of acquired CJD, it is difficult to give a prognosis on the exposed patients, Talbot said. However, iatrogenic CJD may have a shorter incubation period than the other types, with onset of symptoms occurring within an average of four years in the few known cases, she adds.
An open letter
"On Wednesday, September 4, Catholic Medical Center announced that a patient who had neurosurgery at CMC, and is now deceased, may have arrived at CMC with a rare and very serious illness called Creutzfeldt-Jakob Disease," Joseph Pepe, MD, president and CEO of CMC, said in an open letter. "[Investigators] have identified eight patients who may have been exposed to the disease through neurosurgical instruments used on the initial patient at CMC. We have reached out to those patients to let them know about the situation, and to let them know we will be here to provide ongoing care, support and information."
For all medicine’s advances, it could scarcely look more helpless in the final stages of CJD, which are marked by a progression of involuntary muscle jerks, impaired vision and blindness, then a loss of speech and movement that often heralds a final coma state, according to the National Institute of Neurological Disorders and Stroke (NINDS). Pneumonia and other infections often develop during the coma, leading to what must be a merciful death for these end-stage CJD patients. Given the very low probability that CJD was transmitted by contaminated surgical equipment in the first place, exposed patients and even providers must be tempted by the thought that it may have been better not to know. But ethics demand full disclosure, Talbot says.
"Patients in general appreciate their right to know if there has been an untoward event during a procedure," she tells Hospital Infection Control & Prevention. "Although there is some controversy about making a report of a possible’ disease when the outcome will be so devastating, we deemed that the ethics mandated full disclosure to these patients, who now can handle their own life decisions based on full information. We believe it was handled appropriately and patients do have a right to know."
Thought the risk of transmission is considered extremely low, "after extensive expert discussion, we could not conclude that there was no risk," says José Montero, MD, director of public health at the New Hampshire Department of Human Health Services.
Variations on a grim theme
According to NINDS, CJD is generally broken down into the following categories.
Sporadic: In sporadic CJD, the disease appears even though the person has no known risk factors for the disease. This is by far the most common type of CJD, accounting for at least 85% of the 200 cases that occur each year in the U.S.
Inherited: About 5 to 10 percent of all CJD cases are inherited. These cases arise from a mutation, or change, in the gene that controls formation of the normal prion protein. In hereditary CJD, the person has a family history of the disease and/or tests positive for a genetic mutation associated with CJD.
Acquired: In acquired CJD, the disease is transmitted by exposure to brain or nervous system tissue, usually through certain medical procedures. There is no evidence that CJD is contagious through casual contact with a CJD patient. Since CJD was first described in 1920, fewer than 1% of cases have been acquired CJD.
"The features that this patient manifested are suspicious for sporadic CJD," says Talbot, noting that the man had no family history of the disease. "Variant CJD, which goes by the nickname of mad cow’ disease occurs in much younger persons."
Variant CJD — which became something of a tabloid darling when the first dramatic cases occurred in "mad" cows and Englishmen in the United Kingdom in the late 1980s — is acquired in large part by eating food contaminated with the brain, spinal cord or digestive tract of infected cattle. Cooking does little good because, as with sporadic CJD on surgical instruments, CJD prions are virtually impervious to heat.
With all of these varieties of disease, variables and flat-out unknowns, it is little wonder that infection preventionists dealing with CJD exposure investigations and patient notifications find that the legitimate medical issues can quickly become engulfed by a swirl of misinformation, media hype, and public panic. However, transmission risks cannot be dismissed outright because of the documented cases where CJD has spread from patient-to-patient on surgical instruments.
In addition to iatrogenic transmission of CJD linked to the use of contaminated human growth hormone, dura mater and corneal grafts, there are six documented cases linked to the use of contaminated equipment, according to the Centers for Disease Control and Prevention. Four cases were associated with neurosurgical instruments, and two with stereotactic EEG depth electrodes. Of note, since 1985 all human growth hormone used in the United States has been synthesized by recombinant DNA procedures, eliminating the risk of transmitting CJD by that method.
"All of these equipment-related cases occurred before the routine implementation of sterilization procedures currently used in health care facilities," the CDC reports. "No such cases have been reported since 1976, and no iatrogenic CJD cases associated with exposure to the CJD agent from surfaces such as floors, walls, or countertops have been identified."
Hospital used detergent prior to autoclaving
Though it is difficult to know much with certainty about such a rare infection, the lack of a confirmed hospital-acquired case of CJD in almost four decades is likely due in large part to improved sterilization processes, Talbot says.
"Sterilization processing has certainly changed over the years and there are some modeling studies that do suggest that the standard methods that are used for sterilization particularly the use of a detergent prior to autoclaving has a major role in reducing the number of prions that are on instruments after they have been used on a prion contaminated patient in neurosurgery," she says. "[Catholic Medical Center] used detergent ahead of autoclaving."
Made by Medtronic Inc. in Minneapolis, the highly specialized surgical instruments used in the cases were also shared with Cape Cod (MA) Hospital, prompting notification of five patients there. According to published reports, the equipment includes a neuroprobe, a needle-like instrument used to find the precise area of the brain targeted for surgery. The CJD risk to the Massachusetts patients is considered even lower than those in New Hampshire, as the cases involved the spinal cord and not the brain. The five patients have been notified.
CJD usually appears in later life and runs a rapid course. Typically, onset of symptoms occurs about age 60, and about 90% of individuals die within one year. CJD belongs to a family of human and animal diseases known as the transmissible spongiform encephalopathy. Spongiform refers to the characteristic appearance of infected brains, which become filled with holes until they resemble sponges under a microscope.