Eight Louisiana surgery patients operated on with possibly infected medical instruments are at risk for contracting Creutzfeldt-Jakob disease (CJD), an always fatal neurological disorder, Tulane University Hospital in New Orleans announced Thursday.
CJD is the human form of mad cow disease and occurs in about one in a million people worldwide. It is believed to be spread by prions, mysterious rogue proteins that are not really alive and thus cannot be "killed." Resistant to heat and radiation, prions are unaffected by standard sterilization procedures used for disinfecting medical instruments.
When an unnamed patient at Tulane died after brain surgery in March, the instruments were cleaned and sterilized following routine procedures, hospital officials said. Weeks later, the hospital conducted an autopsy and discovered that he had CJD. The hospital ordered the surgical instruments destroyed, but they had already been used in eight other neurosurgical procedures, said Dr. Alan Miller, Tulane University Health Sciences Center vice president for clinical affairs.
Because the incubation period for CJD can be decades long and the disease is generally confirmed only through an autopsy, the eight living surgery patients will have to wait an extremely long time to find out if they have been contaminated. They are receiving counseling and "related medical care," Miller said in a prepared statement.
This is not the first time contaminated surgerical equipment has been implicated in the spread of CJD. In 1977, two teenagers in Switzerland developed the incurable disease after having undergone surgery for brain tumors. The electrodes that apparently transmitted CJD had been cleaned, disinfected and sterilized using benzene, alcohol and formaldehyde.
"None of these agents will eradicate the CJD causative agent," warned an article published by the Association of Operating Room Nurses. The article added, "It is not known how to terminally sterilize power saws (and some other medical devices) contaminated with the CJD agent."
Although some federal agencies have promulgated guidelines for preventing transmission of the disease through surgery, none actually oversees or enforces their implementation, although hospitals' general procedures for cleaning and sterilizing medical equipment do undergo periodic review. Likewise, the Joint Commission on Accreditation of Healthcare Organizations, which accredits most U.S. medical institutions, does not specifically check on steps hospitals take to ensure that prion contamination does not occur. "The standards don't get into details," said commission spokeman Robert Lee.
An incident similar to the Tulane situation occurred last spring at Australia's Royal Melbourne Hospital, where doctors operated on nine patients with instruments previously used during surgery on an individual with CJD. John Thwaites, health minister in the state of Victoria, ordered an official inquiry. "The government and the public cannot tolerate such breaches of infection control," he told the parliament. "The risk of CJD is not eliminated by normal cleaning and sterilization."
Another example occurred last year in England after a woman suffering from depression and mood swings underwent Caesarian section. When doctors diagnosed her with probable CJD in January, the hospital was "able to ascertain seven other women had had Caesarian sections using this theater kit," wrote Dr. Rod Griffiths, West Midlands director of public health, in an e-mail to ProMed, a list serve for infectious disease professionals.
The situations presented ethical dilemmas for the facilities involved. Since there is no treatment for the disease, and those infected are unlikely to develop symptoms for decades, hospitals have struggled with how to approach the problem. The English hospital set up a hotline where worried individuals could call to find out if had been exposed. The Australian hospital simply informed the affected patients. Tulane officials apparently waited nearly half a year before contacting the potentially exposed individuals. The hospital reportedly sought advice from a panel of experts about how to proceed and what to tell the patients.
Transmissible spongiform encephalopathy -- or TSE -- is the name of the family of diseases that includes mad cow and CJD. Although these disorders have been known for decades, infection caused through contamination of medical equipment has received increased attention after the British mad cow scare hit the headlines a few years ago. So far more than 70 people in Europe -- although none in the United States -- have died from a form of CJD that they contracted after eating beef from infected cows. The situation sparked the slaughter and incineration of almost 200,000 British cows and prompted many countries, including the U.S., to ban most beef products from Europe.
With predictions that the number of infected people in the United Kingdom could eventually reach anywhere from the tens to hundreds of thousands, the likelihood of accidental transmission through surgical infection has grown. Although no cases of mad cow disease have appeared in the U.S., the risk of surgical transmission of CJD, is cause for concern. The long incubation period means that at any one time as many as 10,000 Americans could be infected, according to researchers at the Centers for Disease Control and Prevention in Atlanta.
Since prions can remain infectious for years, the reuse of medical instruments can pose risks long after the surgery that might have contaminated them. Cleaning helps, but instruments such as hollow-bore needles and electrodes used in some surgeries can harbor tiny bits of tissue even after undergoing post-surgical procedures -- leading some researchers to propose more disposable equipment for certain procedures.