A new report describes details of the clinical, radiological and pathological findings of four patients who received organs or tissue from a single donor, contracted rabies from the transplant and subsequently died, according to a study in the June issue of Archives of Neurology. Previous articles have already described summaries of these cases, which occurred in May 2004.
Rabies has been described as an unpredictable disease whose only consistent feature is its uncharacteristic symptoms, according to background information in the article. Although rabies cases in the United States are rare, the incidence of rabies may be underreported because of the absence of a known animal exposure, lack of clinical suspicion, difficulty in making a diagnosis before death and the decreasing frequency of autopsies. There have been eight documented cases of rabies transmission through corneal transplants, including one in the U.S., but there have been no previously reported cases of rabies transmission through solid organ transplant.
Elizabeth C. Burton, MD, of Baylor University Medical Center in Dallas, and colleagues, describe detailed features of four cases of transplant recipients who received organs or vascular tissue from a common donor who developed a rapid neurological deterioration and died with clinically unsuspected rabies infection. The two kidneys, the liver and blood vessel tissue were successfully transplanted into four recipients. All four transplant recipients also developed rapidly progressive neurological disease and died within 48 days following transplant.
Although antemortem diagnosis of rabies is possible the possibility of rabies is often not considered, particularly in the absence of a known exposure, the authors write. In the cases discussed here, a definitive diagnosis of rabies was not made until after death, similar to previous reports in which more than one third of cases were not diagnosed antemortem primarily because of lack of clinical suspicion. This series of cases along with a subsequent case bring the number of reported human rabies cases since 1980 in the United States to 55. Even if the number of U.S. rabies cases increased by 100-fold, given the population and known organ donation rate, a conservative estimated risk of rabies infection through solid organ transplantation is less than 1:1,000,000,000,000.
However, these cases demonstrate that the risk for transmission of rabies infection through solid organ transplantation exists, and the diagnosis should be considered in any rapidly progressing neurological disease, the authors conclude.
In an accompanying editorial, Transmitting Rabies Through Organ Transplatatio, Karen L. Roos, MD, of Indiana University School of Medicine in Indianapolis, writes It is probably unrealistic to suggest that patients who die of atypical or unknown acute neurological illnesses have histopathological examinations of brain tissue prior to their organs being transplanted. It is reasonable, however, to suggest that this be done as soon as possible with the plan to treat the organ recipients if a treatable infectious disease is detected.
Roos warns that serological testing must be interpreted with caution, but points out that it can be performed to detect antibodies to rabies virus, St. Louis encephalitis virus, West Nile encephalitis virus, eastern equine encephalitis virus, Rocky Mountain spotted fever, Lyme disease, and ehrlichiosis.
Transplantation surgeons will transplant organs from any patients but those with Creutzfeldt-Jacob disease or metastatic cancer, Roos concludes. They argue that without the organs, their patients will die. But the organ recipients in the Burton et al case report died of rabies virus infection, and if they hadnt received these organs, healthy organs may have been available subsequently. Neurologists should play a role in the decision to transplant organs from patients with acute progressive, and potentially infectious, neurological diseases.
References: Arch Neurol. 2005; 62:873-882 and Arch Neurol. 2005; 62:855-856