More cases of Balamuthia encephalitis transmitted via organ transplantation

Late last year, we blogged about the transmission of Balamuthia mandrillaris from an organ donor with an undiagnosed encephalitis in Mississippi to 2 organ recipients (liver and kidney-pancreas) who subsequently developed encephalitis. One recipient died of encephalitis and the other survived with neurologic sequelae. These cases are described in the most recent MMWR. Then there was the report in Clinical Infectious Diseases of transmission of rabies to 2 organ recipients who died. Again the donor had an undiagnosed encephalitis. Seven other cases of transplant-associated rabies had been previously described. Now the Arizona Star and MMWR are reporting another cluster of two Balamuthia encephalitis cases who received organs from a 27-year old man who died of what was thought to be a stroke (no details on brain imaging are included in either report).

Several months ago, I argued that there should be an immediate ban on transplanting organs from donors with undiagnosed encephalitides (and I would now add other neurologic diseases without a confirmed diagnosis) in cases where transplantation is not immediately life-saving (e.g., cornea, kidney, intestine, pancreas, musculoskeletal grafts). And where transplantation is potentially immediately life-saving (e.g., heart, liver), full disclosure of the donor's diagnosis and its implications should be made available as part of the informed consent process. I was surprised that CDC did not make this recommendation earlier, and even more so after additional cases have been reported.

Transplantation associated rabies

There's an interesting and disturbing report in Clinical Infectious Diseases that describes the transplantation of organs to six recipients from a donor with undiagnosed rabies. The donor was a 26-year old woman who presented with an encephalitis-like picture and negative testing for the usual causes of encephalitis. Approximately six weeks post-transplant, it was noted that three of the recipients began to exhibit symptoms similar to the donor. Review of archived brain samples from the donor revealed characteristic histopathologic and electron microscopy findings of rabies. Further investigation about the donor revealed that she had traveled to India where she sustained a dog bite. All of the recipients were treated with rabies immune globulin and vaccine. The two cornea recipients underwent explantation of the corneas, did not become ill, never exhibited any virologic evidence of infection, and survived. The liver recipient also remained healthy and had no virologic evidence of infection; however, it is important to note that he had received rabies vaccine 20 years earlier. The other three recipients (lung, kidney, kidney/pancreas) all died of rabies despite aggressive treatment with the Milwaukee protocol.

A few months ago we blogged about two cases of Balamuthia encephalitis transmitted by an organ donor in Mississippi. Since then, at least one of the infected recipients has died. The common theme here is that both the rabies and Balamuthia infected donors died with undiagnosed encephalitides. While I agree with Eli that a complete analysis of the problem is warranted, I don't agree that actions should wait for the conclusions of such analysis. Interim actions should be taken. It seems to me that at a minimum there should be an immediate ban on transplanting organs from donors with undiagnosed encephalitides in cases where transplantation is not immediately life-saving (e.g., cornea, kidney, intestine, pancreas, musculoskeletal grafts). And where transplantation is potentially immediately life-saving (e.g., heart, liver), full disclosure of the donor's diagnosis and its implications should be made available as part of the informed consent process. I suspect that donors with undiagnosed encephalitides comprise a small fraction of the donor pool anyway, though I appreciate the scarcity of organs for transplantation.

Primum non nocere!