Four Chicago transplant patients have developed HIV and hepatitis C believed to have come from a single donor whose original HIV test may have been a false negative because the infection was too recent to register on screening tests, said health officials yesterday, Tuesday 13th November.

Dr Matthew Kuehnert, director of blood, organ and tissue safety at the US Centers for Disease Control and Prevention (CDC) told the press this was the first time in 20 years that organ donation had infected patients with HIV.

Recent tests have confirmed that the organ donor, and all four patients who underwent transplant operations in three different Chicago hospitals, have tested positive for HIV and hepatitis C, said Kuehnert, who emphasized it was very unlikely that this would have happened “by chance”.

Investigations have shown that nobody else has received contaminated organs or tissue from the infected donor, said Kuehnert.

The CDC will be carrying out its own tests to see if the four patients have been infected with the same strain of HIV and if it matches the strain from the donor.

Health officials are also investigating whether the four patients may have unknowingly passed on the virus during the months since their operations, which took place in January.

Unfortunately the hospitals did not test the patients shortly after their transplant operations, which would have reduced the risk to others, Kuehnert said to the Chicago Tribune.

It would appear, said Kuehnert, that of the three hospitals, Rush University Medical Center, Northwestern Memorial Hospital and the University of Chicago Medical Center, had not followed CDC guidelines for testing patients for HIV shortly after a transplant operation.

According to Kuehnert the organs were donated by a high risk donor, which would suggest they fit more than one criteria of HIV infection risk, for instance being an intravenous drug user, serving a prison sentence, or being a man who has had sex with men in the previous five years.

Mandy Claggett, a spokeswoman for United Network for Organ Sharing or UNOS who set organ donation policy, told Reuters news agency that all the policies were followed and the tests were carried out correctly on the organ donor, but unfortunately they came back as a false negative result.

There are two types of test for HIV, one is quite fast and the other takes much longer. The fast one screens for antibodies, this is the ELISA antibody screening test. Apparently this was the test that gave a false negative on the donor, and it turns out that a repeat test after the infections were discovered, also came out negative. This could happen if the donor had been infected only recently before they died.

The slower test, called the nucleic acid amplification test, or NAT, looks for the genetic material of the HIV or hepatitis C pathogen, and can therefore detect the presence of a virus shortly after infection, before the body has had time to produce enough antibodies to show up in the antibody test.

The problem lies in the balance of risk against speed. The more accurate test takes longer, but that introduces a delay in a process that could be a matter of life and death for the recipient. Also, as Kuehnert told the press, the reason that high risk donors are even considered for organ donation is because there is a shortage of donors.

He said patients on the transplant list who are concerned about the risks should talk to their doctor.

Click here for CDC.

Click here for Reuters report “Four Chicago transplant recipients contract HIV”.

Click here for Chicago Tribune report “Organ patients’ spread of HIV probed”.

Written by: Catharine Paddock