A Toronto hospital is treating several cases of extensively drug resistant tuberculosis

Helen Branswell:

A Toronto hospital is treating several cases of extensively drug resistant tuberculosis, with one of the patients being held in isolation under court order, the doctor overseeing the treatment said Monday.

Public health experts fear the dangerous strain of tuberculosis, which is susceptible to very few of the antibiotics normally used to treat TB, is a global health crisis in the making.

Dr. Monica Avendano, the physician in charge of the tuberculosis service at West Park Healthcare Centre, said since 2004 her unit has treated five or six patients with XDR TB, as it is called. All the patients were either infected abroad or infected by a family member who picked up the highly resistant strain elsewhere, she said.

"Currently I am treating three," said Avendano. "All of them have a previous history of tuberculosis that was not well managed."

Multi-drug resistant TB and the more difficult extensively drug resistant TB can arise one of two ways. A person with tuberculosis can fail to take all their medication, as in the case of the "not-well managed" patients to which Avendano referred. This spotty treatment allows the bacterium to survive the assault of the drugs and develop resistance to them. Or a person can be infected by contact with a person sick with XDR TB.

Two of the cases Avendano has treated fall into this latter category.

"Both of the cases are young women who went to their country of origin to look after their ailing grandmothers. And the ailing grandmothers gave them TB. And it was XDR TB," she said.

She did not identify the countries involved. XDR TB has been found in a number of places, including China, South Africa, and many republics of the former Soviet Union. It is believed to have spread, still at low levels, from these jurisdictions to developed countries.

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