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Fungus In Medical Marijuana Eyed As Possible Cause In California Man's Death

SACRAMENTO (KPIX 5) – Did the medicine contribute to the patient's death? That was the question facing doctors when a California man died from a relatively rare fungal infection.

"It started with a couple patients that were undergoing very intensive chemotherapy and a stem cell therapy, and those patients were very immune compromised," explained Dr. Joseph Tuscano of the University of California, Davis Cancer Center.

Those patients were already in a very serious cancer fight when that fight suddenly became much more complicated with a relatively rare but particularly lethal fungal infection.

"We thought it was strange to have cases of such a bad fungal disease in such a short amount of time," said Dr. George Thompson, a fungal infection expert with UC Davis Medical Center.

The patients were relatively young, in winnable cancer battles. For one of them, it was the fungal infection that proved deadly. So the doctors set out to find that killer, and right away, they had a suspect.

"What struck me is both of these gentlemen were at least medicinal marijuana users, that helped them with nausea and appetite issues that come with the treatment," said Tuscano, who joined with Thompson to investigate further.

Only problem, federal law prohibited them from doing that research at UC Davis, so they joined forces with Steep Hill Laboratories in Berkeley.

"We kind of go on the credo of  'do no harm,'" said Dr. Donald Land, who has been analyzing contaminated marijuana for over a decade.

"We sometimes see 20 or 30 percent of our samples coming through the lab significantly contaminated with molds," said Land, who had plenty of experience finding mold and fungus strains, but this time, he and his team went deeper.

They gathered 20 samples of medical marijuana from across California and took them apart, pulling out a range of dangerous bacteria and fungi which they analyzed right down to their DNA.

Even Land was surprised by the results. "We were a little bit startled that ninety percent of those samples had something on them. Some DNA of some pathogen," he told KPIX 5.

These weren't just any pathogens, they were looking at the very fingerprints of a killer.

"The cannabis was contaminated with many bacteria and fungi, some of which was compatible with the infections that I saw in my patients," Tuscano said.

"Klebsiella, E.coli, Pseudomonas, Acinetobacter, these are all very serious infections for anybody in the hospital. But particularly in that population, the cancer population," Thompson.

One of questions this raises is whether the risk is made worse by smoking, which could send pathogens directly into the lungs, which are particularly vulnerable.

Truth is, there's really isn't much research on any of this.  "But we think now," Thompson says, "with some of these patients, it's really unknowingly self-inflicted form cannabis use."

Cannabis, labeled medicinal, that could pose a lethal threat to already vulnerable patients.

When this research is published it will suggest more warnings for patients with weakened immune systems, because, as Dr. Tuscano explains, "the problem in my opinion is that there's this misconception that these dispensaries produce products that have been tested to be safe for patients, and that's not necessarily the case."

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