A woman has died after receiving stem cell therapy to treat a kidney ailment at a private clinic in Thailand.
The woman was suffering from an autoimmune disease called lupus nephritis, where her own immune system was attacking her kidneys. Her death has reinforced warnings against 'Stem Cell tourism', where people travel to unlicensed clinics and resort to treatments of dubious value.
Previously a series of medical trials in Europe looked at using stem cells to treat lupus nephritis. They involved using drugs to knock out the patient's immune system. Stem cells from the patient's own bone marrow were then re-injected back into their blood to help re-build their immune system, and help stop the attacks on the kidneys. Out of the 50 patients in the trial, one third suffered relapses or eventually died. The other two thirds showed improvement or even had the disease go into remission.
By contrast, this woman was repeatedly injected with stem cells directly into her kidneys. She later had to undergo dialysis, and then have a kidney removed after a lump formed. She later died from an infection.
Researchers from Chulalongkorn University in Bangkok, Thailand, and the University of Toronto, Canada, analysed the woman's kidney. They found angiomyeloproliferative lesions at the injection sites on the kidney - abnormal growths of blood vessels and bone marrow cells.
Dr Duangpen Thirabanjasak, from Chulalongkorn University, who led the research, said: 'This type of lesion has never been described before in patients, and we believe that this is either formed directly by the stem cells that were injected or that the stem cells caused these masses to form'.
'It's a dreadful reminder reinforcing the absolute necessity for robust safety data in animal models before entering regulated clinical trials', said Chris Mason, director of regenerative medicine at University College London.
The results of the study were published in the Journal of the American Society of Nephrology.