SINGAPORE - An elderly woman was given 1,000 times the correct amount of radioactive iodine after a doctor got confused over the dose.
Madam Jeet Kaur developed a thyroid gland disorder following the error in March 2007 and was later diagnosed with cancer.
Two weeks ago, her family reached an out-of-court settlement with Singapore General Hospital (SGH).
But they are now attempting to have the case reopened, accusing the hospital of trying to sweep it under the carpet.
Her son, aviation company boss Prithpal Singh, has written an open letter to Health Minister Gan Kim Yong, saying that the mistake has led to "a major nightmare for all of us". Madam Kaur, who was then 75, went to SGH for a routine check of her swollen lymph nodes. It involved her being given radioactive iodine as part of the screening.
An hour after she got home, Mr Singh received a call from the hospital. He was told something very serious had happened. Doctors were rushing to see his mother and asked him to be present.
When they arrived, they immediately gave her medicine and took her back to SGH for further treatment. It turned out that the doctor had made a mistake over the dose. Instead of giving it in microcuries, he used millicuries, which are 1,000 times stronger.
Mr Singh said his immediate concern was whether the error would lead to cancer. He was told it would not but that his mother would suffer from hypothyroidism as her glands would not produce enough thyroid hormones. She would need medication for life, which the hospital said it would take care of.
Mr Singh said his mother had been active and healthy before the incident. But a month after it happened, she started to lose weight and became increasingly sickly.
In 2010, she was diagnosed with low-grade lymphoma, a cancer of the blood. This meant she required several sessions of chemotherapy and hospitalisation.
The family then decided to take action against SGH. "We realised the medical condition of my mother was a lot worse and more serious than what the doctors had made it out to be," said Mr Singh.
He added that the hospital had insisted it was an "honest mistake" and not negligence. The doctor, who no longer works there, said in his affidavit that he was new to preparing radio-iodine and got confused.
SGH agreed to pay compensation for the overdose but not for the cancer, since there was no proof that it was caused by the excess of radioactive iodine.
The family said they approached a couple of nuclear medicine specialists to act as witnesses, but these experts refused because they did not want to burn their bridges with the hospital.
"We just gave up," said Mr Singh. They settled for the $20,000 offered by SGH.
But some days later, his mother received a bill for more than $4,000 for treatment in 2007 and 2008.
Mr Singh has now written to the minister, saying: "Until today, we do not know if there were any lessons learnt from this incident and what actions were taken... The impression I got was that it was all conveniently dusted away under the carpet."
Dr Andrew Tan, a nuclear physician with Raffles Hospital, said 100 microcuries is the standard amount of radio-iodine used for diagnostic purposes. But higher doses of up to 30 millicuries are used for treating cancer patients.
"Anything above 30 millicuries is considered a high dose," said Dr Tan. He added that giving more than 10 millicuries would almost certainly shrink the glands and cause hypothyroidism. It is unlikely to lead to cancer, he said, although a dose of 1,000 millicuries is linked to a higher risk of blood cancers in younger patients.
The Health Ministry said it had been alerted to the incident and was looking into the case.
Professor Fong Kok Yong, who chairs SGH's medical board, said: "We acknowledge our responsibility for the lapse and had apologised unreservedly to the patient and her family upon uncovering the error."
He added: "She remains in our continued care and we are committed to her well-being."
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