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Doctors remove 420 kidney stones 'caused by excessive tofu' from patient in China
The operation to remove hundreds of tiny stones took doctors around two hours
Doctors in China have removed 420 kidney stones from a man's body, blaming an excessive amount of tofu in his daily diet.
Mr He from Zhejiang Province in eastern China, checked into the Dongyang People's Hospital complaining of intense pain in his abdomen last month. A CT scan revealed that his left kidney was packed full of stones, most of them tiny.
Doctors operated on Friday in an agonising procedure that lasted about two hours.
Mr He said he had a history of suffering from kidney stones. Twenty years ago he had 10 stones removed using a procedure called lithotripsy, which sends shock waves to break up stones in the kidney, bladder, or ureter until they are small enough to pass in the urine.
"I have worked as a doctor for 30 years and have never seen so many stones," said Zhou Changchun, the attending surgeon, according to state newspaper Qianjiang Evening Post.
The unusually high number of stones was attributed to the high concentration of gypsum tofu, a popular local food, in Mr He's diet. The tofu contains calcium sulphate, which cannot be expelled from the body without a sufficient intake of water.
Wei Yubin, the chief surgeon, said that the kidney would have stopped working had Mr He delayed seeking medical attention any longer, and the kidney most likely removed.
The stones removed by doctors (EuroPics)
This time, the doctors used forceps to remove each stone one by one.
"We spent 45 minutes just taking out the tiny stones," said Dr Wei. "After the operation, my hands and legs were both numb."
Following the operation, Mr He took his stones home with him in a plastic bag.
The medical name for kidney stones is nephrolithiasis. If the stones cause severe pain, this is known as renal colic. Most kidney stones are small enough, between 4 to 5mm in diameter, to be passed naturally.
Kidney stones are quite common and usually affect people aged 30 to 60 years. It is estimated that renal colic affects about 10 to 20 per cent of men and three to five per cent of women, according to the NHS.