Dede, now 35, baffled medical experts when warty "roots" began growing out of his arms and feet after he cut his knee in a teenage accident.
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The welts spread across his body unchecked and soon he was left unable to carry out everyday household tasks.
Sacked from his job and deserted by his wife, Dede has been raising his two children - now in their late teens - in poverty, resigned to the fact that local doctors had no cure for his condition.
To make ends meet he even joined a local "freak show", parading in front of a paying audience alongside victims of other peculiar diseases.
Although supported by his extended family, he was often a target of abuse and ridicule in his rural fishing village.
But now an American dermatology expert who flew out to Dede's home village south of the capital Jakarta claims to have identified his condition, and proposed a treatment that could transform his life.
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After testing samples of the lesions and Dede's blood, Dr Anthony Gaspari of the University of Maryland concluded that his affliction is caused by the Human Papilloma Virus (HPV), a fairly common infection that usually causes small warts to develop on sufferers.
Dede's problem is that he has a rare genetic fault that impedes his immune system, meaning his body is unable to contain the warts.
The virus was therefore able to "hijack the cellular machinery of his skin cells", ordering them to produce massive amounts of the substance that caused the tree-like growths known as "cutaneous horns" on his hands and feet.
Dede's counts of a key type of white blood cell are so low that Dr Gaspari initially suspected he may have the Aids virus.
But tests showed he did not, and it became clear that Dede's immune condition was something far rarer and more mysterious.
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Warts aside, he had enjoyed remarkable good health throughout his life - which would not be expected of someone with a suppressed immune system - and neither his parents nor his siblings have shown signs of developing lesions.
"The likelihood of having his deficiency is less than one in a million," Dr Gaspari told the Telegraph.
Dr Gaspari, who became involved in the case through a Discovery Channel documentary, believes that Dede's condition can be largely cleared up by a daily doses of a synthetic form of Vitamin A, which has been shown to arrest the growth of warts in severe cases of HPV.
"He won't have a perfectly normal body but the warts should reduce in size to the point where he could use his hands," Dr Gaspari said.
"Over the course of three to six months the warts should be come smaller and fewer in number. He will be living a more normal life."
The most resilient warts could then be frozen off and the growths on his hands and feet surgically removed.
Dr Gaspari hopes to get the necessary drugs free of charge from pharmaceutical firms. They would then be administered by Indonesian doctors under his supervision.
Still intrigued by the origins of Dede's peculiar immune condition, the doctor would like to fly him to the United States for further examination, but fears the financial and bureaucratic barriers would prove too difficult to overcome.
"I would like to bring him to the US to run tests on where his immune condition has come from, but I would need funding and to get him a visa as well as someone to cover the costs of the tests," he said.
"I've never seen anything like this in my entire career."
- "Half Man Half Tree", part of the "My Shocking Story" series, will be shown on the Discovery Channel at 9pm on Nov 15. For more details visit the programme's website.
