Doctors in Brazil believe the needles were deliberately pushed into his body through his skin - including 17 discovered in his digestive system.
Police have launched an investigation to discover who carried out the attack amid fears the boy may have been used as part of a sinister black magic ritual.
One of the needles perforated the youngster's left lung. Stunned medics admitted him to hospital in Barreiras in the state of Bahma, north east Brazil, after X-rays showed the 50 metal objects in his abdomen, neck, thorax and legs.
Today it emerged the macabre crime may be linked to a bizarre black magic ritual.
The boy, taken to hospital by a relative on Sunday with stomach pains, has not been named.
His mother, maid Marma Souza Santos, has told police she does not know who is responsible and said his gran used to look after her son while she was out at work.
But she has reportedly claimed in a statement the youngster's stepfather may have used the infant in a black magic ritual. He has denied the claims.
Police chief Helder Fernandes Santana said: 'We are certain someone introduced the needles because of the position of some of them in the child's body.
'At the moment we don't know who did it.
'It's such a strange situation. We could be looking at attempted murder, a serious assault or some type of revenge attack. We're not ruling anything out at the moment.'
Doctors at West Hospital in Barreiras where the boy is currently being treated, said they would considering trying to remove sewing needles just under the surface of the boy's skin.
But hospital director Luiz Cesar said none of the needles were endangering his life at the moment - and said he may have to live with them inside his body because of the risk involved in removing them.
He added: 'We're certain the boy didn't swallow the needles of his own accord.
'If he did, they would be in his gastrointestinal tract.
'I've never seen a case of its kind.
'Our priority at the moment is the boy's lung which was perforated by one of the needles.
'Fortunately his life is not in danger.' The boy's dad Gessivaldo Alves added: 'We have faith in God that he is going to get better.'