Doctors in the Indian capital, Delhi, have performed a life-changing surgery on a 17-year-old boy to remove his “parasitic” twin that was attached to his abdomen.
A parasitic twin is an underdeveloped conjoined twin that relies entirely on the host twin for survival.
They are extremely rare, with less than one case occurring per 100,000 births.
The teenager who had a fully developed extra set of limbs and a pelvis – sustained by a chest artery – underwent a two-hour surgery at Aiims hospital in Delhi.
Dr Asuri Krishna, who led the team of specialists, said the surgery was particularly challenging because of the patient’s age.
“Only 40-50 cases of parasitic twins have been documented in world medical literature and, in those cases, the surgery had been attempted on children,” Dr Krishna told the BBC.
With insufficient medical literature to guide them, the team had to rely on their “intuition, skill and knowledge”, he added.
Parasitic twins form when one foetus partially develops while attached to the other.
In this case, the teenager had two fully formed legs, buttocks and external genitalia – weighing nearly 15kg – protruding from his abdomen.
Remarkably, the parasitic limbs could feel pain, touch and change in temperature.
Dr Krishna said the first thing they did was identify how interconnected the parasitic and host twins were.
Through scans, the doctors found out that the parasitic twin was attached to the teen’s breastbone and was being supplied blood from a vessel in his chest.
“But there wasn’t much connection with other main organs like the liver or kidneys,” Dr Krishna said, adding that they also found a large cyst in the teen’s abdomen.
The surgery was done in two stages – first, removing the parasitic twin, then extracting the cystic mass from surrounding organs.
A team of doctors, including radiologists, anaesthetists and plastic surgeons, completed the procedure in two-and-a-half hours.
“A mesh of shared blood vessels, nerves and tissues had to be separated. Care had to be taken to see that none of the host’s organs or tissues were damaged,” Dr Krishna said.
During surgery, the teen’s blood pressure dropped dangerously as 30-40% of his blood flowed to the parasitic twin. But the doctors said they were prepared for it and swiftly stabilised him.
The teen was discharged four days after being admitted. He is healthy and has suffered no complications from the surgery, Dr Krishna says.
The teenager’s unusual appearance made him the subject of gossip and ridicule in his neighbourhood in Unnao, Uttar Pradesh. The stares and jokes took a toll on his mental health, leaving him feeling isolated and lonely.
“I couldn’t travel anywhere or do any physical activity,” he told the Indian Express newspaper, adding that he had dropped out of school in the eighth grade.
The 17-year-old told the Express that he was ecstatic and now wanted to live an active life.
“I hope to study and get a job. A new world has opened up to me,” he said.
