AIIMS Doctors Separate 'Parasitic Twin' from 17-year-old in a Rare Surgery

AIIMS Delhi doctors conducted a complex surgical procedure to remove a parasitic twin weighing 15 kg from a 17-year-old boy from UP’s Unnao district. The 'parasitic twin' was separated from the boy through the collective effort of multidisciplinary specialists, a procedure that lasted more than two hours.

Conjoined twins are twins born with their bodies physically connected. The occurrence of conjoined twins is notably rare, with a frequency of one in every 50,000 to 60,000 births. ^[1] However, in extremely rare cases, one fetus stops developing but remains attached to its twin, resulting in an asymmetrical or ‘parasitic twin.’ The other twin continues to develop but is usually born with the limbs, organs, or other tissue structures from its parasitic twin still attached. ^[2]

The Surgical Procedure

The 17-year-old boy had additional lower limbs and external genitalia on his abdomen that belonged to his underdeveloped twin. Throughout his life, he endured unwanted attention and comments from his peers, leading to considerable social isolation and emotional difficulties during childhood. The precise surgery performed by doctors at AIIMS Delhi successfully removed the remnants of the 'parasitic twin,' giving the boy a chance to live as he always wanted. He had faced several physical and mental challenges, which forced him to quit school at a very young age.

The multidisciplinary team, which included skilled surgeons, radiologists, and anesthesiologists, evaluated his condition and performed the surgical removal of the parasitic limb. CT angiography revealed that the parasitic limb's blood supply originated from a branch of the internal mammary artery. The surgery involved precise dissection, vessel ligation of the unwanted limb, and excision of the abdominal cystic mass.

The surgical intervention, lasting between two and 2.5 hours, involved removing the underdeveloped testes and carefully separating the cystic mass from surrounding organs. AIIMS Delhi doctors reported that the teen had a swift recovery and was discharged on the fourth day after surgery.

How Parasitic Twins Differ from Conjoined Twins and Vanishing Twins

Although parasitic twins are a type of conjoined twin, there are notable differences between the two. In the case of conjoined twins, both share some body parts, but they are two functioning individuals. Whether they can be surgically separated or not, both twins can survive and have developed brains. ^[3]

In contrast, with vanishing twins, one of the twins is absorbed by the remaining twin, the placenta, or the mother’s body. Early ultrasound or fetal heartbeat detection confirms the presence of two fetuses, whereas later tests reveal that only one fetus remains. ^[3]

References:

1. Children's Hospital of Philadelphia. Conjoined Twins. CHOP.edu, 2014. Accessed February 26, 2025. https://www.chop.edu/conditions-diseases/conjoined-twins.

2. Cleveland Clinic. Parasitic Twin: Causes, Diagnosis & Removal. Accessed February 26, 2025. https://my.clevelandclinic.org/health/diseases/23513-parasitic-twin.

3. Pietrangelo, Ann. "What Is a Parasitic Twin?" Healthline. Accessed February 26, 2025. https://www.healthline.com/health/pregnancy/parasitic-twin.

‌(Input from various sources)

(Rehash/Jithin Paul/MSM)