Pit bulls are considered to be inherently dangerous compared to other dogs, although dogs of any breed can be truly strong and aggressive. For this 19-year-old woman, a pit bull dog bite led to an amputation of her left ear, leaving her with only a stud earring still in place. To effectively reattach the woman’s ear, doctors avoided challenging surgery and instead turned to an unusual technique — leeches — to temporarily drain the ear for it to makes its own veins, according to a recent study published in the New England Journal of Medicine.

"I was hopeful, but at the same time this is not a commonly performed procedure," said Dr. Stephen Sullivan, a plastic surgeon at Rhode Island Hospital in Providence who operated on the young woman, HealthDay reported. The Food and Drug Administration approved the use of leeches in 2004 for all types of amputation situations. Typically, leeches are used more commonly for finger amputations, although the procedure has been done less than 50 times around the world.

Sullivan and his surgical team were trained to reattach severed organs, but the dog attack victim’s ear, however, was torn, which made the surgery more challenging. The team was able to find a tiny artery only 0.3 millimeters in diameter and reattached the vessel to the woman’s blood supply with three microscopic stitches. Since the body has two types of blood vessels — arteries — ones that come from the heart to the tissues — and veins — ones that bring the blood back from the tissue to the heart, the surgeons needed to make sure they could locate both in the reattached ear. Although the artery was able to bring back fresh blood to the reattached ear, a vein was missing to drain the blood back to the body.

This led the researchers to use bloodsucking leeches to aid with ear reattachment for the female patient. "The body is very efficient at making new arteries and veins, so the leeches are temporary," Sullivan told LiveScience. "They act as temporary drainage for the ear while the ear makes its own new veins." The woman would remain in the hospital for a 17-day leech treatment for her left ear.

To ensure the leeches were effectively draining away the patient’s deoxygenated blood, the nursing staff waited longer and longer in between periods of replacing the leeches. During this time, the ear began to grow its own veins to drain the reattached tissue. Now, the woman’s scar is barely visible, and the damage did not affect her hearing, making a full recovery.

Leeches aid ear reattachment for woman after dog attack
19-year-old woman has ear torn off by pit bull leaving her with stud earring still in place, but is later reattached with the help of bloodsucking leeches. Photo courtesy of NEJM. NEJM

This patient’s “tough and go” procedure was very dangerous because, at first, the surgeons were only allowed to hook the arteries back up, but not the veins, and for ear reattachment, both are needed. The leeches, “an organic talent,” is considered to be more effective than what scientists, engineers, or doctors have done, according to Sullivan. The leeches were a major part why the 19-year-old patient was able to treat her severed ear.

However, doctors, like Dr. Sam Marzo, ear expert and medical director of the Hearing and Balance Center at the Loyola University Health System, in Oakbrook Terrace, Ill., believes leech intervention may not be convention, but it can be useful when done properly as he has done it himself. He cautions people to not just use any random leech for amputations because they can be dangerous. The best leeches to use are those of medicinal-quality that are sold by companies and grown in a lab under low-bacteria conditions. "And for this whole thing to work you do have to have enough blood supply present," he told HealthDay.

Leeches have been making a comeback as doctors' medical helpers since they are widely used in American hospitals, but they have been used for medical purposes for thousands of years. Leeches are not recommended for patients with HIV and AIDS, and they are also not recommended for patients who are on immunosuppressive drugs due to the risk of bacterial sepsis, which can worsen their conditions.

Source: Sullivan SR, Taylor HO. Ear Replantation. The New England Journal of Medicine. 2014.