Friday, December 13, 2013
WATERVILLE -- Colby College anatomy students gave presentations at a public event Wednesday morning on treating asthma with parasites and separating conjoined twins, among other health care topics.
Colby College anatomy class students from left, Erin Bewley, Kali Stevens and Erin Hoover discuss their study on conjoined twins during presentations held at Colby College on Wednesday. Listening at right is professor Thomas Klepach.
Staff photo by David Leaming
How doctors help conjoined twins
One group of students discussed three sets of sisters to illustrate the various ways in which conjoined twins can be connected and the approaches doctors can take.
One case involved sisters from Malta, joined at the pelvis in what doctors call ischiopagus, whose parents refused to allow a surgery until it was ordered by a court in Great Britain in 2001. The surgery would kill one of the infants, which could not live independently; but not performing the surgery almost certainly would cause both of them to die. As expected, the surgery resulted in the death of one sister, while the other survived.
Another set of conjoined twins, Abigail and Brittany Hensel, born in Minnesota in 1990, share many major organs but have two distinct heads, with each sister controlling one arm and one leg attached to a shared torso. Doctors decided that it would be impossible to separate them safely, and that they would have a higher quality of life together. They graduated from college in 2012 and currently star in their own reality show on the Learning Channel.
In 2003, doctors at Children's Hospital in Los Angeles decided that 6-month-old Macey and Mackenzie Garrison, who shared a third leg and intestines, would have a higher quality of life if they were separated. The surgery was successful. Today each child has one prosthetic leg, while the material from the third leg was used to reconstruct their pelvises. A third sister, born at the same time, was not conjoined.
Groups of sophomores took turns at the front of a classroom in the college's science building, where they used projected images to illustrate their chosen subjects, many of which involved rare conditions and little-known branches of medical science.
For the students, the Grand Rounds Oral Presentations represented a significant part of their grades in a class they need to pass to continue on the path toward becoming doctors.
After each presentation, members of the audience, which included physicians, asked challenging questions that tested whether the students had a mastery of the material that extended beyond the note cards many of them read from.
Alex Sisto and Brian Westerman drew heavy fire from questioners after presenting on the emerging field of helminotherapy, which treats disorders such as asthma with hookworms, an intestinal parasite.
Hookworms, which looked like featureless snakes in magnified images on the screen, spend much of their life cycle in the human body, Westerman said.
Helminotherapy research suggests that, as the body tries to defend against the parasites, it creates antibodies that can also defend against allergens without triggering an asthma attack. Because of this, some believe that those who suffer from asthma would benefit by intentionally exposing themselves to a small number of hookworms.
"These parasites can and do help people," Sisto said.
Some questioners weren't buying it.
"Is it going to go anywhere and help people with asthma?" one said. "I have my doubts."
Others asked whether the research had been published in peer-reviewed medical journals, or whether studies on the subject included enough people.
"You guys picked a tough topic to defend," said Alexander Wall, a retired surgeon.
After a different presentation from three students, organizing professor Thomas Klepach asked whether certain parents are more at risk of having conjoined twins.
"Are there genetic markers?" he asked.
"We didn't find any genetic markers in our research," Kali Stevens answered.
Stevens described eight ways in which twins can be joined. Some types of twins cannot be safely separated, including cephalopagus twins, joined at the head, and thoracopagus twins, who share a heart, she said. Others, such as pygopagus twins, joined at the back, share fewer vital organs and can be separated more safely.
Stevens and her two partners, Erin Brewley and Erin Hoover, said afterward that they chose the topic to understand better the field they are all leaning toward -- pediatrics.
They also considered a different condition, anencephaly, in which a baby's brain fails to develop normally. Ultimately, they rejected it as "too depressing," according to Hoover.
Other student topics included moyamoya disease, which constricts blood flow to the brain; those who suffer from seizures whenever they are startled; and infective endocarditis, an infectious agent that lives in the mouth and can be transmitted to the heart through the bloodstream when the mouth is damaged.
Klepach said the event, which was open to the public, was a way for community members to share in the college's medical education.
Matt Hongoltz-Hetling -- 861-9287