To describe the University of Maryland Medical Center's innovations in transplant surgery as "cutting edge" is becoming less of a play on words and more of an accurate characterization, as minimally invasive transplant techniques continue to evolve.
Dr. Stephen T. Bartlett, chief of the Center's Division of Transplantation, vice chairman of the Department of Surgery and director of the Comprehensive Divisions of General Surgery, was recruited to the University of Maryland in 1991 from the University of California to develop a major clinical and research transplant program. Under his leadership, the program's achievements include Maryland's first simultaneous kidney/pancreas transplant, the state's first successful pancreas-alone transplant, and the distinction of performing more kidney transplants annually than any other U.S. hospital.
The increase in kidney transplants is due in large measure to major advancements made by the University of Maryland in laparoscopic organ removal from living donors. "It was first done at Johns Hopkins Hospital in 1995," says Dr. Bartlett. "We were the second center in the U.S. to do it and I think we popularized the procedure by publishing our experiences early on in the Annals of Surgery in 1997. Of the live organ transplants, 98% of the removals are done laparoscopically and the only ones not done laparoscopically are because the patient has had so much prior surgery or because of obesity or choice." The new technique has eliminated the need for a large incision and shortens recovery time for donors by several weeks, making donation a more feasible option for friends or relatives of a patient in need of a transplant.
Graft loss from rejection has been more common among African-Americans, who go into the transplant process, on average, more sensitized than the general population. For this reason, doctors have traditionally been less likely to refer their African-American patients for transplantation and those who do get placed on transplant lists end up waiting much longer to find organs that are compatible. The University of Maryland's Division of Transplantation, under Dr. Bartlett, has initiated an outreach program based on patient and family education, which is designed to increase kidney transplants among African Americans and decrease waiting time. "By improving communication among African-Americans about living donors, you can increase the odds that they will be able to identify a living donor, particularly within the family, in turn, meaning that the match could be better and, in turn, meaning that you can reduce the risk of rejection and improve long-term success rates," Dr. Bartlett explains. As a result of the outreach program, there has been a reduction in the waiting time to 681 days for an African-American patient to receive a transplant at the University of Maryland Medical Center. Nationally, according to the United Network for Organ Sharing (UNOS) database, African-Americans wait about 1,335 days.
Another area of the Center's study is the transplantation of diabetics. Typically, the patient referred for transplant would be someone who has very poor control of their diabetes or someone who is beginning to experience a secondary complication of diabetes, such as retinopathy, neuropathy or diabetic nephropathy. One such patient is Tom Kelly of Oxford, Maryland. Kelly learned that he had diabetes at the age of eight and discovered early how to adjust his own doses of insulin. His vocation is sailing boats from the United States to just about anywhere in the world and back — alone. He has been on the water and active all of his life, in spite of his illness, and was devastated to learn at age 62 that dialysis would be his only option for survival. Then he met Dr. Bartlett. "He gave me a whole, new, wonderful life!" says Kelly. "I got a kidney and a pancreas from him and went from 55 years of being diabetic to not being diabetic any more. It was a total miracle. I'm doing things that most 66 year olds who were never sick can't do!"
Other facets of Dr. Bartlett's research involve the use of kidneys from older donors and optimal techniques for performing pancreas and islet transplants. "The whole pancreas can be transplanted," he explains, "but the problem with transplanting the whole pancreas is that you're transplanting that whole thing just to get that 1% of beta cells that make the insulin. So, an alternative to the whole pancreas would be to isolate the islets... and reduce the pancreas down to about 5-10 cc of tissue... which can then just be injected with a syringe." An islet transplant is performed as an outpatient procedure, compared to a pancreas transplant, which requires about 7-10 days in the hospital.
In the category of discovery, Dr. Bartlett has derived the most satisfaction from his basic science research and learning how to avoid recurrent auto-immunity in islet transplants — in other words, to prevent the original disease that destroyed the islets and destroyed the beta cells from returning in the transplanted islets. "We first researched that in a diabetic model called the "BB rat," he says. "Now we have shown it on a more definitive model called the NOD (non-obese diabetic) mouse. BB stands for Bio Breeding. That's the laboratory that accidentally discovered the diabetic rat. A clever lab person realized they had something important. It was just an accidental finding in this lab."
Dr. Bartlett wrote the chapter on pancreas transplantation in Greenfield's Textbook of Surgery. He has also authored about 170 peer reviewed papers in the areas of vascular surgery, immuno-suppression and kidney transplantation, pancreas transplant techniques, use of kidneys from older donors and basic science papers on preventing recurrent auto-immunity in islet transplants.
Dr. Bartlett strode confidently into his career, even though there had been no physicians in his family for eight generations. "This is so corny," he says. "I've wanted to be a doctor since I was five or six — actually, before that. My parents gave me an anatomy book when I was in kindergarten and I read it about 15 times."
Cambridge, Maryland was Dr. Bartlett's birthplace and he lived there until moving with his family to Newark, Delaware at age three. He earned his undergraduate degree at Johns Hopkins University, his medical degree at the University of Chicago and spent his residency at the University of Pennsylvania. He continued his training at Northwestern University and then became an associate professor at the University of California Davis before coming to Maryland.
The greatest challenge in organ transplantation, according to Dr. Bartlett, is the organ donor shortage. "Public education about organ donation is really at the root of the process of increasing the number of organ donors in the United States," he says. "The Transplant Resource Center of Maryland, with which I am associated, is the organ bank for this part of Maryland and has a very enthusiastic process for educating the public through hospitals, public service announcements, and through organ donor registration with the Motor Vehicle Administration." Dr. Bartlett believes that by having the public understand organ donation and the transplant process and by eliminating all the myths associated with organ donation, more people who need organs will be helped.
Of concern in any transplant scenario is the issue of immuno-suppression therapy. Future goals for the transplant program include more emphasis on clinical research in this area, particularly moving toward tolerance trials, to perfect techniques to eliminate immuno-suppression from routine transplants. "Some of the most challenging cases might still require immuno-suppression," says Dr. Bartlett, "but for a routine kidney transplant, our goal is to achieve regimens to eliminate immuno-suppression drugs and all untoward side effects that they can produce."
Prednisone, for example, has been successfully eliminated from nearly all transplants because it causes the most complications, from osteoporosis to cataracts to diabetes, obesity and hypertension. "The long-range goal is to eliminate some of the other drugs which are known to have a toxic effect on the transplant itself," says Dr. Bartlett, "and we now realize that some of the immuno-suppressive drugs lead to long-term organ damage and that by eliminating those, we can actually improve success rates rather than make them worse by risking rejection."
Dr. Bartlett predicts that over the next 5-10 years, as cell biologists and geneticists better understand the growth regulation of cells, biologists will be able to create cell lines to suit very specific needs. For example, stem cells could be turned into islet cells or a patch for defective heart muscle or used to generate new liver tissue. "It is quite clear that the basic cell biology and stem cell differentiation is far more complex than was originally hoped," says Dr. Bartlett. "In the long run, however — and I would predict as much as a decade — those kinds of therapies, I think, will be just commonplace."
The dedication of Dr. Bartlett and the transplant team to research is rivaled only by their commitment to providing outstanding patient care and excellent follow-up for the thousands of patients who have come to them for life-saving transplants over the past decade and the thousands more that will come in the future.
Reprinted from the July, 2003 issue of M.D. News, Baltimore-Annapolis edition. Reprinted with permission of Sunshine Media/Lund Media Associates (firstname.lastname@example.org)
by Martie Callaghan