Deborah Bethards, M.D.
Most gastroenterologists have encountered patients who complain of chronic constipation. Colonoscopy shows no anatomical abnormalities. Nonetheless, conservative treatment with laxatives and bulking agents brings only temporary, minor relief. After several failed treatment attempts, the patient is distressed, uncomfortable and anxious; the gastroenterologist is frustrated. Deborah Bethards, M.D., a gastroenterologist at Penn State Hershey Medical Center’s Neurogastroenterology and Motility Clinic explains, “Failure of conservative treatment to resolve constipation should be a red flag. With no other detectable abnormality, the possibility of a chronic pelvic floor disorder that primarily affects women—known as dyssynergic defecation—should be considered.”
With this disorder, the rectosigmoid area does not function properly so that during attempted defecation, paradoxical anal contraction occurs, and pelvic floor muscles fail to relax. The result is that stool is retained in the rectum. If left untreated, complications such as fecal impaction, rectocele, megacolon, and fecal incontinence may occur. Continue reading
Douglas G. Field, M.D.
Proper daily nutrition is a necessary part of growth and development and usually a source of comfort and pleasure. But for many pediatric patients with congenital or acquired medical issues or behaviorally-based impairments, “Feeding problems can be a source of stress for patients, parents, family members, and may endanger the child’s overall health and development,” according to Douglas Field, M.D., a pediatric gastroenterologist and medical director of the Penn State Hershey Pediatric Feeding Program.
Field, along with Keith Williams, Ph.D., B.C.B.A., director of the pediatric feeding program and practicing behavioral psychologist, have tailored the program to provide diagnostic, treatment planning, and interventions for children with problems ranging from food refusal to motor impairments that hinder proper swallowing. Prior to their appointments at Penn State Hershey, both Field and Williams worked in the Pediatric Feeding Disorders Program at the Kennedy Krieger Institute in Baltimore, Maryland. Continue reading
Douglas B. Stairs, Ph.D.
The rising incidence of Barrett’s esophagus (BE) over the past two decades, coincident with increases in obesity, chronic heartburn, and gastroesophageal reflux disease, has focused attention on questions about how to monitor and treat these patients. About four in 1,000 BE patients annually develop esophageal adenocarcinoma (EAC), a 30- to 40-fold greater risk than in the general public. EAC, in turn, is linked to five-year survival rates of only about 20 percent. While early identification of high-risk BE patients is critical to improve EAC survival, factors predictive of cancer progression have not been identified. Continue reading
Crohn’s disease and ulcerative colitis, collectively known as inflammatory bowel disease (IBD), are chronic conditions that typically emerge early in life and exact a heavy and costly burden of disability and illness over time. In 1998, physicians and researchers at Penn State Milton S. Hershey Medical Center and Penn State College of Medicine made a long-term commitment to investigating the causes of IBD as a means toward identifying novel therapeutic targets and improving patient care. This has involved establishing and growing the area’s first IBD-dedicated BioBank. Today, the IBD BioBank consists of three inter-related components: an IBD patient registry that characterizes the clinical factors that define subcategories of IBD; a DNA bank derived from patient leukocytes immortalized by viral transformation; and an IBD tissue library, harvested at the time of surgery.
Walter Koltun, M.D.
Walter A. Koltun, M.D., explains, “Because about 25 percent of patients with IBD have a family history of the disease, a crucial starting point for the IBD BioBank was to establish a patient registry to gather medical and demographic data not only from IBD patients but also their family members. Since beginning this work in 1998, we now have nearly 1,400 patients, some with three generations of family members entered into the registry. This is a powerful tool for investigating not only the genetic basis of the disease but also environmental, microbiological and epigenetic IBD risk factors.”
For patients with inflammatory bowel disease (IBD), surgery is often necessary to manage symptoms and address disease-related complications. Such surgery is particularly common for patients with stricturing or fistulizing Crohn’s disease, patients with ulcerative colitis whose disease is not adequately managed with medication, and those with precancerous lesions. Surgical interventions vary according to the disease. Because Crohn’s disease can involve any segment of the gastrointestinal tract, surgical intervention is unlikely to be curative and is reserved to treat the complications of the disease such as obstruction or fistuli. As Walter Koltun, M.D., explains, “Excessive or repeated resection can potentially leave a Crohn’s patient with crippling short bowel syndrome and so alternate surgical therapies are performed such as stricturplasty, which overcomes the obstruction but minimizes resection.”
Inflammatory bowel disease (IBD), has increasingly been a focus of clinical attention at Penn State Hershey Medical Center. The multidisciplinary care needed by these patients has brought together surgeons, gastroenterologists, radiologists, nutritionists, and other sub-specialists to foster the creation of an IBD center focused on providing excellence in IBD patient care and promoting access to cutting-edge research and treatments. This initiative has been directed by Walter Koltun, M.D., F.A.C.S., F.A.S.C.R.S., chief, Division of Colon and Rectal Surgery, and Emmanuelle Williams, M.D., assistant professor of medicine. Koltun explains, “The Penn State Hershey IBD Center has three major components that include a multidisciplinary patient care clinic where surgeons and gastroenterologists see patients together; educational and training programs for both medical professionals and patients; and, an IBD research program that includes benchtop basic science and clinical trials of new, investigative treatments.”
Emmanuelle Williams, M.D.
Inflammatory bowel disease (IBD) is associated with a significantly higher risk of colorectal cancer than the general population. To improve early colorectal cancer detection, patients with a ten-year history of extensive colonic IBD are recommended to undergo colonoscopy surveillance at least every two years. Emmanuelle D. Williams, M.D., Penn State Milton S. Hershey Medical Center explains, “Currently recommended surveillance techniques (at least thirty-three random biopsies obtained from the entire extent of the colon) for IBD patients are time consuming and limited by a relatively low colorectal cancer detection rate where up to 25 percent of precancerous lesions are missed. Part of the challenge is the difficulty in visualizing pre-cancerous lesions in IBD patients because they can be multiple and flat with subtle irregularities rather than polypoid.” Chromoendoscopy, a technique that uses dye to highlight dysplastic tissue in existence since the 1970s, was introduced to IBD surveillance in 2003, and has since proven to markedly increase dysplastic lesion detection. While simple and inexpensive to do, Williams notes, “The technique requires training and practice, and additional time needed for obtaining dye-targeted biopsies and thus is typically only offered in tertiary care settings.”
Functional gastrointestinal (GI) motility disorders, including functional dyspepsia, are very common, often chronic, and disabling conditions that account for a large proportion of consultations with primary care and specialist physicians. Despite the absence of anatomical GI abnormalities, patients with functional GI disorders suffer with varying bouts of unexplained pain, cramping, diarrhea, vomiting, and constipation.
R. Alberto Travagli, Ph.D.
The research laboratories of R. Alberto Travagli, Ph.D., and Kirsteen Browning, Ph.D., of Penn State Hershey Neural and Behavioral Sciences, focus on describing the pathophysiology of these disorders. Travagli and Browning have recently conducted a series of in vitro and in vivo experiments (in collaboration with Gregory Holmes, Ph.D.) designed to better describe the role of stress in causing the gastroparesis that often occurs in such disorders. Evidence from these experiments,
Kirsteen Browning, Ph.D.
as well as from other laboratories, points toward stress related re-organization of the vagal sensory-motor loop connecting the gut to the central nervous system (CNS). The efferent limb of this reflex loop involves preganglionic parasympathetic neurons in the dorsal motor nucleus of the vagus (DMV), which provide the vagal output back to the GI tract. DMV neurons innervate postganglionic neurons located within the GI tract which belong to one of two distinct pathways; one is an excitatory pathway that increases gastric tone, motility and secretion via activation of muscarinic cholinergic receptors. The other is an inhibitory pathway that inhibits gastric functions mainly by releasing nitric oxide or vasoactive intestinal polypeptide. Continue reading