The Penn Neurogastroenterology and Motility Disorders Program was developed to apply clinical expertise, research, and technology to the diagnosis and management of esophageal (e.g., achalasia), gastric and intestinal motility disorders, and their physical and psychological effects.
Neurogastroenterology and GI motility disorders are the leading cause of visits to gastroenterologists across the United States.
What is a Motility Disorder?
Broadly defined, any alteration in the transit of gastrointestinal contents and secretions can be considered a motility disorder. Whatever the cause, the result is loss of coordinated muscular activity in the digestive system in a way that transit is either hastened or slowed. In addition to diarrhea, incontinence, and constipation, the manifestations of the motility disorders can include malnutrition, abdominal bloating, severe abdominal pain, gastroesophageal reflux, nausea, and intractable vomiting.
In addition to imposing a heavy burden of illness, the GI motility disorders are attended by decreased quality of life and work productivity, depression, weight loss and isolationism.
What Causes Motility Issues?
The management of GI motility disorders is underpinned by a thorough understanding of GI motility dysfunction.
Clinical understanding of the origin of the motility disorders has recently evolved to include both immune-mediated and neurogastrointestinal factors. Injury and infection have long been known to overwhelm gastrointestinal homeostasis.
In this rendering of motility pathology, exogenous factors cause the release of mediators from cellular sources in the gut wall, including amines, proteases, and cytokines that, acting on receptors in the nerve endings, elicit hypersensitivity to chemical and physical stimuli. Hypersensitivity interferes with the reflexes that coordinate gut function, leading to pain, maldigestion, vomiting, diarrhea, constipation and incontinence.
The Origins of Neurogastroenterology
The etiology of the intestinal motility disorders cannot be fully explained by physiological causes alone. As early as the 11th century, the philosopher Ibn Sina noted the effects of mental excitement and emotion on digestion, and a cursory review of medical literature in the ensuing centuries finds frequent reference to a connection between emotional status and gastrointestinal distress and disease.
Although the gut-brain axis was theorized as early as the 1880s, illuminating evidence for a connection between higher order neurological processes and the constitution of the GI tract began to accumulate in earnest only in the late 20th century among researchers in the evolving field of neurogastroenterology.
Today, the Rome Foundation—a primary force in the international effort to diagnose and treat the functional gastrointestinal disorders (FGIDs)—defines an FGID as the product of the interaction of psychosocial factors and altered gut physiology via the brain-gut. According to the Foundation’s biopsychosocial conceptual model, genetic composition and interactions with the environment and one’s own microbiome influence susceptibility to disease, phenotypic expression and, importantly, patient behaviors.
Further complicating the etiology of the motility disorders is their association with a number of primary disease states, including scleroderma, dysautonomia, Parkinson's disease, diabetes mellitus, Ehlers-Danlos’ syndrome, degenerative and endocrine disorders, cardiovascular disorders (e.g., stroke, tachycardia), spinal cord injuries, dementia and aging.
The Penn Neurogastroenterology and GI Motility Disorders Program
The Penn Neurogastroenterology and GI Motility Disorders Program (Penn NGIMD) was developed to diagnose and treat the severe manifestations of the intestinal motility disorders, including prolonged constipation (weeks, months), vomiting, weight loss, dysbiosis, distension, fecal incontinence, bacterial overgrowth of the small intestine, pseudo-obstruction, gastroparesis, and the complications of such rare disorders noted above, including Ehlers-Danlos Syndrome and postural orthostatic tachycardia.
The Program is led by renowned gastroenterologist James Reynolds, MD, Professor of Clinical Medicine.
Dr. Reynolds is joined at the Program by:
Nitin Ahuja, MD, a graduate of the University of Michigan Medical School. Dr. Ahuja completed an internship in internal medicine at the University of Virginia Medical Center, and was a Gastroenterology Fellow at Johns Hopkins University. An accomplished researcher, Dr. Ahuja specializes in esophageal disorders and their contribution to dysmotility.
Erin Toto, MD, is a graduate of Jefferson Medical College. She completed a residency in internal medicine at McGaw Medical Center of Northwestern University and a Fellowship in gastroenterology at Temple University School of Medicine. Board certified in internal medicine and gastroenterology, Dr. Toto has published on the effects of pregnancy and postpartum bowel changes on motility.
Hannah Ryan, CRNP, a full time CRNP (nurse practitioner) dedicated to the Neurogastroenterology and GI Motility program. Ms. Ryan received her education at Villanova and LaSalle University. She will see patients at PCAM. Ms. Ryan will assist also in clinical research, including a study of cognitive behavioral therapy in the management of the functional gastrointestinal diseases.
In addition to treating the immune-mediated, traumatic, and biological causes of the motility disorders, Penn Neurogastroenterology and GI Motility is involved with identifying and managing psychological and social contributors, including stress, anxiety and other neurological conditions.
A vital component of the Penn NGIMD Program’s mission involves research, particularly into the microbiome, in cooperation with the laboratories of Gary Wu, MD, and James Lewis, MD, MSCE. Clinical investigations now suggest an intricate and as yet little understood 'knotting' of the motility disorders, the FGIDs, human behaviors and the microbiome and its disruptions.
Diagnosing Motility Disorders
Accurate diagnosis of the GI motility disorders depends largely on clinical expertise and the availability of technologies capable of distinguishing and interpreting the function and responsiveness of the nervous system of the lower intestine and bowel. Thus, at Penn, the technologies available include high-resolution esophageal and high-resolution anorectal manometry, endoscopy, fluoroscopic and radiological imaging, gastrointestinal scintigraphy, single-photon emission computerized tomography (SPECT), and pelvic floor MRI. A new, non-invasive technology to evaluate gastric, small bowel, and colonic motility using capsule technology has been acquired recently.
A variety of investigative assessments are also being developed at Penn, including provocation tests (i.e., meal, intracolonic balloon distension) and rectal sensation, tone, and compliance tests (See Table 1).
Penn NGIMD also has the mission of diagnosing and treating gastroparesis, intestinal pseudo-obstruction, and other complex motility disorders. These motility disorders are defined as persistent or recurrent dysmotility (abnormal visceral muscle activity manifesting as slow bowel transit or delayed gastric emptying). A recognized effect of diabetes, gastroparesis may be caused by damage to the vagus nerve, the enteric nerves, or both. The causes of pseudo-obstruction are obscure, but in most patients, a neural origin is suspected, as well.
Diagnostic and Treatment Tools for Patients with Neurogastroenterologic and Motility Concerns
- 3-Dimensional high resolution anorectal manometry with biofeedback
- Capsule motility/endoscopy of stomach, small bowel & colon
- High Resolution Esophageal Manometry
- Esophageal Impedance/pH Evaluations
- Esophageal 48 hour pHmetry
- Breath Testing (lactulose, fructose & sucrose)
- Colorectal Surgery
- General Surgery
- Gastric Pacemaker Placement
- Sacral Nerve Stimulator Placement
- Fluoroscopic Defecography
- MRI Defecography
- MR & CT Enterography
- Radionuclide Gastric Emptying & Whole Gut Transit Study
- Psychiatric Consultation
- Cognitive Behavioral Therapy
- Nutritional Support (TPN & TEN)
- Interventional Radiology Devices
- Pelvic Floor Physical Therapy
How is a Motility Disorder Treated?
Treatment for the motility disorders at Penn has the purpose of improving the symptoms of dysmotility, resolving the cause (if possible), and enhancing patient quality of life, sense of well-being, and capacity to engage in everyday activities.
A diverse spectrum of treatment is available to the patient with motility disorders at Penn, ranging from dietary management and psychiatric interventions (including cognitive behavioral therapy), to drug therapy (parasympathomimetics, prokinetic agents, and antidiarrheals), gastric and sacral nerve stimulators, and in rare instances, surgery.
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