Most published literature describes gastroparesis as delayed gastric emptying without a mechanical obstruction.
At The Children’s Hospital of Philadelphia, our definition of gastroparesis is stricter. We consider gastroparesis to be a gastrointestinal (GI) motility disorder when there is objective delay in gastric emptying in the absence of any of the following:
The “gold standard” for diagnosing gastroparesis is scintigraphy, a diagnostic test that measures the rate of emptying a standard radio-labeled solid meal over a defined period of time. In infants and small children, milk is used as the test meal.
Symptoms of gastroparesis mirror some symptoms of delayed gastric emptying and include:
These symptoms, however, are non-specific and do not distinguish gastroparesis from a mechanical, infectious or non-infectious inflammatory or biochemical disorders that also cause delayed gastric emptying.
To make diagnosing GI disorders even more challenging, these same symptoms may also occur in patients with normal gastric emptying, the degree of delay in gastric emptying does not predict symptom severity, and correlation between symptom reductions and improved emptying cannot be always demonstrated.
The term gastroparesis is ambiguous because it implies a specific condition — paralysis of the stomach — without addressing causes or severity.
The exact cause of gastroparesis is unknown. The stomach is not paralyzed. Instead, gastroparesis seems to be both a muscle and sensory problem (neuromuscular disorder).
Factors that may contribute to gastrointestinal symptoms include: antral hypomotility, gastric dysrhythmia, impaired gastric fundic accommodation, antral distention, visceral hypersensitivity and psychological disturbance.
In children, gastroparesis may be an acute primary self-limiting disorder triggered by infection, surgery or excessive weight loss.
More commonly, however, pediatric gastroparesis overlaps in an individual patient with other chronic GI motility disorders including:
At the Suzi and Scott Lustgarten Center for GI Motility at CHOP, expert radiologists perform gastric emptying scintigraphy to evaluate patients with symptoms that suggest an alteration of gastric emptying. After radio-labeling the solid or liquid component of a meal, the gastric counts measured by scintigraphy correlate directly with the volume of test meal remaining in the stomach.
Unfortunately, at this time, there is lack of national standardization of test protocol for pediatric patients. Techniques vary in hospitals regarding size or volume of the test meal used, patient positioning, frequency and duration of monitoring.
Additionally, there are differences between hospitals about how the quantitative data is reported. Hospitals may measure any of the following:
In pediatrics, normal values have not been established for the protocols used. A standard practice at many hospitals has been to use adult normal values or to develop institutional norms developed from sub-populations of the patients studied.
At CHOP, our Nuclear Medicine Department works in conjunction with gastroenterologists and other specialists to use best practices in testing pediatric patients.
A child receiving a scintigraphy will eat a radio-labeled egg (equivalent to two large eggs), bread or toast, and water as the solid test meal. Then, clinicians will measure the child’s percentage of gastric emptying at 30, 60, 90, and 120 minutes after the meal. Measurement is done with a gamma camera placed on the child's chest and abdomen to picture the perfused organs.
Patients are categorized as having delayed gastric emptying if emptying of the meal is less than 10 percent at 60 minutes or less than 50 percent at two hours post meal. These criteria are less strict than adult consensus guidelines established by the American Motility and Nuclear Medicine Society where two-hour emptying is considered delayed if less than 40 percent of the meal empties at 120 minutes.
Although adult studies have shown that extending measurements out to four hours increases the detection rate of delayed emptying in patients who appear normal at two hours, we feel our less stringent criteria at two hours will pick up this subgroup, and thus, reserve four-hour studies for patients with late postprandial symptoms.
Factors that must be considered in interpretation of test results include:
Since population studies have shown a poor correlation between a rate of solid gastric emptying and the severity of gastric symptoms, we basically use the scintigraphy test to classify patients as having objective evidence of delayed gastric emptying.
In addition to gastroparesis, causes of delayed gastric emptying include:
At The Children's Hospital of Philadelphia, we offer expert clinicians and a full spectrum of diagnostic tests for gastrointestinal motility disorders at the Lustgarten Center for GI Motility. The Lustgarten Center provides diagnostic resources and integrated patient-centered services that are not available at most children's hospitals.
Before a definitive diagnosis of gastroparesis can be reached, physicians must rule out the possibility that other mechanical, infectious or non-infectious inflammatory and biochemical reasons are causing the delayed gastric emptying.
At the Lustgarten Center, our clinicians gather a comprehensive family history, perform a physical exam and schedule diagnostic tests for each pediatric patient with a suspected gastroparesis diagnosis. The following are common diagnostic tests:
Under the careful supervision of a radiologist, the child drinks a barium liquid that coats the upper GI tract, illuminating the flow of the liquid through the esophagus, stomach and duodenum.
This test rules out mechanical causes of delayed gastric emptying including gastric outlet obstruction, malrotation and partial small bowel obstruction.
The upper endoscopy allows the doctor to use an endoscope (a long, thin tube) to look at the lining of the stomach and proximal small bowel to confirm absence of mechanical obstruction, but also exclude infectious and inflammatory causes of delayed gastric emptying.
This test can rule out H. Pylori gastritis, peptic ulcer, reactive gastritis, eosinophilic gastroenteritis, celiac disease and upper GI Crohn’s disease.
Biochemical tests rule out correctable electrolyte and balance, renal function and endocrine status.
A diagnosis of gastroparesis is established if upper GI series and endoscopy of the stomach and duodenum are normal, and biochemical testing rules our correctable electrolyte or metabolic disorder.
Left untreated, gastroparesis can have a significant negative impact on a child's life. Some complications include:
Gastroparesis is a very challenging disorder for pediatric gastroenterologists to treat. At present there is no standardized medical therapy for gastroparesis. Therapy must be individualized, and include dietary management, pharmacologic therapy and non-pharmacologic therapy.
At CHOP's Lustgarten Center for GI Motility, therapy generally follows a step-up symptom-based protocol that is related to symptom severity and degree of disability, not to the degree of abnormal emptying. Our clinicians provide a multidisciplinary, patient-centered approach to care. We will coordinate with your child's primary care physician and other specialists to ensure the best management of the disease, and provide long-term follow-up care for your child.
Our ultimate goal is to help your child live as healthy, active and comfortable a life as possible.
Nutritional management of gastroparesis is based on the understanding of normal stomach emptying. Treatment approaches will vary based upon the severity of the disease and the patient’s nutritional status.
The goals of nutritional management are to ensure adequate calories, and that nutrients are consumed to promote your child’s growth and development. Maintaining a healthy diet can help control the symptoms of gastroparesis.
Dietary changes are tailored to each patient and may include:
For children with severe nausea, vomiting and significant weight loss, placement of a nasogastric, nasojejunal or gastrostomy tube may become necessary to ensure adequate hydration and adequate daily caloric intake.
A venting gastrostomy may reduce nausea and vomiting allowing the patient to increase daily oral caloric intake
Rarely, patients with severe nausea, vomiting and weight loss may be unable to tolerate nutrients in gastric and small bowel feedings. These patients require central intravenous hyperalimentation.
Although there is no cure for gastroparesis, the focus of pharmacological therapy is to improve patient lifestyle by attempting to improve gastric emptying, and targeting symptoms such as nausea, vomiting, abdominal bloating and abdominal pain. A combination of medications is often used in individual patients. Each medication affects patients differently and a combination that may benefit one individual may not benefit another.
All of the above therapies currently have minimal to modest effect on gastric emptying which suggests that their effect on symptoms of gastroparesis may be mediated by a different mechanism.
At the Lustgarten Center for GI Motility, children and their families also benefit from the support of child psychologists who work with CHOP’s GI motility patients to help them better manage their symptoms.
Psychological therapies such as stress management, cognitive behavioral therapy, relaxation therapy and biofeedback give children other ways to minimize the negative impacts of their disease on their quality of life. The involvement of a child psychologist is an integral part of the treatment plan.
In general, the overall goal of gastroparesis treatment is to help the patient achieve a healthier lifestyle by using a combination of nutritional, pharmacological and non-pharmacological therapies.
Reviewed by: John T. Boyle, MD, and Kristin N. Fiorino, MD
Date: October 2012