What to Expect When Being Evaluated for Gastroparesis
In honor of Gastroparesis Awareness Month, which is observed in August, this month’s What to Expect piece will detail the gastroparesis diagnostic process. My personal diagnostic process lasted about a year and involved several procedures. In this piece, I will provide a brief overview of some of the procedures commonly performed to diagnose gastroparesis. Because gastroparesis, which causes symptoms like nausea and vomiting, has significant symptom overlap with other digestive conditions, I will also address some of the procedures performed to rule out differential diagnoses.
Keep in mind that any diagnostic process is tailored by a doctor to meet the specific needs of the patient being evaluated. For this reason, some patients who are suspected of having gastroparesis may not need to undergo all of the procedures in this list. Some patients may need additional procedures that are not covered in this piece. Every hospital has its own way of administering each procedure, so some of the procedures described here may be performed differently at other hospitals.
To make a definitive diagnosis of gastroparesis, your doctor will likely have you complete a Gastric Emptying Study.
A procedure known as the Gastric Emptying Study is widely considered to be the “gold standard” in diagnosing gastroparesis. This procedure determines how quickly the stomach empties itself of food. Gastroparesis, also known as delayed gastric emptying, is characterized by slower emptying of food from the stomach than is normal. A differential diagnosis that can also be made using the Gastric Emptying Study is dumping syndrome. This condition, which shares some symptoms with gastroparesis, is characterized by faster than normal emptying of food from the stomach. A gastric emptying study is capable of diagnosing either of these conditions.
Before undergoing a gastric emptying study, the patient will usually be instructed to fast for a specified amount of hours prior to the procedure. Your doctor may also instruct you to discontinue certain medications before the procedure. When performing a Gastric Emptying Study, a technician will have the patient eat a predetermined quantity of food. This food, which usually consists of eggs and toast, is laced with a small amount of radioactive material. Images will be taken over the course of the study to track the movement of the radioactive food from the stomach to the small intestine. A radiologist will be able to use these images to determine the rate that food empties the stomach. Gastroparesis is usually diagnosed when at least 10% of the radioactive food is observed to remain in the stomach after four hours.
In addition to a Gastric Emptying Study, your doctor will likely have you undergo an Upper Endoscopy to rule out blockages.
Gastroparesis is specifically defined as delayed gastric emptying in the absence of an obstruction. In order to rule out a mechanical blockage that may be preventing food from leaving the stomach, doctors commonly perform an upper endoscopy. An upper endoscopy is a sedated procedure where a scope is inserted down the patient’s throat and into the stomach and the upper part of the small intestine. The scope has a camera that allows the doctor to look for any inflammation, ulceration, or tissue damage that may be present. The scope is also capable of taking small tissue samples that can later be analyzed by the hospital lab. An upper endoscopy is capable of diagnosing many conditions that share symptoms with gastroparesis, such as Crohn’s disease, celiac disease, gastritis, eosinophilic esophagitis, and mechanical obstructions.
If your doctor is concerned about the motility in your esophagus, you may be prescribed an Esophageal Manometry.
An esophageal manometry is a procedure used to diagnose motility disorders of the esophagus, such as achalasia, esophageal hypomotility, and esophageal spasms. During this procedure, a pressure-sensing probe is inserted through the nose and down the esophagus. The probe is capable of measuring the muscular activity in the esophagus that occurs when the patient swallows. The test will be able to identify if liquid gets stuck in the esophagus when the patient tries to swallow and whether or not the patient’s esophagus contracts with the proper amount of force. You can read more about what to expect during an esophageal manometry here.
If you experience significant acid reflux, you may need to undergo a 24-hour pH probing procedure.
The 24-hour pH probing procedure is considered the “gold standard” in diagnosing acid reflux disease, also known as GERD. This procedure, which is usually performed after an esophageal manometry, measures the acid levels within a patient’s esophagus during a 24-hour period. The 24-hour pH test requires inserting a probe into the patient’s nose and down the esophagus. The probe used in this procedure, however, is thinner than the probe used during an esophageal manometry. After the probe is inserted, the patient is instructed to go throughout their day normally. You can read more about this procedure here.
If your doctor suspects that you may have issues with the functioning of your lower digestive tract, you may have to undergo an anorectal manometry and/or a sitz marker test.
Many patients with gastroparesis also have problems with the motility of the lower digestive tract. Some of these problems include chronic constipation, pelvic floor dysfunction, and colonic inertia. If a patient has a significant amount of lower digestive tract symptoms, an anorectal manometry or a sitz marker test may be performed. I have personally undergone an anorectal manometry, but I have not had a sitz marker test done. During an anorectal manometry, a pressure-sensing probe is inserted into the rectrum to test the functionality of the muscles of the pelvic floor. This test is able to diagnose different types of pelvic floor dysfunction.
I hope this piece provided useful information about the gastroparesis diagnostic process. Like many digestive disorders, gastroparesis can be difficult to diagnose. It is common for a gastroparesis patient to have undergone several procedures before receiving a diagnosis. Because the symptoms of gastroparesis, such as nausea and vomiting, are shared by many other digestive conditions, differential diagnoses must be ruled out. Good luck if you are personally going through the diagnostic process.
I hope this information helps,