Dumping syndrome (DS) can be classified as early dumping syndrome (EDS) or late dumping syndrome (LDS) based on the timing of the symptoms after eating. It is a condition that is seen in up to 20% of individuals who undergo gastric, bariatric or esophageal surgeries.

The rapid emptying of largely undigested food particles into the small intestines may lead to a host of complications including nausea, diarrhea, abdominal pain, hypoglycemia, tachyarrhythmia and disturbances in consciousness.

The diagnosis of both EDS and LDS is a dilemma as it involves taking into account the signs and symptoms that can be elicited after testing a patient with oral glucose, sensitive hydrogen breath tests, and endoscopy or barium swallow studies to discern the anatomy of the gastrointestinal (GI) tract. Laboratory studies are rarely, if ever, helpful in establishing a diagnosis of DS. However, possible laboratory findings can be obtained from biochemical panels. Anemia and decreased albumin levels may be discovered in patients who are malnourished.

Diagnostic Scoring System

The Sigstad’s diagnostic scoring system for DS is very helpful in the monitoring of a patient’s response to therapy. It takes into account several parameters:

Numerical values are allocated to each of the Sigstad scoring criteria and a score that is greater than 7 is highly suggestive of DS.

Oral Glucose Provocation and Hydrogen Breath Tests

If the diagnosis of DS is dubious then oral glucose and hydrogen breath tests come in very handy as they have 100% sensitivity and 92% specificity. EDS symptoms can be triggered with the help of an oral glucose challenge - an increase in heart rate by 10 bpm or more following the administration of 50 grams of oral glucose after a 10-hour fast is considered diagnostic.

While the oral glucose challenge test is superb, it should be noted that higher amounts of glucose (i.e. more than 50 grams) should be avoided because this can cause symptoms in persons who are not actual patients. Positive breath tests for hydrogen are also 100% sensitive for EDS. LDS diagnosis can be done with the help of sampling the blood after an oral glucose challenge test. Elevated plasma levels of glucose in the first hour and reduced levels of plasma glucose within 1 to 2 hours later are expected.

Imaging

The evaluation of the upper GI tract is imperative to confirm LDS because there are other conditions that may produce similar symptoms. Hence, endoscopy or barium may be used for this purpose. In barium fluoroscopy, barium contrast is ingested and X-ray images are then taken. EDS is characteristically recognized by premature transition of the contrast medium out of the stomach. Radionuclide scintigraphy may also be done, in which a medium containing radionuclide is ingested and resultant gamma photons are detected by a gamma camera and the results are plotted on a graph against time. The rapid gastric emptying associated with DS is illustrated by steep drops in the activity plots of the graph.  

References

• https://med.virginia.edu/ginutrition/wp-content/uploads/sites/199/2015/11/UklejaArticle-Feb-06.pdf
• https://www.niddk.nih.gov/health-information/health-topics/digestive-diseases/dumping-syndrome/Pages/facts.aspx
• http://www.ncbi.nlm.nih.gov/pubmed/19724252
• https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentTypeID=134&ContentID=107