Resolution or improvement of symptoms on this course may result in a diagnosis of GERD.Other tests or symptoms suggesting acid reflux is causing heartburn include:

Onset of symptoms after eating or drinking, at night, and/or with pregnancy, and improvement with PPIs
Endoscopy looking for erosive changes of the esophagus consistent with prolonged acid exposure (e.g. - Barretts esophagus)
Upper GI series looking for the presence of acid reflux

GI cocktail
Relief of symptoms 5 to 10 minutes after the administration of viscous lidocaine and an antacid increases the suspicion that the pain is esophageal in origin. This however does not rule out a potential cardiac cause as 10% of cases of discomfort due to cardiac causes are improved with antacids. Biochemical
Esophageal pH monitoring: a probe can be placed via the nose into the esophagus to record the level of acidity in the lower esophagus. Because some degree of variation in acidity is normal, and small reflux events are relatively common, esophageal pH monitoring can be used to document reflux in real-time. Patients are able to record symptom onset to correlate lower esophageal pH with time of symptom onset. Mechanical
Manometry: in this test, a pressure sensor (manometer) is passed via the mouth into the esophagus and measures the pressure of the LES directly.Endoscopy: the esophageal mucosa can be visualized directly by passing a thin, lighted tube with a tiny camera known as an endoscope attached through the mouth to examine the oesophagus and stomach. In this way, evidence of esophageal inflammation can be detected, and biopsies taken if necessary.
The trials were conducted in the United States and Canada.Trial 1 enrolled subjects 1 to 20 years old who were recently diagnosed with ALL or lymphoblastic lymphoma. Subjects received calaspargase pegol-mknl or pegaspargase (a drug that helps convert asparagine to other substances) as part of a combination of drugs used for treatment of ALL. The trial had 2 phases. Subjects received calaspargase pegol-mknl or pegaspagase intravenously on Day 7 of the first phase. Subjects received either calaspargase pegol-mknl intravenously every 3 weeks for 10 doses or pegaspargase intravenously every 2 weeks for 15 doses during the second phase. The benefit of calaspargase pegol-mknl was assessed by measuring the activity level of asparginase in the blood on Days 7, 11, 18, 25, and 32 of the first phase and comparing it to pegaspargase.Trial 2 enrolled subjects 1 to 18 years old who were recently diagnosed with high-risk ALL. Subjects received one of 2 doses of calaspargase pegol-mknl or pegaspargase intravenously as part of a combination of drugs used for treatment. Subjects received calaspargase pegol-mknl or pegaspargase on Day 4 of the first phase and Days 2 and 22 of the second phase. Subjects received up to 12 doses of calaspargase pegol-mknl or pegaspargase intravenously depending on the bone marrow response. The benefit of calaspargase pegol-mknl was assessed by measuring the concentration of drug in the body over 25 days (AUC) and the maximum amount of drug in the blood after a single dose (Cmax).