EUS compared with endoscopy plus transabdominal US in the initial diagnostic evaluation of patients with upper abdominal pain

Background: Primary upper endoscopy (EGD) and transabdominal US (TUS) are often performed in patients with upper abdominal pain. Objective: Primary: Determine whether the combination of EGD and EUS was equivalent to EGD plus TUS in the diagnostic evaluation of upper abdominal pain. Secondary: Compare EUS versus TUS in detecting abdominal lesions, and compare EGD by using an oblique-viewing echoendoscope versus the standard, forward-viewing endoscope in detecting mucosal lesions. Design: Prospective, paired design. Setting: Six academic endoscopy centers. Patients: This study involved patients with upper abdominal pain referred for endoscopy. Intervention: All patients had EGD, EUS, and TUS. The EGD was done using both an oblique-viewing echoendoscope and the standard, forward-viewing endoscope (randomized order) by two separate endoscopists in a blinded fashion, followed by EUS. TUS was performed within 4 weeks of EGD/EUS, also in a blinded fashion. Follow-up: telephone interviews and chart reviews. Main Outcome Measurements: Diagnose possible etiology of upper abdominal pain and detect clinically significant lesions. Results: A diagnosis of the etiology of upper abdominal pain was made in 66 of 172 patients (38%). The diagnostic rate was 42 of 66 patients (64%) for EGD plus EUS versus 41 of 66 patients (62%) for EGD plus TUS, which was statistically equivalent (McNemar test; P = .27). One hundred ninety-eight lesions were diagnosed with either EUS or TUS. EUS was superior to TUS for visualizing the pancreas (P < .0001) and for diagnosing chronic pancreatitis (P = .03). Two biliary stones were detected only by EUS. Two hundred fifty-one mucosal lesions were similarly diagnosed with EGD with either the standard, forward-viewing endoscope or the oblique-viewing echoendoscope (kappa = 0.48 [95% CI,.43-.54]). EGD with the standard, forward-viewing endoscope was preferred for biopsies. Limitations: No cost analysis. Conclusion: The combination of EGD with EUS is equivalent to EGD plus TUS for diagnosing a potential etiology of upper abdominal pain. EUS is superior to TUS for detecting chronic pancreatitis. EGD combined with EUS should be considered in the first-line diagnostic evaluation of patients with upper abdominal pain. (Gastrointest Endosc 2010;72:967-74.)