Hypothesis: Endosonography (EUS) in a single setting is equivalent to the standard algorithm combining abdominal sonography, gastroscopy, endosonography in patients with acute right side abdominal pain.

Patients with acute right side abdominal pain will be randomized in one of two groups. In each group all examinations (sonography, gastroscopy, endosonography) will be performed. The study group only defines the order of the examinations. Abdominal sonography will always be performed before endoscopic procedures. In group 1, gastroscopy is first followed by endosonography. In group 2 endosonography is first followed by gastroscopy.

Two physicians will review all results of all examinations, patient charts as well as a follow up visit and establish a clinical diagnosis.

Yield of the clinical diagnosis by EUS results alone will be compared to the yield by combined results of sonography, EGD and EUS.

Inclusion Criteria:

• acute right side abdominal pain
• willing participate study

Exclusion Criteria:

• acute disease
• malignancy
• other disease which might cause discomfort