Intravenous Calcium Injection Test Is a Novel Complementary Procedure in Differential Diagnosis for Gastrinoma

Intravenous Calcium Injection Test Is a Novel Complementary Procedure in Differential Diagnosis for Gastrinoma

Abstract

Abstract

The current study evaluated efficacy of

the intravenous calcium injection test as a new diagnostic approach to

clarify the existence of gastrinoma, which often goes undetected with

routine testing. Twenty-six patients with hypergastrinemia were

studied. For the calcium injection test, blood samples were taken from

12 patients with hypergastrinemia (HG), and three healthy volunteers,

and one patient with nonfunctioning endocrine tumor in the pancreas

(control). We compared results of the calcium injection test with those

of the secretin test and the selective arterial secretagogue injection

(SASI) test. The SASI test with secretin was performed in 24 of 26

patients with hypergastrinemia, including 22 of 24 patients with

Zollinger-Ellison syndrome (ZES). Accuracy in the diagnosis of tumor

localization by the SASI test was 95% (21 of 22) in ZES patients. The

secretin test was negative in 3 of 21 patients with ZES (14%). Either

the secretin test or the SASI test was positive in 22 of 23 patients

(96%). The calcium injection test was administered to 12 patients in

the HG group and 4 controls. The HG group showed significantly higher

serum gastrin levels than those of the control group in the calcium

injection test. Eight of 10 ZES patients (80%) had a positive calcium

injection test. We could diagnose gastrinomas in 100% of ZES patients

by either the calcium injection test or the secretin test. We have thus

confirmed the efficacy of the intravenous calcium injection test in the

diagnosis of gastrinoma. The calcium injection test could become an

adjunct in the diagnosis of gastrinoma, which often goes undetected

with routine testing.