A rapid, single-step, in-laboratory qualitative test for the detection of IgG antibodies to Helicobacter pylori in serum (TestPack Plus; Abbott Laboratories, Germany) was evaluated. This test may be used as an alternative to enzyme immunoassays (EIAs). Of 153 adult patients, 110 were defined as Helicobacter pylori positive and 43 as Helicobacter pylori negative by the gold standard, a combination of three tests. The performance characteristics of the TestPack Plus, i.e. sensitivity, specificity, and positive and negative predictive values, were not significantly different from the corresponding values obtained with an EIA used for comparative purposes, the Pyloriset EIA-G test (Orion Diagnostica, Finland). The high positive predictive value (93%) of the TestPack Plus single-step serological test makes it a valuable tool for rapid in-laboratory screening purposes, especially in countries with a high prevalence of Helicobacter pylori infection.