Background: The diagnosis – and hence definitions – of healthcare-associated infections (HAIs) rely on microbiological laboratory test results in specific constellations.

Objectives: To construct a library that provides interoperable building blocks for the analysis of microbiological laboratory test results.

Methods: We used Java for preprocessing raw microbiological laboratory test results and Arden Syntax for knowledge-based querying of data based on microbiology information elements used in European surveillance criteria for HAIs. To test the library and quantify how often these information elements occur in the data, we performed a retrospective cohort study on adult patients admitted for at least 24 hours to an intensive care unit at the Vienna General Hospital in 2013.

Results: We identified eleven information elements for which information was electronically available. These elements were identified positively 1,239 times in 1,184 positive microbiology tests from 563 patients.

Discussion: The availability of a library for the analysis of microbiology laboratory test results in HAI terms facilitates electronic HAI surveillance.