[Toxoplasmosis diagnosis in pregnancy: computer assisted follow-up interpretation of serologic tests]

Primary infection with Toxoplasma gondii during pregnancy can result in fetal infection with serious sequelae for the unborn if not treated properly. Early diagnosis enables drug therapy and significantly reduces the risk of fetal disease. A systematic serological screening procedure was established in Austria in 1975 to detect primary toxoplasma infection as early as possible during pregnancy. Since the screening program is based solely on observation and interpretation of serological data, the question arises whether a knowledge-based system for automatic interpretation can achieve a sufficient interpretative accuracy for introduction to routine work. For this reason the system Toxopert-I was developed. The system is aimed at facilitating routine laboratory work, as well as assuring quality by setting standards for therapy. The required knowledge base was designed as a knowledge graph, each state representing a certain interpretation. One or more available serological test results cause the knowledge graph to change its current state. If all available test results are processed, the final state reached corresponds to the respective current interpretation for the patient. A retrospective analysis of 1000 pregnant women yielded a total diagnostic sensitivity and specificity of over 99% in comparison with the clinician's diagnosis which was used as the Gold Standard.