OBJECTIVES: The aim of the study was to analyse the diagnostic performance of the basophil activation test (BAT), to compare the diagnostic reliability of BATs performed with different types of allergens, which are available in Slovakia and to verify the correlation between the symptom severity and the sensitivity and specifi city of the BAT in 114 patients with suspected hymenoptera venom allergy (HVA). BACKGROUND: Diagnosis of the HVA and the identifi cation of the appropriate venom for immunotherapy are in Slovakia based on detailed patient'medical history, skin tests and detection of sIgE. In unclear cases, where the clinical decision regarding the relevant insect species for immunotherapy is diffi cult, the cellular tests are recommended in several countries, such as Sweden, Spain, Germany, Denmark and Italy. In Slovakia, BAT is not adapted as s part of routine diagnostic work-up. METHODS: The identifi cation of the culprit hymenoptera species among 114 patients was based on detailed history, skin tests and detection of sIgE. Obtained results were compared with the results acquired by the BAT. RESULTS: The sensitivity of the BAT was 80.8 % and the specifi city was 87.8 %. The sensitivity of the BAT was higher when using Soluprick SQ Allergens, but the specifi city was higher with BŰHLMANN CAST Allergens. In the study no correlation between the symptom severity and the sensitivity and specifi city of the BAT was observed. CONCLUSIONS: The results show that the BAT can be recommended in the identifi cation of the appropriate venom for immunotherapy, the only specifi c treatment that is currently available for patients with HVA. Allergen source is one of critical factors in diagnostic reliability of the BAT (Tab. 4, Ref. 29).