[Comparison of manual agar-diffusion (Bauer) technique and "Abac" semiautomatic device for the determination of "in vitro" bacterial sensitivity to antibiotics (author's transl)].

A comparison of antibiotic in vitro sensitivity tests performed on 115 freshly isolated Gram-negative bacterial strains with the manual standardized agar-diffusion technique according to Bauer and with the semiautomatic Abac (Intertechnique) device showed univocal results 85.5% of times, being Abac sensitivity 85.6% and specificity 86.2%. The frequency of univocal results is higher that in most of the previous trials, especially for ampicillin and cephalotin. No particular responses have been shown by the dirrerent microorganisms tested. After a discussion of the variables which can influence the results and the suggestion of some steps to be taken, the AA. analyze the role of Abac and its possible achievements in small and medium-size bacteriological laboratories.