[The resistance of the bacterial flora in cancer patients to drug therapy].

Agents etiologically relevant to hospital infection have been studied in an oncologic clinic for the period of 20 years since 1969. Pronounced changes in the profile of basic infections have been observed. In 1969, Staphylococcus accounted for 46% of cases of infection and E. coli was isolated in 22% whereas in 1987 and 1988, the respective figures for staphylococcus were 18 and 16% only while for E. coli--8.4 and 8.6%, respectively. At the same time, the occurrence of all types of streptococcal infections has risen from 17 to 26-27%. As regards gram-negative bacilli such as Klebsiella spp., Ps. aeruginosa, Enterobacter, Acinetobacter and Serrata spp., their share has increased and spectrum has become wider. The level and spectrum of drug resistance have changed, too. The level of plasmid genes accounting for resistance and pathogenicity in bacterial genomes, particularly, in gram-negative bacilli, have increased. Formation of multidrug resistant strains was shown to depend both on intensity of drug treatment in the clinic and presence and activity of R plasmids, particularly, with a wide spectrum of hosts.