INTERACTION BETWEEN ANTIBIOTICS AND ANTINEOPLASTIC DRUGS ON ANTIBACTERIAL ACTIVITY IN-VITRO - ESTRAMUSTINE PHOSPHATE SENSITIZES PNEUMOCOCCITO AMIKACIN

The antibacterial and interactive effects of doxorubicin, cisplatin, c ytarabine, vincristine, carmustine, mitoxantrone, methotrexate, bleomy cin, 5-fluorouracil, epirubicin, DTIC, mitomycin, etoposide and estram ustine phosphate on the antibacterial activity of penicillin G, pipera cillin, ceftazidime, imipenem, trimethoprim, amikacin, tetracyclin, ox acillin, metronidazole, 5-FC, and amphotericin B were studied on 57 ba cterial strains. The bacterial species investigated were Escherischia coli, Staphylococcus epidermidis, Staphylococcus aureus, Klebsiella pn eumoniae, Enterobacter cloacae, Pseudomonas aeruginosa, Streptococcus pneumoniae, and Bacteroides fragilis. The antineoplastic drugs were di luted in Muller-Hinton agar on which the bacteria were propagated. For the susceptibility tests standard antibiotic paper discs were used an d results were confirmed with the PDM epsilometer test. Seven of the f ourteen cytostatic agents displayed an intrinsic antibacterial effect. A most striking interactive effect was seen in the situation where es tramustine phosphate caused a marked increased sensitivity of pneumoco cci to amikacin, a drug to which they are regularly completely resista nt.