[Effect of gentiana violet against methicillin-resistant Staphylococcus aureus (MRSA)].

The bactericidal effect of gentiana violet against MRSA isolated from clinical specimens was studied both in vitro and in vivo. The results obtained are as follows: 1) Minimum bactericidal concentration (MBC) of gentiana violet to MRSA was between 0.0025% and 0.08% and the MBC was not influenced even if 25% human whole serum exists in the medium. 2) The number of cells were 2.1 x 10(7) CFU/ml in medium which decreased to 5.4 x 10(4) CFU/ml within 5 min by existing 0.1% gentiana violet in the medium as the final concentration, and also decreased under 10(3) CFU/ml 15 min later. 3) Minimum inhibitory concentration (MIC) of gentiana violet to MRSA was between 0.00015% and 0.00063%, and the inhibitory activity was not influenced even if gentiana violet was incubated with the bacteria in the medium for 72 hr at 37 degrees C. 4) By using an ointment containing 0.1% gentiana violet to 12 cases of patients with the MRSA infected skin lesions, MRSA was eliminated completely from the infected areas of the skin within 4 weeks. 5) The side effects of gentiana violet were not observed in all cases during the use of the ointment containing gentiana violet. It is suggested that gentiana violet may be one of the useful drugs for the treatment of the skin lesions infected with MRSA.