<原著>数種の二次抗結核剤の毎日投与法と間歇投与法との効果比較に関する試験管内実験

Abstract

Experimental studies were performed in vitro with a silicone-coated slide culture method on minimum inhibitory concentration, minimum sterilizing concentration and development of drug resistance in an attempt to determine the effect of daily and of intermittent (twice weekly) chemotherapeutic regimens with kanamycin (KM), cycloserine (CS), ethambutol (EB) and ethionamide (TH). The following results were obtained. (1) In growth-inhibiting activity against H37Rv, for every drug tested in this experiment, the continuous regimen was more effective than the intermittent one. (2) The bactericidal activities against H37Rv under these experimental conditions showed the inferiority of the intermittent to the continuous regimen. It was very difficult to sterilize tubercle bacilli by the intermittent action of CS, EB or TH even at the concentration as high as 1, 000mcg. per ml. (3) H37Rv did not develop drug-resistance to CS or EB under either regimen. Slight drug-resistance to KM and TH developed in the range of concentrations of incomplete sterilization. The range of incomplete sterilizating concentration under the intenmittent regimen was higher than that under the continuous regimen and such high concentrations can not be maintained in body fluids clinically. This may be the reason why a drug-resistance is unusual under the intermittent regimens. (4) The results of these experiments showed that an antituberculous regimen of twiceweekly administration is less effective than daily administration in every respect.