[Laboratory and clinical studies of 9,3"-diacetylmidecamycin in the pediatric field].

The authors have carried out laboratory and clinical studies of 9,3"-diacetylmidecamycin (MOM) and obtained the following results. 1. Absorption and excretion of MOM. MOM was administered orally to 4 patients at a dose of 10 mg/kg in the fasting condition. The peak of serum levels was found at 30 minutes after administration. The mean values were 1.3 +/- 0.5 microgram/ml, and 1.1 +/- 0.9 microgram/ml after 30 minutes and 1 hour respectively. The serum levels were detectable in 2 cases after 2 hours (1.0 and 0.78 microgram/ml), in 1 case after 4 hours (0.78 microgram/ml) and were not detectable in all cases after 6 hours. Half-life was able to calculate in 2 cases (2.5 and 1.5 hours). The mean urinary recovery rate examined in 3 cases was 0.33% for initial 6 hours. 2. Clinical result. MOM was administered to 35 children at a daily dose of 16.7--51.1 mg/kg divided into 3 or 4 doses for 4 to 19 days: 18 cases with bacterial infection (9 cases with tonsillitis, 7 cases with scarlet fever and each 1 case with bronchitis and pneumonia) and 17 cases with Mycoplasma infection (5 cases with bronchitis and 12 cases with pneumonia). The overall clinical response was good in 28 cases (80.0%), fair in 6 cases and poor in 1 case. The efficacy rate in bacterial infections and Mycoplasma infections were 66.7 and 94.1% respectively. Eight strains of S. pyogenes and 1 strain of S. pneumoniae were isolated from 9 cases. One strain of S. pyrogenes was eradicated and the others were unchanged. The eradication rate was 11.1%. The MIC of MOM against S. pyogenes was above 50 micrograms/ml in 3 strains out of measured 5 isolated strains. 3. Side effect. Side effects were examined with all the 54 cases involving 19 drop-out cases. Although clinical side effects were not observed, a mild elevation in GOT and a mild rise in eosinophil were observed in 2 cases and 1 case respectively.