[Clinical studies on 9, 3"-diacetylmidecamycin in respiratory tract infections in the field of pediatrics (author's transl)].

UNLABELLED

Laboratory and clinical studies were performed on 9, 3"-diacetylmidecamycin (MOM), a new macrolide antibiotic in the field of pediatrics, and the results were as follows. Antibacterial activity: For 32 clinically isolated strains of Staphylococcus aureus, the MIC of MOM ranged from 0.78 to 1.56 micrograms/ml for 17 of the 32 strains, and exceeded 100 micrograms/ml for the 15 remaining strains with both inoculum sizes of 10(8) cells/ml and 10(6) cells/ml. For 27 strains of Streptococcus pyogenes, the MIC range was wide, varying from 0.10 to greater than or equal to 100 micrograms/ml and less than 1.56 micrograms/ml for about 2/3 of all the 27 strains. For 9 strains of Bordetella pertussis, the MIC ranged from 0.10 to 0.78 microgram/ml and 0.10 to 0.39 microgram/ml with the inoculum size of 10(8) cells/ml and 10(6) cells/ml, respectively. Comparing the antibacterial activity of MOM with that of midecamycin (MDM) and erythromycin (EM) against these 3 bacterial species, MOM was almost comparable to MDM, but about 2 or 3 tubes inferior to EM. Absorption and excretion: MOM was administered to 5 children (from 5 to 8 years old) at a dose of 10 mg/kg or 20 mg/kg at 30 minutes before breakfast. The peak of serum concentration was observed 30 minutes to 1 hour after administrations of both dosages: 0.52 to 1.71 micrograms/ml with 10 mg/kg and 0.88 to 1.77 micrograms/ml with 20 mg/kg. 0.09 to 1.10% and 0.94 to 1.19% of MOM were excreted in the urine within the first 6 hours, respectively.

CLINICAL RESULTS

MOM was administered to 28 pediatric patients with acute respiratory tract infections (acute pharyngitis; 2, acute purulent tonsillitis; 19, acute bronchitis; 4, acute pneumonia; 2 and whooping cough; 1). The overall clinical response was excellent in 10, good in 10, fair in 3 and poor in 5; the efficacy rate was 71.4%. Isolated S. pyogenes strains were eradicated in 6 out of 11 strains, reduced in 3 and unchanged in 2 strains. One strain of S. aureus was eradicated. One strain of non group A beta-Streptococcus was reduced. Haemophilus influenzae strains were reduced in 1 of the 4 strains and unchanged in 3 strains. The overall eradication rate was 41.2%. No side effects or abnormal laboratory findings were observed, but 1 case complained of a bitter taste.