Fundamental and clinical studies on aztreonam in the pediatric field

Fundamental and clinical studies on aztreonam (AZT), a new monobactam antibiotic, were performed in the pediatric field. The MICs of AZT were assessed against the clinically isolated strains in the pediatric infections. AZT showed an excellent antibacterial activity against Gram-negative bacteria, i.e., against E. coli (20 strains), K. pneumoniae (9), P. mirabilis (16), P. vulgaris (5), P. aeruginosa (10), S. typhimurium (4) and H. influenzae (11); the MICs of AZT against the above strains were less than 0.39 microgram/ml, 0.10 microgram/ml, 0.024 microgram/ml, 0.024 microgram/ml, 6.25 micrograms/ml, 0.10 microgram/ml and 0.10 microgram/ml, respectively. However, antibacterial activity of AZT against Gram-positive bacteria was inferior to that against Gram-negative bacteria, i.e., against the strains of S. aureus (16) and S. pyogenes (4), those MICs were more than 400 micrograms/ml and 3.13 micrograms/ml, respectively. Serum concentrations and urinary excretion of AZT were measured in 2 children aged 7 and 11 years after a single intravenous injection at the dose of 20 mg/kg. The mean serum concentration of AZT followed by the injection 62.5 micrograms/ml at 1/4 hour, 28.5 micrograms/ml at 1/2 hour, 16.5 micrograms/ml at 1 hour, 12.0 micrograms/ml at 2 hours, 3.6 micrograms/ml at 4 hours and 1.1 micrograms/ml at 6 hours, respectively. The mean half-life (beta-phase) was 1.24 hours. The mean urinary concentrations after the injection were 5,000 micrograms/ml in 0-2 hours, 1,650 micrograms/ml in 2-4 hours and 611 micrograms/ml in 4-6 hours and the mean urinary recovery rate up to 6 hours was 61.2%. These results in our studies were considered to be comparable with those reported in adults. In our clinical studies, AZT was administered to a total of 14 cases, i.e., acute pneumonia (4 cases), acute pyelonephritis (4), acute enteritis (5) and acute sppurative cholangitis (1). Clinical effect of AZT was excellent or good in 13 cases except fair in 1 case with acute enteritis and the efficacy rate (excellent and good) was 92.9%. With regard to bacteriological effect, all the strains of H. influenzae (3), E. coli (2), P. mirabilis (1) and P. vulgaris (1) were eradicated, but, S. typhimurium (4) was not eradicated. Neither side effect nor abnormal laboratory findings were observed during the study.     

Fundamental and clinical studies of aztreonam in pediatric infections

Fundamental and clinical studies were carried out with aztreonam (AZT), a new monocyclic beta-lactam antibiotic, in pediatric infections. Results were as follows. The mean half-lives in the vein blood were 1.09 hours, 1.18 hours, 1.22 hours after injection, when the doses were 10, 20 and 40 mg/kg, respectively. Dose response was observed. The average recovery rates in the urine between 0 and 6 hours were 40.2%, 42.3%, 50.8% when the doses were 10, 20 and 40 mg/kg, respectively. The antibacterial activity of AZT against 16 clinical isolates were determined in comparison with those of ABPC, CPZ, LMOX and CTX. Against 8 clinical isolates of E. coli and 3 of H. influenzae, the activity of AZT was equal or superior to that of CPZ, LMOX and CTX, and way by far superior to that of ABPC. Twenty-three pediatric patients received AZT in doses ranging from 48 to 79 mg/kg divided 3 times a day; 12 cases of urinary tract infection, 9 cases of respiratory tract infection and 2 cases of bacterial enterocolitis. The rate of clinical effectiveness was 100%. No side effect was observed. Slight elevation of GOT and GPT were observed in 2 cases, increase of platelet count in 2. All were considered to be transient and mild.     

Fundamental and clinical studies on aztreonam in the gynecological field

Aztreonam (AZT), a new monocyclic beta-lactam antibiotic was studied on clinical efficacy for infectious disease in gynecological field. At about 80 minutes following intravenous injection of 1 g dose of AZT, it penetrated well into internal genital organs at therapeutic levels. Moreover it transferred very fast and enough into intrapelvic dead space exudate, and its level was kept still as high at 12 hours after administration. AZT was given to 20 women affected with gynecological infectious disease. The outcome of AZT therapy was as follows: effective in 5 out of 6 patients (83.3%) administered intravenously and in all of 14 patients (100%) received intramuscularly. Notable adverse effects or abnormal laboratory findings were not observed except 1 case of diarrhea and 2 cases of transient and slight elevation of serum CPK and transaminases. Based on these results, we may conclude that AZT is a highly effective and a very safe antibiotic for the treatment of infectious disease in gynecological field.     

Laboratory and clinical studies of aztreonam in the pediatric field

The authors have carried out the laboratory and clinical studies of aztreonam (AZT) and obtained the following results. The antibacterial activities of AZT against the clinical isolates of E. coli, K. pneumoniae and P. aeruginosa were measured by the agar dilution method with inoculum size of 10(6) cells/ml. The susceptibility distribution of E. coli to AZT ranged from 0.025 or lower to 1.56 microgram/ml, and the peak of distribution was 0.05 microgram/ml. The peak of susceptibility distribution of K. pneumoniae was 0.025 microgram/ml or lower, and the distribution of P. aeruginosa ranged from 0.1 to 100 micrograms/ml higher and the peak of distribution was 3.13 micrograms/ml. After intravenous bolus injection of 20 mg of AZT in 4 children, the mean peak serum level was 117 +/- 35.1 micrograms/ml at 15 minutes after injection, and half-life time was 1.42 hours. The mean urinary excretion rates was 63.2 +/- 30.6% up to 6 hours after bolus injection of 20 mg/kg of AZT. AZT was given 11 cases with bacterial injection. Daily doses of AZT were from 41.7 to 94.9 mg/kg. Clinical results obtained were excellent and good responses in 8 of 11 cases (72.7%). No side effect was observed.     

Laboratory and clinical studies on aztreonam in the pediatric field

Laboratory and clinical studies were performed as follows on aztreonam (AZT), a new monobactam antibiotic. Pharmacokinetics Serum concentrations of AZT were measured in 1 patient given 20 mg/kg by intravenous bolus injection. The peak concentration was 100 micrograms/ml at 15 minutes, and T 1/2 was 1.85 hours. Clinical efficacy AZT was administrated intravenously to 10 patients in doses of 59.2-170.7 mg/kg (average 76.1 mg/kg) t.i.d. for 3-8 days (average 5.3 days); 5 with pneumonia, 1 with bronchitis, 1 with lymphadenitis, 1 with sepsis (suspected) and 2 with urinary tract infections. The overall efficacy rate was 80%, i.e., efficacy was excellent in 5, good in 3, fair in 1 and poor in 1. Bacteriological efficacy was excellent, i.e., 4 of 4 Gram-negative strains disappeared. Any clinical side effects and laboratory abnormalities were not observed. The above results suggest that AZT is a useful antibiotic for treating pediatric bacterial infections, especially due to Gram-negative bacteria.     

Fundamental and clinical studies of aztreonam in the field of obstetrics and gynecology

Aztreonam (AZT, E-0734), a new beta-lactam antibiotic, was fundamentally and clinically studied. The following results were obtained. The serum and internal genital tissue levels for AZT after 1 g intravenous injection had been kept at more than about 20 micrograms/ml and 3.0 micrograms/g, respectively, during 1 hour. AZT was administered at 1-2 g of daily dose by intravenous injection or intravenous drip infusion to 5 patients with obstetric and gynecological infections, comprising 1 of pyometra, parametritis, Bartholin's abscess, puerperal endometritis and diffuse peritonitis. Clinical efficacy was; excellent in 1 puerperal endometritis case, good in 2 cases and poor in 2 cases. Neither side effect nor abnormal laboratory finding was observed.     

Fundamental and clinical studies on aztreonam in the field of obstetrics and gynecology

Fundamental and clinical studies on aztreonam (AZT), a new synthetic monobactam antibiotic, were performed and following results were obtained. Concentration of AZT was examined in serum, internal genital tissues and retroperitoneal fluid after a single intravenous administration of 1 g dose. The venous serum level of AZT was 114.0 micrograms/ml at 10 minutes after the administration, then decreased to 7.0 micrograms/ml at 3 hours. Since concentration of AZT in examined tissues showed wide variation, it was irrelevant to calculate transfer ratio. Concentration in retroperitoneal fluid made the peak of 40.0 +/- 22.6 micrograms/ml at 1 hour after the administration, then slowly decreased to 13.4 +/- 3.2 micrograms/ml at 6 hours. Judging from above data, the transfer of AZT to retroperitoneal fluid was favorable. In clinical trial, AZT was given to 17 cases with obstetrical and gynecological infections such as endometritis, uterine adnexitis, pelvic peritonitis, parametritis and lymphocystitis. The efficacy was evaluated as excellent in 2 cases, good in 12 and poor in 3, and efficacy rate was 82.4%. No side effects were observed in any of the cases. In laboratory findings, transient elevation of liver function in 2 cases and eosinophilia in 1 case were noticed.     

Fundamental and clinical studies on aztreonam

Aztreonam (AZT), a new monocyclic beta-lactam antibiotic, was studied on the transfer into intrapelvic tissues and on the clinical efficacy in the treatment of 19 cases of obstetrical and gynecological infections. The AZT levels were examined in the pelvic dead space exudate in 6 patients who received radical hysterectomy due to uterocervical cancer. The simulation curves for AZT were well performed after the decision of the pharmacokinetic parameters using the two-compartment model. Following 1-hour intravenous drip infusion of 1 g of AZT, the peak concentration of AZT in cubital venous blood was estimated 73.3 micrograms/ml at the end of infusion. The peak concentration of AZT in the pelvic dead exudate was estimated 18.6 micrograms/ml at 2.31 hours after infusion. Following intravenous 1-hour drip infusion of 1 g, the transferred level of AZT into uterine tissues was maintained at the effective concentration which means the excess level of the MIC against clinical isolates often observed in the field of obstetrics and gynecology. AZT was administered 2-4 g/day in 2 times a day by intravenous drip infusion for 60-90 minutes. The subjects were 19 patients with the following infections; pyometra (1), puerperal intrauterine infection (4), postoperative parametritis (4), pelvioperitonitis (2), purulent lymphocyst (1), acute salpingoophoritis (1), vaginal stump abscess (1), Douglas abscess (2), pelvioperitonitis + pyosalpinx (2), vulval abscess (1). Clinical efficacy was; excellent in 2 cases, good in 11 cases and poor in 6 cases. No notable side effect or abnormal laboratory finding was noted.     

Fundamental and clinical studies of aspoxicillin in the pediatric field

Aspoxicillin (ASPC), a new semisynthesized penicillin, was administered to 20 children; by one shot intravenous injection in the doses of 10, 20 and 40 mg/kg to each of 3 children, and by intravenous drip infusion in the doses of 20 and 40 mg/kg over a period of 1 hour to 8 and 3 children, respectively, and the serum levels, urinary levels and recovery rates were determined. ASPC was administered to 1 patient with tuberculous pleurisy in the dose of 20 mg/kg by one shot intravenous injection, then the thoracic fluid level and serum level were determined. In addition, ASPC was administered to 3 children with tonsillitis, 3 with bronchitis, 40 with pneumonia, one each for pleuropneumonia, pleurisy, lung abscess, scarlet fever, staphylococcal scalded skin syndrome and purulent lymphadenitis and 2 with UTI (total 54 children), in the mean dose of 81.4 mg/kg/day t.i.d. (12 children) or q.i.d. (42 children) by one shot intravenous injection for 6 days on the average, and clinical effectiveness and bacteriological response were evaluated in these cases, and adverse reactions and abnormal laboratory findings were examined in the 60 cases which included 6 drop-out cases. After the administration of ASPC to 9 children; 10, 20 and 40 mg/kg to each of 3 children, by one shot intravenous injection, the mean serum levels reached to the peak of 58.4, 147.0 and 221.0 mcg/ml, respectively, in 5 minutes. The mean half-lives were 1.03, 1.01 and 1.23 hours, and the mean areas under the curve (AUCs) were 44.9, 94.1 and 192.9 mcg X hr/ml, respectively. A dose response was seen among the 3 dosage levels. After the administration of ASPC to 11 children; 20 and 40 mg/kg to 8 and 3 children, respectively, by intravenous drip infusion over a period of 1 hour, the mean serum levels reached to the peak of 58.2 and 114.0 mcg/ml, respectively, on completion of the administration. The mean half-lives were 1.22 and 1.09 hours, and the mean AUCs were 109.4 and 181.7 mcg X hr/ml, respectively. A dose response was observed between the 2 dosage levels. In the above mentioned each 3 cases receiving one shot intravenous injection in the dose of 10, 20 and 40 mg/kg, the mean urinary levels of ASPC reached to the peak of 1,000.0, 2,300.0 and 4,350.0 mcg/ml, respectively, at 0 approximately 2 hours after the administration, and the urinary recovery rates during the first 6 hours were 66.1, 66.5 and 56.9%, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)     

Fundamental and clinical studies of ceftazidime in the pediatric field

Ceftazidime ( CAZ ), a newly-developed parenteral cephem antibiotic, was administered to 8 children; by one shot intravenous (i.v.) injection in the doses of 20 and 40 mg/kg each to 2 children, and by 30 minutes' i.v. drip infusion in the doses of 10 and 20 mg/kg each to 2 children, and the serum levels, urinary levels and recovery rates were determined. CAZ was also administered to 2 patients with purulent meningitis, one complicated with subdural abscess and the other with bacteremia, in the doses of 19.2 and 50.7 mg/kg, respectively, by one shot i.v. injection, and the CSF level of CAZ was determined. In addition, CAZ was administered to 2 children with acute bronchitis, 1 with chronic bronchitis, 37 with pneumonia, 3 with pleuropneumonia, 1 each for purulent meningitis, purulent meningitis accompanied with subdural abscess and purulent meningitis with bacteremia, 5 with urinary tract infections and 3 with purulent lymphadenitis (total 54 children), in the mean dose of 85.8 mg/kg/day mostly in 4 divided doses by one shot i.v. injection for 9 days on the average, and clinical effectiveness and bacteriological response were evaluated in these cases, and adverse events and abnormal laboratory findings were examined in the 66 cases which included 12 drop-out cases. 1. After the administration of CAZ to 4 children; 20 and 40 mg/kg each to 2 children, by one shot i.v. injection, the mean serum levels got to the peak of 115.8 and 199.5 mcg/ml, respectively, at 5 minutes. The results were good, showing dose response. The mean half-lives were 1.48 and 1.37 hours, respectively. After the administration of 10 and 20 mg/kg of CAZ each to 2 children by 30 minutes' i.v. drip infusion, the mean serum levels got to the peak of 58.5 and 80.0 mcg/ml, respectively, on completion of the administration, showing dose response. The mean half-lives were 1.06 hours in the former 2 cases, and 1.38 and 3.26 hours, respectively, in the latter 2 cases. The reason for the prolongation observed in 1 case was not clear. 2. In the above mentioned each 2 cases receiving one i.v. injection, the mean urinary levels got to the peak of 4,240 and 4,445 mcg/ml, respectively, at 0-2 hours after the administration , and the urinary recovery rates during the first 6 hours were high, 95.7% and 99.5%, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)     

Fundamental and clinical studies of flomoxef in the pediatric field

Fundamental and clinical studies of flomoxef (FMOX, 6315-S) were conducted and the obtained results are summarized as follows. For the pharmacokinetic investigation, FMOX at 10 or 20 mg/kg was administered by intravenous drip infusion over 30 minutes. In the 10 mg/kg group, the maximum blood concentration was reached just after completion of the drip infusion with the mean concentration of 30.3 +/- 4.5 micrograms/ml, and the mean half-life was 0.734 +/- 0.196 hour. The 6-hour urinary excretion rate was 72.3%. In the 20 mg/kg group, which also showed the peak concentration immediately after completion of the drip infusion, the mean peak blood concentration was 54.3 +/- 9.7 micrograms/ml and the mean half-life was 0.628 +/- 0.185 hour. The 6-hour urinary excretion rate was 69.3%. The urinary recovery tended to be lower in children than in adults. Between 10 mg/kg and 20 mg/kg, a definite correlation was observed between dose levels and blood concentrations. In the clinical investigation conducted with a total of 30 patients (22 with respiratory tract infection, 3 with lymphadenitis, 2 each with urinary tract infection and cellulitis, and 1 with acute osteomyelitis), FMOX was found to be excellent in 14 cases, good in 9, fair in 1, poor in 1, and not evaluable in 5. The efficacy rate was, therefore, 92.0%. In the bacteriological evaluation, 8 out of 12 clinically isolated strains were eradicated, 2 unchanged and 2 unknown. The elimination rate was 80.0%. Regarding side effects, no abnormal clinical symptoms were observed. As abnormal laboratory values, eosinophilia, prolongation of APTT, increased platelet count, and a slight elevation of GOT were observed.     

Fundamental and clinical studies on aztreonam in pediatrics

Fundamental and clinical results of AZT in pediatrics were as follows. Pharmacokinetics of AZT was studied for 1 case with resulting high serum concentration and a half-life of approximate 1 hour. AZT was administered to 10 patients with bacterial infections with 100% clinical efficacy and 62.5% bacterial elimination. Side effect was 1 case of diarrhea. There were no abnormal laboratory or coagulation test findings nor vitamin K deficiency, platelet hypofunction or effects on intestinal bacterial flora. AZT was considered to be high in safety. The administration of 20 mg/kg AZT 3 times a day was considered to be an effective treatment for pediatric Gram-negative infections.     

Fundamental and clinical studies on cefuzoname in the pediatric field

Cefuzoname (CZON) one of the aminothiazolyloxyiminoacetamido cephalosporins, was studied for its antibacterial activity, absorption and excretion, concentration in the cerebrospinal fluid (CSF) and the penetration, and clinical efficacy. The following are a summary of the results: 1. Antibacterial activity; The antibacterial activity of CZON was studied on clinically isolated Staphylococcus aureus (cefazolin (CEZ)-susceptible and CEZ-tolerant strains), Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis. Compared with CZON were cefmenoxime (CMX), latamoxef (LMOX), cefoperazone, cefmetazol (CMZ), cefotiam and CEZ, but for S. aureus cefamandole (CMD) was replaced for CPZ. Activities of CZON against S. aureus, both CEZ-susceptible and CEZ-tolerant strains, were superior to those of 6 control drugs. The distribution of MICs for the CEZ-susceptible strains was 0.10-12.5 micrograms/ml, and for the CEZ-tolerant strains 0.20-greater than 100 micrograms/ml. MIC peaks were 0.39 micrograms/ml and 0.78-1.56 micrograms/ml for CEZ-susceptible and CEZ-tolerant strains, respectively. Against both susceptible and tolerant strains, CZON showed superiority to CMZ and CMD, which are used prevalently and used for Methicillin-resistant S. aureus also. Distributions of MICs of CZON (and the peak of MICs) on E. coli, K. pneumoniae, and P. mirabilis were less than or equal to 0.025-1.56 (less than or equal to 0.025), less than or equal to 0.025-25 (less than or equal to 0.025-0.05), less than or equal to 0.025-25 (less than or equal to 0.025) micrograms/ml, respectively, showing CZON's similar antibacterial activity to those of cephalosporins, CMX and LMOX, which are 5th group. 2. Absorption and excretion: Eight patients, aged 10 months to 15 years, were administered with CZON 20 mg/kg, one shot intravenously. Serum concentrations somewhat varied from patient to patient, but the mean value was 48.7 micrograms/ml after 30 minutes of administration which decreased rapidly to 13.3 micrograms/ml after 1 hour, to 3.4 micrograms/ml after 2 hours, to 1.14 micrograms/ml after 4 hours, and to 0.15 microgram/ml after 6 hours. Half-lives were 0.67-1.47 hours, with the mean of 0.87 hour. Urinary recovery rates were 24.7-55.9%, with the mean of 45.1%, in 6 hours after administration. 3. CSF concentration and penetration rate: To 4 pediatric patients with purulent meningitis, CZON 25 mg/kg or 50 mg/kg was administered and the concentration in CSF was measured.(ABSTRACT TRUNCATED AT 400 WORDS)     

Fundamental and clinical studies on cefixime in the pediatric field

Fundamental and clinical studies on cefixime (CFIX), a new oral cephem antibiotic, were carried out in the pediatric field. The results were as follows: Serum concentrations and urinary recovery rates were determined after oral administration of CFIX at doses of 3 mg/kg and 6 mg/kg in 2 cases each (4 cases in total). The mean serum concentrations of CFIX were 0.52 and 0.58 micrograms/ml at 2 hours, 0.80 and 1.42 micrograms/ml at 4 hours, 0.73 and 1.36 micrograms/ml at 6 hours, 0.54 and 1.12 micrograms/ml at 8 hours, respectively. The mean peak serum concentration of CFIX was obtained at 4 hours after administration, with serum half-lives (T1/2) of 3.77 and 5.30 hours, respectively. The mean cumulative urinary recovery rates within 12 hours after administration of CFIX at doses of 3 mg/kg and 6 mg/kg were 8.4% and 6.8%, respectively. Antibacterial activities of CFIX against clinically isolated strains of S. pyogenes, S. pneumoniae. E. faecalis, S. aureus, E. coli, H. influenzae, H. parainfluenzae were compared with those of amoxicillin (AMPC), cefaclor (CCL), and cephalexin (CEX). It was observed that CFIX was a little less active than AMPC against S. pyogenes and S. pneumoniae, but CFIX was more active than CCL and CEX. CFIX was the most active against E. coli, H. influenzae and H. parainfluenzae. Twenty-one pediatric patients with bacterial infections (10, tonsillitis; 4, pharyngitis; and 7, urinary tract infections) were treated with CFIX at doses of 1.5-6.0 mg/kg in 2 or 3 times daily for 4-10 days. The efficacy rate was 95.2% clinically and 91.3% bacteriologically. No adverse reactions were observed. An abnormal laboratory finding (slight elevation of S-GOT and S-GPT) was observed in 1 case.     

Fundamental and clinical studies on aspoxicillin in the pediatric field

Fundamental and clinical studies of aspoxicillin (ASPC, TA-058), a new penicillin antibiotic, were performed in pediatric field. Antimicrobial activity MIC of ASPC was compared with that of piperacillin (PIPC), ampicillin (ABPC) and carbenicillin (CBPC) for clinical isolates of S. aureus (24 strains), S. pyogenes (22 strains), H. influenzae (18 strains), E. coli (21 strains) and K. pneumoniae (23 strains). MIC of ASPC against S. pyogenes was distributed in less than 0.39 microgram/ml and this numerical value of MIC was very superior. MIC distributions of ASPC against S. aureus, H. influenzae and E. coli had 2 peaks respectively. It was presumed that the results are due to an existence of beta-lactamase producing strains. The sensitive strains in those were distributed in less than 1.56-12.5, less than or equal to 0.10 and 0.78-3.13 micrograms/ml, respectively, and those numerical value of MIC was superior. While against K. pneumoniae, all strains were distributed in more than 12.5 micrograms/ml and the antimicrobial activity of ASPC was very inferior. ASPC was as active as PIPC and ABPC against S. pyogenes, but more active then CBPC, ASPC was less active against S. aureus than PIPC and ABPC, but more active than CBPC. And ASPC was less active against H. influenzae and E. coli than PIPC, but more active than ABPC and CBPC. Against K. pneumoniae, strains that showed somewhat low numerical value of MIC at only PIPC were observed, but antimicrobial activities of ABPC and CBPC, as well as ASPC were very inferior. Absorption and excretion Serum level and urinary excretion of ASPC in 6 pediatric patients of 4 months to 12 years of age after one shot intravenous injection of 20 mg/kg were examined. The serum mean levels were 51.7 micrograms/ml at 1/4 hour, 38.2 micrograms/ml at 1/2 hour, 22.9 micrograms/ml at 1 hour, 3.0 micrograms/ml at 4 hours and 1.0 microgram/ml at 6 hours after injection, respectively. The mean half-life of serum level was 1.03 hours. The mean urinary levels were 4,646 micrograms/ml for 0-2 hours, 1,773 micrograms/ml for 2-4 hours and 299 micrograms/ml for 4-6 hours. The mean urinary recovery rate within 6 hours after injection was 64.7%. Clinical studies In order to evaluate clinical response, bacteriological response and side effects, ASPC was applied to 28 cases, i.e., 5 cases of acute purulent tonsillitis, 2 cases of acute purulent otitis media, 2 cases of acute bronchitis and 19 cases of acute pneumonia.(ABSTRACT TRUNCATED AT 400 WORDS)     

Fundamental and clinical studies on cefixime in pediatric field

Cefixime (CFIX) was evaluated for pharmacokinetics, therapeutic effectiveness on infection, safety, and bacteriological effectiveness in pediatrics. The following is a summary of the results. Pharmacokinetics in 4 children, 2 each receiving a single dose of 1.5 mg or 6.0 mg per kg body weight, were examined. Peak serum CFIX concentrations after the dose of 1.5 mg/kg were 1.12 and 1.34 micrograms/ml, and the serum half-lives were 1.83 and 3.53 hours. For the children administered with 6.0 mg/kg of CFIX, the respective figures were 2.50 and 7.46 micrograms/ml, and 6.77 and 6.64 hours. The 12-hour urinary recoveries were 4.9 and 34.1% and 9.4 and 25.4% for the small and the large doses, respectively. Therapeutic effectiveness in 19 children with infections was "excellent" in 14 and "good" in 5, with an effectiveness rate of 100%. Bacteriological effectiveness was evaluated in 10 children. Classified by causative organisms, 5 cases had H. influenzae, 2 each H. parainfluenzae and S. pyogenes, and 1 mixed infection by H. influenzae and S. pneumoniae. Only the H. influenzae in the child with mixed infection resisted the therapy, and all the other pathogens were successfully eradicated. No side effects were recorded. The only abnormal laboratory test finding attributed to CFIX was eosinophilia in 2 children.     

Fundamental and clinical studies of ceftizoxime suppositories in the pediatric field

The fundamental and clinical studies of ceftizoxime suppository (CZX-S) in the field of pediatrics were made, with the following results. The serum concentration of CZX in the CZX-S 250 mg-administered group peaked 6.00-22.5 micrograms/ml during the period of 15 minutes to 1-hour after dosing, and gradually declined thereafter. The half-life was 1.37-3.81 hours. In the CZX-S 125 mg-administered group, the serum concentration peaked 2.25-21.0 micrograms/ml at 15-30 minutes after dosing and decreased with time. The half-life was 0.95--1.84 hours. The 6-hour urinary recovery rate of CZX in the CZX-S 250 mg group was 22.0-47.5%. The 6-hour urinary recovery rate in the CZX-S 125 mg group was 17.2-25.3%. CZX-S was given 12-73 mg/kg/day (divided into 1-3 times) to 7 children with respiratory tract infection etc. who were considered to respond well to the drug. The clinical effectiveness rate was 100% inclusive of "excellent" and "good". The side effect of pain on insertion was encountered in 1 child.     

Fundamental and clinical studies on aztreonam in obstetrics and gynecology

Fundamental and clinical studies on gynecological use of aztreonam (AZT), a new monobactam, were performed with following results. Following the intravenous administration of 1 g dose of AZT, the transfer of AZT to pelvic dead space exudate was good, in which the concentration of that was 14.9 micrograms/ml (2 hours), 15.3 micrograms/ml (3 hours) after injection. The transfer of AZT to serum of umbilical cord and amniotic fluid was excellent. In a clinical trial, AZT was given to 5 patients with obstetric and gynecological infections. The clinical efficacy was evaluated as excellent in 1 case and good in the other 4 cases. No adverse effects were observed in any of the patients treated with AZT.     

Fundamental and clinical studies of sulbactam/cefoperazone in the pediatric field

To 6 cases of children in 2 groups of 3 each, newly developed sulbactam/cefoperazone (SBT/CPZ) was given at 20 and 40 mg/kg by intravenous bolus injection, respectively, and the serum and urinary concentrations and recoveries of SBT and CPZ were determined. To 1 case of purulent meningitis, this drug was given at 40 mg/kg by intravenous bolus injection, and the cerebrospinal fluid and serum concentrations of SBT and CPZ were determined. Susceptibility tests to SBT/CPZ and CPZ of total 289 strains were conducted; Gram-positive cocci tested consisted of 26 S. aureus strains, 20 S. pyogenes strains and 21 S. pneumoniae strains, and Gram-negative bacilli consisted of 24 H. influenzae strains, 22 E. coli strains, 26 K. pneumoniae strains, 24 E. cloacae strains, 21 E. aerogenes strains, 19 Citrobacter sp. strains, 20 S. marcescens strains, 23 P. mirabilis strains, 23 indole-positive Proteus sp. strains and 20 P. aeruginosa strains. SBT/CPZ was given to total 43 cases at a mean daily dosage of 80.4 mg/kg, in 3 or 4 divided doses (6 cases in 3 and 37 cases in 4), 1 case receiving the drug by drip infusion over 30 minutes (in 3 divided doses) and all the other 42 cases by intravenous bolus injection, for 7 days on an average. They consisted of 2 cases of tonsillitis, 1 case of otitis media, 1 case of otitis media associated with mastoiditis, 30 cases of pneumonia, 1 case of suspected septicemia, 1 case of purulent meningitis, 5 cases of urinary tract infection, 1 case of purulent lymphadenitis and 1 case of submaxillaritis. And the clinical and bacteriological effects were evaluated. Also, side reactions and laboratory examinations for abnormal values due to administration of this drug were made on 47 cases including 4 drop-outs. The following results were obtained: After administration of this drug to 2 groups of 3 children each at 20 and 40 mg/kg by intravenous bolus injection, mean serum concentrations of both SBT and CPZ reached the peaks in 5 minutes; SBT levels were 60.9 and 124.7 micrograms/ml for the 2 groups and CPZ levels were 105.0 and 214.1 micrograms/ml, respectively. In either group, CPZ levels were 1.7 times as high as SBT levels, and there was observed a dose-response in both. In the 20 mg/kg group, mean half-lives of SBT and CPZ were 0.96 and 1.24 hours, respectively, and in the 40 mg/kg group, they were 1.01 and 1.32 hours, CPZ values tending to be longer.(ABSTRACT TRUNCATED AT 400 WORDS)     

Preclinical and clinical studies on aztreonam in pediatric surgery

Aztreonam (AZT) was administered to immature infants, neonates and infants for preclinical and clinical studies. 1. Sufficient serum concentrations were obtained upon 1-hour intravenous drip infusion of AZT 40 mg/kg to infants with biliary atresia. The average T1/2 was about 1 hour and urinary recovery rates were in a range between 35.2 and 61.3%. Biliary recovery rates were 0.03-0.4%. 2. AZT was given to 5 cases for prophylaxis and the results showed its prophylactic effect in 3 cases. 3. AZT is effective against Gram-negative bacteria and its efficacies in the treatment of 4 infection-cases were "excellent" in 2 cases and "effective" and "somewhat effective" in 1 case each. 4. Neither side effects nor abnormal laboratory test values were observed in any of the 9 cases given AZT.