[The studies on distributions of cefsulodin and cefotiam to human aqueous humor and cornea]

Distributions of cefsulodin (CFS) and cefotiam (CTM), new parenteral cephalosporins, to human aqueous humor and cornea were studied in comparison with those of sulbenicillin (SBPC) and cefazolin (CEZ), and pharmacokinetic analysis was made by theory of compartment model, to obtain the following results. 1. Maximum aqueous humor levels of CFS and CTM were noticed at 2.5 hours after the start of 1 g CFS or CTM administration by 30 minute intravenous drip infusion, with the levels of 3.6 micrograms/ml and 4.2 micrograms/ml respectively. On the other hand, in case of 5 g SBPC or 2 g CEZ administration maximum aqueous humor levels were 12.5 micrograms/ml and 5.2 micrograms/ml respectively. 2. The ratios of maximum aqueous humor level to plasma level of the same time in CFS, CTM, SBPC and CEZ were 15.0, 16.8, 6.4% and 5.5%. Distribution of CFS or CTM was 2 to 3 times better than that of SBPC or CEZ. 3. From the result of pharmacokinetic analysis, ratios of aqueous humor to plasma levels in area under curves (AUC) of CFS, CTM, SBPC and CEZ were 25.6, 29.9, 16.4% and 7.9% respectively. Maximum aqueous humor levels of CFS, CTM, SBPC and CEZ were 2.9, 3.6, 11.4 micrograms/ml and 4.3 micrograms/ml and biological half life of gamma-phase were 2.57, 2.31, 2.77 hours and 2.24 hours respectively. 4. Cornea levels of CFS or CTM at one hour after the start of 1 g CFS or CTM administration by 30 minutes intravenous drip infusion were 2.9 micrograms/g and 5.2 micrograms/g, and their ratios to plasma level were 7.5% or 14.3% respectively. In case of 5 g SBPC or 2 g CEZ administration, the cornea levels were 26.7 micrograms/g and 5.0 micrograms/g, and the ratios were 9.4% and 3.4% respectively. 5. From the above, the distribution of CFS or CTM to human aqueous humor and cornea is better than that of SBPC or CEZ, and it is considered that clinical usefulness of both CFS and CTM by parenteral administration is expected in intraocular infections.

[Clinical experience with cefsulodin in the field of otorhinolaryngology]

Clinical evaluation of cefsulodin (CFS) in treatment of infection in otorhinolaryngologic field was carried out and the following result was obtained. 1. Daily 1 to 5 gram of CFS was administered in divided dose to 9 cases of chronic purulent middle ear infection and postoperative wound infection. Clinical effectiveness was excellent, good and fair in 1, 2 and 5 cases, respectively. 2. No side effect as well as abnormal change of laboratory finding was observed. As for ototoxicity to be the most concerned matter of physicians, CFS seems to have no special problem. Thus, CFS is considered to be the useful drug for the treatment of chronic purulent middle ear infection and postoperative wound infection caused by P. aeruginosa in the field of otorhinolaryngology, and synergistic clinical effect will be expected by the combination therapy with other antibiotics or local administration of CFS.

[Clinical study of cefsulodin on Pseudomonas aeruginosa infections in otorhinolaryngology]

The clinical effect of cefsulodin (CFS) on Pseudomonas aeruginosa infections in otorhinolaryngology was studied in 10 patients. The overall clinical effectiveness was 80% (excellent 2, good 6, poor 2). Eradication rates of P. aeruginosa was 60%. No side effect and positive skin test were found in any cases. Examination of laboratory data before and after the administration revealed no abnormal findings in every cases.

[Clinical studies on cefsulodin in the field of pediatrics]

An anti-P. aeruginosa, cephalosporin, cefsulodin (CFS) was administered to 2 patients who were affected with inveterate urinary tract infection at ages of 1 year 8 months and 2 years, and another with pneumonia combined with lung fibrosis and bronchiectasia at 3 years. The clinical responses in 3 cases were "good" in 2 and "fair" in 1. The bacteriological responses to 3 strains of P. aeruginosa isolated in this clinical study were "eradicated" in 1, "decreased" in 1, and "unchanged" in 1. No side effects were observed.

[Experimental and clinical evaluation of cefsulodin in the pediatric field]

Antimicrobial, pharmacokinetic and clinical evaluation of cefsulodin (CFS) was made and the following results were obtained. 1. Antimicrobial activity of CFS against P. aeruginosa was similar to a little lower than that of GM. Antimicrobial activity of CFS against S. aureus was similar to that of SBPC and against E. coli CFS showed lower antimicrobial activity. 2. Twenty or 50 mg/kg CFS was administered by 1 hour intravenous drip infusion. Average serum levels at the completion of the infusion were 35.1 +/- 8.0, 114.5 +/- 36.1 micrograms/ml and 1.6 +/- 0.7, 4.5 +/- 3.2 micrograms/ml at 6 hours afterward with the half life times of 1.50, 1.29 hours respectively. In case of 12.1 mg/kg 1 hour intravenous drip infusion, peak serum level was 13.4 micrograms/ml at the completion of infusion, and the concentration in the sputum was 1.0 micrograms/ml at 5 hours after completion of infusion. Average serum levels of CFS by one shot infusion of 20 mg/kg were 58.4 +/- 6.8 micrograms/ml, 2.7 +/- 2.5 micrograms/ml at 15 minutes and 6 hours after injection respectively. Half-life time was 1.54 hours. Average urinary excretion rates of CFS were 64.4%, 64.2% and 48.9% up to 6 hours after 1 hour intravenous drip infusion of 20 mg/kg, 50 mg/kg CFS and one shot intravenous of 20 mg/kg CFS respectively. 3. CFS was administered to 2 pneumonia cases caused by P. aeruginosa, i.e. one was 15 years and 11 months old male accompanying bronchial asthma and the another 4 years old male with LENNOX syndrome. Neither bacteriological nor clinical efficacy was, however, observed. Side effect as well as bacterial superinfection were not observed.

[Subacute (5 weeks) subcutaneous toxicity study of cefsulodin using 3-week-old juvenile beagle dogs]

A subacute (5-week) subcutaneous toxicity study of cefsulodin (CFS) was carried out using 9 3-week old juvenile Beagle dogs. The dogs were distributed to 3 groups, each of which was constituted of 3 animals. Dogs in group I, II and III were given physiological saline (control), 300 mg/kg of cefazolin (CEZ, control drug) and 300 mg/kg of CFS, respectively. All animals used survived for 35 days of administration period. The changes, considered to be drug-related were histopathological changes at the sites of injection, which consisted inflammatory cellular infiltration and hyperplasia of fibroblast in subcutaneous tissue of skin. In terms of severity, CFS was less irritating than CEZ. CFS-related changes were not observed in other tests.

[Clinical evaluation of cefsulodin in Pseudomonas infections in children]

Cefsulodin (CFS) was evaluated for its safety and efficacy in 14 children with Pseudomonas aeruginosa infections. The diagnoses included pneumonia (4), sepsis (1), presumed sepsis (4), acute postoperative ascending cholangitis (1), acute postoperative peritonitis with wandering pneumonia (1), acute enterocolitis with acute UTI (1), recurrent UTI (1), and acute cystitis (1). CFS was administered intravenously with a daily dose of 93 to 299 mg/kg in the cases with normal renal functions. CFS was effective in all but one case both clinically and bacteriologically. A case of pneumonia whose isolate was resistant to CFS responded poorly. Mild transient eosinophilia was observed in 3 cases, but no severe adverse reactions were encountered. Peak MIC values of 18 clinical isolates of P. aeruginosa were 1.56 mcg/ml, 0.39 to 0.78 mcg/ml and 12.5 mcg/ml for CFS, gentamicin, and sulbenicillin, respectively. A half life of the serum CFS levels was 1.09 hours after intravenous bolus injection of 20 to 25 mg/kg of CFS (n = 2). A cerebrospinal-fluid level and biliary levels measured in cases with inflamed meninges or with cholangitis were well above the MIC value. From the present study, CFS appeared to be a safe and effective antibiotic when used in children with susceptible Pseudomonas infections. Combined use of another antibiotic should be considered in the case with polymicrobial infections because of the CFS's very narrow spectrum.

[Clinical studies of cefsulodin in the pediatric field]

Pharmacokinetic and clinical evaluations of cefsulodin (CFS) were made and the following results were obtained. 1. Pharmacokinetic study Three hundred fifty grams of CFS (20 mg/kg) was administered by 30 minutes intravenous drip infusion to 7 years old child (17.5 kg in weight). Serum concentrations of CFS at the end of the infusion and 1,1.5,2.5,6.5 hours thereafter were 46.0,44.9,23.0,11.9 mcg/ml and 0.6 mcg/ml respectively. Urinary recovery rate until 6 hours from the start of infusion was 66.2%. 2. Clinical study CFS was administered to the case of bronchitis with cystic fibrosis of the pancreas and bronchiectasia (treatment was made 2 times), and each 1 case of pyelonephritis with renal calculus and measles pneumonia with infantile spasm. All infections were caused by P. aeruginosa and administration and dosage of CFS was 47 to 86 mg/kg/day, 2 to 4 times daily by intravenous injection or intravenous drip infusion for 5 to 11 days. Result was good in 3 infections (2 cases) and fair in 1 case, i.e. measles pneumonia. Effectiveness rate was 75.0%. Side effect as well as abnormal change of laboratory findings were not observed. Thus, CFS is considered to be the useful drug for the treatment of pediatric infection caused by P. aeruginosa.

[Clinical studies on cefsulodin in the pediatric field]

Clinical studies on cefsulodin (CFS) in 6 patients with Pseudomonas aeruginosa infection were carried out and the results as follows. 1. Among 4 patients administered CFS intravenously, 3 patients (urinary tract infection 1, acute purulent otitis media 1, aspiration pneumonia 1) responded well. 2. Two patients with respiratory infection were treated CFS by nebulization. One responded well and another fair. 3. No side effects were observed.

[Clinical application of cefsulodin in gravely ill children with Pseudomonas infection]

Our investigation of cefsulodin in pediatric Pseudomonas infect ion produced the following results. 1. Cefsulodin (CFS) was administered intravenously by one shot or drip infusion in 3 patients with Pseudomonas infections. These diseases consisted of pneumonia with IgA deficiency, ALL with opportunistic infection, UTI with paraplegia due to spina bifida. CFS was effective in all cases. 2. Transient eosinophilia was observed in 1 case. But other side effect was not noted in any cases.

[The experimental and clinical studies on cefsulodin in the pediatric field]

A new cephalosporin cefsulodin (CFS) was studied basically and clinically and the following results were obtained. 1. The serum levels of 25 mg/kg of CFS administered intravenously were 39.5 mcg/ml after 30 minutes, 22.6 mcg/ml after 1 hour, 11.6 mcg/ml after 2 hours, 6.0 mcg/ml after 4 hours and 2.1 mcg/ml after 6 hours. The half life from serum was 84 minutes. 2. Clinical response on 4 cases of Pseudomonas aeruginosa infections were all good. 3. The slight elevations of GOT, GPT were observed by the drug administrations in 1 case. From the above results, CFS was effective drug to P. aeruginosa infections by intravenous administration of 25 mg/kg of CFS.

[Evaluation of cefsulodin in the field of pediatrics]

A few studies on cefsulodin (CFS) were performed and the following results were obtained. 1. High blood concentration was obtained with intravenous drip infusion of this drug, but it did not last long. 2. In 6 to 12 hours after the conclusion of the infusion, 52-81% of the dose was excreted in active condition. 3. Pseudomonas aeruginosal abscess was completely cured by intravenous drip infusion of this drug. A decrease in Pseudomonas aeruginosa was noted in urine in the case of acute pyelonephritis and in sputum in the case of pneumonia. The minimum inhibitory concentrations of this drug against P. aeruginosa isolated from various materials were below 12.5 micrograms/ml for all strains. 4. In all the patients including 3-month-old infants to whom 55-200 mg/kg of this drug was intravenously drip infused for 5 days, systemic or topical adverse reactions were not recognized. Nor did this drug give any effect on general blood condition, and liver and kidney functions. We plan to further study the clinical efficacy of this drug by adding more cases affected with P. aeruginosa in children.

Cefsulodin pharmacokinetics and otitis media

The pharmacokinetics of cefsulodin in the fluids of the ear and eye as well as in serum were studied after intramuscular administration of 200 and 400 mg/kg to eight groups of six guinea pigs. A retention of cefsulodin in the inner ear-similar to that of the aminoglycoside antibiotics - was observed. As the measured perilymph concentrations of cefsulodin and gentamicin are comparable on a weight for weight basis and as the clinical dosage of cefsulodin is much higher than that of gentamicin, the perilymph concentrations of cefsulodin reached in man are probably much higher than those of gentamicin. The results obtained are compared to those of mezlocillin, azlocillin and fosfomycin, Finally, the importance of the cefsulodin perilymph concentrations in the treatment and prophylaxis of infectious inner ear complications due to the most common pathogens of chronic otitis media as well as in the treatment of certain eye infections is discussed.

Precise high-performance liquid chromatographic procedure for the determination of cefsulodin, a new antipseudomonal cephalosporin antibiotic, in plasma

A simple and precise high-performance liquid chromatographic (HPLC) procedure was developed for the determination of cefsulodin, a new antipseudomonal cephalosporin antibiotic, in plasma. The analytical procedure involved ultrafiltration of samples that were buffered to prevent cefsulodin degradation, followed by injection into an HPLC system, utilizing a C18 reversed-phase analytical column, a mobile phase of acetonitrile-modified aqueous acetate buffer, and a UV spectrophotometric detector. Because of the simplicity of the procedure, the intraassay (or approximately 2%) and interassay (or approximately 3-4%) coefficients of variation were extremely low. Recoveries of drug were essentially quantitative in freshly buffered specimens and in those stored buffered and frozen for nearly 3 months. Calibration curves were rectilinear from the limit of quantification (or approximately 0.2 microgram/ml) to 200 micrograms/ml, as demonstrated by regression correlation coefficients averaging greater than 0.999 during routine analyses.

Comparison of the in vitro activity of new beta-lactams and aminoglycosides against clinical isolates of Pseudomonas aeruginosa

In vitro susceptibility of 338 clinical isolates of Pseudomonas aeruginosa to twelve antipseudomonal antibiotics were determined. Correlation between antibiotic resistance and serotypes was also performed. It was shown that the newer beta-lactams cefsulodin, piperacillin, azlocillin and mezlocillin had high biological activity against carbenicillin-resistant strains of P. aeruginosa. The most active aminoglycosides against gentamicin-resistant strains of P. aeruginosa were amikacin and netilmicin. Carbenicillin-resistant strains were most frequently observed among serotypes 4, 11 and NT group, and gentamicin-resistant strains among serotypes 3, 11 and NT group.

Gentamicin and cefsulodin efficacy in a rat abscess model

The pharmacokinetics and therapeutic efficacy of gentamicin and cefsulodin were studied in an abscess model in the rat induced by Pseudomonas aeruginosa and a foreign body. Both agents reached therapeutic concentrations in the abscess fluid and its ultrafiltrate and persisted longer in the abscess fluid than in blood. Gentamicin did not prevent the development of abscesses or reduce the bacterial inoculum when administered immediately following the induction of the abscesses. Cefsulodin sterilized 82.7 per cent of abscesses in 61.5 per cent of injected rats. Low oxygen tension present in the abscess was probably responsible for the inefficacy of gentamicin in this model, while not significantly diminishing the antibacterial activity of cefsulodin.

Treatment of pulmonary Pseudomonas aeruginosa infection in cystic fibrosis with cefsulodin

20 patients with cystic fibrosis and chronic pulmonary Pseudomonas aeruginosa infection underwent a total of 23 courses of treatment with a new cephalosporin, cefsulodin. The patients were given 100-150 mg/kg/day in 3 divided doses for 14 days, alone or in combination with tobramycin. Maximum serum levels were around 150 microgram/ml and 6-h levels above 5 micrograms/ml. 90% of the infecting strains were sensitive to 5 micrograms/ml in vitro. Apart from discomfort in direct relation to intravenous bolus injection the drug was well tolerated. Clinical improvement was pronounced, and in 5 cases. P. aeruginosa disappeared from bronchial secretions. Patients allergic to carbenicillin tolerated cefsulodin without signs of allergy. Cefsulodin thus appears to be an effective alternative to carbenicillin in the treatment of severe P. aeruginosa infections.

[Comparison of in vitro bacteriostatic effect of five betalactamins against Pseudomonas aeruginosa (author's transl)]

In vitro activity of two penicillins (ticarcillin and azlocillin) and three cephalosporins (cefoperazone, cefsulodin and ceftazidime) was compared against one hundred clinical isolates of Pseudomonas aeruginosa originated in two different Paris hospitals. Twenty strains were resistant to carbenicillin at a concentration of 128 mg/l. Minimal inhibitory concentrations (MICs) were determined by a twofold agar dilution method. The required ceftazidime concentration to inhibit 90 p. cent of the carbenicillin-susceptible isolates was 1,9 mg/l. To achieve the same inhibition, 3,9 mg of cefsulodin, 12 mg of cefoperazone, 14 mg of azlocillin or 38 mg of ticarcillin per liter were needed. Against the 209 carbenicillin-resistant isolates, ceftazidime remained active at concentrations lower than 2 mg/l in 90 p. cent of the cases. To obtain such an inhibition with the other antibiotics higher concentrations were needed.

[Synergistic activity between ticarcillin, azlocillin, cefsulodin, ceftazidime and tobramycin or amikacin against Pseudomonas aeruginosa (author's transl)]

Activity of azlocillin, cefsulodin, ceftazidime, ticarcillin in combination with amikacin or tobramycin was investigated against 17 Pseudomonas aeruginosa isolates. Synergistic activity was evaluated by the microtiter checkerboard technique. The bactericidal effect of the antibiotic combination was determined by subculturing onto agar and into broth. Synergistic activities of cefsulodin and ticarcillin combined with amikacin or tobramycin were similar in the inhibitory as well as in the bactericidal tests. Synergistic effects of the combination of ceftazidime and amikacin or tobramycin were moderate or indifferent in the inhibitory and bactericidal tests. The combination of azlocillin and amikacin or tobramycin produced synergistic effects greater in bactericidal tests than in inhibitory tests. The bactericidal synergistic activities of the combinations of azlocillin, cefsulodin, ticarcillin were similar. There was no difference between amikacin and tobramycin combined with a beta-lactamine. Antagonism was not observed. A synergistic effect of the combinations was observed against 4 isolates resistant to tobramycin and/or ticarcillin. However the result of the interaction seemed to depend upon the level of resistance to the antibiotic : if the MIC or the MBC of either antibiotic in the test combination was very high, synergy could not be achieved.

[Comparative activity of cefsulodin on Pseudomonas aeruginosa, Acinetobacter and Enterobacteriaceae (author's transl)]

Cefsulodin, a new semi-synthetic cephalosporin, is characterized by its activity against P. aeruginosa. In this study the authors compared this new molecule with other four betalactamines, carbenicillin, ticarcillin, azlocillin and mezlocillin, and two aminoglycosides, amikacin and netilmicin. Two hundred and forty five strains studied were 100 Pseudomonas aeruginosa, 20 Acinetobacter, 42 Proteus, 21 Serratia, 22 Enterobacter, 20 Klebsiella and 20 E. coli. One hundred twenty strains of these showed carbenicillin resistant phenotype. MIC were determined by the agar dilution method. Cefsulodin was only active on Pseudomonas aeruginosa. MICs were at least 16 mg/l in the other species. On carbenicillin susceptible P. aeruginosa strains, the average MIC of cefsulodin, amikacin and netilmicin was 1 mg/l, and MICs of azlocillin, mezlocillin, ticarcillin and carbenicillin were 4-8 mg/l, 8 mg/l, 16 mg/l and 32 mg/l, respectively. On carbenicillin resistant P. aeruginosa, ticarcillin and mezlocillin were not effective and MICs of azlocillin and cefsulodin were 16 mg/l and 4-8 mg/l, respectively. However, MICs were between 64 and 128 mg/l in 20 p. cent of carbenicillin resistant strains.

[Cephem antibiotics and alcohol metabolism: (1) Disulfiram-like reaction resulting from intravenous administration of cephem antibiotics]

Fifty to 500 mg/kg doses of the cephem antibiotics were intravenously injected to male rats twice a day for 3 days. After the last injection, the rats were fasted for 17 hours and then orally administered 2 g/kg or 20% ethanol. The blood levels of ethanol and acetaldehyde (AcH) were determined by gas chromatography. Cefotiam, cefsulodin, and cefazolin did not affect the blood levels of ethanol and AcH as compared with those of the control. Cefmetazole, cefamandole, and cefoperazone did not change the blood ethanol level, but these antibiotics increased the blood AcH level dose-dependently. Cefamandole was especially able to sustain a high blood AcH level for over 8 hours. All of the antibodies which increased blood AcH levels contain the 1-methyl-1H tetrazole-5-thiol (TZ) group in their chemical structure. Intravenous injection of TZ caused a significant increase of the blood AcH level without influence on the blood ethanol level. 1-(2-Dimethyl-aminoethyl 1H-tetrazole-5-thiol (MTZ), the functional group which is contained in cefotiam, did not affect the blood levels of ethanol and AcH. These results suggested that the disulfiram-like reaction of cefmetazole, cefamandole, and cefoperazone results from an increase of the blood AcH level, and the 3-substituent group in in aminocephalosporanic acid, i.e., TZ, is an important factor for the reaction.

[Clinical bacteriological studies on cefotiam and cefsulodin in the field of otorhinolaryngology]

Clinical bacteriological studies on cefotiam and cefsulodin in the field of otorhinolaryngology were carried out and the following results were obtained. 1) Aerobic and anaerobic Gram-positive bacteria were dominantly isolated from the clinical materials sent to the center from the clinical institutes. 2) It was considered that Streptococcus pneumoniae, Haemophilus influenzae and beta-Streptococcus played an important role in the primary infections in the field of otorhinolaryngology. Staphylococcus aureus was also frequently isolated from the primary infections. Peptostreptococcus spp. was dominantly isolated from peritonsillar abscess. Gram-negative bacilli (GNB) were mainly isolated from the chronic secondary infections. Among GNB, Pseudomonas aeruginosa and Proteus spp. were more frequently isolated. Staphylococcus aureus was also constantly detected in the secondary infections together with GNB. Anaerobic bacteria were isolated from 20.1% of the patients with chronic otitis media and 27.1% of sinusitis. 3) Cefotiam showed potent antibacterial activities against most isolates of Gram-positive and Gram-negative bacteria. 4) Cefsulodin showed potent antibacterial activities against clinically isolated Pseudomonas aeruginosa. Staphylococcus aureus and beta-Streptococcus were also susceptible to cefsulodin.

Cefsulodin kinetics in renal impairment

Cefsulodin kinetics were determined after a 500-mg dose to normal subjects and patients with varying degrees of renal insufficiency, including those requiring hemodialysis. Elimination kinetics were described by a two-compartment model. Steady-state volume of distribution was 0.26 l/kg regardless of renal function. When glomerular filtration rate (GFR) was more than 80 ml/min, elimination half-life (t1/2) was 1.9 hr, total body clearance (ClT) was 2.01 ml/kg/min, and renal clearance (ClR) was 1.09 ml/kg/ in. When GFR ranged from 79 to 53 ml/min, t1/2 was 2.9 hr, ClT was 1.17 ml/kg/min, and ClR was 0.65 ml/kg/min. In subjects with moderate renal failure in whom GFR was 32 to 22 ml/min, t1/2 was 5.7 hr, Clt was 0.66 ml/kg/min, and ClR was 0.26 ml/kg/min. In anuric patients t1/2 was 13.0 hr. and ClT was 0.19 ml/kg/min or 9.5% of ClT in normal subjects. There was a linear relationship between ClT and GFR such that ClT = 0.19 + 0.017 GFR (r = 0.95). During hemodialysis the average plasma flow was 122 ml/min, dialyzer plasma clearance was 50.9 ml/min, plasma drug concentration was reduced by 60%, and t1/2 fell to 2.1 hr. After dialysis the elimination rate appeared to return to that in nondialysis studies. Therefore, renal failure reduces the ClT of cefsulodin. In hemodialysis patients the maintenance dose of cefsulodin should be reduced to 10% of normal and 60% of the dose should be given after hemodialysis.

[Antibacterial activities of new cephems against clinically isolated organisms (author's transl)]

The antibacterial activities of cefotaxime (CTX), cefoperazone (CPZ), ceftizoxime (CZX), cefmenoxime (CMX), latamoxef (LMOX), cefotiam (CTM), cefazolin (CEZ), gentamicin (GM) and cefsulodin (CFS) were investigated. All causative organisms were isolated from patients with urinary tract infections treated in Tokai University Hospital. The results were as follows. 1) The MICs of CMX, CTX, and CZX against most of clinically isolated strains of E. coli, K. pneumoniae, Indole (-) Proteus sp. were 0.1 microgram/ml and lower. And then CTM, LMOX and CPZ showed similar antibacterial activities. 2) LMOX and GM showed potent antibacterial activities against C. freundii which was considered to be causative organisms of infections in rare cases. 3) Against S. marcescens, CMX, CTX, CZX, and LMOX showed very potent antibacterial activities. 4) Against P. aeruginosa, CFS, GM and CPZ showed moderate antibacterial activities. 5) Against Enterobacter sp., GM and CMX showed potent antibacterial activities.

Determination of cefsulodin, cefotiam, cephalexin, cefotaxime, desacetyl-cefotaxime, cefuroxime and cefroxadin in plasma and urine by high-performance liquid chromatography

Closely related methods for the determination of several cephalosporins in plasma and urine are described. Deproteinized plasma or diluted urine is directly injected on a RP-8 or RP-18 bonded-material column. Chromatography is performed either in the reversed-phase or the ion-pair mode. The limits of sensitivity range from 0.4 to 2 mumol of cephalosporins per liter of plasma, and from 20 to 100 mumol per liter of urine. The sensitivity may be improved two to five times by using precolumn loading, direct sample clean-up and automatic injection. The stability of the cephalosporins in plasma, urine and water and the reproducibility and accuracy of the methods are reported.

Agar (disk) diffusion test susceptibility of clinical isolates of Pseudomonas aeruginosa to azlocillin, cefotaxime, cefsulodin, lamoxactam, mezlocillin, and piperacillin

The standardized Bauer-Kirby agar diffusion test served to examine 100 clinical isolates of Pseudomonas aeruginosa against various recently introduced broad-spectrum penicillins and cephalosporins. Neither cefotaxime nor lamoxactam displayed significant activity against this microorganism. Azlocillin, cefsulodin, and piperacillin were significantly more effective (p less than 0.0001) than mezlocillin against the majority of isolates. When compared individually, azlocillin and piperacillin displayed comparable in vitro activity; the same was true for cefsulodin compared with piperacillin. On the other hand, cefsulodin was somewhat more active than azlocillin (p less than 0.05, greater than 0.01) against P. aeruginosa. These data should enable diagnostic laboratories to curtail the number of antimicrobial drugs routinely utilized to examine clinical isolates of P. aeruginosa for antibiotic susceptibility, i.e., piperacillin exclusively.

A turbidimetric study of the responses of selected strains of Pseudomonas aeruginosa to eight antipseudomonal beta-lactam antibiotics

Turbidimetric and morphologic responses to eight antipseudomonal beta-lactam antibiotics were compared for selected strains of Pseudomonas aeruginosa with different susceptibilities to carbenicillin. In conventional minimal inhibitory concentration tests, all of the newer antibiotics appeared more active than carbenicillin, and apalcillin and cefsulodin had the greatest overall activity. However, in turbidimetric tests the activity of apalcillin and three other N-acyl penicillins (azlocillin, mezlocillin, and piperacillin) was inferior to that of carbenicillin and the other agents. The N-acyl penicillins were also all susceptible to intrinsic pseudomonal beta-lactamase, so that dense bacterial populations inactivated these antibiotics in concentrations of greater 128 micrograms/ml during overnight incubation. Against carbenicillin-resistant strains, carbenicillin, ticarcillin, and sulbenicillin were the least active antibiotics, and cefsulodin had the best overall activity. Turbidimetric monitoring highlights the problems of interpreting the results of conventional minimal inhibitory concentration tests, particularly when large inocula are involved.

Cefsulodin concentrations in rabbit eyes after intravenous and subconjunctival administration

Experimental studies on rabbit eyes were performed to examine the penetration capacity of cefsulodin into the anterior chamber and the vitreous body. One group of animals was injected with 50 mg/kg body weight intravenously, the other group received 20 mg subconjunctivally. Samples of the anterior chamber and the vitreous body were taken from the anaesthetized animals after 15, 30, 60 and 120 min (6 eyes at each time). The corresponding serum concentrations were determined as well. Cefsulodin concentrations were measured microbiologically with agar diffusion tests. At each time studied, the antibiotic could be detected in the anterior chamber after intravenous injection. Concentrations ranged from 2 to 5.2 mg/l. Similar results were found after subconjunctival application. In no case the antibiotic was detectable in the vitreous body. The pharmacokinetics of cefsulodin in the rabbit eye seem to be comparable to the behaviour of other beta-lactam antibiotics and aminoglycosides. As cefsulodin is able to penetrate into the anterior chamber, it might be a useful antibiotic for therapy of eye infections caused by Pseudomonas aeruginosa.

Cefsulodin kinetics in healthy subjects after intramuscular and intravenous injection

We evaluated cefsulodin kinetics in normal subjects after 250-, 500-, and 1,000-mg, intramuscular injections and 500-, 1,000-, and 2,000-mg 30-min intravenous infusions. Twelve plasma and four urine samples were collected in the first 12 and 24 hr. Plasma samples were analyzed by a new, highly precise high-performance liquid chromatographic procedure developed in our laboratory and urine samples were analyzed microbiologically, using Pseudomonas aeruginosa as the test organism. Mean calculated peak plasma levels from the 250-, 500-, and 1,000-mg intramuscular doses were 5.46, 11.81, and 19.40 microgram/ml. After 500-, 1,000-, and 2,000-mg intravenous infusions peak levels were 32.7, 65.7, and 190.1 microgram/ml. Data from the intramuscular doses were fitted to a one-compartment open kinetic model, yielding a mean elimination half-life (t1/2) of 1.9 hr. Data from the intravenous infusions were fitted to a two-compartment open model, with a mean beta-phase t1/2 of 1.6 hr. Mean 0- to 24-hr urinary recoveries after the three intramuscular doses were 50.0%, 54.5%, and 51.2% of total dose; after the three intravenous doses they were 60.4%, 52.4%, and 54.0%. Cefsulodin kinetics were shown to be consistent and orderly.

Comparison of the renal excretory mechanisms of cefmenoxime and other cephalosporins: effect of para-aminohippurate on renal clearance and intrarenal distribution of cephalosporins in rabbits

The renal excretory mechanism of cefmenoxime in rabbits was compared with that of 6 other cephalosporins (cefotaxime, deacetylcefotaxime, cefotiam, cefazolin, cephaloridine, and cefsulodin). The clearance ratios (Cf-Drug/CInulin=CRf) of cefmenoxime (337) and cefazolin (73) were considerably higher than those of the 5 other cephalosporins (0.9-20). When p-amino-hippurate (PAH) was administered concurrently with each of the cephalosporins, the CRf values of the cephalosporins except for cefsulodin were significantly decreased. These findings indicate that cefmenoxime and the 5 other cephalosporins except cefsulodin are actively incorporated in the proximal tubular cells and secreted into the tubular lumen. In the case of cefotiam and cefsulodin, glomerular filtration tended to exceed urinary excretion with highest dose of PAH (40 mg/kg/minute), suggesting the possibility of tubular reabsorption of these drugs. On the other hand, glomerular filtration of cefmenoxime and the 4 other cephalosporins did not exceed urinary excretion. The drug concentration ratio of the cortex to medulla indicated that the tubular cell level of cefmenoxime was lower than, higher than, and similar to those of cephaloridine, cefotaxime, and the remaining cephalosporins, respectively. These results demonstrate that the renal excretory mechanisms of cefmenoxime is similar to that of cefazolin but not to that of the remaining cephalosporins.

[Treatment of Pseudomonas infections in children with cefsulodin (author's transl)]

Pseudomonas aeruginosa infections of twenty children in various age-groups were treated with Cefsulodin. Fifty percent of these cases received additional other antibiotics due to vital indication. In different underlying diseases such as IRDs, enteritis, omphalitis, necrotizing enterocolitis and urinary tract infection, this treatment achieved in eleven cases a lasting and in seven cases a temporary elimination of pseudomonas aeruginosa. No side effects were seen.

[Cefsulodine concentrations in cerebral ventricles during parenteral treatment of ventriculitis due to Pseudomonas aeruginosa (author's transl)]

Cefsulodine, a new B-lactamase-resistant cephalosporin, was used parenterally in combination with systemic and topical tobramycin to treat a patient with meningitis and ventriculitis due to Os, aeruginosa. Cefsulodine concentrations were measured simultaneously in serum and in cerebral ventricles. With doses of 500 mg four times a day, diffusion of the drug into meningeal spaces was rather poor, but with doses of 2 grams 8-hourly (100 mg/Kg/day cefsulodine concentrations in the ventricles were equal or superior to the average MICs against most Pseudomonas species. However, concurrent systemic and local administration of an aminoglycoside is required to ensure full bactericidal effect.

[Laboratory and clinical studies on cefsulodin (author's transl)]

Laboratory and clinical studies on cefsulodin (CFS), a new antipseudomonal cephalosporin antibiotic, were carried out and the following results were obtained. 1. The MIC of CFS against P. aeruginosa showed the peak of susceptibility at 3.13 mcg/ml in the inoculum size of 10(8) cells/ml and at 1.56 mcg/ml in the inoculum size of 10(8) cells/ml. It has a higher superiority as compared with gentamicin or piperacillin and gentamicin-resistant strains of P. aeruginosa were sensitive to CFS. 2. CFS was given to 3 patients with acute pneumonia and 5 patients with chronic cystitis which were all due to P. aeruginosa. Clinical effects were good in 2 patients and poor in a patient with acute pneumonia, and those were good in 3 patients and poor in 2 patients with chronic cystitis. Side effects were not recognized at all.

Effect of combination of cefsulodin and beta-lactam antibiotics against Serratia marcescens

The effect of cefsulodin in combination with various beta-lactam antibiotics was examined against Serratia marcescens. In vitro, the optimum ratio for all combinations tested was almost the same (cefsulodin - other antibiotic = 1:1 approximately 1:4). The combinations of cefsulodin-cefazolin and cefsulodin-cefotiam were found to have a synergistic effect and other combinations, such as cefsulodin-cefmenoxime, -ampicillin and -sulbenicillin, an additive effect with the checkerboard dilution and the fixed combination methods. The synergistic effect of cefsulodin-cefotiam was more potent than that of cefsulodin-cefazolin and the effect of both combinations was clearer with heavy than with light inoculum size. With the killing kinetic method, all combinations tested showed a synergistic effect. In vivo, the optimum combination ratios of cefsulodin-cefazolin and cefsulodin-cefotiam were 1:2 and 1:1, respectively, the protective effect of the latter combination being much stronger than that of the former. With the fixed combination method (cefsulodin - other antibiotic = 1:1 approximately 1:4), the effect of the combination of cefsulodin with all antibiotics except cefazolin and cefotiam was additive.

In vitro activity of MK0787 (N-formimidoyl thienamycin) and other beta-lactam compounds against Bacteroides spp

The susceptibilities of 82 strains of the Bacteroides fragilis group to eight beta-lactam compounds, lincomycin, and metronidazole were determined by using an agar dilution technique. MK0787 (N-formimidoyl thienamycin) was the most active compound, inhibiting all strains at a concentration of 1 microgram/ml. Metronidazole was the only other drug of similar activity. Of the beta-lactam compounds, cefoxitin and MK0787 showed uniform activity against all species, whereas most other compounds were relatively less active against Bacteroides distasonis and Bacteroides thetaiotaomicron than against B. fragilis and Bacteroides vulgatus. Using a well diffusion technique, we determined the relative stability of each beta-lactam compound to sonicated cultures of selected resistant strains. Whereas MK0787 was completely stable to inactivation--and with one exception, cefoxitin was also--ceftriaxone, cefotaxime, cephaloridine, and cefoperazone always showed some inactivation, often quite substantial. Moxalactam and ceftazidime were completely stable to some of the enzyme preparations.

Cefsulodin: antibacterial activity and tentative interpretive zone standards for the disk susceptibility test

Cefsulodin (SCE-129) is a cephalosporin with a spectrum of antibacterial activity largely limited to Pseudomonas aeruginosa and Staphylococcus aureus. Cefsulodin was compared with carbenicillin, ticarcillin, mezlocillin, and piperacillin against 779 nonenteric gram-negative bacilli and staphylococci collected from five geographically separate institutions. Against P. aeruginosa, cefsulodin was somewhat more active than piperacillin and much more active than other penicillins. In addition, cefsulodin was active against penicillinase-producing strains of S. aureus. Collaborative efforts in three laboratories led to the following tentative zone size breakpoints for 30-micrograms cefsulodin disks: susceptible greater than or equal to 18 mm (minimal inhibitory concentration) [MIC] less than or equal to 16 micrograms/ml) and resistant less than or equal to 14 mm (MIC greater than or equal to 64 micrograms/ml). These zone standards are still tentative since the dosage schedule has not yet been defined and sufficient clinical experience has not yet been gathered to support the validity of these MIC breakpoints.

An abbreviated scheme for identification of Yersinia enterocolitica isolated from food enrichments on CIN (cefsulodin-irgasan-novobiocin) agar

An abbreviated procedure for the biochemical identification of Yersinia enterocolitica isolated from food enrichments on CIN (cefsulodin-irgasan-novobiocin) agar was investigated. A total of 170 colonies resembling Y. enterocolitica in colonial morphology and appearance on CIN agar were selected for identification using API strips. Ninety-three of these isolates were examined with the PathoTec ornithine decarboxylase, Voges-Proskauer, and urease test strips. The PathoTec urease strip alone was adequate for identification of all isolates of Y. enterocolitica. Christensen's urea agar was applied to the remaining 77 isolates and found less specific in the 1 isolate of Enterobacter agglomerans was urease positive along with 10 isolates of Y. enterocolitica. CIN agar is a highly specific medium for isolation of Y. enterocolitica, requiring only Kligler iron agar and urea slants for confirmation of presumptive colonies.

Interstitial fluid concentrations of cefsulodin, azlocillin and carbenicillin

Cefsulodin, azlocillin and carbenicillin were administered by intramuscular injection to rats in a dose of 100 mg/kg. THe serum concentration in frequent samples after administration was determined and compared with the interstitial fluid (IF) concentration, measured with implanted paper discs enveloped in a dialysis tube. The IF concentration of cefsulodin was significantly higher than that of the other two antibiotics. The AUC in the IF was also larger for cefsulodin.