Cefamandole, a cephalosporin antibiotic with an unusually wide spectrum of activity

Identification of key genes and pathways in chronic rhinosinusitis with nasal polyps and asthma comorbidity using bioinformatics approaches

Patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and asthma comorbidity (ACRSwNP) present severe symptoms and are more likely to relapse. However, the pathogenesis of ACRSwNP is not fully understood. The aim of this study was to explore the underlying pathogenesis of ACRSwNP using bioinformatics approaches. ACRSwNP-related differentially expressed genes (DEGs) were identified by the analysis of the GSE23552 dataset. The clusterProfiler R package was used to carry out functional and pathway enrichment analysis. A protein–protein interaction (PPI) network was built using the STRING database to explore key genes in the pathogenesis of ACRSwNP. The bioinformatics analysis results were verified through qRT-PCR. The Connectivity Map (CMap) database was used to predict potential drugs for the treatment of ACRSwNP. A total of 36 DEGs were identified, which were mainly enriched in terms of regulation of immune response and detection sensory perception of taste. Thirteen hub genes including AZGP1, AQP9, GAPT, PIP, and PRR4 were identified as potential hub genes in ACRSwNP from the PPI network. Analysis of the GSE41861 dataset showed that upregulation of CST1 in nasal mucosa was associated with asthma. qRT-PCR detection confirmed the bioinformatics analysis results. Tacrolimus and spaglumic acid were identified as potential drugs for the treatment of ACRSwNP from the CMap database. The findings of this study provide insights into the pathogenesis of ACRSwNP and may provide a basis for the discovery of effective therapeutic modalities for ACRSwNP.

The Chemical Relationship Among Beta-Lactam Antibiotics and Potential Impacts on Reactivity and Decomposition

Beta-lactam antibiotics remain one of the most commonly prescribed drug classes, but they are limited by their propensity to cause hypersensitivity reactions (e.g., from allergy to anaphylaxis) as well as by the emergence of bacteria with a myriad of resistance mechanisms such as β-lactamases. While development efforts continue to focus on overcoming resistance, there are ongoing concerns regarding cross-contamination of β-lactams during manufacturing and compounding of these drugs. Additionally, there is a need to reduce levels of drugs such as β-lactam antibiotics in waste-water to mitigate the risk of environmental exposure. To help address future development of effective remediation chemistries and processes, it is desired to better understand the structural relationship among the most common β-lactams. This study includes the creation of a class-wide structural ordering of the entire β-lactam series, including both United States Food and Drug Association (US-FDA)-approved drugs and experimental therapies. The result is a structural relational map: the "Lactamome," which positions each substance according to architecture and chemical end-group. We utilized a novel method to compare the structural relationships of β-lactam antibiotics among the radial cladogram and describe the positioning with respect to efficacy, resistance to hydrolysis, reported hypersensitivity, and Woodward height. The resulting classification scheme may help with the development of broad-spectrum treatments that reduce the risk of occupational exposure and negative environmental impacts, assist practitioners with avoiding adverse patient reactions, and help direct future drug research.

Soil Salinity and pH Drive Soil Bacterial Community Composition and Diversity Along a Lateritic Slope in the Avon River Critical Zone Observatory, Western Australia

Soils are crucial in regulating ecosystem processes, such as nutrient cycling, and supporting plant growth. To a large extent, these functions are carried out by highly diverse and dynamic soil microbiomes that are in turn governed by numerous environmental factors including weathering profile and vegetation. In this study, we investigate geophysical and vegetation effects on the microbial communities of iron-rich lateritic soils in the highly weathered landscapes of Western Australia (WA). The study site was a lateritic hillslope in southwestern Australia, where gradual erosion of the duricrust has resulted in the exposure of the different weathering zones. High-throughput amplicon sequencing of the 16S rRNA gene was used to investigate soil bacterial community diversity, composition and functioning. We predicted that shifts in the microbial community would reflect variations in certain edaphic properties associated with the different layers of the lateritic profile and vegetation cover. Our results supported this hypothesis, with electrical conductivity, pH and clay content having the strongest correlation with beta diversity, and many of the differentially abundant taxa belonging to the phyla Actinobacteria and Proteobacteria. Soil water repellence, which is associated with Eucalyptus vegetation, also affected beta diversity. This enhanced understanding of the natural system could help to improve future crop management in WA since the physicochemical properties of the agricultural soils in this region are inherited from laterites via the weathering and pedogenesis processes.

Nanotechnology solutions to restore antibiotic activity

This review focuses on the development of nanoparticle systems that enables to enhance and restore the antibiotic activity for drug-resistant organisms. New and more aggressive antibiotic resistant bacteria and parasites calls for the development of new therapeutic strategies to overcome the inefficiency of conventional antibiotics and bypass treatment limitations related to these pathologies. Nanostructured biomaterials, nanoparticles in particular, have unique physicochemical properties such as ultra-small and controllable size, large surface area to mass ratio, high reactivity, and functionalizable structure. These properties can be applied to facilitate the administration of antimicrobial drugs, thereby overcoming some of the limitations in traditional antimicrobial therapeutics. Here the current progress and challenges in synthesizing nanoparticle platforms for restoring activity of various antimicrobial drugs are reviewed with an emphasis on antibiotics. We also call attention to the need to unite the shared interest between nanoengineers and microbiologists in developing nanotechnology for the treatment of microbial diseases.

Concentration of cefamandole in plasma and tissues of patients undergoing cardiac surgery: the influence of different cefamandole dosage

OBJECTIVE

To develop an improved regimen of antibiotic prophylaxis in cardiac surgery, three antibiotic prophylactic regimens for patients scheduled to have elective cardiothoracic surgery involving a median sternotomy were evaluated.

DESIGN

A prospective, randomized, unblinded study.

SETTING

A university teaching hospital.

PARTICIPANTS

Sixty-nine men scheduled for elective coronary artery bypass grafting (CABG) with extracorporeal circulation (ECC) were included in the study.

INTERVENTIONS

The patients were selected at random to receive 2 g of cefamandole (CM) at induction of anesthesia (group 1, n = 24), or 2 g of CM at the beginning of anesthesia followed by an additional dose (2 g) immediately after onset of cardiopulmonary bypass (CPB) (group 2, n = 22), or 4 g of CM just at the initiation of anesthesia (group 3, n = 23). Samples from the mammary artery, sternum, and plasma were obtained at various intervals after injection of the antibiotic (10 minutes intravenously) to compare antibiotic levels, assayed for CM concentrations, with high-pressure liquid chromatography (HPLC) and plasma bactericidal activity as well as infectious complications in these sites as a function of time for the three groups.

MEASUREMENTS AND MAIN RESULTS

There were no significant differences in biometric data, duration of hospitalization, or management of cardiopulmonary bypass, including urinary tract drainage and infusion volume. The mean plasma t1/2 (distributive or alpha-phase) before bypass was 51.7 +/- 16.7 minutes for group 1 and 2 patients and 54.9 +/- 15.9 minutes for group 3 patients. CM plasma values were significantly higher in group 2 (170.3 +/- 105.8 micrograms/mL) than in groups 1 and 3 (111.8 +/- 42.2 micrograms/mL, 101.2 +/- 57.2 micrograms/mL) at the end of bypass periods (p < 0.05). The antibiotic contents of mammary artery and sternum samples of group 2 (15.6 +/- 4.7 micrograms/mL, 9.5 +/- 4.7 micrograms/mL) were significantly higher after completion of CPB compared with group 1 (5.7 +/- 1.9 micrograms/mL, 3.8 +/- 2.9 micrograms/mL) and group 3 (6.3 +/- 3.5 micrograms/mL, 3.6 +/- 1.8 micrograms/mL) (p < 0.05). There were no significant differences in distribution of micro-organisms among the three groups, but two patients of groups 1 and 3 with plasma and tissue CM levels below minimal inhibitor concentration (MIC90) for Hemophilus influencea, E coli, Proteus ssp and Klebsiella ssp after completion of CPB, respectively, developed a pneumonia postoperatively caused by Hemophilus influencea (1), E coli (1) and Klebsiella ssp (2) (p < 0.05).

CONCLUSIONS

It would be preferable to infuse the antibiotic shortly before the operative procedure. However, to keep tissue and plasma CM values more than MIC90 for common pathogens during the time period studied, a second infusion of 2 g of CM administered after onset of CPB suggests better protection against the risk of microbial infections. Therefore, the findings might be important for the choice of antibiotic prophylaxis, particularly for high-risk patients.

Cefamandole pharmacokinetics during standard and pulsatile cardiopulmonary bypass

The pharmacokinetics of cefamandole during standard or pulsatile cardiopulmonary bypass were studied in 13 adult cardiac surgery patients. All patients received 20 mg/kg of cefamandole intravenously at midnight before surgery, 6 AM on the morning of surgery and just prior to the initiation of cardiopulmonary bypass (CPB) surgery. Serum, skeletal muscle, and fat samples were taken at the beginning of CPB and at 30-minute intervals thereafter and assayed for cefamandole concentration. The average elimination rate constant and elimination half-life for cefamandole in patients undergoing standard CPB were 0.73 +/- 0.09 hour-1 and 0.94 +/- 0.11 hour, respectively. In contrast patients undergoing pulsatile CPB had significantly slower elimination rate constants (0.50 +/- 0.1 hour-1 and 1.4 +/- 0.28 hours, respectively; P less than or equal to .05). Area under the curve (AUC) values for cefamandole in fat and muscle tissue were higher in patients undergoing pulsatile CPB, but the differences were not statistically significant. Prolonged elimination from the serum, skeletal muscle, and adipose tissue, as compared with normal subjects, is seen with both pulsatile and standard CPB but is greater for the pulsatile method. Intraoperative dosing of cefamandole is required to maintain adequate serum and tissue levels for operations lasting longer than 4 or 6 hours in which standard or pulsatile CPB, respectively, are used.

Two-day cefamandole versus five-day cephazolin prophylaxis in 965 total hip replacements. Report of a multicentre double blind randomised trial

The aim of this trial was to compare a 5-day course of cephazolin with a regimen of 2 days of cefamandole in 965 total hip replacements (488 in the cefamandole group and 477 in the cephazolin group). The effect of the prophylactic antibiotic on the bacterial colonization of drains (mean duration of drainage: 3.2 +/- 0.3 days) and on the susceptibility of colonizing organisms was assessed. No significant difference was observed in the percentage of infected drains between the two groups. The cefamandole group had a lower rate of Gram-negative organisms (23% versus 44%, p less than 0.01). The rate of deep infections within one year after operation was 0.7% in the cefamandole group versus 0.5% in the cephazolin group, and the difference is not significant. Cefamandole given for two days appears to be an effective prophylaxis against sepsis in total hip replacements.

Emergence of coagulase negative staphylococci as major nosocomial bloodstream pathogens

Over an eight year period, 1975 to 1982, 1,843 nosocomial bloodstream infections were identified by routine prospective surveillance at the University of Virginia Hospital (106/10,000 admissions). Despite a decline in overall bloodstream infection rates during the study period (P = .085), bloodstream infections due to gram positive organisms increased from 29 (1975-1978) to 43/10,000 (1979-1982), (P less than 0.001). Notably, rates for coagulase negative staphylococci increased from 5.2 (1975-1978) to 12.4/10,000 (1979-1982), (P less than 0.001). In 1982, coagulase negative staphylococci accounted for 17% of all bloodstream infections and were the most frequently isolated pathogens. Sixty-four percent of patients with coagulase negative staphylococci were in critical care units versus 41% with other bloodstream infections (P less than .05). The recognition of coagulase negative staphylococci as significant bloodstream pathogens markedly alters the clinician's approach to nosocomial septicemia.

Classification of cephalosporins

Many cephalosporins are now in clinical use. They have a wide range of activity against different species of bacteria and also differ in their pharmacokinetic and metabolic characteristics. This article outlines a basis for comparison and classification of cephalosporins into 4 groups active mainly against: (1) Gram-positive bacteria; (2) Gram-negative rods; (3) Gram-negative rods including Pseudomonas spp.; and (4) Gram-negative rods including Bacteroides spp. Further subdivisions highlight the pharmacological differences.

Disposition kinetics of cefamandole during continuous ambulatory peritoneal dialysis

Cefamandole disposition kinetics were examined in six male subjects with renal impairment who were undergoing continuous ambulatory peritoneal dialysis. Creatinine clearance values ranged from less than 1 to 11 ml/min. Cefamandole was given as a 1-g intravenous dose infused over 30 min. Cefamandole concentrations were determined in serum, urine, and dialysis fluid by a high-performance liquid chromatographic method. The following average parameter values were obtained (range): half-life, 6.1 h (4.6 to 9.7); systemic clearance, 21.9 ml/min (8.4 to 35.5); renal clearance, 11.5 ml/min (0.03 to 22.3); dialysis clearance, 0.92 ml/min (0.7 to 1.3); nonrenal clearance, 12.2 ml/min (2.9 to 27.0); volume of distribution, 0.18 liter/kg (0.09 to 0.25); steady-state volume of distribution, 0.17 liter/kg (0.09 to 0.24). Approximately 5% of the dose was dialyzed (range, 2.8 to 8.3), indicating that there is no need to supplement a dosing regimen of cefamandole due to loss by dialysis. There was a positive correlation between creatinine clearance and the terminal elimination rate constant of cefamandole (r2 = 0.41) and cefamandole renal clearance (r2 = 0.83).

Comparison of ceftazidime with cefamandole for therapy of community-acquired pneumonia

Ceftazidime and cefamandole were compared in the treatment of pneumonia. The median MIC of ceftazidime for all Streptococcus pneumoniae (n = 17) and Haemophilus influenzae (n = 10) isolates was 0.125 microgram/ml. All other isolates were inhibited by less than 0.5 microgram of ceftazidime per ml, with the exception of a group B streptococcus (MIC = 4 micrograms/ml). Satisfactory clinical responses were observed in 91% (20 of 22) of cefamandole-treated patients and 85% (17 of 20) of ceftazidime-treated patients.

The pharmacokinetics of antibiotics used to treat peritoneal dialysis-associated peritonitis

Antibiotics continue to be used frequently to treat CAPD-associated peritonitis. Selection of appropriate antibiotic doses and routes of administration has been based largely upon clinical experience. Early pharmacokinetic studies utilized patients being treated with IPD. The relevance of these studies to CAPD remains unknown. Little information exists on the effects of peritonitis on peritoneal drug transport. Until the effects of peritonitis during CAPD are better understood, pharmacokinetic data will be of limited value in designing specific treatment recommendations for this common complication of peritoneal dialysis.

Treatment of osteomyelitis and septic arthritis with cefamandole

Fourteen patients with bone and joint infections caused by a variety of bacterial pathogens were treated with intravenous cefamandole, 4 to 12 g/day; ten received additional therapy with 2 g/day of cefaclor and one with 2 g/day of cephalexin. Ten of 14 patients were cured. Of those cured, infecting pathogens had minimal inhibitory concentrations of cefamandole of 4 micrograms or less/ml. Of those who were not cured, two had recurrent infections that had not responded to other previously administered antibiotics, one had a mixed infection with resistant strains, and one had positive bone cultures five months after a favorable clinical response. Peak and valley cefamandole serum concentrations were 48.0 to 173.0 micrograms/ml and 23.4 micrograms or less/ml, respectively. Synovial fluid concentrations were 11.1 to 16.7 micrograms/ml and bone concentrations were 0.2 to 20.4 micrograms/g. Adverse effects included leukopenia in one and hepatic enzyme elevations in four patients. Cefamandole, with and without cefaclor, was efficacious in therapy of bone and joint infections caused by susceptible organisms.

Pre-incisional intraparietal injection of cephamandole: a new approach to wound infection prophylaxis

Pre-incisional injection of cephamandole has been studied. Wound tissue levels of cephamandole have been found to be extremely high throughout the operation. Serum levels were compared to those obtained with parenterally administered antibiotic. The use of a pre-incisional injection of antibiotic therefore offers major theoretical advantages over the use of either conventional parenteral or topical antibiotics in the prevention of postoperative sepsis.

Antibacterial activity and beta-lactamase stability of ceftazidime, an aminothiazolyl cephalosporin potentially active against Pseudomonas aeruginosa

The in vitro activity and beta-lactamase stability of ceftazidime were evaluated against 700 gram-positive and gram-negative bacteria. Ceftazidime was less active than penicillins or older cephalosporins against Staphylococcus spp. and Streptococcus spp., and it did not inhibit Streptococcus faecalis, Listeria, or anaerobic species. Ceftazidime was as active as ceftizoxime and moxalactam and more active than cefoperazone against Escherichia coli. Klebsiella, and Proteus mirabilis with minimal inhibitory concentrations of less than 0.2 mg/liter. Ceftazidime also inhibited Enterobacter, Citrobacter, Salmonella, and Shigella at concentrations below 0.2 mg/liter. Most Morganella, Proteus rettgeri, Proteus vulgaris, and Proteus inconstans were inhibited at concentrations below 1 mg/liter, similar to the concentrations for moxalactam, ceftizoxime, and cefotaxime. Ceftazidime was the most active agent tested against Pseudomonas aeruginosa, with a mean minimal inhibitory concentration of 1.6 mg/liter. It inhibited carbenicillin-, piperacillin-, cefoperazone-, and cefsulodin-resistant Pseudomonas. Minimal inhibitory and minimal bactericidal concentrations were similar, with the exception of some Pseudomonas values at 10(7) colony-forming units. Use of different media did not alter minimal inhibitory concentration values. Ceftazidime was not hydrolyzed by staphylococcal beta-lactamase or plasmid beta-lactamase of the TEM-1, TEM-2, SHV-1, OXA-1, PSE-1, PSE-2 types or by inducible beta-lactamases of the cephalosporinase type. Ceftazidime provides an extremely active agent against aerobic and facultative gram-negative bacteria.

Use of cefamandole in the treatment of soft tissue and skeletal infections

In review of our data, 12 of 38 patients (31.5 percent) had adverse drug reactions, a somewhat bothersome factor. Disturbing side effects of leukopenia and pancytopenia were seen in two patients, respectively, who were receiving cefamandole 12 g/d. Other cephalosporins, including cephalothin and cefazolin, have been reported to cause leukopenia. Eosinophilia and elevations of alkaline phosphatase and SGOT levels were noted with other cephalosporins. We observed no adverse clinical reactions associated with these findings. Although our study was able to demonstrate the therapeutic effectiveness of cefamandole in the treatment of soft tissue and skeletal infections, it should be reemphasized that cefamandole should be used only as an alternative treatment for the penicillin-allergic patient. In reality, a first-generation cephalosporin should be used for gram-positive organisms if one is required in soft tissue infections.

Cefamandole preparation for colonic surgery

A controlled, prospective, randomized study of 457 patients undergoing colonic surgery was done to compare systemic cefamandole therapy to neomycin-erythromycin in reducing postoperative septic complications. Parenteral cefamandole and cephalothin were given before, during, and after surgery to achieve maximal antimicrobial coverage in the blood, tissues, peritoneum, and urine. Such protection is not obtained with oral antibiotic preparation. Major surgical indications were carcinoma in 216 patients and diverticulitis in 107 patients. More than half the patients had colonic perforations, obstruction, or fistulas. All patients were operated upon by a single surgeon during 1975-1980. Cephalothin (151 patients), combined with neomycin-erythromycin, resulted in an 11.3 per cent rate of postoperative septic complications. Cefamandole treatment in 112 patients resulted in an 8.9 per cent postoperative infection rate compared with 16.3 per cent in 141 matched control patients.

Antibiotic treatment of acute shigellosis: failure of cefamandole compared with trimethoprim/ sulfamethoxazole and ampicillin

Intravenously administered ampicillin (AMP), trimethoprim-sulfamethoxazole (TMP-SMX) and cefamandole (CEF) were evaluated in 30 children with shigellosis: 11 children received AMP, 10 TMP-SMX, and 9 CEF for a maximum of five days. Discharge criteria included; afebrile greater than 12 hrs, less than 9 stools/day, absence of seizures, and adequate oral intake. AMP or TMP-SMX patients required significantly fewer median days to meet discharge criteria than those who received CEF. AMP and TMP-SMX patients had fewer median days with fever (one day each) compared with CEF (five days). On day five, 7 of 8 CEF, 3 of 10 AMP and 2 of 9 TMP-SMX treated patients remained culture positive. Inhibitory concentrations against all Shigella isolates from CEF patients all were less than or equal to 0.4 microgram CEF/ml. Intravenous TMP-SMX was equivalent to AMP in treatment of children with shigellosis, while CEF was ineffective despite in vitro activity. Clinical and bacteriologic responses were achieved with AMP and TMP-SMX in the majority of patients with less than 5 days of intravenous therapy.

Comparative in vitro studies of Ro 13-9904, a new cephalosporin derivative

The in vitro activity of Ro 13-9904, a new cephalosporin derivative, was compared with the activities of cephalothin, cefamandole, cefoxitin, cefotaxime, and moxalactam against 591 clinical isolates of gram-negative and gram-positive organisms. The spectra of activity and potency of Ro 13-9904 and cefotaxime were quite similar; they were the most active agents against Enterobacteriaceae, Streptococcus pyogenes, Haemophilus influenzae, Neisseria gonorrhoeae, and Neisseria meningitidis. Moxalactam was only slightly less active against these organisms. Ro 13-9904, cefotaxime, and moxalactam were approximately equal in activity against Pseudomonas aeruginosa; concentrations of 50 to 100 microgram/ml inhibited over 90% of the strains tested. Cefamandole and cephalothin were the most active drugs tested against staphylococci. Moxalactam demonstrated the highest intrinsic activity against Bacteroides fragilis; a concentration of 1.6 microgram/ml inhibited over 50% of the strains. All six of the antibiotics were essentially inactive against group D streptococci. The action of all of the antibiotics was bactericidal, with minimal bactericidal concentrations generally being no more than twofold greater than minimal inhibitory concentrations. The only exception to this was found when large inocula of Staphylococcus aureus were tested. Increased inoculum size generally sharply reduced the activity of Ro 13-9904, cefotaxime, and moxalactam against Enterobacteriaceae and P. aeruginosa.

Purification and biochemical properties of beta-lactamase produced by Proteus rettgeri

beta-Lactamase produced by Proteus rettgeri was found to be a typical cephalosporin beta-lactamase on the basis of its substrate hydrolysis profile. The enzyme activity was enhanced by prior treatment with an inducer. The enzyme was purified 166-fold by carboxymethyl-Sephadex column chromatography which indicated that its molecular weight was 42,000 +/- 2,000 and its isoelectric point was 8.7. Cefoperazone, cefoxitin, cefusulodin, cefmetazole, cefotaxime, 6059-S, FK749, YM-09330, carbenicillin, and cloxacillin were stable to this enzyme and possessed the function of competitive inhibition, as shown by their affinity for the beta-lactamase. The enzyme activity was inhibited by iodine, p-chloromerburibenzoate, and HG2+ ion. Clavulanic acid and CP-45899 displayed poor inhibitory activity toward this enzyme. The optimal pH was 8.0, and the optimal temperature was 50 degrees C.

Evaluation of cefamandole susceptibility testing of Enterobacteriacea by the autobac 1 system

A total of 509 clinical isolates of Enterobacteriaceae were tested for susceptibility to cefamandole by Autobac 1 and Bauer-Kirby disk diffusion methods, using commercially available 30-micrograms cefamandole disks. Minimal inhibitory concentrations were determined for all organisms showing major or very major discrepancies. Overall agreement between Autobac 1 and disk diffusion was 89.8%, with 5.1% major or very major and 5.1% minor discrepancies. When considering only the genera for which 20 or more isolates were tested, overall agreement was 90.8%. Discrepancies for Escherichia coli showed a trend toward resistance by Autobac 1, with minimal inhibitory concentrations generally in agreement with disk diffusion results. No trends were detected for other genera. The rate of agreement was lower for Enterobacter species (75.4%), but minimal inhibitory concentrations, determined for all discrepancies in this genus, agreed with Autobafc 1 as often a with disk diffusion results.

High-dose cefamandole therapy in obstetric and gynecologic infections

Increased understanding of bacterial infections of the pelvis has led to the frequent administration of double and triple antimicrobial chemotherapy for polymicrobial infections in hospitalized patients. This study evaluated the use of high-dose cefamandole as a single agent in the treatment of obstetric and gynecologic infections. Cefamandole was administered by intravenous infusion of 2 gm every 4 hours or, less often, every 3 hours. Twenty patients were entered into the study, 11 with postpartum endometritis and nine with pelvic inflammatory disease. Seventeen of the 20 patients (85%) were successfully treated; all failures were in the endometritis group. The aerobic organisms and the gram-positive anaerobic organisms isolated from these infections were susceptible in vitro to cefamandole at attainable serum concentrations. The bacteroides isolated were more resistant. The data suggest that high-dose cefamandole therapy is effective as a single agent for the majority of moderate obstetric and gynecologic infections.

Antibacterial activity of ceftizoxime, a beta-lactamase-stable cephalosporin

The in vitro activity of ceftizoxime was compared with that of other beta-lactam antibiotics against 538 isolates. Ceftizoxime was the most active agent tested against Escherichia coli and Klebsiella, inhibiting 80% at 0.025 microgram/ml. It was more active than cefotaxime against Enterobacter cloacae and E. aerogenes. Ceftizoxime was more active than cefoxitin, cefotaxime, cefoperazone, and carbenicillin against Proteus mirabilis and indole-positive Proteus. It inhibited 97% of multiresistant Serratia isolates at 12.5 microgram/ml, whereas cefotaxime inhibited only 19%. Ceftizoxime was less active than cefotaxime and cefoperazone against Pseudomonas aeruginosa, but was more active than carbenicillin. It was more active than cefotaxime and cefoxitin against Bacteroides. It was not appreciably destroyed by beta-lactamases of Staphylococcus aureus, Enterobacteriaceae, or Pseudomonas.

Pharmacokinetics of cefamandole and ampicillin in experimental meningitis

The penetration of cefamandole and ampicillin into the cerebrospinal fluid of rabbits with and without pneumococcal meningitis was evaluated. In normal animals, a mean maximum concentration of 0.22 +/- 0.13 microgram of cefamandole per ml was measured in the spinal fluid after a dose of 150 mg/kg given intramuscularly; with 25 and 50 mg/kg doses, no antibiotic was detected in the cerebrospinal fluid. With ampicillin, in intramuscular doses of 200 and 300 mg/kg, the mean maximum concentrations encountered in the cerebrospinal fluid were 1.59 +/- 0.4 and 1.47 +/- 0.44 microgram/ml, respectively. Penetration of cefamandole, and to a lesser extent ampicillin, was increased after 24 h of experimental meningitis. With cefamandole, the concentration of drug in the cerebrospinal fluid exceeded the usual inhibitory concentration for Haemophilus influenzae only with the 150 mg/kg dose. After 48 h of meningitis, there was a trend toward higher levels of antibiotic in the cerebrospinal fluid, but the difference between animals infected 24 versus 48 h was not statistically significant. In animals with meningitis, serum concentrations after 150 mg of cefamandole per kg and both ampicillin doses studied were 32 to 38% lower than the serum levels achieved in normal rabbits after identical doses of antibiotic.

In vitro comparison of synergism between cefamandole and gentamicin or tobramycin by the triple layer agar method with enzymatic inactivation

A synergistic effect was shown with gentamicin and tobramycin by means of a triple layer agar technique and enzymatic inactivation of cefamandole after only four hours' incubation. When the strain is sensitive to cefamandole and aminoglycosides, synergy is observed against all the strains studied (Staphylococcus aureus, Proteus, Klebsiella, Escherichia coli, Enterobacter, and Haemophilus influenzae). No significant difference was noted between the cefamandole-tobramycin and the cefamandole-gentamicin combinations when the microbial strains were sensitive to the three antibiotics.

In vitro activity of LY127935

The activity of LY127935, a beta-lactam antibiotic of novel structure, was studied in vitro against facultative gram-negative bacilli, Staphylococcus aureus, and Bacteroides fragilis. The strains were recent clinical isolates, many of which were relatively resistant to other antibiotics. LY127935 exhibited striking activity against Escherichia coli, Klebsiella pneumoniae, Enterobacter sp., Proteus sp., Serratia marcescens, and B. fragilis with median minimum inhibitory concentrations of less than or equal to 1.0 micrograms/ml. It was somewhat less active against Pseudomonas aeruginosa and S. aureus. Cefotaxime (HR 756) showed very similar activity except that it was substantially weaker against B. fragilis. LY127935 was more active than cefamandole, cefoxitin, or piperacillin; it was also as potent as tobramycin or amikacin against all species except for P. aeruginosa.

Antibacterial activity of a new 1-oxa cephalosporin compared with that of other beta-lactam compounds

The in vitro activity of (6R,7R)-7-{[carboxy(4-hydroxyphenyl)acetyl]amino}-7-methoxy-3-[[(1-methyl -1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-oxa-1-azabicyclo-[4.2.0]oct-2-ene -2-carboxylic acid was tested against isolates of gram-positive and negative bacteria and compared with those of cephalothin, cefuroxime, cefamandole, cefoxitin, cefotaxime, and carbenicillin. The compound was less active than the other compounds when tested against Staphylococcus aureus and Staphylococcus epidermidis. It had equal or slightly less activity than did cefotaxime when tested against members of the Enterobacteriaceae, but was 8- to 32-fold more active than the other cephalosporins against the Enterobacteriaceae, inhibiting most isolates at concentrations less than 0.5 mug/ml. The compound was twofold more active than cefotaxime and cefoxitin against Bacteroides, and it was twofold more active than cefotaxime and fourfold more active than carbenicillin against Pseudomonas aeruginosa. In vitro activity did not correlate with either the presence or type of beta-lactamase in either Enterobacteriaceae or Pseudomonas. The compound showed minimal synergy when combined with aminoglycosides or carbenicillin.

Bacterial pneumonia in the elderly: a reappraisal of conventional therapy, with a note on cefamandole

Community-acquired bacterial pneumonia in the elderly has for years been attributed almost exclusively to Streptococcus pneumoniae. Recent technical advances have provided bacteriologic and epidemiologic data demonstrating that other pathogens are important causes of pulmonary infection in older patients. This report reviews these data and reappraises the conventional therapy of community-acquired bacterial pneumonia in geriatric patients. Some properties of a new antibiotic, cefamandole nafate, are described.

Comparative activity and beta-lactamase stability of cefoperazone, a piperazine cephalosporin

The in vitro activity and beta-lactamase stability of 7-[d(-)-alpha-(4-ethyl-2,3-dioxopiperazino-carbonylamino) -p-hydroxyphenylacetamido]-3-[(1-methyl)-5-tetrazolylthiomethyl] -Delta(3)-cephem-4-carboxylic acid (cefoperazone), a cephalosporin analog of piperacillin, were compared with the activities and stabilities of other cephalosporins and cephamycins. The compound was less active than cephalothin or cefamandole in inhibiting Staphylococcus aureus; it was as active as cefamandole and cefoxitin against most of the Enterobacteriaceae but less active than cefotaxime. It was more active than carbenicillin or piperacillin against Pseudomonas aeruginosa. In general, the compound was not active against Bacteroides. It was hydrolyzed by the beta-lactamases of some Escherichia coli which hydrolyzed cefamandole, but was stable to most plasmid-mediated, chromosomally mediated, inducible beta-lactamases in the Enterobacteriaceae and Pseudomonas.

Cefamandole pharmacokinetics and dosage adjustments in relation to renal function

The pharmacokinetic characteristics of cefamandole were determined after intravenous administration of a 1-Gm dose to 10 subjects with normal renal function, 10 patients with stabilized renal failure, and five chronic nephritic patients included in a intermittent hemodialysis program. In normal subjects, biological half-life (t1/2) averaged 0.94 hour, the overall elimination rate constant (Ke) was 0.7378 (hr-1), total clearance (Ct) was 223 ml/min/1.73 m2, renal clearance (Cr) was 164 ml/min/1.73 m2, and urine recovery of cefamandole over the 6 hours following a dose amounted to 74 per cent of the administered dose. In patients with stabilized renal failure and in patients on hemodialysis, biological half-life was markedly increased, with a theoretical value of 10.4 hours in case of a creatinine clearance of zero. The amount of antibiotic extracted over a 6-hour dialysis period accounted for 29 per cent of the cefamandole present in the vascular compartment at the beginning of the dialysis procedure. A significant correlation was established between the values of Ke and creatinine clearances, Ccr: Ke = 0.0289 + 0.0063Ccr (r = 0.937). This relationship was used to calculate the loading dose (LD), maintenance doses (D), and dosage intervals (tau) with regard to renal function. From these data recommendations regarding the adjustment of cefamandole dosage to the renal status can be made.

Emergence of resistance to cefamandole: possible role of cefoxitin-inducible beta-lactamases

Selection of resistance to cefamandole has been observed, and the drug has failed to protect animals lethally infected with certain Enterobacteriaceae that appeared to be highly susceptible in vitro. Using spectrophotometric assays, some of these organisms were found to produce beta-lactamases highly active against cefamandole. Cefoxitin, a poor enzyme substrate, was found to be superior to both cephalothin and cefamandole in induction of these enzymes. A simple disk induction test was developed and used to examine 147 Enterobacteriaceae for production of these beta-lactamases. The enzymes were found in 69% of cephalothin-resistant, cefamandole-susceptible strains and in only 3% of strains susceptible to both cephalothin and cefamandole. They were most prevalent among isolates of Enterobacter, indole-positive Proteus, and Serratia. Since selection of resistance and therapeutic failures have occurred most often among these genera, the relationship between presence of inducible enzymes and outcome of therapy should be examined further in humans.

Comparative penetration of various cephalosporins into inflammatory exudate

A rabbit sterile peritonitis model was used to determine the relative penetration of four cephalosporin antibiotics into exudate fluid. Male New Zealand white rabbits were given 120 ml of sterile saline intraperitoneally, and peritonitis developed over the following 8 h, with exudate fluid containing a mean of 17,188 granulocytes per mm(3) at 8 h. Each antibiotic was administered intramuscularly at a dose of 30 mg/kg 3 h after peritonitis was initiated, and serum and peritoneal concentrations were measured 0.5, 1, 2, and 4 h later. Cefamandole gave the highest mean peak serum level (26.8 mug/ml), and cephalothin, cephacetrile, and cephradine all gave peak serum levels between 13 and 15 mug/ml. When peak peritoneal exudate concentration was expressed as a percentage of peak serum concentration, cephradine developed 28.5% of the peak serum level, cephacetrile 27.7%, cephalothin 14.0%, and cefamandole 12.5%. These percentages of exudate penetration were inversely proportional to the degree of serum protein binding: cephradine 26.6%, cephacetrile 36.3%, cephalothin 50%, and cefamandole 88%.

Pharmacokinetics and safety of cefamandole in newborn infants

Cefamandole, a new parenteral cephalosporin antibiotic, was administered to 23 newborn infants with pustular skin infection due to Staphylococcus aureus for an average duration of 7.5 days. All the patients improved clinically. Elevation of serum glutamic oxaloacetic transaminase and eosinophilia were observed in nine infants each transiently during treatment. There were no abnormalities of renal functions and Coombs' test results remained negative. The levels of cefamandole in serum after either intravenous or intramuscular administration were higher and the mean life was longer than those previously reported in older infants, children, and adults.

Treatment of obstetric and gynecologic infections with cefamandole

Cefamandole nafate is a derivative of 7-aminocephalosporanic acid which has been shown to have good in vitro activity against aerobes traditionally susceptible to cephalosporins as well as many anaerobes, including B. fragilis. One hundred women with obstetric or gynecologic infections completed treatment with cefamandole: 53 had post-cesarean section infections: 24, acute pelvic inflammatory disease: 16, posthysterectomy cuff cellulitis/abscess; and seven, vulvar or abdominal wound abscess. Almost 90% of these women had either polymicrobial aerobic/anaerobic bacterial infections or an anaerobic infection alone. Ninety women responded to cefamandole alone; in 10 cases chloramphenicol was added, but in addition five of these women required surgical therapy for eradication of infection. Mild to severe phlebitis at the infusion site that responded to conservative therapy was demonstrated in 14 women. Of 312 bacterial isolates from these women, 89% were sensitive to cefamandole at 32 microgram/ml, an easily achievable serum level; 93% of anaerobic streptococci, the most common isolates, were sensitive at 32 microgram/ml. Also, 90% of all Bacteroides species were susceptible at 32 microgram/ml; 82% of B. fragilis were susceptible at this concentration. These data indicate that cefamandole is safe and effective for treatment of women with polymicrobial pelvic infections but that approximately 5% of these women will require surgical exploration in addition to antimicrobial administration.

Growth curves, microscopic morphology, and subcultures of beta-lactamase-positive and -negative Haemophilus influenzae under the influence of ampicillin and cefamandole

In contrast to the results obtained with ampicillin, the minimum inhibitory concentrations of cefamandole against Haemophilus influenzae were within the same range (0.5 to 1.5 mug/ml) whether or not the strains were beta-lactamase producers. The minimum bactericidal concentrations were somewhat higher for beta-lactamase-positive strains (6.4 mug/ml) than for negative strains (1.2 mug/ml). In a culture with high initial microbial density, monitored by recording optical densities, the addition of 10 mug of cefamandole per ml brought about rapid lysis of a beta-lactamase-negative strain. Observation of a beta-lactamase-positive strain revealed, in the early part of the growth curve, absence of lysis and an increase of biomass similar to that observed in a drug-free control curve. In contrast to the results obtained with ampicillin, the culture consisted uniformly of spherical forms, probably in the process of division, which were capable of generating colonies. When the microbial density exposed to cefamandole was increased still further, persistent bacillary forms were observed, and after 24 h hydrolysis had eliminated every trace of microbiologically active cefamandole.

In vitro activity and beta-lactamase stability of cefazaflur compared with those of beta-lactamase-stable cephalosporins

The in vitro activity of cefazaflur, a parenteral cephalosporin, was determined against 590 clinical isolates. Cefazaflur inhibited the majority of gram-positive cocci at concentrations below 1 mug/ml except for enterococci. The agent was as active as cefamandole or cefoxitin against most Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis. Although it inhibited a number of strains of Enterobacter, indole-positive Proteus, and Serratia resistant to cephalothin, it was much less active against these organisms than were cefamandole or cefoxitin.

Cefatrizine activity compared with that of other cephalosporins

Cefatrizine, a new orally administered cephalosporin, was tested against 400 clinical isolates. Cefatrizine had excellent activity against gram-positive cocci, inhibiting all except enterococci at minimal inhibitory concentrations below 1 mug/ml. Cefatrizine inhibited the majority of Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, and Salmonella at concentrations below 12.5 mug/ml. Although cefatrizine was not hydrolyzed by many beta-lactamases, it did not inhibit a number of strains of Enterobacter, Serratia, or indole-positive Proteus. Cefatrizine was more active than cephalothin or cephalexin against E. coli, Klebsiella, Enterobacter, Citrobacter, Salmonella, and Shigella. Its overall activity was less than that of cefoxitin against strains resistant to cephalothin, but its activity against cephalothin-susceptible strains was equivalent to that of cefamandole.

HR 756, a new cephalosporin active against gram-positive and gram-negative aerobic and anaerobic bacteria

The in vitro activity of HR 756, 7-[2-(2-amino-4-thiazolyl)-2-(Z)-(methoximino)acetamido] cephalosporanic acid, was investigated against 659 isolates. HR 756 inhibited Neisseria and Haemophilus species at concentrations similar to those needed with ampicillin. It inhibited beta-lactamase-producing N. gonorrhoeae and H. influenzae. HR 756 was the most active compound tested against members of the Enterobacteriaceae, inhibiting most isolates of Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Salmonella, Enterobacter, and Shigella at concentrations of less than 0.1 mug/ml. It was twice as active as carbenicillin against Pseudomonas aeruginosa and inhibited Bacteroides fragilis as well as cefoxitin. HR 756 killed E. coli, Staphylococcus aureus, and P. aeruginosa at rates similar to other beta-lactam antibiotics.