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Journal of Clinical Microbiology Jul 1981A multilaboratory in vitro study was carried out to determine disk diffusion susceptibility testing quality control limits for two new semisynthetic penicillins,...
A multilaboratory in vitro study was carried out to determine disk diffusion susceptibility testing quality control limits for two new semisynthetic penicillins, mezlocillin and piperacillin. Existing limits for carbenicillin and ampicillin were reevaluated. Multiple tests (which followed standards set by the National Committee for Clinical Laboratory Standards ASM-2 revised) were performed in nine laboratories by different technologists using disks and Mueller-Hinton agar from different manufacturers. Clinically significant differences between disks produced by different manufacturers were not noted. Inhibitory zone diameter measurements from all laboratories were analyzed, and upper and lower control limits were established by using the overall median +/-0.5 the median range of the individual laboratory measurements as determining parameters. Close agreement of the data in this study with the results of national proficiency testing and quality control programs for ampicillin and carbenicillin supports the validity of our approach to making initial recommendations for quality control guidelines for new antimicrobial agents.
Topics: Ampicillin; Carbenicillin; Escherichia coli; Mezlocillin; Microbial Sensitivity Tests; Penicillins; Piperacillin; Pseudomonas aeruginosa; Quality Control; Staphylococcus aureus
PubMed: 6455443
DOI: 10.1128/jcm.14.1.67-72.1981 -
Selective discharge of patients with acute myeloid leukemia during chemotherapy-induced neutropenia.American Journal of Hematology Jan 1996It is common practice for patients with acute myeloid leukemia (AML) to be observed in hospital during the entire nadir after intensive chemotherapy. In an attempt to...
PURPOSE
It is common practice for patients with acute myeloid leukemia (AML) to be observed in hospital during the entire nadir after intensive chemotherapy. In an attempt to lessen the likelihood of developing infections with hospital acquired pathogens, we usually discharge patients upon completion of chemotherapy and follow them as outpatients. They are readmitted if fever develops. We evaluated the feasibility and safety of this practice.
PATIENTS AND METHODS
We studied 29 patients with AML (median age 40 years, range 16-63) who were treated with intensive remission-induction and consolidation chemotherapy. Afebrile patients not receiving antibiotics were discharged immediately following chemotherapy and were followed every 3-4 days at the day care unit. Patients were instructed to return immediately if fever rose to 38.2 degrees C or a fever of 38 degrees C persisted for 2 hr. The 29 patients received a total of 86 courses. Following 50 courses, patients were discharged. These 50 ambulatory nadir periods (ANPs) were monitored.
RESULTS
Median WBC and platelet counts on discharge were 2,900 per cubic millimeter (range 300-8,300) and 137,000 per cubic millimeter (range 17,000-618,000), respectively. Mean traveling time from the hospital by car was 1.6 hr (range 15 min-3 hr). In three of the 50 ANPs (6%), patients were not readmitted during their entire nadir. During 47 of the ANPs, patients returned to the hospital (because of fever in 44 cases), a mean of 7.2 days (range 1.0-12.7 days) after discharge. In 45 ANPs, patients were readmitted in good general condition. Four patients had life-threatening complications. Two patients were admitted in septic shock due to delay in seeking admission, but rapidly recovered. Two other patients died, one of cardiogenic shock within 24 hr of readmission and one 24 days later. Only one of the 11 gram negative bacteria cultured was resistant to mezlocillin and gentamicin. After 45 ANPs, patients were discharged a mean of 12.2 days (range 5-42 days) following readmission. We estimate that approximately 383 hospital days were saved by this policy, a mean of 7.6 days per patient, representing 16% of total inpatient hospital days.
CONCLUSIONS
For AML patients who are reliable and without complicating medical conditions, selected discharge following chemotherapy is a low-risk practice and may reduce the incidence of infection with resistant hospital-acquired pathogens.
Topics: Acute Disease; Adult; Ambulatory Care; Antineoplastic Combined Chemotherapy Protocols; Bacterial Infections; Catheterization, Central Venous; Cross Infection; Cytarabine; Daunorubicin; Disease Susceptibility; Etoposide; Female; Fever; Humans; Leukemia, Myeloid; Male; Middle Aged; Mitoxantrone; Neutropenia; Patient Discharge; Safety; Treatment Outcome
PubMed: 8571934
DOI: 10.1002/(SICI)1096-8652(199601)51:1<26::AID-AJH5>3.0.CO;2-9 -
Antimicrobial Agents and Chemotherapy Oct 1988Hyperbilirubinemia is frequently observed in neonates, and serious neurological complications such as kernicterus can be precipitated when the concentration of...
Hyperbilirubinemia is frequently observed in neonates, and serious neurological complications such as kernicterus can be precipitated when the concentration of unconjugated bilirubin is abnormally increased. The administration of drugs which bind to albumin and compete with bilirubin can increase the possibility of such a complication. To test the bilirubin-displacing activity of pharmacological agents that are used with newborns, 52 antimicrobial agents were investigated in vitro. A glycine conjugate of salicylate, 2-hydroxybenzoylglycine, which is known to be present at elevated levels in newborns and has a potent bilirubin-displacing property, was used as a positive control agent. Pooled cord serum was used as a source of hyperbilirubinemic serum. A centrifugal ultrafiltration method with semipermeable cones was employed to determine the effects of potential bilirubin-displacing agents on the levels of total bilirubin. 2-Hydroxybenzoylglycine was demonstrated to be the most potent bilirubin-displacing agent. Antibiotics could be classified into four groups: high-level displacers (sulfisoxazole, sulfamethoxazole, dicloxacillin, cefoperazone, and ceftriaxone), intermediate-level displacers (moxalactam, nafcillin, and 14 others), low-level displacers (aztreonam, carbenicillin, and 11 others), and nondisplacers (mezlocillin, cefuroxime, kanamycin, and 15 others). It is concluded that the ultrafiltration method is a rapid and readily reproducible for the determination of bilirubin displacement and that antibiotics with a tendency to displace bilirubin should be avoided in jaundiced newborns whenever appropriate alternatives are available.
Topics: Anti-Bacterial Agents; Bilirubin; Binding, Competitive; Chromatography, High Pressure Liquid; Fetal Blood; Humans; In Vitro Techniques; Infant, Newborn; Jaundice, Neonatal; Protein Binding
PubMed: 3190184
DOI: 10.1128/AAC.32.10.1571 -
Journal of Clinical Microbiology May 1991More efficient and reproducible alternative methods of performing agar dilution susceptibility testing are desirable, particularly for anaerobic bacteria. Anaerobes... (Comparative Study)
Comparative Study
More efficient and reproducible alternative methods of performing agar dilution susceptibility testing are desirable, particularly for anaerobic bacteria. Anaerobes generally grow more reliably on solid media than they do in broth microdilution wells. A new method, the revised spiral gradient endpoint (SGE) method, was evaluated against the standard agar dilution (SAD) method by using a wide variety of anaerobic gram-negative bacilli (161 strains) and eight antimicrobial agents. For the SGE method, a spiral plater was used to set up a concentration gradient of an antimicrobial agent within an agar plate across which bacterial strains were inoculated as radial streaks. After incubation, the MIC of the antimicrobial agent was calculated from the radial endpoint location where bacterial growth ceased along the streak. The MICs for 90% of strains tested (in micrograms per milliliter) and the cumulative percentages of susceptible strains at the breakpoints for the SGE and SAD methods, respectively, and for all 161 strains were as follows: for metronidazole, 2 and 100 versus 2 and 100; for imipenem, 1 and 99 versus 0.5 and 98; for ampicillin-sulbactam, 8 and 97 versus 8 and 98; for clindamycin, 4 and 90 versus 4 and 91; for cefoxitin, 32 and 95 versus 32 and 95; for mezlocillin, 256 and 88 versus greater than 128 and 86; for ampicillin, greater than or equal to 256 and 51 versus greater than 64 and 51; and for penicillin (in units per milliliter), greater than or equal to 512 and 71 versus greater than 64 and 65. The excellent agreement of these data and the greater sensitivity reproducibility, and efficiency of the revised SGE method warrant further evaluations. Assuming that these advantages are confirmed, the revised SGE method should be a useful alternative test method when detailed susceptibility data are desired.
Topics: Agar; Drug Resistance, Microbial; Evaluation Studies as Topic; Gram-Negative Anaerobic Bacteria; Humans; Microbial Sensitivity Tests; Reproducibility of Results; Sensitivity and Specificity
PubMed: 2056064
DOI: 10.1128/jcm.29.5.975-979.1991 -
Antimicrobial Agents and Chemotherapy May 1984The pharmacokinetic properties of mezlocillin were evaluated in newborn infants. Mean peak and trough concentrations of drug in plasma, after 75 mg of mezlocillin per kg...
The pharmacokinetic properties of mezlocillin were evaluated in newborn infants. Mean peak and trough concentrations of drug in plasma, after 75 mg of mezlocillin per kg given intravenously, were 252 and 72 micrograms/ml, respectively, in infants who were less than 38 weeks gestation and less than or equal to 7 days old, compared with 139 and 9 micrograms/ml, respectively, in infants greater than or equal to 38 weeks gestation and greater than 7 days old. The mean elimination half-life values were from 4.5 h in preterm infants who were less than or equal to 7 days old to 1.8 h in term infants greater than or equal to 7 days old. Median peak and trough bactericidal titers of drug in plasma from neonates treated with mezlocillin were 1:8 and 1:4, respectively, against a resistant (minimal bactericidal concentration, 512 micrograms/ml) Escherichia coli strain and 1:64 and 1:32, respectively, against a susceptible (minimal bactericidal concentration, 2 micrograms/ml) E. coli strain. We propose a dosage schedule of 75 mg of mezlocillin per kg administered every 12 h to preterm (gestational age less than 38 weeks) infants less than or equal to 7 days old, every 8 h to preterm infants greater than 7 days old or term infants less than or equal to 7 days old, and every 6 h to term infants greater than 7 days old.
Topics: Female; Gentamicins; Humans; Infant, Newborn; Injections, Intramuscular; Injections, Intravenous; Kinetics; Mezlocillin; Microbial Sensitivity Tests; Models, Biological; Penicillin Resistance
PubMed: 6563875
DOI: 10.1128/AAC.25.5.556 -
Antimicrobial Agents and Chemotherapy Nov 1982The impacts of meningeal infection with Pseudomonas aeruginosa and route of drug administration on the penetration of azlocillin and mezlocillin into the cerebrospinal... (Comparative Study)
Comparative Study
Comparative penetration of azlocillin and mezlocillin into cerebrospinal fluid of normal rabbits and rabbits with experimentally induced Pseudomonas aeruginosa meningitis.
The impacts of meningeal infection with Pseudomonas aeruginosa and route of drug administration on the penetration of azlocillin and mezlocillin into the cerebrospinal fluid of rabbits were evaluated. The penetration of both agents was increased to a similar degree in rabbits with meningitis compared with normal rabbits. The increase in penetration was greater after intravenous administration than after intramuscular administration.
Topics: Animals; Anti-Bacterial Agents; Azlocillin; Meningitis; Mezlocillin; Penicillins; Pseudomonas Infections; Rabbits
PubMed: 6217786
DOI: 10.1128/AAC.22.5.909 -
Antimicrobial Agents and Chemotherapy Apr 1984The susceptibilities of 347 urine isolates of enterococci (Streptococcus faecalis, 44%; S. faecalis subsp. zymogenes, 37%; S. faecalis subsp. liquefaciens, 19%) to... (Comparative Study)
Comparative Study
The susceptibilities of 347 urine isolates of enterococci (Streptococcus faecalis, 44%; S. faecalis subsp. zymogenes, 37%; S. faecalis subsp. liquefaciens, 19%) to ampicillin, azlocillin, mezlocillin, piperacillin, vancomycin, gentamicin, erythromycin, rosaramicin, rifampin, rifampin plus trimethoprim (1:4), trimethoprim-sulfamethoxazole (1:20), and chloramphenicol were determined by the agar dilution technique. There were no significant differences in susceptibility to individual agents among the subspecies of S. faecalis. Azlocillin and mezlocillin (MIC for 90% of isolates, 0.78 micrograms/ml) and piperacillin, ampicillin, and vancomycin (MIC for 90% of isolates, 1.56 micrograms/ml) were the most active agents and were significantly more potent than the other reference antibiotics tested.
Topics: Anti-Bacterial Agents; Bacteriuria; Enterococcus faecalis; Humans; Microbial Sensitivity Tests; Streptococcal Infections
PubMed: 6428309
DOI: 10.1128/AAC.25.4.532 -
Antimicrobial Agents and Chemotherapy Aug 1979The in vitro activities of the new ureidopenicillins piperacillin, mezlocillin, azlocillin, and Bay k 4999 were compared with those of ampicillin and ticarcillin against... (Comparative Study)
Comparative Study
The in vitro activities of the new ureidopenicillins piperacillin, mezlocillin, azlocillin, and Bay k 4999 were compared with those of ampicillin and ticarcillin against 336 Enterobacteriaceae, 109 nonfermenters, 55 Neisseria, and 28 Haemophilus influenzae isolates. Bay k 4999 displayed the largest spectrum of activity and had lower minimal inhibitory concentrations than any of the other penicillins against all of the species tested. Piperacillin showed the same spectrum but was slightly less active than Bay k 4999; it was slightly more effective than mezlocillin against Enterobacteriaceae and fully as active as azlocillin against Pseudomonas. All ureidopenicillins were substantially more active than ampicillin and ticarcillin. Isolates highly resistant to ampicillin or ticarcillin were also less susceptible to the ureidopenicillins.
Topics: Ampicillin; Azlocillin; Gram-Negative Aerobic Bacteria; Imidazolidines; Microbial Sensitivity Tests; Penicillins; Ticarcillin
PubMed: 485123
DOI: 10.1128/AAC.16.2.115 -
Antimicrobial Agents and Chemotherapy Aug 1981Three new cephalosporins, ceftazidime, ceftizoxime, and cefotiam, were evaluated in vitro against clinical isolates, and their activities were compared with those of... (Comparative Study)
Comparative Study
Three new cephalosporins, ceftazidime, ceftizoxime, and cefotiam, were evaluated in vitro against clinical isolates, and their activities were compared with those of other cephalosporins, mezlocillin, and tobramycin. All three new cephalosporins were very active against gram-positive cocci (except enterococci), but mezlocillin was more active against Streptococcus ssp. Cefotiam and cefamandole were the most active antibiotics against Streptococcus aureus. Ceftazidime had broad-spectrum activity against all gram-negative bacilli tested, except Enterobacter spp. Ceftizoxime was active against all, except Enterobacter spp. and Pseudomonas aeruginosa. Although cefotiam was quite active against Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis, it was inactive against indole-positive Proteus spp., Serratia spp, and P. aeruginosa. The in vitro activity suggests that ceftazidime should prove useful as a broad-spectrum antibiotic, in those settings in which the most likely pathogens are gram-negative bacilli.
Topics: Bacteria; Cephalosporins; Microbial Sensitivity Tests
PubMed: 7283419
DOI: 10.1128/AAC.20.2.226 -
Antimicrobial Agents and Chemotherapy May 1988Although often dismissed as contaminants when isolated from blood cultures, Bacillus spp. are increasingly recognized as capable of causing serious systemic infections....
Although often dismissed as contaminants when isolated from blood cultures, Bacillus spp. are increasingly recognized as capable of causing serious systemic infections. As part of a clinical-microbiological study, 89 strains of Bacillus spp. isolated from clinical blood cultures between 1981 and 1985 had their species determined and were tested for antimicrobial agent susceptibility to 18 antibiotics. Species of isolates were determined by the API 50CH and API 20E systems. Bacillus cereus (54 strains) was the most common species isolated, followed by B. megaterium (13 strains), B. polymyxa (5 strains), B. pumilus (4 strains), B. subtilis (4 strains), B. circulans (3 strains), B. amyloliquefaciens (2 strains), B. licheniformis (1 strain), and Bacillus spp. (3 strains). Microdilution MIC susceptibility tests revealed all B. cereus strains to be susceptible to imipenem, vancomycin, chloramphenicol, gentamicin, and ciprofloxacin. Non-B. cereus strains were most susceptible to imipenem, vancomycin, LY146032, and ciprofloxacin. Disk susceptibility testing suggested that B. cereus was rarely susceptible to penicillins, semisynthetic penicillins, or cephalosporins with the exception of mezlocillin. In contrast, many non-B. cereus strains were susceptible to penicillins, semisynthetic penicillins, and cephalosporins, but marked variability was noted among species.
Topics: Anti-Bacterial Agents; Bacillus; Humans; Microbial Sensitivity Tests; Retrospective Studies; Sepsis
PubMed: 3395100
DOI: 10.1128/AAC.32.5.642