Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Piperacillin”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources

Prospective randomized comparison of imipenem-cilastatin and piperacillin-tazobactam in nosocomial pneumonia or peritonitis.

Nosocomial pneumonia and acute peritonitis may be caused by a wide array of pathogens, and combination therapy is often recommended. We have previously shown that imipenem-cilastatin monotherapy was as efficacious as the combination of imipenem-cilastatin plus netilmicin in these two settings. The efficacy of imipenem-cilastatin is now compared to that of piperacillin-tazobactam as monotherapy in patients with nosocomial pneumonia or acute peritonitis. Three hundred seventy one patients with nosocomial pneumonia or peritonitis were randomly assigned to receive either imipenem-cilastatin (0.5 g four times a day) or piperacillin-tazobactam (4.5 g three times a day). Three hundred thirteen were assessable (154 with nosocomial pneumonia and 159 with peritonitis). For nosocomial pneumonia, clinical-failure rates in the piperacillin-tazobactam group (13 of 75 [17%]) and in the imipenem-cilastatin group (23 of 79 [29%]) were similar (P = 0.09), as were the numbers of deaths due to infection (6 in the imipenem-cilastatin group [8%], 7 in the piperacillin-tazobactam group [9%]) (P = 0.78). For acute peritonitis, clinical success rates were comparable (piperacillin-tazobactam, 72 of 76 [95%]; imipenem-cilastatin, 77 of 83 [93%]). For infections due to Pseudomonas aeruginosa, 45 patients had nosocomial pneumonia (21 in the piperacillin-tazobactam group and 24 in the imipenem-cilastatin group) and 10 had peritonitis (5 in each group). In the patients with nosocomial pneumonia, clinical failure was less frequent in the piperacillin-tazobactam group (2 of 21 [10%]) than in the imipenem-cilastatin [corrected] group (12 of 24 [50%]) (P = 0.004). Bacterial resistance to allocated regimen was the main cause of clinical failure (1 in the piperacillin-tazobactam group and 12 in the imipenem-cilastatin group). For the patients with peritonitis, no difference in clinical outcome was observed (five of five cured in each group). The overall frequencies of adverse events related to treatment in the two groups were similar (24 in the piperacillin-tazobactam group, 22 in the imipenem-cilastatin group). Diarrhea was significantly more frequent in the piperacillin-tazobactam group (10 of 24) than in the imipenem-cilastatin group (2 of 22). This study suggests that piperacillin-tazobactam monotherapy is at least as effective and safe as imipenem-cilastatin monotherapy in the treatment of nosocomial pneumonia or peritonitis. In P. aeruginosa pneumonia, piperacillin-tazobactam achieved a better clinical efficacy than imipenem-cilastatin, due to reduced development of microbiological resistance. Tolerance was comparable, with the exception of diarrhea, which was more frequent with piperacillin-tazobactam.

Acute Disease↗

Piperacillin-tazobactam for Pseudomonas aeruginosa infection: clinical implications of an extended-infusion dosing strategy.

BACKGROUND: Piperacillin-tazobactam is frequently used to treat Pseudomonas aeruginosa infections in critically ill patients. In an effort to improve clinical outcomes, an extended-infusion dosing scheme for piperacillin-tazobactam therapy was devised using a Monte Carlo simulation and was adopted into clinical practice at Albany Medical Center (Albany, New York). This study evaluates the clinical implications of extended infusion of piperacillin-tazobactam therapy for critically ill patients with P. aeruginosa infection. METHODS: We performed a cohort study of patients who received piperacillin-tazobactam therapy for a P. aeruginosa infection that was susceptible to piperacillin-tazobactam during the period January 2000-June 2004. Prior to February 2002, all patients received intermittent infusions of piperacillin-tazobactam (3.375 g intravenously for 30 min every 4 or 6 h); after this time, all patients received extended infusions of piperacillin-tazobactam (3.375 g intravenously for 4 h every 8 h). Data on demographic characteristics, disease severity, and microbiology were collected, and outcomes were compared between groups. RESULTS: A total of 194 patients comprised the 2 study groups: 102 patients received extended infusions of piperacillin-tazobactam, and 92 patients received intermittent infusions of piperacillin-tazobactam. No differences in baseline clinical characteristics were noted between the 2 groups. Among patients with Acute Physiological and Chronic Health Evaluation-II scores > or =17, 14-day mortality rate was significantly lower among patients who received extended-infusion therapy than among patients who received intermittent-infusion therapy (12.2% vs. 31.6%, respectively; P=.04), and median duration of hospital stay after collection of samples for culture was significantly shorter for patients who received extended-infusion therapy than for patients who received intermittent-infusion therapy (21 days vs. 38 days; P=.02).Conclusions. These results indicate that extended-infusion piperacillin-tazobactam therapy is a suitable alternative to intermittent-infusion piperacillin-tazobactam therapy, and they strongly suggest that improved outcomes may be realized by administering extended-infusion piperacillin-tazobactam therapy to critically ill patients with P. aeruginosa infection.

APACHE↗

Pharmacokinetic and pharmacodynamic evaluation of two dosing regimens for piperacillin-tazobactam.

STUDY OBJECTIVE: To compare the pharmacokinetic and pharmacodynamic profiles of two dosing regimens for piperacillin-tazobactam against commonly encountered pathogens. The regimens compared were piperacillin 4.0 g-tazobactam 0.5 g administered every 8 hours, and piperacillin 3.0 g-tazobactam 0.375 g administered every 6 hours. DESIGN: Multiple-dose, open-label, randomized, crossover study. SETTING: Clinical research center at Hartford Hospital. SUBJECTS: Twelve healthy volunteers. INTERVENTION: The two dosing regimens for piperacillin-tazobactam were administered intravenously in crossover design. Blood was sampled after the third dose. MEASUREMENTS AND MAIN RESULTS: Drug concentrations were determined by a validated high-performance liquid chromatography assay. The percentage of time above minimum inhibitory concentration (%T>MIC) for piperacillin was calculated for a range of MIC values. The maximum concentration (Cmax), area under the concentration-time curve (AUC0-tau), and total clearance of piperacillin differed significantly between the two study regimens, as did the Cmax, AUC0-tau, volume of distribution, and total clearance of tazobactam (p<0.05). The piperacillin 4.0 g-tazobactam 0.5 g regimen provided 40-50% T>MIC for MIC values 8-16 microg/ml; a similar value for the piperacillin 3.0 g-tazobactam 0.375 g regimen was 16-32 microg/ml. CONCLUSION: Although statistically significant differences in the pharmacodynamic profile were noted for the regimens, both provide adequate T>MIC against commonly encountered pathogens considered susceptible to piperacillin-tazobactam. However, for treatment of Pseudomonas aeruginosa infection, combination therapy or higher-dosage regimens (e.g., piperacillin 3.0 g-tazobactam 0.375 g every 4 hours, piperacillin 4.0 g-tazobactam 0.5 g every 6 hours, or continuous-infusion piperacillin 12 g-tazobactam 1.5 g/day) may be a prudent option when full MIC data are unavailable.

Adolescent↗

[Piperacillin-amikacin combinations: killing curves].

Bactericidal activity as a function of time of piperacillin (PIP) and amikacin (AKN) alone and in combination was evaluated by killing curves technique on 23 clinical isolates: E. coli (6), K. pneumoniae (5), E. cloacae (6) and P. aeruginosa (6), for which the minimal inhibitory concentrations ranges of piperacillin were 0.25 to 64 mg/l and of amikacin 1 to 8 mg/l. For each species, the strains were chosen according to the most frequent phenotypes: beta-lactams susceptible, penicillinase (Pase), cephalosporinase (Case) and Pase + Case producers. Killing curves were carried out with the following concentrations (mg/l): piperacillin (2, 16, 64); amikacin (4, 8, 16); piperacillin (2) + amikacin (4); piperacillin (16) + amikacin (8); piperacillin (64) + amikacin (16). Antibiotic concentrations corresponded to pharmacokinetics and/or to critical values of piperacillin and amikacin. Bactericidal activity was defined as a 4 log 10 decrease in CFU/ml between 2 and 24 hours. When piperacillin (64) was combined with amikacin (16), the bactericidal effects were nearly the same as those with amikacin alone. But piperacillin (16) + amikacin (8) combination had bactericidal effect for the majority of strains (21/23) and it prevented for some of them the bacterial regrowth observed with amikacin alone at the same concentration. A bactericidal activity without regrowth (until the 24th hour) was obtained for 9 strains; 2 susceptible E. coli, 3 K. pneumoniae (chromosomal Pase producer) and 4 cefotaxime susceptible E. cloacae, with low dose combination piperacillin (2) + amikacin (4). Finally, only combinations piperacillin (64) + amikacin (16) or piperacillin (16) + amikacin (8) had bactericidal activity on 2 Ticarcillin-resistant P. aeruginosa, the two antibiotics being separatedly bacteriostatic.(ABSTRACT TRUNCATED AT 250 WORDS)

Amikacin↗

Influence of renal function on trough serum concentrations of piperacillin in intensive care unit patients.

OBJECTIVE: To explore the effects of renal function estimated by measured creatinine clearance (Cl(CR)) on trough serum concentration (C(min)) of piperacillin given to critically ill patients. DESIGN: Prospective observational study. SETTING: An intensive care unit and research ward in a university hospital. PATIENTS: Seventy critically ill patients, including 22 with severe trauma. INTERVENTIONS: All subjects received an intravenous infusion of piperacillin 4 g three times (n = 61) or four times (n = 9) per day. Piperacillin C(min) values were determined 24 h after treatment started and compared to the French breakpoint defining antibiotic susceptibility against Enterobacteriaceae (8 mg/l) or Pseudomonas sp. (16 mg/l). RESULTS: Median (range) piperacillin C(min) was 11.9 (< 1-156.3) mg/l, with a great variability among patients. Although the median value was close to the breakpoints, sub-therapeutic plasma levels were frequently observed. Piperacillin C(min) was lower than the breakpoint for Enterobacteriaceae in 37% of patients, and lower than the breakpoint for P. aeruginosa in 67% of them. A strong relationship was observed between piperacillin C(min) and Cl(CR): the higher the Cl(CR,) the lower the piperacillin C(min )in serum. For patients with a Cl(CR) < 50 ml/min, enough piperacillin C(min) was achieved in most patients with 12 g piperacillin per day. For patients with higher Cl(CR) values, a piperacillin daily dose of 16 g or more may be warranted. CONCLUSIONS: In critically ill patients, therapeutic monitoring must be part of the routine, and knowledge of Cl(CR) value may be useful for the choice of adequate initial piperacillin dosing.

Adolescent↗

Argentinean collaborative multicenter study on the in vitro comparative activity of piperacillin-tazobactam against selected bacterial isolates recovered from hospitalized patients.

The in vitro activity of piperacillin-tazobactam and several antibacterial drugs commonly used in Argentinean hospitals for the treatment of severe infections was determined against selected but consecutively isolated strains from clinical specimens recovered from hospitalized patients at 17 different hospitals from 9 Argentinean cities from different geographic areas during the period November 2001-March 2002. Out of 418 Enterobacteriaceae included in the Study 84% were susceptible to piperacillin-tazobactam. ESBLs putative producers were isolated at an extremely high rate since among those isolates obtained from patients with hospital acquired infections 56% of Klebsiella pneumoniae, 32% of Proteus mirabilis and 25% Escherichia coli were phenotypically considered as ESBLs producers Notably P.mirabilis is not considered by for screening for ESBL producers. ESBLs producers were 100% susceptible to imipenem and 70% were susceptible to piperacillin-tazobactam whereas more than 50% were resistant to levofloxacin. The isolates considered as amp C beta lactamase putative producers showed 99% susceptibility to carbapenems while 26.7% were resistant to piperacillin-tazobactam and 38.4% to levofloxacin. Noteworthy only 4% of the Enterobacteriaceae isolates were resistant to amikacin. Piperacillin-tazobactam was the most active agent against Pseudomonas aeruginosa isolates (MIC(90): 128 microg/ml; 78% susceptibility) but showed poor activity against Acinetobacter spp (MIC(90):>256 microg/ml; 21.7% susceptibility). Only 41.7% Acinetobacter spp isolates were susceptible to ampicillin-sulbactam. Piperacillin-tazobactam inhibited 100% of Haemophilus influenzae isolates (MIC(90) < 0.25 microg/ml) but only 16.6% of them were ampicillin resistant. The activity of piperacillin-tazobactam against oxacillin susceptible Staphylococcus aureus or coagulase negative staphylococci was excellent (MIC(90) 2 microg/ml; 100% susceptibility). Out of 150 enterococci 12 isolates (8%) were identified as E.faecium and only three isolates (2%), 2 E.faecium and 1 E.faecalis were vancomycin resistant. All the enterococci isolates were susceptible to linezolid. Piperacillin-tazobactam showed excellent activity (MIC(90) 2 microg/ml; 92% susceptibility). Regarding pneumococci all the isolates showed MICs of 16 microg/ml for piperacillin-tazobactam. Among 34 viridans group streptococci only 67% were penicillin susceptible and 85.2% ceftriaxone susceptible whereas piperacillin-tazobactam was very active (MIC(90) 4 microg/ml).Piperacillin-tazobactam is therefore a very interesting antibacterial drug to be used, preferably in combination (IE: amikacin-vancomycin) for the empiric treatment of severe infections occurring in hospitalized patients in Argentina. Caution must be taken for infections due to ESBL producers considering that the inoculum effect MICs can affect MIC values.

Adult↗

Piperacillin, a new penicillin active against many bacteria resistant to other penicillins.

The in vitro activity of piperacillin, a new semisynthetic piperazine penicillin derivative, was evaluated against 626 clinical isolates and compared with the activity of other beta-lactam antibiotics. At a concentration of 0.1 microgram/ml, piperacillin inhibited all streptococci except enterococci. Non-beta-lactamase-producing staphylococci were inhibited by 1.6 microgram or less per ml. Both beta-lactamase- and non-beta-lactamase-producing Haemophilus were inhibited by 0.1 microgram/ml. Piperacillin inhibited non-beta-lactamase-producing Escherichia coli, Salmonella, and Shigella at a concentration of 6.3 micrograms/ml, but 20% of strains of these species containing type III beta-lactamase were not inhibited by 100 micrograms/ml. Piperacillin at 25 micrograms/ml, inhibited 83% of Citrobacter, 58% of Klebsiella, 88% of Enterobacter, and 50% of indole-positive Proteus, Acinetobacter, and Providencia. At 25 micrograms/ml, piperacillin inhibited 95% of Pseudomonas aeruginosa and 78% of Bacteroides fragilis. The minimal inhibitory concentration of piperacillin against Pseudomonas was affected by increasing the inoculum size and by pH. Minimum bactericidal concentrations against Pseudomonas and Serratia often were eightfold greater than the minimum inhibitory concentrations. Piperacillin was equal in activity to ampicillin against enterococci. It was more active than carbenicillin against E. coli, Klebsiella, Enterobacter, and Bacteroides. It was the most active penicillin against Pseudomonas and inhibited many strains of Pseudomonas for which the MICs of carbenicillin were above 200 micrograms/ml. Piperacillin was hydrolyzed by many different beta-lactamases. Synergistic activity of piperacillin was demonstrated when it was combined with amikacin, gentamicin, and cefazolin against P. aeruginosa and members of the Enterobacteriaceae. No antagonism was observed when piperacillin was combined with aminoglycosides; however, antagonism was observed rarely against E. coli when piperacillin was combined with cefazolin.

Chemical Phenomena↗

Comparative in vitro appraisal of piperacillin, including its activity against Salmonella typhi.

Piperacillin was evaluated in vitro against 711 clinical isolates of aerobic and anerobic gram-positive and gram-negative bacteria, including 76 isolates of Salmonella typhi. Piperacillin minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were compared with those of a range of beta-lactam, aminoglycoside, and other antimicrobial agents, and inoculum size effects were considered. The relationship between dilution and disk diffusion tests was studied by regression analysis. In addition, piperacillin was assessed in combination with aminoglycoside and other beta-lactam drugs. This investigation has confirmed the activity of piperacillin against a broad range of bacteria, including Pseudomonas, Enterobacteriaceae, Neisseria, beta-lactamase-negative Haemophilus influenzae, and Staphylococcus aureus as well as enterococci, Bacteroides fragilis, and other anaerobes. All strains of Pseudomonas aeruginosa were inhibited by </=32 mug/ml or less, demonstrating again the potential usefulness of piperacillin in the treatment of pseudomonal infections. S. typhi proved susceptible to piperacillin, all isolates being inhibited by 1 mug/ml. Inoculum size experiments showed that inocula of 10(8) CFU resulted in MICs and MBCs appreciably higher than those resulting from inocula of 10(6) CFU, and inocula of 10(2) CFU resulted in MICs and MBCs appreciably lower than those resulting from inocula of 10(4) CFU. Piperacillin was active against all gentamicin-resistant pseudomonads tested, but not against gentamicin-resistant klebsiellas and enterobacters. Combinations of piperacillin with tobramycin and amikacin were consistently synergistic against Pseudomonas and Serratia isolates. Less consistent results were shown when piperacillin was combined with aminoglycosides or cephalothin against Klebsiella and indole-positive Proteus isolates, although synergy was observed in most cases. Occasional antagonistic reactions were encountered with piperacillin-cephalothin or piperacillin-tobramycin combinations against the latter isolates.

Anti-Bacterial Agents↗

Piperacillin, tazobactam, and gentamicin alone or combined in an endocarditis model of infection by a TEM-3-producing strain of Klebsiella pneumoniae or its susceptible variant.

The efficacy of tazobactam, a beta-lactamase inhibitor, in combination with piperacillin, was studied in vitro and in rabbit experimental endocarditis due to a Klebsiella pneumoniae strain (KpR) producing an extended-spectrum beta-lactamase, TEM-3, or its nonproducing variant (KpS). In vitro, piperacillin was active against KpS (MIC = 4 micrograms/ml, MBC = 8 micrograms/ml with 10(7)-CFU/ml inoculum) but not against KpR (MIC = MBC = 256 micrograms/ml). Tazobactam (1 microgram/ml) restored the activity of piperacillin against KpR (MIC = 2 micrograms/ml, MBC = 4 micrograms/ml). Gentamicin was active against both strains (MIC = 0.25 and 0.5 micrograms/ml for KpS and KpR, respectively). The piperacillin-tazobactam-gentamicin combination was synergistic in vitro. The piperacillin/tazobactam ratio in plasma and in vegetations was always lower than the 4/1 injected dose ratio. In vivo, piperacillin (300 mg/kg of body weight four times a day [QID]) was active against KpS but not against KpR. Tazobactam (75 mg/kg QID) was able to restore the in vivo effect of piperacillin (300 mg/kg QID) against KpR (-3.0 log10 CFU/g of vegetation versus that of controls). Gentamicin (4 mg/kg twice a day [BID]) was active against both strains. Compared with controls, the combination of gentamicin plus piperacillin against KpS (-5.6 log10 CFU/g of vegetation), and the gentamicin-piperacillin-tazobactam combination against KpR (-4.4 log10 CFU/g of vegetation) achieved the greatest decrease in bacterial counts in vegetations and were the only regimens that significantly increased the proportion of sterile vegetations. It is concluded that (i) tazobactam was able to restore the effect of piperacillin against a TEM-3 extended-spectrum Beta-lactamase-producing strain of K. pneumoniae, both in vitro and in a severe experimental infection with high inoculum, when used in a 4/1 piperacillin/tazobactam dose ratio; (ii) gentamicin alone was effective because of the high peak/MBC ratio in plasma; (iii) piperacillin-tazobactam-gentamicin, probably because of the effect of gentamicin in reducing bacterial inoculum in vivo, as stressed by the results obtained by piperacillin-gentamicin against KpS, may be the most effective regimen against KpR.

Animals↗

Timentin versus piperacillin in the therapy of serious urinary tract infections.

In a comparative study, 47 patients received Timentin, a combination of ticarcillin plus clavulanic acid, or piperacillin to treat serious urinary tract infections. Thirty-nine infections in 38 patients were clinically evaluable (21 in the Timentin-treated group and 18 in the piperacillin-treated group). These included pyelonephritis (10 in the Timentin-treated group and five in the piperacillin-treated group), bladder infections with sepsis (11 in the Timentin-treated group and 11 in the piperacillin-treated group) and bladder infections without fever (two in the piperacillin-treated group). The addition of clavulanic acid to ticarcillin greatly enhanced the susceptibility of five of the 28 evaluable pathogens in the Timentin-treated group (two Escherichia coli isolates, two Staphylococcus aureus isolates, and one Klebsiella pneumoniae isolate). The minimal inhibitory concentrations at which 50 and 90 percent of the bacterial growth was inhibited were 4 and 64 micrograms/ml, respectively, for Timentin, and 4 and 32 micrograms/ml, respectively, for piperacillin. All evaluable patients had a satisfactory symptomatic response at the end of the trial. Of 28 evaluable pathogens treated with Timentin, 18 were eradicated up through the one-week post-therapy evaluation period; of 27 evaluable pathogens treated with piperacillin, 18 were eradicated up through the same time period. Eradicated pathogens included E. coli (six of 13 in the Timentin-treated group and six of 11 in the piperacillin-treated group), other Enterobacteriaceae (three of three in the Timentin-treated group and eight of 10 in the piperacillin-treated group), Pseudomonas aeruginosa (two of four in the piperacillin-treated group), enterococcus (two of three in the Timentin-treated group and two of two in the piperacillin-treated group), staphylococcal species (four of five in the Timentin-treated group), and other organisms (three of four in the Timentin-treated group). Resistance did not develop in any of the persisting pathogens. Adverse effects thought possibly to be related to the study drugs were minimal and included rash in one Timentin-treated patient and diarrhea in another.

Adult↗

Detection of galactomannan antigenemia in patients receiving piperacillin-tazobactam and correlations between in vitro, in vivo, and clinical properties of the drug-antigen interaction.

Recent case reports describe patients receiving piperacillin-tazobactam who were found to have circulating galactomannan detected by the double sandwich enzyme-linked immunosorbent assay (ELISA) system, leading to the false presumption of invasive aspergillosis. Since this property of piperacillin-tazobactam and galactomannan ELISA is not well understood, we investigated the in vitro, in vivo, and clinical properties of this interaction. Among the 12 reconstituted antibiotics representing four classes of antibacterial compounds that are commonly used in immunocompromised patients, piperacillin-tazobactam expressed a distinctively high level of galactomannan antigen in vitro (P = 0.001). After intravenous infusion of piperacillin-tazobactam into rabbits, the serum galactomannan index (GMI) in vivo changed significantly (P = 0.0007) from a preinfusion mean baseline value of 0.27 to a mean GMI of 0.83 by 30 min to slowly decline to a mean GMI of 0.44 24 h later. Repeated administration of piperacillin-tazobactam over 7 days resulted in accumulation of circulating galactomannan to a mean peak GMI of 1.31 and a nadir of 0.53. Further studies revealed that the antigen reached a steady state by the third day of administration of piperacillin-tazobactam. Twenty-six hospitalized patients with no evidence of invasive aspergillosis who were receiving antibiotics and ten healthy blood bank donors were studied for expression of circulating galactomannan. Patients (n = 13) receiving piperacillin-tazobactam had significantly greater mean serum GMI values (0.74 +/- 0.14) compared to patients (n = 13) receiving other antibiotics (0.14 +/- 0.08) and compared to healthy blood bank donors (0.14 +/- 0.06) (P < 0.001). Five (38.5%) of thirteen patients receiving piperacillin-tazobactam had serum GMI values > 0.5 compared to none of thirteen subjects receiving other antibiotics (P = 0.039) and to none of ten healthy blood bank donors (P = 0.046). These data demonstrate that among antibiotics that are commonly used in immunocompromised patients, only piperacillin-tazobactam contains significant amounts of galactomannan antigen in vitro, that in animals receiving piperacillin-tazobactam circulating galactomannan antigen accumulates in vivo to significantly increased and sustained levels, and that some but not all patients receiving this antibiotic will demonstrate circulating galactomannan above the threshold considered positive for invasive aspergillosis by the recently licensed double sandwich ELISA.

Animals↗

Two cases of immune haemolytic anaemia, associated with anti-piperacillin, detected by the 'immune complex' method.

BACKGROUND AND OBJECTIVES: Sera containing antibodies to penicillin and penicillin-related drugs are typically thought to react with drug-coated red blood cells (RBCs) (drug adsorption method), but not when the sera are added to drug and RBCs in the same tube ('immune complex' method). Two cases of immune haemolytic anaemia caused by anti-piperacillin have been previously described. Serological details were given in only one patient. In that subject, the antibody was immunoglobulin (Ig)M + IgG and reacted by both the drug adsorption and 'immune complex' methods. MATERIALS AND METHODS: Two patients with cystic fibrosis developed positive direct antiglobulin tests (DATs) and haemolytic anaemia after 11-12 days of piperacillin therapy. Serological studies were performed with piperacillin, Zosyn (piperacillin + tazobactam) and penicillin by using the drug adsorption and 'immune complex' methods. RESULTS: The first patient's serum contained an IgG, complement-activating anti-piperacillin that reacted by the 'immune complex' method only. The second patient's IgM + IgG, complement-activating anti-piperacillin reacted by the 'immune complex' method and agglutinated piperacillin-treated RBCs. An eluate from the patient's RBCs reacted weakly with all RBCs tested without the presence of drug. This patient had evidence of intravascular haemolysis and died. CONCLUSIONS: We describe the third and fourth examples of immune haemolytic anaemia caused by anti-piperacillin; one was associated with fatal haemolytic anaemia. As piperacillin is commonly used in the treatment of cystic fibrosis, anti-piperacillin should be considered whenever patients with cystic fibrosis develop haemolytic anaemia and/or positive DATs.

Adult↗

Comparative in vitro and in vivo activities of piperacillin combined with the beta-lactamase inhibitors tazobactam, clavulanic acid, and sulbactam.

Tazobactam (YTR-830H), a novel beta-lactamase inhibitor, was compared with clavulanic acid and sulbactam for enhancement of the activity of piperacillin against beta-lactamase-producing, piperacillin-resistant clinical isolates. Piperacillin MICs were determined in media containing a fixed concentration of 2 or 4 micrograms of the inhibitors per ml. The higher concentration was generally more effective. Tazobactam was superior to sulbactam in enhancing the spectrum and potency of piperacillin. Although the calvulanic acid combination was more potent, tazobactam was effective for a similar spectrum of resistant gram-negative clinical isolates containing beta-lactamase. MICs were reduced to the susceptible range for Escherichia coli, Klebsiella pneumoniae, Proteus spp., Salmonella spp., and Shigella spp. Combinations with tazobactam and sulbactam, but not clavulanic acid, were effective against Morganella spp. Some antagonism of the activity of piperacillin was observed with clavulanic acid but not with tazobactam or sulbactam. The inhibitors were similarly effective with piperacillin against beta-lactamase-positive Staphylococcus spp. and the Bacteroides fragilis group. Piperacillin-tazobactam was more effective against a broader spectrum of gram-negative enteric bacteria than ticarcillin plus clavulanic acid was. Combinations with tazobactam or clavulanic acid had a broader spectrum of activity than combinations with sulbactam against bacteria that produce characterized plasmid-mediated enzymes of clinical significance. In particular, piperacillin with tazobactam or clavulanic acid, but not with sulbactam, inhibited TEM-1, TEM-2, and SHV-1 enzymes. In vitro activity was reflected in vivo. Tazobactam and clavulanic acid were superior to sulbactam in enhancing the therapeutic efficacy of piperacillin in mice infected with beta-lactamase-positive E. coli, K. pneumoniae, Proteus mirabilis, and Staphylococcus aureus. Only combinations with tazobactam and sulbactam were effective against the Morganella infection. Tazobactam has a good potential for enhancing the clinical efficacy of piperacillin.

Animals↗

Comparative antimicrobial activity of piperacillin-tazobactam tested against more than 5000 recent clinical isolates from five medical centers. A reevaluation after five years.

Piperacillin combined with tazobactam at a fixed concentration (4 micrograms/ml) and a ratio (8:1) was tested against 5,029 aerobic isolates and 447 fastidious organisms, including anaerobes. Among the Enterobacteriaceae, > 95% inhibition was shared only by imipenem (99.1% at < or = 4 micrograms/ml), and some newer cephalosporins (95.1% - 99.8% at < or = 8 micrograms/ml), and piperacillin-tazobactam (95.8% at < or = 16/4 micrograms/ml). Piperacillin-tazobactam was the most active agent tested against nonenteric Gram-negative bacilli (93.5% at < or = 8 micrograms/ml). Ampicillin-sulbactam was the most active agent against staphylococci (95.0% at < or = 8 micrograms/ml), followed by imipenem (91.8%), piperacillin-tazobactam (89.3% at < or = 8/4 micrograms/ml), and cefepime (86.2% at < or = 8 micrograms/ml). Against the enterococci, only ampicillin (93.0% at < or = 8 micrograms/ml) with or without sulbactam, piperacillin (91.0% at < or = 16 micrograms/ml) with or without tazobactam, and imipenem (91.0%) had acceptable activity. Piperacillin-tazobactam and imipenem were the most active drugs tested against all aerobic isolates, inhibiting 93.5% of isolates each. Piperacillin-tazobactam inhibited all fastidious isolates tested, including Haemophilus influenzae (MIC90, 0.094/4 micrograms/ml), Moraxella catarrhalis (MIC90, 0.064/4 micrograms/ml), Neisseira gonorrhoeae (MIC90, < or = 0.016/4 micrograms/ml), and Streptococcus pneumoniae (all MICs, < or = 4/4 micrograms/ml). Against the anaerobic isolates, the most broad-spectrum antimicrobial agents tested were imipenem (100.0%), piperacillin-tazobactam (99.5% at < or = 32/4 micrograms/ml), metronidazole (98.4% at < or = 8 micrograms/ml), and ticarcillin-clavulanic acid (95.1% at < or = 32/2 micrograms/ml). These results are nearly identical to a previous study involving the same five medical centers in 1989. Piperacillin-tazobactam appears to remain a highly effective beta-lactamase inhibitor combination with a wide empiric spectrum and potency in teaching hospitals.

Bacteria↗

Piperacillin sodium: antibacterial spectrum, pharmacokinetics, clinical efficacy, and adverse reactions.

Piperacillin sodium is a beta lactam antibiotic with a broad range of antibacterial activity that includes gram-negative bacilli, gram-positive cocci (except penicillinase-producing S. aureus) and anaerobic pathogens such as Clostridium difficile, and Bacteroides fragilis. Piperacillin inhibits many of the members of the Enterobacteriaceae, including Klebsiella sp and Pseudomonas, at lower concentrations than required for carbenicillin and ticarcillin. Piperacillin sodium is administered by intramuscular and intravenous injection and is widely distributed throughout body fluids and tissues. Like other newer penicillins, piperacillin is excreted by both renal and biliary mechanisms. The primary route of elimination is by glomerular filtration, which results in high urinary concentrations of the unchanged compound. Piperacillin has been approved for patients with serious infection caused by susceptible strains of specific organisms in intra-abdominal, urinary tract, gynecologic, lower respiratory tract, skin and skin structure, bone and joint, and gonococcal infections and septicemia. As with other penicillins, piperacillin has a low frequency of toxicity. The usual dose of piperacillin in adults with serious infections with normal renal function is 3-4 g every 4-6 hr as a 20-30 min infusion, with a maximum dose of 24 g per day. It is stable in most large volume parenteral solutions. Less serious infectins (requiring smaller dosages) may be treated by intramuscular injection; however, no more than 2 g should be given at any one injection site. Overall, piperacillin has a greater degree of activity than other penicillins. Evidence from prospective studies indicates that piperacillin is a highly effective agent for the treatment of patients with infections caused by susceptible organisms.

Bacteria↗

Therapeutic evaluation of piperacillin for acute pulmonary exacerbations in cystic fibrosis.

The efficacy and pharmacokinetics of piperacillin monotherapy were studied in 46 patients with cystic fibrosis. Two patients were dropped from the study within 24 hr of enrollment because of drug-associated nausea and vomiting. Initially fourteen older patients (greater than 12 years) receiving piperacillin 450 mg/kg/day underwent a preliminary evaluation. Based on the results, 30 younger patients (less than or equal to 12 years) randomized in a double-blind fashion received either 600 or 900 mg/kg/day of piperacillin in six divided doses. Pharmacokinetic parameter estimates for t1/2 Vdss, and Cl were similar for first dose and steady-state evaluations. In 27 patients, approximately 43% of the administered dose was recovered in the urine after 4 hr. Piperacillin CiR averaged 49% of the total Cl. No difference in overall clinical efficacy could be identified between 600 and 900 mg/kg/day of piperacillin using two different objective scoring systems. Although a reduction in sputum Pseudomonas colony counts was greater following the 900 mg/kg/day regimen, this appeared to be independent of clinical effect. In 14 patients (32%), a distinct adverse serum-sicknesslike reaction was observed. The incidence of this reaction appeared to increase as the dose of piperacillin increased. All signs and symptoms of this reaction resolved within 36 hr of discontinuing piperacillin administration but recurred immediately on rechallenge in four patients. All patients with the adverse reaction were subsequently treated with beta-lactam antibodies without ill effect. Overall, clinical improvement appeared to be independent of the piperacillin dose. Our data support the use of total daily piperacillin dosages not exceeding 600 mg/kg.

Adolescent↗

Different mechanisms of TEM-1 and Oxa-1 mediated resistance to piperacillin in E. coli.

Clinical isolates of Oxa-1 and TEM-1 producing strains of E. coli were studied. Susceptibility to piperacillin was determined by the agar and broth dilution procedure, and beta-lactam hydrolysis rates measured by the iodometric method. The beta-lactamases were identified by isoelectric focusing. Our data on TEM-1 producing strains showed a statistically significant correlation between the MIC, if determined by the agar dilution test, and the specific beta-lactamase activity. The majority of Oxa-1 producing E. coli was resistant to piperacillin although the inactivation rate of piperacillin was usually low. Cell wall permeability of TEM-1 producing strains of E. coli to piperacillin was below the lower limit of detectability, but preincubation of the E. coli strains in piperacillin containing broth led to increased cell wall permeability. Bactericidal kinetics of an Oxa-1 and TEM-1 E. coli were studied. It revealed that regrowth of the Oxa-1 strain in piperacillin containing broth was associated with a 25% decrease of piperacillin concentrations without the formation of degradation products, suggesting binding of piperacillin to bacterial cells. The TEM-1 plasmid bearing strain inactivated piperacillin, and the degradation products (penicilloate) could be detected.

Bacteriolysis↗

Cefepime plus amikacin versus piperacillin-tazobactam plus amikacin for initial antibiotic therapy in haematology patients with febrile neutropenia: results of an open, randomized, multicentre trial.

BACKGROUND: Standard therapy for suspected infections in patients with profound neutropenia is the combination of a beta-lactam antibiotic plus an aminoglycoside. Cefepime's broad-spectrum activity makes it an option for initial empirical therapy in neutropenic patients. The aim of this study is to evaluate the efficacy and safety of cefepime plus amikacin compared with piperacillin-tazobactam plus amikacin for initial empirical treatment of fever in adult haematology patients with severe neutropenia. METHODS: In this prospective multicentre trial, 969 patients with 984 febrile neutropenic episodes were randomized to receive iv amikacin (20 mg/kg every 24 h) combined with either cefepime (2 g every 8 h) or piperacillin-tazobactam (4 g/500 mg every 6 h). Clinical response was determined at 72 h and at completion of therapy. RESULTS: Eight hundred and sixty-seven episodes were assessable for efficacy (432 cefepime, 435 piperacillin-tazobactam). The frequency of success without modification of the empirical therapy was nearly identical for cefepime plus amikacin (49%) compared with piperacillin-tazobactam plus amikacin (51%). Similar rates of success were found for microbiologically documented infection: 40% versus 39%, respectively. Antibiotic modification was necessary in 49% of cefepime and 44% of piperacillin-tazobactam patients. The overall response rate, with or without modification of the assigned treatment, was 94% in both groups. Drug-related adverse events were reported in 10% of cefepime plus amikacin versus 11% of piperacillin-tazobactam plus amikacin patients. Mortality due to infection occurred in a total of 10 patients (two cefepime, eight piperacillin-tazobactam). CONCLUSION: The empirical regimen of cefepime plus amikacin is equivalent to piperacillin-tazobactam plus amikacin in febrile adult haematology patients with severe neutropenia. KEYWORDS: cefepime, piperacillin-tazobactam, amikacin, empirical antibiotic therapy, febrile neutropenia, haematological malignancy

Adult↗