Teicoplanin (Targocid, Hoechst Marion Roussel): a new glycopeptide antibiotic

The glycopeptides are important antibiotics in the management of Staphylococcal infections. Teicoplanin, the latest member of the group, may offer some advantages over vancomycin, the workhorse drug, which has retained its importance in the presence of increasing major resistance to other antistaphylococcal agents.

Variations of teicoplanin concentrations in neutropenic patients

The aim of this study was to measure the trough plasma concentrations of teicoplanin in neutropenic patients with a view to optimizing the loading dose. Teicoplanin trough plasma concentrations were followed in 11 neutropenic patients after repeated administration of a 6 mg/kg i.v. bolus. The first three injections were given at 12-h intervals, and the rest every 24 h. Trough plasma concentrations at 48 h varied from 5.6 to 13.1 mg/I. The mean trough plasma concentration-time curve indicated a trend towards accumulation. In conclusion, the loading dose of teicoplanin should be tailored to individual neutropenic patients.

Single-dose pharmacokinetics of teicoplanin during hemodialysis therapy using high-flux polysulfone membranes

Teicoplanin is a new glycopeptide antibiotic with potent activity against Gram-positive bacteria. It has been considered to be non-dialyzable due to its high molecular weight (1875-1891 d) and high protein binding (89%). Therefore, a reduced dose was recommended for patients on hemodialysis therapy, with the loading dose being followed by a considerably lower maintenance dose and/or extension of the interval between doses. The present study was performed to evaluate the pharmacokinetics of teicoplanin during hemodialysis therapy using high flux membranes. The pharmacokinetic parameters of teicoplanin were studied in 15 patients with chronic renal failure on hemodialysis. A high flux polysulfone membrane (ultrafiltration coefficient of 40 ml/h/mmHg) was used. Teicoplanin was administered at a dosage of 10 mg.kg-1 body weight in 100 ml isotonic saline solution during the first 10 minutes of hemodialysis therapy. Pharmacokinetic analysis was performed using a three compartment analysis. After a single dose of teicoplanin plasma peak levels were 26.4 +/- 12.0 micrograms/mL (mean +/- SD) after 30 minutes. Teicoplanin concentrations rapidly declined to a nadir of 6.1 +/- 2.5 micrograms/mL at the end of the 3.5-hour session dialysis. Extracorporeal clearance was 39.7 +/- 24.5 mL/min. Removal of 19.3 +/- 7.7% of the drug was estimated if infused during hemodialysis. T 1/2 alpha were 0.37 +/- 0.25 hrs, t 1/2 beta 20.1 +/- 7.1 hrs, and t 1/2 gamma 549.7 +/- 210.5 hrs. We conclude that teicoplanin levels are reduced to a subtherapeutic range during one single high-flux dialysis session if the drug is administered during hemodialysis. Thus, in contrast to previous suggestions relevant amounts of teicoplanin are removed during hemodialysis and thus teicoplanin cannot be viewed as non-dialyzable drug. We recommend obligatory drug monitoring to achieve therapeutic plasma concentrations.

Teicoplanin in cardiac surgery: intraoperative pharmacokinetics and concentrations in cardiac and mediastinal tissues

The concentrations of teicoplanin in the sera and mediastinal and heart tissues of 23 patients undergoing cardiac surgery were measured after two regimens of teicoplanin administration. Intraoperative pharmacokinetic parameters were also obtained. Patients were randomized into two groups. Those in group 1 were given teicoplanin at 6 mg x kg(-1) intravenously at the time of induction of anesthesia. Patients in group 2 were given teicoplanin at 12 mg x kg(-1) during the same period. The maximum concentration in serum (71 +/- 20 and 131 +/- 44 mg x l(-1)), the minimum concentration in serum (3.6 +/- 1.3 and 6.8 +/- 2.1 mg x l(-1)), the area under the concentration-time curve (AUC) from 0 to 12 h (108 +/- 20 and 217 +/- 38 microg x h x ml(-1)), and the AUC from 0 h to infinity (154 +/- 36 and 292 +/- 77 microg x h x ml(-1)) were twice as high after 12-mg x kg(-1) injections as after 6-mg x kg(-1) injections. No differences in mean residence time (9.7 +/- 4.9 and 8.4 +/- 2.7 h) or terminal half-life (8.5 +/- 3.8 and 7.5 +/- 2.3 h) were observed. Teicoplanin penetrated mediastinal and heart tissues but not sternal bone, where the antibiotic was detectable in only 1 of 13 patients in group 1 and 2 of 10 patients in group 2. In group 1, 7 of 13 patients had teicoplanin concentrations in tissue that were lower than the MIC for 90% of the strains of potential pathogens tested (MIC90) that cause infection after cardiac surgery. All of the patients in group 2 but one had teicoplanin concentrations in tissue (other than in sternal bone) far in excess of the MIC90 for the potential pathogens. In conclusion, the 12-mg x kg(-1) regimen of teicoplanin is followed by a significant increase in teicoplanin concentrations in heart and mediastinal tissues and should be preferred to the 6-mg x kg(-1) regimen if teicoplanin is selected for antimicrobial prophylaxis in open heart surgery.

Teicoplanin versus flucloxacillin in the treatment of infection following burns

Antibiotic treatment of patients developing infection after burns is principally based on experience with other surgical patients. Few comparative trials have been performed in burns patients despite the altered pharmacokinetics of antibiotics and the high incidence of Gram-positive infection in the first week. A randomized trial was performed to compare the cure rates of presumed Gram-positive infection in burns patients given teicoplanin (6 mg/kg every 12 h for three doses then daily) or flucloxacillin (1 g every 6 h i.v./p.o.). Both groups received gentamicin if additional Gram-negative infection was thought likely. A total of 64 patients were entered into the study representing 65 episodes of treatment of which 55 were completed. Clinical success was achieved in 22 (73%) of 30 evaluable patients given teicoplanin and in 21 (68%) of 31 evaluable patients given flucloxacillin (not significant). Of 51 patients assessable for bacteriological efficacy, clearance was achieved in 15 (63%) of 24 patients given teicoplanin and in 15 (56%) of 27 patients given flucloxacillin (not significant). Serum trough concentrations of teicoplanin were 9 mg/L in five patients at the steady state. Adverse events were recorded in 15 (48%) of episodes in the teicoplanin group and in 14 (41%) of episodes in the flucloxacillin group. Teicoplanin demonstrated similar efficacy and safety to flucloxacillin with or without gentamicin.

[Discitis in childhood: integrated neuroradiological imaging in diagnosis and follow-up study of one case]

Discitis is an inflammatory disease of the intervertebral disc which has usually a benign evolution in childhood. It often recognizes an infectious etiology. Still discussed however is the possibility of a primitive discal involvement (not secondary to a vertebral inflammation) or of a non infectious etiology and the subsequent more correct diagnostic-therapeutic procedures. We report a case of a girl with discitis diagnosed early and treated with antibiotics and orthopedic corset, whose follow-up shows a benign evolution. We underline the importance of modern neuroradiological imaging: in particular, MR plays a major role in the inflammatory diseases of the column, both in diagnosis and in follow-up. MR scans of the involved disc allow frequent controls without radiogenic risks and with a good resolution because of the multiplanarity typical of the method.

Population pharmacokinetics/pharmacodynamics and individualized drug therapy

Drug concentration and effect vary among patients for any given dose. A goal of population pharmacokinetics (PK) and pharmacodynamics (PD) is to identify patient-specific factors such as weight, creatinine clearance, and age, and associate them with the observed PK/PD differences. Once associated with differences in concentration or response, these distinguishing factors may then be used to better individualize drug therapy. Studies of the population PK of teicoplanin and the population PK and PD of felodipine are summarized as examples of this approach.

Bolus or infusion teicoplanin for intravascular catheter associated infections in immunocompromised patients?

An unexpected low efficacy of teicoplanin in the treatment of coagulase negative staphylococcal (CNS) infections on a regional Bone Marrow Transplant (BMT) Unit led to a retrospective study. CNS infections treated with gylcopeptides in BMT patients with in-dwelling central venous lines between May 1990 and May 1995 were reviewed. Efficacy rates of 50% for teicoplanin compared with 80% for vancomycin despite comparable antibiotic susceptibility. Glycopeptides have bactericidal action which is time dependent. Teicoplanin was administered by bolus injection during the study period and it is suggested that this observed difference in efficacy is caused by the short duration of exposure of luminal bacteria.

Treatment of endocarditis with teicoplanin: a retrospective analysis of 104 cases

Infective endocarditis is an uncommon disease but retains a high mortality. Glycopeptides are used for patients with resistant pathogens, those allergic to penicillins or for those outside the hospital. The once daily administration of teicoplanin and its low toxicity suggest that it would be suitable for use in the long courses required for endocarditis. However, the dosage and combinations to be used require further study. A retrospective review has been made of 104 episodes of endocarditis treated with teicoplanin in 101 patients seen over 7 years. Most patients had been referred to major London hospitals following failure of medical treatment. After three loading doses of 400 mg, teicoplanin was given at a dose of 400 mg/day in combination with other antibiotics such as gentamicin. Follow up was for one year. The most common pathogens were Streptococcus sanguis (15 cases), Staphylococcus aureus (13 cases) and Staphylococcus epidermidis (10 cases). Of 80 patients febrile at the start of treatment with teicoplanin, 63 (79%) lost their fever within a median of 2 days (1-35 days). Cure without surgery was effected in 50 (48%) and 75% of patients survived. Other antibiotics, usually gentamicin or rifampicin, were used in 92 (90%) of patients. Two strains of Streptococcus spp. were said to be resistant but there was no relationship between MIC of teicoplanin and outcome. Pathogens with a high MBC tended to be more likely to resist treatment. Adverse effects resulted in the withdrawal of teicoplanin in 20 cases (19%) but most events were mild and renal deterioration occurred in only five patients. Teicoplanin was effective in the treatment of endocarditis and appeared to be safe given the severity of disease in the patients treated.

[Imipenem combined with teicoplanin or vancomycin in the initial empirical treatment of febrile neutropenia. Analysis of the primary response and of a global sequential strategy in 126 episodes]

The results of empiric antibiotic therapy in 126 episodes of febrile neutropenia in patients with hematologic neoplasms postchemotherapy and bone marrow transplantation are presented. The main objective of this work was the study of the initial control of infection comparing two glycopeptidic antibiotics: vancomycin and teicoplanin combined with imipenem in first line of empiric therapy. The secondary objective was to analyze the overall control of infection during the complete episode of neutropenia using a sequential empiric antibiotic therapy course which included the addition of amikacin followed by intravenous amphotericin B when fever persisted or recurred without microbiological documentation. Both initial courses (no guidelines), imipenem + vancomycin (arm A) and imipenem + teicoplanin (arm B) resulted in a similar percentage of response at 72 hours, both in episodes of fever of unknown origin (FUO) (55% and 68%, respectively; p = NS) and in those microbiologically documented (54% and 34.5%, p = NS); 58% and 79% of these episodes, respectively, were caused by gram-positive organisms. About 60% of patients in both arm ultimately required the empiric addition of amikacin, with or without amphotericin B, because of persistence or recurrence of fever; the percentage of overall responses in both arm did not differ significantly, both in FUO (70% and 86%, p = NS) and in microbiologically documented episodes (71% and 45%, p = NS). The overall infectious mortality for the whole group was 1.58%. In conclusion, no significant differences were observed in the clinical response or in toxicity between the combination of imipenem with any of the two glycopeptides: vancomycin or teicoplanin, for the initial empiric therapy of febrile neutropenia. The sequential empiric use of amikacin followed by amphotericin B assured an adequate overall control of infection in a group of patients with prolonged severe neutropenia.

Teicoplanin pharmacokinetics in pediatric patients

BACKGROUND

The incidence of methicillin-resistant Gram-positive bacteria infections in febrile neutropenic children is high. Teicoplanin is an alternative treatment to vancomycin in these patients but few pharmacokinetic studies of teicoplanin in children have been conducted and optimal dosages have not been well-established.

OBJECTIVES

To assess the pharmacokinetics of teicoplanin in combination with another antibiotic in Gram-positive infections in pediatric patients undergoing bone marrow transplantation and to determine the most appropriate dosage regimen for this type of patient.

METHODS

We studied 21 patients divided into 2 groups. In Group A (n = 9) the dosage regimen consisted of 3 loading doses of 10 mg/kg at 12-h intervals, followed by a maintenance dosage of 10 mg/kg/day. Group B (n = 12) received the same loading dose and a maintenance dosage of 20 mg/kg/day. Plasma teicoplanin concentrations were monitored in all patients from the second day after the start of treatment and periodically thereafter. Serum concentrations above 10 mg/l were established as desirable trough values.

RESULTS

In Group A trough values > 10 mg/l were not reached in five patients and treatment was modified owing to persistent fever. In Group B all patients attained trough values > 10 mg/l. Tolerance to treatment was excellent.

CONCLUSION

In febrile neutropenic pediatric patients undergoing bone marrow transplantation, maintenance dosages of teicoplanin between 15 and 20 mg/kg/day assure serum concentrations above 10 mg/l. Dosages of 10 mg/kg/day do not assure serum through values above 10 mg/l.

Influence of oral glycopeptides on the fecal flora of human volunteers: selection of highly glycopeptide-resistant enterococci

Changes in fecal flora were evaluated in 22 healthy volunteers administered oral vancomycin or teicoplanin in 1989-1991 in Belgium. Evaluation of 5 colonies per subject revealed no glycopeptide-resistant enterococci in the predominant flora before glycopeptide administration; however, large numbers (mostly Enterococcus faecium) emerged by the end of the study in 14 (64%) of the subjects. Pediococci and lactobacilli also increased in number. In 1992, 40 healthy volunteers and 33 cancer patients were evaluated by plating stool samples directly onto selective media containing vancomycin; low numbers of vancomycin-resistant enterococci (< 50 cfu/g) were found in 11 (28%) of the 40 and 4 (12%) of the 33 samples, respectively. DNA restriction fragment length polymorphism analysis showed that most isolates were different, but all contained vanA in Tn1546-like elements. These results indicate that vanA and Tn1546-like elements were common in Belgium as early as 1989 and that community-based individuals in that location likely form a major reservoir for glycopeptide-resistant enterococci.

Comparison of vancomycin, teicoplanin, metronidazole, and fusidic acid for the treatment of Clostridium difficile-associated diarrhea

We conducted a prospective, randomized study to compare the efficacy of oral fusidic acid, oral metronidazole, oral vancomycin, and oral teicoplanin for the treatment of Clostridium difficile-associated diarrhea. Treatment resulted in clinical cure for 94% of the patients who were treated with vancomycin, 96% of those treated with teicoplanin, 93% of those treated with fusidic acid, and 94% of those treated with metronidazole. Clinical symptoms recurred in 16% of patients treated with vancomycin, 7% of those treated with teicoplanin, 28% of those treated with fusidic acid, and 16% of those treated with metronidazole. There was asymptomatic carriage of C. difficile toxin in 13% of patients treated with vancomycin, 4% of those treated with teicoplanin, 24% of those treated with fusidic acid, and 16% of those treated with metronidazole. No adverse effects related to therapy with vancomycin or teicoplanin were observed. Considering the costs of treatment, our findings suggest that metronidazole is the drug of choice for C. difficile-associated diarrhea and that glycopeptides should be reserved for patients who cannot tolerate metronidazole or who do not respond to treatment with this drug.

Population pharmacokinetic study of teicoplanin in severely neutropenic patients

The teicoplanin pharmacokinetics (PK) of 30 febrile and severely neutropenic patients (polymorphonuclear count, < 500/mm3) with hematologic malignancies were compared with those determined for five healthy volunteers (HV). Neutropenic patients were given piperacillin combined with amikacin, and teicoplanin was added to the regimen the day fever developed in patients suspected of having a staphylococcal infection or 48 h later. Teicoplanin was given intravenously at a dosage of 6 mg/kg of body weight at 0, 12, and 24 h and once a day thereafter. Five to eleven blood samples per patient were collected. Teicoplanin concentrations were measured by liquid chromatography. A bicompartmental model was fitted to the data by a nonlinear mixed-effect-model approach. Multiple-linear regression analysis was applied in an attempt to correlate PK parameters to nine covariates. The mean trough concentrations of teicoplanin 48 h after the onset of treatment and 24 h after the last injection (last trough) +/- standard deviations were 8.8 +/- 4.1 and 17.5 +/- 13.5 mg/liter, respectively. A significant increase was noted in the mean rate of elimination clearance of teicoplanin in neutropenic patients compared with that of HV (0.86 versus 0.73 liter/h, P = 0.002), as was the case with rates of distribution clearance (5.89 versus 4.94 liter/h, P = 0.002); the mean half-life of distribution was significantly shorter in patients than in HV (0.43 versus 0.61 h, P = 0.002). In contrast, the volumes of the central compartment (ca. 5.8 liters for both groups), the volumes of distribution at steady state (HV, 37.6 liters; patients, 55.9 liters), and the elimination half-lives (HV, 39.6 h; patients, 52.7 h) were not significantly different between HV and neutropenic patients. Interindividual variabilities of rates of clearance (coefficient of variation [CV], 43%) and elimination half-lives (CV, 56%) were mainly explained by the variabilities among rates of creatinine clearance. Interindividual variabilities of the volumes of the central compartment (CV, 33%) and the volumes of distribution at steady state (CV = 51%) were correlated to interindividual variabilities among numbers of leukocytes and the ages of patients, respectively. On the basis of the population PK model of teicoplanin, simulations were made to optimize the dosing schedule. A supplemental 6 mg/kg dose of teicoplanin at 36 h resulted in a trough concentration at 48 h of 16.0 +/- 4.5 mg/liter, with only 7% of patients having a trough concentration of less than 10 mg/liter, compared with 46% of patients on the usual schedule.

[Adequate intrathecal diffusion of teicoplanin after failure of vancomycin, administered in continuous infusion in three cases of shunt associated meningitis]

Glycopeptides which have excellent in vitro activity against the Gram-positive causal agents of meningitis unfortunately have a poor CSF penetration. Vancomycin distribution into CSF is improved when administered by a continuous intravenous route and staphylococcal shunt related infection have been reported to be cured. Teicoplanin has good in vitro activity against a lot of staphylococci, and activity superior to vancomycin, against streptococci and is less toxic. In three children with shunt ventriculitis (S epidermidis 2, S. faecalis 1) despite a continuous infusion, vancomycin 15 mg/kg over 60 minutes onset, then 50 mg/kg/day was clinically and bacteriologically ineffective with very poor CSF levels even if high blood levels. After failure of vancomycin we used teicoplanin as a continuous i.v. infusion 6 mg/kg over 60 mn onset, then 12 mg/kg/day. This treatment was quickly effective and well tolerated.

Concentration of teicoplanin in the serum of adults with end stage chronic renal failure undergoing treatment for infection

We examined the adequacy of the following schedule for the administration of i.v. teicoplanin to patients with chronic renal failure: three doses of 6 mg/kg at 12 h intervals, a fourth dose 24 h later and then subsequent doses every 72 h. Eight infected patients undergoing dialysis were investigated, with serum antibiotic concentrations measured ten minutes before and one hour after administration. Mean trough concentrations were 6.9 +/- 3.1 mg/L on day two, 9.8 +/- 4.4 mg/L (day three), 9.2 +/- 4.8 mg/L (day six), 10.9 +/- 5.5 mg/L (day nine), 12.1 +/- 6.1 mg/L (day 12) and 14.8 +/- 8.0 mg/L (day 15). The proposed schedule achieved adequate trough serum teicoplanin concentrations by 48 h in six out of eight patients examined. The dosage regimen was well tolerated.

Antibiotic-resistant endocarditis in a hemodialysis patient

A chronic dialysis patient developed persistent bacteremia as a result of infection with Enterococcus faecium. During the patient's illness, resistance to ampicillin, gentamicin, vancomycin, and teicoplanin developed. Despite arteriovenous (AV) graft removal and an extensive but inconclusive search for the source of the infection, bacteremia persisted. On autopsy, the patient was found to have had aortic-valve endocarditis. Endocarditis is a well-known complication in dialysis patients. Multidrug-resistant organisms are becoming more prevalent in hospitalized patients as well. Risk factors for the development of endocarditis in dialysis patients include catheters, AV grafts, and calcific valvular disease, all in conjunction with frequent access to the circulation. Avoidance of temporary catheter use by prompt placement of AV fistulas or grafts and consideration of their early use, the meticulous care of catheters once in place, and treatment of the nasal carriage of Staphylococcus aureus may lower the incidence of bacteremia and therefore endocarditis in dialysis patients. The removal of infected catheters and/or AV grafts if prompt clearing of the blood with antibiotics does not occur is the next step, followed by valve replacement in selected cases. The routine use of vancomycin in the dialysis population should be reevaluated in light of the development of high-level antibiotic-resistant organisms.

Efficacy of femoral intra-arterial administration of teicoplanin in gram-positive diabetic foot infections

In this study the efficacy and safety femoral intra-arterial administration of teicoplanin in the treatment of diabetic foot infections caused by gram-positive bacteria were evaluated. Twenty-five hospitalized diabetic patients with foot ulcers or with foot ulcers and metatarsophalangeal osteomyelitis were included in the study. In the ulcers Staphylococcus aureus was present alone in 16 patients and was associated with Pseudomonas aeruginosa in 2 patients, with Candida albicans in 2, and with coagulase-negative Staphylococcus in 1 patient. In 4 patients other gram-positive bacteria were isolated. All isolated strains were resistant to various antibiotics tested. Teicoplanin, 200 mg, was administered once a day by femoral intra-arterial injection for an average period of 14.72 +/- 7.16 days (range ten to thirty-six days). Six patients were treated with an additional antibiotic intramuscularly or intravenously because of a mixed infection. At the end of the therapy microbiological assessment confirmed that gram-positive infection was eliminated in all patients. Clinical outcome demonstrated that healing occurred in 18 patients (72%) and improvement in 7 patients (28%). No adverse drug reactions were observed during the treatment. The results demonstrate that femoral intra-arterial administration of teicoplanin was highly effective in skin- and bone-infected lesions in the diabetic foot. This method may represent a further advantage in management of this severe diabetic complication.

A Bayesian approach to drug disposition evaluation: application to teicoplanin

We suggest a Bayesian method in order to evaluate the disposition kinetics of the drug plasma concentrations after intravenous (i.v.) and/or after extravascular administration of the drug in the same subject pooled with information obtained taking into account previous pharmacokinetics of the drug. This approach was applied to the investigation of teicoplanin pharmacokinetics after 200 mg i.v. administration to 10 healthy subjects.

Experience with outpatient intravenous teicoplanin therapy for chronic osteomyelitis

Thirty-seven patients with acute exacerbations of chronic osteomyelitis caused by methicillin-susceptible Staphylococcus aureus (n = 13), methicillin-resistant Staphylococcus aureus (n = 12), methicillin-susceptible coagulase-negative staphylococci (n = 9), methicillin-resistant coagulase-negative staphylococci (n = 1) and enterococci (n = 2) were treated intravenously with teicoplanin. After a loading dose of 7 to 16 mg/kg (median 11 mg/kg) for 4 to 7 days, patients received 9 to 25 mg/kg (median 14 mg/kg) on Mondays, Wednesdays and Fridays in an outpatient setting to reach trough serum levels between 5 mg/l and 15 mg/l. The duration of treatment ranged from 28 to 150 days (median 60 days). Cure was obtained in 14 (38%) and improvement in 17 (46%) cases, and failure was observed in 6 (16%) patients. Adverse effects occurred in 6 patients, and caused discontinuation of treatment in 3 patients. The financial savings exceeded US$60,000 per patient compared with the high hospitalization costs of inpatient treatment.

Influence of arterio-venous haemofiltration on teicoplanin elimination

The pharmacokinetics of teicoplanin infused for 30 min at a dose of 6 mg kg-1 was studied in 11 infected patients under continuous arterio-venous haemofiltration (CAVH). Serum teicoplanin levels were assayed by h.p.l.c. over 24 h. After 0.5 h, i.e. at the end of the infusion, the mean plasma concentration was 49.6 +/- 15.1 mg l-1. At the last sampling time (24 h), the mean concentration was 2.6 +/- 1.0 mg l-1. The concentration of teicoplanin was determined in the haemofiltrates. The percentage of the administered dose recovered in the haemofiltrate was low: less than 1% for seven patients, between 1.8 and 3.7% for three patients and 7% for one patient. CAVH patients should be given teicoplanin using the same dosage regimens as previously described for patients with renal impairment.

"In-situ" Teicoplanin for central venous catheter infection

Infection of central venous catheters (CVC) is a relatively common occurrence in immunocompromised patients, management of which has included I.V. antibiotics +/- removal of catheter. We have previously demonstrated that intracatheter administration of Amikacin empirically, successfully eradicated all bacterial infections except those due to S. epidermidis. A study was subsequently undertaken to treat gram positive cocci infections of CVC with intracatheter Teicoplanin. Eleven patients attending a single institution with documented gram positive cocci infection of CVC over a one year period were included in the study. Teicoplanin was instilled with heparinised saline once daily into the infected lumen of the CVC and allowed to remain for 24 hours. Treatment was continued for 48 hours after negative cultures were reported. Teicoplanin was successful in eradicating infection in 100% of cases. Mean duration of treatment was six days (range 4-9 days). Four patients subsequently developed a further infection, a mean of 13 weeks from first infection, only one of which was due to the same organism and this was successfully treated by a further course of Teicoplanin. No side effects were reported and catheter life was prolonged a mean of 132 days after completion of treatment. The use of Teicoplanin in this way for treatment of gram positive cocci infection of CVC is highly effective; once daily administration of antibiotic enables treatment to be given on an outpatient basis, thereby minimising hospital admission.

Adult polyomyositis/dermatomyositis associated with acute myeloid leukemia. A case report

Reports of PM/DM associated with haematologic disorders are rare. We describe a 62-year-old man suffering from PM/DM who developed acute myeloid leukemia. The possible paraneoplastic nature of PM/DM in this patient is discussed.

Teicoplanin and oral ciprofloxacin as outpatient treatment of infective episodes in patients with indwelling central venous catheters and haematological malignancy

Central venous catheters are often the focus of microbial colonization which may cause bacteraemia (or fungal septicaemia) in both neutropenic and non-neutropenic patients. Such episodes are associated with considerable morbidity and may require admission to hospital or replacement of the central line. We have used the combination of intravenous teicoplanin and oral ciprofloxacin to treat such episodes as outpatients, achieving a salvage rate of 74%. Seven of thirty-five episodes resulted in removal of the line. The treatment was well tolerated and well-suited to the day ward setting.

Teicoplanin pharmacokinetics and dosage recommendations in chronic hemodialysis patients and in patients undergoing continuous veno-venous hemodialysis

Multiple-dose pharmacokinetics of teicoplanin, a glycopeptide antibiotic against gram-positive infections, were studied in 9 chronic hemodialysis (HD) patients and in 7 patients with an acute renal failure (ARF) treated by continuous veno-venous hemodialysis (CVVHD). After a loading dose of 800 mg i.v. the 400 mg maintenance doses were administered according to a target trough concentration of 5-15 mg/l. Using the Bayesian estimation method implemented in the computer program Abbottbase Pharmacokinetic System (PKS), we defined an open three-compartment kinetic model for teicoplanin and calculated the individual pharmacokinetics. The mean terminal elimination half-life was 176 +/- 41.3 h in the HD group and 99 +/- 22.3 h in the CVVHD group (p < 0.005). The total body clearance (CL) was 4 +/- 1.2 ml/min and 9.2 +/- 1.7 ml/min in the HD and CVVHD patients respectively (p < 0.001). The mean reduction of the serum levels during a HD session was 9.1% in the patients dialysed with a F8 filter and 20.2% with a high-flux F60 filter (p < 0.001). The resulting extraction rate was 10 +/- 3.6% (F8) which is similar to the unbound fraction. The elimination of teicoplanin during CVVHD therapy strongly depended on the ultrafiltration rate (UFR) (r = 0.923, p < 0.05). An UFR of 15.6 l/24 h resulted in a removal of 32%/24 h of a 400 mg dose and an UFR of 6.2 l/24 h in 9.5%/24 h respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of cerebrospinal fluid shunt infections with teicoplanin

Intraventricular teicoplanin 10-15 mg was administered daily to three patients with cerebrospinal fluid (CSF) shunt infections due to Staphylococcus epidermidis and Enterococcus faecalis. Teicoplanin concentrations in CSF 24 h after intrathecal injection of the drug exceeded four- to eight-fold the MICs for the infecting microorganisms. CSF cultures rapidly became negative and shunt devices were withdrawn and replaced in the same operative procedure. Intraventricular teicoplanin was well tolerated. No relapses occurred. Teicoplanin may be an alternative to vancomycin for the antimicrobial therapy of CSF shunt infections.

Teicoplanin versus cefamandole in the prevention of infection in total hip replacement

In a prospective, controlled, single-blind study the efficacy of teicoplanin versus cefamandole in preventing infections in total hip replacement was investigated in 496 consecutive patients. A single intravenous dose of teicoplanin (400 mg) was as effective as two intravenous doses of cefamandole (2 g before and 1 g after surgery). No major complications were observed in either group. Infective wound complications were observed only in the cefamandole group. These infections, although not dangerous for the patients, required supplementary antibiotic treatment in all cases. Teicoplanin is a reasonable choice as a prophylactic agent in orthopaedic surgery when a high risk of infection due to staphylococci is present.

Teicoplanin alone or combined with rifampin compared with vancomycin for prophylaxis and treatment of experimental foreign body infection by methicillin-resistant Staphylococcus aureus

The prophylactic and therapeutic activities of teicoplanin were evaluated in two different experimental models of foreign body infections caused by methicillin-resistant Staphylococcus aureus (MRSA). In a guinea pig model of prophylaxis, subcutaneously implanted tissue cages were infected at a > 90% rate by 10(2) CFU of MRSA in control animals. A single dose of 30 mg of teicoplanin per kg of body weight administered intraperitoneally 6 h before bacterial challenge was as effective as vancomycin in preventing experimental infection in tissue cages injected with either 10(2), 10(3), or 10(4) CFU of MRSA. In a rat model evaluating the therapy of chronic tissue cage infection caused by MRSA, the efficacy of a 7-day high-dose (30 mg/kg once daily) regimen of teicoplanin was compared with that of vancomycin (50 mg/kg twice daily). Whereas high levels of teicoplanin were found in tissue cage fluid, continuously exceeding its MBC for MRSA by 8- to 16-fold, no significant reduction in the viable counts of MRSA occurred during therapy. In contrast, either vancomycin alone or a combined regimen of high-dose teicoplanin plus rifampin (25 mg/kg twice daily) could significantly decrease the viable counts in tissue cage fluids. Whereas the bacteria recovered from tissue cage fluids during therapy showed no evidence of teicoplanin resistance, they failed to be killed even by high levels of this antimicrobial agent. The altered susceptibility of in vivo growing bacteria to teicoplanin killing might in part explain the defective activity of this antimicrobial agent when used as monotherapy against chronic S. aureus infections. These data may indicate the need for a combined regimen of teicoplanin with other agents such as rifampin to optimize the therapy of severe staphylococcal infections.

Successful treatment of meningitis due to multiply resistant Enterococcus faecium with a combination of intrathecal teicoplanin and intravenous antimicrobial agents

Following neurosurgery necessitated by intractable seizures, Enterococcus faecium meningitis that was resistant to ampicillin, a high-level aminoglycoside (MIC, > 2,000 micrograms/mL), and vancomycin developed in a 6-year-old boy. Treatment with intrathecal teicoplanin in combination with intravenous clindamycin, rifampin, and ampicillin was successful. The role of intravenous and intrathecal antibiotics in treatment of this infection is discussed. This case is illustrative of the safety and potential usefulness of intrathecally administered teicoplanin.

Once daily antibiotic regimen in paediatric oncology

The feasibility and efficacy of a once daily antibiotic regimen were assessed in children with malignant tumours. Over a 44 month period, 296 febrile episodes were treated with a regimen of once daily ceftriaxone-amikacin (and teicoplanin or vancomycin if the patient had a central line). The treatment was successful in 272 (92%) episodes without modification of the antibiotic regimen, and only one patient died of uncontrolled sepsis. A once daily antibiotic regimen is therefore feasible and worthwhile in the treatment of febrile episodes in children with cancer.

Treatment of experimental endocarditis caused by penicillin-resistant Streptococcus sanguis with different doses of teicoplanin

Streptococcus viridans continues to be the most frequent causal agent of infective endocarditis. Treatment has become more complicated due to the increase in resistance to penicillin and cephalosporins. In order to study the possible efficacy of teicoplanin at low and high doses, this antibiotic was investigated in rabbits as a monotherapy and in association with gentamicin. The effects were compared with a control group and a group given classical penicillin-gentamicin treatment. Infective endocarditis was induced in 120 rabbits with a clinical isolate of Streptococcus sanguis. Treatment was started 48 h after infection, and lasted 5 days. Animals were divided into 6 groups of 20 rabbits each: G1, untreated controls; G2, penicillin+gentamicin; G3 low-dose teicoplanin; G4, low-dose teicoplanin+gentamicin; G5, high-dose teicoplanin; and G6, high-dose teicoplanin+gentamicin. Response to therapy was evaluated with mortality curves, negativization of blood cultures, concentration of S. sanguis in aortic vegetations and rate of sterilization of vegetations. Vegetation weight was significantly lower in treated groups than in controls; lower weights were found in G4, the only treatment that sterilized 65% of vegetations. Death occurred only in the control group (10% mortality). Negativization of blood cultures was greatest and most rapid in G4, followed by G6. Concentrations of S. sanguis in aortic vegetations were significantly lower in all treated groups compared with controls, with the lowest being in groups G4 and G6. Combined treatment with teicoplanin+gentamicin may be highly efficacious in patients with endocarditis caused by penicillin-resistant Streptococcus sanguis. High-dose teicoplanin+gentamicin does not seem to be more efficacious than low-dose teicoplanin+gentamicin.

A prospective, randomized study of pefloxacin versus teicoplanin in the treatment of gram-positive coccal infections in cancer patients: early termination due to emergence of resistance to fluoroquinolones

A randomized prospective study comparing pefloxacin to teicoplanin in the treatment of gram-positive infections in cancer patients was prematurely terminated because of the emergence of pefloxacin resistance associated with oxacillin resistance in Staphylococcus aureus and coagulase-negative staphylococci. Among 56 patients evaluated for efficacy (26 pefloxacin and 30 teicoplanin) and infected with bacteria susceptible to both antibiotics, the clinical cure and eradication rates were similar for pefloxacin (80.5% and 77.3% respectively) and teicoplanin (66.6% and 52.2% respectively). The relapse rates (15% and 10% for pefloxacin and teicoplanin respectively) and the overall mortalities within 1 month (42% and 31%) were similar.

Antiinfective prophylaxis with ceftazidime and teicoplanin in children undergoing high-dose chemotherapy and bone marrow transplantation

Sixty children treated for solid tumors with high-dose chemotherapy followed by bone marrow transplantation were randomly assigned to one of two antibiotic protocols. Group A received prophylaxis consisting of ceftazidime plus teicoplanin beginning before the onset of aplasia and fever; group B received exactly the same antibiotic regimen but beginning at the onset of fever. The two groups were compared in terms of the rate of septicemia, fever of unknown origin, the time-lapse before the appearance of septicemia, the sensitivity of the causative organisms to the antibiotics, the effect of the latter on the intestinal flora, and the rate of fungal infections. The incidence of septicemia was significantly lower in group A (6.6%) than in group B (24.0%), mainly due to the prevention of episodes of early onset. Similarly, the appearance of the first episode of fever was delayed in group A, and the overall duration was reduced. Amphotericin B was prescribed empirically with the same rule in both groups, but three children in group A did not require amphotericin B. The effect on the intestinal flora was similar in the two groups; it must, however, be closely monitored so that the presence of potential pathogens can be dealt with appropriately.

[Teicoplanin in the prevention of wound infections in major ambulatory surgery]

Wound infection is a frequent complication and is related to various parameters: type of surgery, patient's age, nutritional status, associated diseases, length of surgery and hospital stay, use of prosthesis and drainage and finally surgeon's ability. The frequency of wound infection is reported between 1.5%-5.1% after "clean surgery" and the greatest source of microbial contamination is due to GRAM positive cocci either aerobic or anaerobic. The Authors present their experience of ultra short-term prophylaxis with Teicoplanin in 375 patients undergoing major ambulatory surgery. Median age was 49 years (15-87 ys); patients over 65 years were 22%. Hernias of the abdominal wall and varicose veins represent the diseases most commonly operated on. In 30% of the cases the patients selected for major ambulatory surgery were in II and III classes according to the standards of the American Society of Anaesthesiologists (A.S.A.). The ultra short-term prophylaxis with Teicoplanin was administered as follows: 400 mg, i.v., thirty minutes pre-operatively. The operations were performed under local or loco-regional anaesthesia. The choice of Teicoplanin was based on the strong bactericidal activity on GRAM positive cocci, including the methicillin-resistant Staphylococcus aureus infections, and on the long activity of the drug. The results were considered according to the American College of Surgeons scheme: no wound infection was observed and excellent local and general drug's tolerance were noticed. Ultra short-term prophylaxis in ambulatory surgery was chosen for the following reasons: large use of prosthesis, major risk of sepsis in older patients and at last for a badly accepted infective complications in outpatient surgery.

Treatment of Clostridium difficile associated diarrhea and colitis with an oral preparation of teicoplanin; a dose finding study. The Swedish CDAD Study Group

92 patients with antibiotic-associated diarrhea were randomized to receive oral teicoplanin 100 mg twice daily for 7 days (BID group); or 50 mg 4 times daily for 3 days, followed by 100 mg twice daily for 4 days (QID group) in a randomized, double-blind, multicentre study. Clostridium difficile was demonstrated by culture and/or cytotoxin test in 49 (53%) patients, of whom 47 (23 male, 24 females, mean age 65 years; 23 in the BID group, 24 in the QID group) were evaluable for clinical efficacy. Prior treatment with cephalosporins was registered in 49%, isoxazolyl-penicillins in 33% and clindamycin in 20% of the C. difficile positive patients. On the last day of treatment, 96% (23 of 24 patients) in the QID group were found cured, compared with 70% (16 of 23 patients) in the BID group (p = 0.02). On days 2 and 3 of treatment, QID group patients had significantly fewer loose stools per day (p < 0.05) than those of the BID group. Clinical recurrence, within 4 weeks post-treatment, occurred in 35% and 33% of the patients in the BID and QID groups, respectively. The bacteriological elimination rate 4 weeks post-treatment was 55% in the BID group and 59% in the QID group. The study was terminated prematurely due to the unexpectedly high clinical failure and recurrence rate in C. difficile positive patients treated with the BID dosage regimen.

Influence of the pre-treatment duration of infection on the efficacies of various antibiotic regimens in experimental streptococcal endocarditis

The influence of the pre-treatment duration of infection on the efficacies of three different antibiotic regimens was investigated in a rabbit model of subacute endocarditis caused by a novel, nutritionally-variant species, Streptococcus adjacens strain GaDT. Treatment was initiated either 6 or 10 days after bacterial inoculation (days 7 and 11 respectively) and comprised procaine penicillin (150,000 IU/kg bd), alone or combined with tobramycin (12 mg/kg od), teicoplanin (10 mg/kg bd), all administered by the intramuscular route for 4 days. The MICs and MBCs of penicillin, tobramycin and teicoplanin were 0.015 and 1 mg/L, 8 and 16 mg/L and 0.25 and 256 mg/L respectively. In the control rabbits, the mean (+/- S.D.) weights of the vegetations were 25 +/- 16 mg on day 7 and 45 +/- 34 mg on day 11 (P = 0.06). The mean (+/- S.D.) reductions in the number of cfu in the vegetations of the treated groups of animals after completion of therapy which had been started on days 7 and 11, compared with the mean numbers of cfu in the vegetations of the untreated controls on days 7 and 11 (delta log10 cfu/g), were 4.0 +/- 1.3 and 2.1 +/- 1.5 respectively for penicillin (P < 0.05), 3.2 +/- 1.8 and 2.4 +/- 1.8 respectively for teicoplanin and 5.4 +/- 1.2 and 5.2 +/- 1.2 respectively for the combination of penicillin and tobramycin. The increase in the size of the vegetations and changes in the metabolism of the bacteria within the vegetations between days 7 and 11, as demonstrated by electron microscopy, might explain why penicillin was more effective earlier in the course of the disease and why the influence of the duration of infection before treatment was initiated, varied according to the antibiotic regimen. These results suggest that the use of bactericidal regimens, such as the combination of penicillin and tobramycin, which are equally effective in reducing the bacterial counts in vegetations which have been infected for both long and short periods could minimize the risk of relapse in patients with endocarditis in whom there have been long delays before initiating treatment and/or who have large vegetations.

Ceftriaxone alone or in Combination with Teicoplanin in the Management of Febrile Episodes in Neutropenic Children and Adolescents with Cancer on an Outpatient Base

STUDY OBJECTIVE

This study prospectively investigated the outpatient once daily therapy with ceftriaxone alone or if necessary in combination with teicoplanin, in the treatment of infections in children and adolescents with chemotherapy-induced neutropenia or aplastic anemia.

PATIENTS

42 patients 1-22 years of age suffering from solid tumors, hematological and oncological diseases, with clinical signs of infection, increased serum CRP (> 1 mg/dl) and/or fever above 38.5 degrees C and neutropenia (WBC count and/or ANC < 1 x 10(9)/l) were included in this outpatient based study. One important exclusion criterion was poor clinical condition with symptoms of septic shock.

METHODS

After bacterial, fungal and viral cultures had been obtained, single agent broad spectrum cephalosporin treatment was initiated with ceftriaxone applied once daily in a dose of 80 mg/kg body weight as short infusion over 30 min. Daily examinations included WBC, CRP, physical inspection and reassessment. In case of persistence or increase of fever and CRP, either outpatient management was carried on with teicoplanin added or patients were hospitalized and switched to combination antibiotic regimen.

RESULTS

There were 64 febrile episodes in 42 patients. Single agent once daily broad spectrum cephalosporin was adequate in 43/64 (67%) of infectious episodes in neutropenic patients. For persisting or increased fever or CRP elevation, 9 patients were treated with ceftriaxone and teicoplanin successfully. Thus hospitalized was avoided in 52/64 (81%) of infectious episodes.

Studies on drug monitoring in thrice and once daily treatment with aminoglycosides

OBJECTIVES

To investigate at what time the peak level should be determined under conventional thrice daily (t.i.d.) administration of the aminoglycoside netilmicin and to study its serum concentrations under once daily (od) treatment to define the required daily dose and to gain information about convenient drug monitoring.

DESIGN

The design of the study was a consecutive sample trial.

SETTING

The study took place in a university hospital.

PATIENTS

41 intubated patients of a surgical ICU who received netilmicin as a short-term infusion over 30 min for life-threatening infections were included in the study.

INTERVENTIONS

In 21 patients netilmicin was administered t.i.d. The virtual peak levels which had been determined by pharmacokinetic dosage calculation were compared with the serum concentrations obtained directly after the administration as well as after 15, 30, 60 and 180 min. In 20 patients the netilmicin serum concentrations during od treatment were determined directly before and immediately after the application as well as 0.5, 1, 3, 7 and 12 h later. To achieve a virtual peak level of 25 mg/l and a trough level of 0.5 mg/l individual adjustment of the dosage based on pharmacokinetic calculations was performed.

MEASUREMENTS AND RESULTS

In t.i.d. treatment the serum concentration measured after 30 min was closest to the virtual peak level; therefore, this is the best time to determine the peak level. In od treatment the required daily dose was 7.86 mg/kg body weight (median) in patients with normal renal function. During od dosing the trough level was extremely important in drug monitoring, whereas determination of the high peak level was of doubtful value.

CONCLUSIONS

The peak level should be determined during t.i.d. administration at 30 min. In od treatment the initial daily dose should be 7 mg/kg body weight; in drug monitoring the trough level is very important.

Teicoplanin with other drugs: possible pharmacological interactions

The contemporaneous employment of two or more drugs may present the risk of modifying the required therapeutic effect or producing adverse reactions. These interactions are of a pharmacokinetic and pharmacodynamic type. Teicoplanin is an antibiotic with a glycopeptide structure, produced by Actinoplanes teichomyceticus, active against both anaerobic and aerobic Gram-positive bacteria that are resistant to various chemotherapeutic drugs (beta-lactam and macrolide antibiotics, tetracyclines, co-trimoxazole). Then the aim of this work was to verify experimentally the possible pharmacological interactions between teicoplanin and oral hypoglycemic (phenformin and glibenclamide), or oral anticoagulant (warfarin) or bronchodilator (theophylline) drugs. Teicoplanin (3-15 mg/kg/die i.p. for 4 days) administration to the rat did not significantly (p > 0.05) modify the glycemia, prothrombin and partial thromboplastin times, the hypoglycemic effect of phenformin (2.5 mg/kg/die os for 4 days) and glibenclamide (0.5 mg/kg/die os for 4 days) or the anticoagulant effect of warfarin (0.5 mg/kg/die os for 4 days); moreover it did not significantly (p > 0.05) modify the pharmacokinetics of aminophylline (5 mg/kg i.v.) on the rabbit. In conclusion our results documented that teicoplanin does not interfere with phenformin, glibenclamide, or sodium warfarin activities nor with aminophylline pharmacokinetics.

Treating bone and joint infections with teicoplanin: hospitalization vs outpatient cost issues

The relative cost of outpatient parenteral antibiotic treatment of bone and joint infections with the investigational drug teicoplanin was compared with the cost of inpatient treatment. A private practice infectious disease group used teicoplanin to treat 49 patients (53 treatment courses) with bone and joint infections. The outpatient treatment program "saved" $403,680 compared with inpatient treatment, based on per diem reimbursements of $700 for inpatient treatment and $220 for outpatient treatment. Any cost analysis should be interpreted carefully because accurate calculation of outpatient treatment savings requires distinguishing among actual costs, charges, and reimbursements. In addition, there may be hidden costs related to lack of efficacy, toxicity, or litigation. Consideration should also be given to whoever is the beneficiary of the savings. Is it the indemnity insurance company, the provider, or the patient? Specific characteristics of the treatment, including ease of use, effectiveness, and monitoring requirement, may affect the savings. Our study showed that teicoplanin allows once-daily dosing, is easily administered, is generally efficacious, and has minimum requirements for blood level monitoring. These characteristics improve the cost effectiveness of using the drug in an outpatient treatment program.

Cost implications of home care on serious infections

More than 250,000 Americans will receive home IV drug therapy this year. Antibiotics will account for two-thirds of this care. Over 60% of infections treated at home are caused by gram-positive cocci, with staphylococci accounting for approximately 24% of the pathogens. Bone and joint infections represent the most common diagnoses among patients receiving parenteral antibiotics at home, and many of the infections treated at home were initially acquired in the hospital. The most common serious complications of coronary bypass surgery, the most frequently performed operation in many hospitals, are sternal wound infections are methicillin-resistant The major pathogenic causes of these infections are methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis. These complications are usually treated with prolonged inpatient IV therapy and surgery. In a study in which patients with sternal wound infections or mediastinitis secondary to coronary bypass surgery were treated with teicoplanin, preliminary results showed that the mean postoperative hospital stay was decreased by more than 7 days compared with patients receiving other types of antibiotic therapy. This was accomplished by changing from intravenous to intramuscular therapy as soon as the patient became stabilized and then discharging the patient after an additional 2 days to complete intramuscular therapy at home. In addition to enhancing the quality of life for the patient by allowing early hospital discharge and early ambulation, home therapy offers the additional benefits of decreasing the risk of cross infection to other patients, as well as to the already infected patient.

Efficacy and pharmacokinetics of teicoplanin in hemodialysis patients

In order to establish guidelines for the dosage of teicoplanin, a new glycopeptide antibiotic, in patients with end stage renal failure, 40 cases of suspected or proven gram-positive infections were treated with teicoplanin. Three different dosage regimens were used and peak/trough serum levels measured. Thirty-one patients were cured and six patients died. Teicoplanin was well tolerated. For severe cases of septicemia with staphylococci in patients undergoing hemodialysis a teicoplanin therapy consisting of 800 mg on day 1 followed by administrations of 400 mg on days 2, 3, 5, 12, and 19 is recommended. Minor infections are treated initially with 800 mg followed by administration of 400 mg at weekly intervals.

A comparative study of enzymuria, in the rat, of the drug combinations amikacin/vancomycin and amikacin/teicoplanin

The aim of this study was to compare nephrotoxicity of the combinations amikacin/vancomycin and amikacin/teicoplanin. Eighteen male Wistar rats were divided into 3 groups of 6 animals each. The first group received 50 mg.kg-1 of amikacin (i.m. route) and 100 mg.kg-1 of vancomycin (i.p. route). The second group received 50 mg.kg-1 of amikacin (i.m. route) and 40 mg.kg-1 of teicoplanin (i.p. route). The third group received an isotonic solution of sodium chloride. The antibiotics were injected for a period of 6 days. Urine samples of animals were taken 24 h before the beginning of the experiment, then every day, throughout the duration of the treatment (6 days), continuing for an additional 3 days following completion of the administration of the drugs. There were no significant modifications in the urinary excretions of alanine aminopeptidase and the creatinine between the 3 groups; but in the group receiving amikacin/teicoplanin, we observed between days 3 and 8 an increase in the excretion of N-acetyl-beta-D- glucosaminidase when compared to the group receiving amikacin/vancomycin (p < or = 0.05) and to the control group (p < or = 0.01).