Population Pharmacokinetics of Teicoplanin and Its Dosing Recommendations for Neutropenic Patients With Augmented Renal Clearance for Hematological Malignancies

BACKGROUND

Plasma teicoplanin concentrations do not reach the therapeutic range in several patients with hematological malignancies. Nevertheless, the characteristics of the population pharmacokinetic (PPK) models have not been clarified for malignancy. The decrease in the teicoplanin concentration in patients with cancer has been attributed to augmented renal clearance (ARC). It is essential to identify the causative factors of ARC to construct a PPK model to optimize the administration method. The authors aimed to establish a PPK model and develop an appropriate dosing regimen for teicoplanin in patients with hematological malignancies.

METHODS

PPK analysis was performed using therapeutic drug monitoring (TDM) data from 119 patients with hematological malignancies. The developed model was verified by predictive performance.

RESULTS

The covariates affecting systemic clearance were serum creatinine, presence or absence of neutropenia (<500/μL), and body size descriptor. Patients with hematologic malignancies and neutropenia showed a 25% increase in clearance compared with those with a normal neutrophil count. The PPK model was constructed based on the presence or absence of neutropenia. This model allowed the selection of the most appropriate dosage regimen out of those recommended by the TDM guidelines for patients with eGFR of >60 mL/min/1.73 m2. The PPK model predicted a dosing regimen for achieving a 10% improvement in the coverage probability of the target concentration range during the loading and maintenance phases.

CONCLUSIONS

The PPK model may help optimize dose regimens and evaluate dosing methods, using comparative simulations, in patients with hematological malignancies.

Immunohistochemical localization and pharmacokinetics of the anti-MRSA drug teicoplanin in rat kidney using a newly developed specific antibody

We prepared a polyclonal antibody against a teicoplanin (TEIC)-bovine serum albumin conjugate that was specific to both conjugated and free forms of TEIC. We demonstrated that this antibody could be used to detect the time-dependent localization of TEIC in rat kidneys. Immunohistochemistry revealed immunoreactivity specifically in the microvilli and apical cytoplasm of epithelial cells in proximal tubule segments S1 and S2, 1 h after intravenous TEIC injection, with higher staining intensity in the S2 segments. The epithelial cells of S3 segments showed moderate immunostaining with a few cells exhibiting nuclear staining. Furthermore, we found that the distal tubules and collecting ducts contained both TEIC-positive and -negative cells. TEIC immunoreactivity decreased rapidly over time; only weak staining remained in the S3 segments, distal tubules, and collecting ducts 24 h after administration. No staining was detected 7 days after injection. These results were significantly different from those of our previous study obtained using vancomycin, which showed moderate staining in the proximal tubule segments S1 and S2, distal tubules, and the collecting ducts 8 days after administration. The lower TEIC accumulation in tissues may account for a lower risk of adverse events compared to that using vancomycin.

Therapeutic Drug Level Monitoring of Teicoplanin in Korean Pediatric Patients with Normal versus Impaired Renal Function

BACKGROUND

Teicoplanin is used to treat serious gram-positive infections. Optimal teicoplanin trough levels are considered to be ≥ 10 μg/mL. Despite its wide use in various clinical settings, data on teicoplanin trough level in pediatric patients are limited. Therefore, the aim of this study was to investigate the therapeutic drug level monitoring of teicoplanin in Korean pediatric patients, including those with impaired renal function.

METHODS

A retrospective study was performed in pediatric patients (age ≤ 18 years old) who received teicoplanin from September 2014 to April 2018. The regimen included a loading dose of 10 mg/kg/dose at 12 hours' interval three times in a row, and a maintenance dose of 10 mg/kg/dose commenced at 24 hours of interval after the loading dose, with a maximum of 400 mg/dose, respectively. The first therapeutic drug levels were measured. Distribution and characteristics of trough levels in patients with decreased renal function and those with bacteremia were also assessed.

RESULTS

A total of 187 trough levels were collected from 143 patients. Hematologic and oncologic diseases were the most common underlying diseases (83.2%, n = 119). One hundred eighty trough levels were first measured, and their median value was 16.2 μg/mL (range, 2.3-100 μg/mL) and the median interval between initial teicoplanin injection and 1st trough level was 96.5 hours (range 47.6-179.3 hours). Lower steady-state levels were observed in younger age group (median, 13.5 vs. 18.0 μg/mL, P = 0.038). Median trough levels were higher in patients with decreased renal functions (P < 0.001). In addition, among eight with gram-positive bacteremia, seven of them had a favorable outcome.

CONCLUSION

This study provides additive information on trough level monitoring of teicoplanin in children with impaired renal function and treatment effect in patients with gram-positive bacteremia. Careful monitoring for steady state trough levels of teicoplanin is warranted.

Streptococcus dysgalactiae septic arthritis of sternoclavicular joint with bacteraemia

Invasive infections due to Streptococcus dysgalactiae are uncommon in the adult population, and sternoclavicular joint septic arthritis (SCSA) is usually caused by other organisms such as Staphylococcus aureus and Pseudomonas aeruginosa. We hereby report a case of SCSA caused by this organism. The patient responded well to intravenous antibiotics and recovered fully without any surgical intervention.

Brain abscess in a patient with psoriatic arthritis treated with adalimumab: A case report

RATIONALE

In patients receiving biological therapies, serious infections are a major concern. Infections associated with anti-tumor necrosis factor antibody therapy include tuberculosis, viral, fungal, and bacterial infections. Likewise, severe infections of the upper and lower respiratory tract, lung, skin and soft tissue, urinary tract, gastrointestinal tract, joint, and bone have also been reported previously. However, infections involving the central nervous system are rare, especially an intracranial infection caused by odontogenic infection. To date, only few cases have been reported of this infection. This is the first case of a patient with psoriatic arthritis receiving adalimumab and developing brain abscess of odontogenic origin.

PATIENT CONCERNS

A 39-year-old male with psoriatic arthritis receiving adalimumab treatment came to the emergency department with initial presentation of sudden onset convulsions. He had been receiving adalimumab treatment for 1 month. Two days after the third injection, the patient had an episode of sudden-onset general convulsion for nearly 5 min with the upgazing and general tonic presentation. Magnetic resonance imaging (MRI) showed left frontal lobe brain abscess. Pus culture from the brain abscess detected Streptococcus sanguinis (S. sanguinis), Fusobacterium nucleatum (F. nucleatum), and Parvimonas micra (P. micra).

DIAGNOSIS

Brain abscess with odontogenic infection.

INTERVENTIONS

The patient received left frontal craniotomy, abscess drainage and systemic empiric antibiotics treatment with vancomycin, cefepime, and metronidazole. Due to drug rash with eosinophilia and systemic symptoms during the treatment, vancomycin and metronidazole were discontinued, and systemic antibiotics were switched to teicoplanin and ceftriaxone.

OUTCOMES

A brain MRI follow-up performed after 1 month of initial treatment revealed the reduced size of the abscess lesion and minimal oedema. The patient was discharged with stable condition.

LESSONS

To the best of our knowledge, this is the first case of a patient with psoriatic arthritis receiving adalimumab and developing brain abscess of odontogenic origin. Such a rare diagnosis must be kept in mind when patients treated with adalimumab present with sudden-onset convulsions. Careful dental examination should be performed before administration of adalimumab.

[Infected hepatic cyst in ADPKD patient in peritoneal dialysis]

Renal and hepatic cysts infections are among the most important infectious complications of ADPKD and often require hospitalization. Liver cysts are even more complex than renal cysts and their diagnosis and treatment are quite controversial. We report the case of a 58-year-old patient with ADPKD undergoing peritoneal dialysis treatment. He presented fever and severe asthenia and was diagnosed with a hepatic cyst infection. Given the presence of the peritoneal catheter, and in order to facilitate the targeted treatment of the infection, we administered antibiotics (ceftazidime and teicoplanin) in the bags used for peritoneal dialysis exchanges for 4 weeks, obtaining the complete disappearance of symptoms and laboratory and ultrasound alterations. Intraperitoneal antibiotics administration in the treatment of infected hepatic cysts represents an effective and safe therapeutic alternative, never described in literature so far.

Risk factors for decreased teicoplanin trough concentrations during initial dosing in critically ill patients

Aim of the study: Here, we investigated the risk factors for decreased teicoplanin plasma trough concentrations relative to the initial dosing in critically ill patients. Patients and methods: Data obtained from 80 eligible critically ill patients who received intravenous teicoplanin were retrospectively analyzed. Risk factors for decreases in teicoplanin trough concentrations 72 h after administration of teicoplanin of more than 30% relative to predicted concentrations based on initial dosing setting were identified by logistic regression analysis. Results: Although prediction trough concentration and total dose of two days no significant differences were seen between the variation group and the non-variation group, actual trough concentration was significantly different between two groups (19.9±5.6 μg/ml vs 10.3±2.2 μg/ml, p < 0.001). In multivariate analysis, serum albumin ≤ 2.2 mg/dl (odds ratio [OR] = 3.003, 95% CI 1.072-8.408; p = 0.036) and SOFA score ≥ 9 (OR = 3.498, 95% CI 1.171-10.450; p = 0.025) were significant risk factors for decreased teicoplanin plasma trough concentrations. Conclusion: In critically ill patients, high SOFA score and low serum albumin were risk factors for decreased teicoplanin plasma trough concentration during initial dosing.

Is Intraarticular Antibiotic Administration Effective in the Treatment of Methicillin-Resistant Staphylococcus aureus?

PURPOSE OF THE STUDY Septic arthritis is an infection of joints caused by a pathogenic microorganism. Septic arthritis has a mortality rate of 11-40% when it's not treated properly. The mortality rate with methicillin-sensitive Staphylococcus aureus (MSSA)is 5-7%, while the rate with methicillin-resistant Staphylococcus aureus (MRSA)is 13-20%. The aim of this study is to evaluate the effects of intraarticular vancomycin and teicoplanin on joint cartilage in in vivo settings and its utility in routine MRSA treatment. MATERIALS AND METHODS In our study, 35 male Sprague-Dawley rats aged 28 days were used. Rats were obtained from the Regenerative and Restorative Medicine Research Center (REMER) of Istanbul Medipol University. Rats were randomly divided into 5 groups each containing 7 rats. Joint injections were administered with isoflurane analgesia every day at 6 am. Three rats (15 rats) from each group were sacrified in seventh day and evaluated immunohistologically to evaluate acute healing in articular cartilage. All remaining rats were sacrificed on day 28 and their knees were evaluated by immunohistochemical examination. RESULTS In our study, there were no complications in any rat during injection and the study period. Hematoxylin eosin (H & E) histological staining for evaluating cartilage healing and healing levels did not show statistically significant differences between the groups at first week (p > 0.05). Matrix metalloproteinase-13 (MMP-13) staining did not show any statistically significant difference between the groups. (p > 0.05). DISCUSSION MRSAseptic arthritis, diagnosed for the first time in 1960, has recently been responsible for 6-22% of all septic arthritis and is increasing day by day. The use of systemic vancomycin or teicoplanin is the first-line treatment method in MRSA septic arthritis. Serum levels reach the desired level, especially with intravenous infusion dose. On the other hand, it has been shown that intraarticular concentration does not reach a sufficient level in studies conducted. The use of intraarticular antibiotics during treatment can lead to more effective and early disease control by turning this negative situation into favor of the patient. As a result, intraarticular vancomycin and teicoplanin maximale tolerable and maintenance doses can be safely used beside surgery and intravenous antibiotics to increase efficacy of treatment, reduction of recurrence rates and reduction of mortality in MRSAseptic arthritis. CONCLUSIONS Intraarticular vancomycin and teicoplanin maximale tolerable and maintenance doses can be safely used beside surgery and intravenous antibiotics to increase efficacy of treatment, reduction of recurrence rates and reduction of mortality in MRSA septic arthritis. Key words:arthritis, infectious; methicillin-resistant Staphylococcus aureus; mortality.

A simplified chart for determining the initial loading dose of teicoplanin in critically ill patients

AIM OF THE STUDY

A simplified chart to determine the initial loading dose of teicoplanin (TEIC chart) for achieving the target trough concentration was developed. The aim of the present study was to evaluate the usefulness of this chart in critically ill patients.

PATIENTS AND METHODS

The initial loading dose and maintenance dose to achieve a target trough concentration ≥10 μg/mL on day 4 was determined using the teicoplanin TDM software and presented in a TEIC chart. The dosage of teicoplanin, including the loading dose for the first 2 days and the maintenance dose thereafter, was selected from the chart (chart method, N = 41) or calculated using TDM software (software method, N = 39).

RESULTS

The performance rate of initial loading of teicoplanin increased from 83.0% to 100% after the TEIC chart was introduced (P = 0.016). The TEIC chart significantly reduced the time required for determining the initial loading dose compared with the use of software (1.9±0.6 min vs. 29.7±13.8 min, P < 0.001). No significant differences were observed in the rates of achieving a target level ≥10 μg/mL (P = 0.766).

CONCLUSION

The TEIC chart enables a simple, rapid, and reliable determination of teicoplanin dosage.

Population pharmacokinetics and pharmacodynamics of teicoplanin in neonates: making better use of C-reactive protein to deliver individualized therapy

OBJECTIVES

There is uncertainty about the optimal teicoplanin regimens for neonates. The study aim was to determine the population pharmacokinetics (PK) of teicoplanin in neonates, evaluate currently recommended regimens and explore the exposure-effect relationships.

METHODS

An open-label PK study was conducted. Neonates from 26 to 44 weeks post-menstrual age were recruited (n = 18). The teicoplanin regimen was a 16 mg/kg loading dose, followed by 8 mg/kg once daily. Therapeutic drug monitoring and dose adjustment were not conducted. A standard two-compartment PK model was developed, followed by models that incorporated weight. A PK/pharmacodynamic (PD) model with C-reactive protein serial measurements as the PD input was fitted to the data. Monte Carlo simulations (n = 5000) were performed using Pmetrics. The AUCs at steady state and the proportion of patients achieving the recommended drug exposures (i.e. Cmin >15 mg/L) were determined. The study was registered in the European Clinical Trials Database Registry (EudraCT: 2012-005738-12).

RESULTS

The PK allometric model best accounted for the observed data. The PK parameters medians were: clearance = 0.435 × (weight/70)0.75 (L/h); volume = 0.765 (L); Kcp = 1.3 (h-1); and Kpc = 0.629 (h-1). The individual time-course of C-reactive protein was well described using the Bayesian posterior estimates for each patient. The simulated median AUC96-120 was 302.3 mg·h/L and the median Cmin at 120 h was 12.9 mg/L; 38.8% of patients attained a Cmin >15 mg/L by 120 h.

CONCLUSIONS

Teicoplanin population PK is highly variable in neonates, weight being the best descriptor of PK variability. A low percentage of neonates were able to achieve Cmin >15 mg/L. The routine use of therapeutic drug monitoring and improved knowledge on the PD of teicoplanin is required.

Vancomycin, teicoplanin, daptomycin, and linezolid MIC creep in methicillin-resistant Staphylococcus aureus is associated with clonality

The purpose of this study is to evaluate the susceptibility trend of vancomycin, teicoplanin, daptomycin, and linezolid against methicillin-resistant Staphylococcus aureus (MRSA) blood isolates of different clones over an 11-year period.From 2000 to 2010, all bloodstream MRSA isolates from Chang Gung Memorial Hospital in Taiwan were prospectively collected. Three periods, namely 2000 to 2001, 2004 to 2005, and 2010, were included and 124 MRSA isolates were selected from each period. Minimum inhibitory concentrations (MICs) were determined by E-test. All the isolates were molecularly characterized.MRSA molecular epidemiology evolved from 1 predominant pulsotype (type A) to 5 major pulsotypes of 3 clonal complexes (CC). Vancomycin, teicoplanin, and daptomycin MICs creep were observed, particularly for pulsotype A-CC 239-staphylococcal cassette chromosome mec (SCCmec) III though its prevalence dramatically decreased since 2004 to 2005. Throughout the study period, the overall vancomycin modal MIC was stable at 1.5 mg/L, but teicoplanin and linezolid modal MIC increased to 2 and 2 mg/L, respectively. Isolates with teicoplanin and linezolid ≧ 2 ug/mL belonged to multiple clones. Pulsotype F-ST5-SCCmec II with a high rate of teicoplanin MIC ≧ 2 ug/mL continued clonal spread. Teicoplanin MIC had a high correlation with linezolid MIC.Molecular epidemiology MRSA bloodstream isolates in northern Taiwan evolved from 2000 throughout 2010, which was subsequently associated with the changing distribution of antibiotic MICs. While vancomycin MIC level remained unchanged, teicoplanin, daptomycin, and linezolid MIC levels increased. The impact of these changes on clinical treatment response deserves further investigations.

Changing modalities of outpatient parenteral antimicrobial therapy use over time in Italy: a comparison of two time periods

This study aimed to assess the extent and nature of recent changes in the management of outpatient parenteral antimicrobial therapy (OPAT) in Italy. We reviewed our previously reported data from 1999 to 2003 and compared them with data from patients who received OPAT from 2005 to 2010. Data for 1175 patients who received OPAT were analysed. Skin and soft tissue infections (SSTIs) were the most common infection treated with OPAT in both time periods, but an increase in patients with SSTIs receiving OPAT was observed. By contrast, a decline over time of OPAT use was found for patients affected by pneumonia. Furthermore, ceftriaxone use declined, whereas teicoplanin increased over time. In conclusion, OPAT use has significantly changed over time in Italy.

Once-weekly dalbavancin versus daily conventional therapy for skin infection

BACKGROUND

Dalbavancin, a lipoglycopeptide antibiotic agent that is active against gram-positive pathogens, has a long plasma half-life, allowing for once-weekly dosing. DISCOVER 1 and DISCOVER 2 were identically designed noninferiority trials of dalbavancin for the treatment of acute bacterial skin and skin-structure infection.

METHODS

We randomly assigned patients to receive dalbavancin intravenously on days 1 and 8 or vancomycin intravenously for at least 3 days with the option to switch to oral linezolid to complete 10 to 14 days of therapy. The primary end point, early clinical response, required the cessation of spread of infection-related erythema and the absence of fever at 48 to 72 hours. Secondary end points at the end of therapy included clinical status and investigator's assessment of outcome.

RESULTS

Analysis of the primary end point showed noninferiority of dalbavancin in both DISCOVER 1 and DISCOVER 2. In the pooled analysis, 525 of 659 patients (79.7%) in the dalbavancin group and 521 of 653 (79.8%) in the vancomycin-linezolid group had an early clinical response indicating treatment success (weighted difference, -0.1 percentage point; 95% confidence interval, -4.5 to 4.2). The outcomes were similar in the analyses by study and the pooled analyses of clinical status at the end of therapy and the investigator's assessment of outcome. For patients infected with Staphylococcus aureus, including methicillin-resistant S. aureus, clinical success was seen in 90.6% of the patients treated with dalbavancin and 93.8% of those treated with vancomycin-linezolid. Adverse events and study days with an adverse event were less frequent in the dalbavancin group than in the vancomycin-linezolid group. The most common treatment-related adverse events in either group were nausea, diarrhea, and pruritus.

CONCLUSIONS

Once-weekly intravenous dalbavancin was not inferior to twice-daily intravenous vancomycin followed by oral linezolid for the treatment of acute bacterial skin and skin-structure infection. (Funded by Durata Therapeutics; DISCOVER 1 and DISCOVER 2 ClinicalTrials.gov numbers, NCT01339091 and NCT01431339.).

Variability in protein binding of teicoplanin and achievement of therapeutic drug monitoring targets in critically ill patients: lessons from the DALI Study

The aims of this study were to describe the variability in protein binding of teicoplanin in critically ill patients as well as the number of patients achieving therapeutic target concentrations. This report is part of the multinational pharmacokinetic DALI Study. Patients were sampled on a single day, with blood samples taken both at the midpoint and the end of the dosing interval. Total and unbound teicoplanin concentrations were assayed using validated chromatographic methods. The lower therapeutic range of teicoplanin was defined as total trough concentrations from 10 to 20 mg/L and the higher range as 10-30 mg/L. Thirteen critically ill patients were available for analysis. The following are the median (interquartile range) total and free concentrations (mg/L): midpoint, total 13.6 (11.2-26.0) and free 1.5 (0.7-2.5); trough, total 11.9 (10.2-22.7) and free 1.8 (0.6-2.6). The percentage free teicoplanin for the mid-dose and trough time points was 6.9% (4.5-15.6%) and 8.2% (5.5-16.4%), respectively. The correlation between total and free antibiotic concentrations was moderate for both the midpoint (ρ = 0.79, P = 0.0021) and trough (ρ = 0.63, P = 0.027). Only 42% and 58% of patients were in the lower and higher therapeutic ranges, respectively. In conclusion, use of standard dosing for teicoplanin leads to inappropriate concentrations in a high proportion of critically ill patients. Variability in teicoplanin protein binding is very high, placing significant doubt on the validity of total concentrations for therapeutic drug monitoring in critically ill patients.

Teicoplanin as an anti-methicillin resistant Staphylococcus aureus agent in infections of severely poisoned intensive care unit patients/ Tehran- Iran

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia is related to high morbidity and mortality. Glycopeptide antibiotic is the choice of treatment in MRSA infections. Teicoplanin is a semi synthetic glycopeptide antibiotic with a spectrum of activity similar to vancomycin.  Our objective is the evaluation of efficacy and safety of Teicoplanin in MRSA infections among severely poisoned intensive care unit (ICU) patients.

METHOD

During a 6 months period, in a prospective cross sectional study 54 eligible patients from 80 clinically suspicious with MRSA infections were recruited. The efficacy and safety of Teicoplanin was evaluated 5 times. The clinical findings, laboratory data, and bacteriologic responses were defined as cure, improvement and failure.

RESULTS

The mean age of the patients was 36.3 years (range, 20-72, SD = 13.3). 75.9% were male. Suicidal attempts were recorded in 63%. The most common poisoning was TCAs, BZDs, tramadol and opium. 94.4% were unconscious and under mechanical ventilation. Tracheal cultures were positive in 98.1% by VAP diagnosis. Length of stay in the ICU was between  4-54 days. Total clinical effectiveness was 90.4%, and failure 9.6%. Mortality rate of the patient, was 9/54 (16.6 %) which 3 of them were for lack of a clinical response. On the fourth visit, the adverse effects included: rash (11.10%), anemia (36.17%), nephrotoxicity (17.02%) and thrombocytopenia &lt; 150000 (100%). Other side effects such as: leucopenia, severe thrombocytopenia (&lt; 50000), pancytopenia and red man syndrome were not detected.

CONCLUSIONS

Teicoplanin is suggestible for MRSA infections among severely poisoned patients according to its efficacy, safety, half life and tolerance.

MultiresistantStenotrophomonas maltophiliaTunneled CVC-Related Sepsis, Treated with Systemic and Lock Therapy

In the last decade, a remarkable increase in the incidence of nosocomial Gram-negative infections has been observed. These pathogens represent a substantial problem in clinical practice, due to the high resistance profile of most commonly used antibiotics. This phenomenon is surely a co-factor that exposes these susceptible patients to infections caused by selected pathogens like multiresistant Gram-negative rods. A typical example is represented by VAP (ventilator-associated pneumonia) sustained by Acinetobacter spp., Pseudomonas aeruginosa, Bulkolderia cepacia. The Authors describe a case of a central venous cather (CVC)-related Stenotrophomonas maltophilia sepsis in a patient affected by solid tumor, successfully treated with systemic antibiotic therapy associated with "lock therapy". This combination was able to cure the infection, allowing the patient to continue chemotherapy and saving the in situ CVC. The surveillance of CVCs, good adherence to the protocols and guidelines and "good practice" are the cornerstones for the prevention of nosocomial infections.

Combined Therapy of Teicoplanin and Caffeic Acid Phenethyl Ester (CAPE) in the Treatment of Experimental Mediastinitis in the Rat

Post-sternotomy mediastinitis affects 1-3% of patients undergoing cardiac surgery and is lethal in 10-47% of these patients. We investigated the effect of an antioxidant/anti-inflammatory agent, caffeic acid phenethyl ester (CAPE), in the attenuation of inflammatory response induced by methicillin-resistant Staphylococcus aureus (MRSA) infection in a rat experimental mediastinitis model. Rats, divided into six equal groups, received MRSA precolonized stainless steel wire pieces implanted into their mediastinal spaces. Control group and CAPE control group received saline and CAPE 10 micromol/kg.day(-1 )respectively, where Group A received a single dose of teicoplanin 24 mg/kg i.m. for the first day and then 12 mg/kg.day(-1) . Group B received teicoplanin as in Group A plus CAPE 10 micromol/kg. day(-1 )intra-peritoneally. Group C received teicoplanin 60 mg/kg i.m. for the first day and then 30 mg/kg.day(-1 )and Group D received teicoplanin as in Group C plus CAPE 10 micromol/kg.day(-1) . By the end of 14 days rats were sacrificed and serum malondialdehyde (MDA), myeloperoxidase (MPO), nitric oxide (NO), urea and creatinine levels were evaluated. Mediastinal organ tissues were collected for histopathological analysis. Infection rates in all the drug-treated groups were lower than the control groups ( P=0.002) but statistical significance was attained only between the groups A and D ( P=0.018). In connective tissues and the peribronchial area polymorphonuclear leukocytic (PNL) infiltration in the treatment groups, although becoming very close, did not reach statistical significance (P =0.053, P=0.075, respectively). PNL infiltration especially in the peribronchial tissues of the Group B animals was found to be significantly less than the Control and CAPE Control groups with P values of 0.013 and 0.010, respectively. MDA and MPO levels were significantly lower in the treatment groups ( P<0.001 and P<0.001 respectively). Levels of the degradation products of NO were lower in treatment groups compared to two control groups (P=0.003, P= 0.005). NO levels in Group D were lowest among all treatment groups ( P=0.001). It has been demonstrated that although bacterial colonization can be controlled in mediastinitis, the inflammatory response persists. The combination of an antioxidant / anti-inflammatory agent, CAPE, added to standard antibiotic therapy might be effective in the treatment of post-sternotomy mediastinitis due to MRSA.

Influence of teicoplanin MICs on treatment outcomes among patients with teicoplanin-treated methicillin-resistant Staphylococcus aureus bacteraemia: a hospital-based retrospective study

OBJECTIVES

Higher vancomycin MIC values (≥1.5 mg/L via Etest) may be associated with vancomycin treatment failure among patients with serious methicillin-resistant Staphylococcus aureus (MRSA) infections. As there were limited similar data for teicoplanin, this retrospective cohort study intended to determine the predictive value of teicoplanin MICs for treatment failure among patients with MRSA bacteraemia.

PATIENTS AND METHODS

All patients with at least one blood culture positive for MRSA admitted to the hospital between January 2010 and January 2011 were reviewed. Patients with an age ≥18 years and receipt of teicoplanin therapy throughout the course or receipt of <72 h of vancomycin therapy and then teicoplanin for >3 days were enrolled. Teicoplanin Etest(®) MICs and treatment outcomes for MRSA bacteraemia were reviewed to identify the breakpoint of teicoplanin MICs influencing treatment outcomes.

RESULTS

Of the 101 patients enrolled, 56 had a lower teicoplanin MIC (≤1.5 mg/L) for MRSA and 45 had a higher MIC (>1.5 mg/L) for MRSA. A lower teicoplanin MIC was associated with a favourable outcome [37 (66.1%) versus 13 (28.9%); P<0.001] and a lower rate of bloodstream infection-related mortality [15 (26.8%) versus 22 (48.9%); P=0.022]. Patients with chronic obstructive pulmonary disease, bacteraemic pneumonia or higher Pittsburgh bacteraemia score had an unfavourable outcome (P=0.028, 0.022 and <0.001, respectively). Multivariate analysis showed that teicoplanin MIC >1.5 mg/L, higher Pittsburgh bacteraemia score and bacteraemic pneumonia were independent risk factors for unfavourable outcome.

CONCLUSIONS

A higher teicoplanin MIC value (>1.5 mg/L) may predict an unfavourable outcome and higher mortality rate among teicoplanin-treated MRSA bacteraemic patients.

Teicoplanin dosing strategy for treatment of Staphylococcus aureus in Korean patients with neutropenic fever

PURPOSE

The present study was conducted to determine and compare the target attainment rate (TAR) between microorganism-nonspecific (C(trough)) and microorganism- specific (AUC24/MIC) targets over two weeks of teicoplanin administration according to several dose regimens for the treatment of Staphylococcus aureus in Korean patients with neutropenic fever.

MATERIALS AND METHODS

One thousand virtual concentrations were obtained for each dose using the population pharmacokinetic parameters of teicoplanin adopted from a published study. Simulation of 1,000 virtual MICs was performed using the MICs of 78 clinical isolates of S. aureus collected from a hospital in Korea. Thereafter, these simulated MICs were randomly allocated to 1,000 virtual patients in whom the TARs for AUC24/MIC>125 [or 345] and C(trough)>10 [or 20] mg/L were determined. The relationship of the maintenance dose with the steady-state TAR was predicted with respect to the AUC24/MIC>125 [or 345] using logistic analysis.

RESULTS

The standard dose regimen of teicoplanin showed TARs of about 70% [or 33%] and 70% [or 20%] at steady-state in cases with AUC24/MIC>125 [or 345] and C(trough)>10 [or 20] mg/L, respectively.

CONCLUSION

The current standard dose regimen was predicted to be insufficient to adequately treat S. aureus in Korean patients with neutropenic fever. To assure at least an 80% TAR in this population, dose adjustment of teicoplanin should be considered.

The appropriate medical management of methicillin-resistant Staphylococcus aureus in chronic suppurative otitis media

CONCLUSION

Methicillin-resistant Staphylococcus aureus (MRSA) was the most prevalent species (28.1%) in the bacteriological study of 577 patients with chronic suppurative otitis media (CSOM). Frequent and appropriate aural cleansing and irrigation using diluted acetic acid or other solutions such as Burow's solution can be an effective method for the medical treatment of MRSA in CSOM.

OBJECTIVES

To investigate the bacteriological results of 577 patients with CSOM and the medical treatment results of 91 non-cholesteatomatous MRSA patients and to consider the most appropriate medical treatment modality for MRSA in patients with CSOM.

PATIENTS AND METHODS

This study was conducted retrospectively from January 2005 through July 2008 using the medical records of 577 patients with otorrhoea caused by CSOM. We analyzed the bacteriological results by dividing all patients into cholesteatomatous CSOM and non-cholesteatomatous CSOM and investigated the medical treatment results of 91 non-cholesteatomatous MRSA patients. We used three treatment modalities: aural cleansing and irrigation (50 cases), intravenous injection of teicoplanin (22 cases) and intravenous injection of vancomycin (15 cases).

RESULTS

Overall, MRSA (28.1%) was the most prevalent species, followed by methicillin-susceptible Staphylococcus aureus (MSSA) (20.4%), Pseudomonas (18.6%) and coagulase-negative staphylococci (CNS) (15.0%). In non-cholesteatomatous MRSA treatment for dry ear, there were no significant differences between the three groups. The results showed that 79.5% of the group treated with aural cleansing and irrigation succeeded in achieving dry ears in 19.0 days. Similarly, 78.9% of another group with intravenous injection of teicoplanin eventually had dry ears, taking 16.0 days. Finally, the number of patients with dry ear in the group treated with intravenous injection of vancomycin was up to 80% of the total in 15.2 days.

Outpatient parenteral antimicrobial therapy: Recent developments and future prospects

Patients with serious infections requiring parenteral antimicrobial therapy are usually hospitalized for treatment. For certain conditions, however, administration of parenteral antibiotics outside the hospital setting may be safe, efficacious, convenient for patients and cost-beneficial. Outpatient parenteral antimicrobial therapy (OPAT) was developed in the US initially and its use has expanded globally during the past three decades. A wide variety of infections are amenable to treatment by OPAT. Once-daily agents such as ceftriaxone or teicoplanin and, more recently, antimicrobials such as ertapenem or daptomycin have been used for OPAT. The use of higher doses and less-frequent dosing of existing agents is being explored, and exciting new developments include the emergence of agents with broader-spectrum activity against drug-resistant organisms and the use of antifungal agents in the OPAT setting. Future prospects in OPAT include the use of more recently launched drugs such as telavancin, as well as drugs in development, including dalbavancin (Durata Therapeutics Inc) and omadacycline (PTK-0796; Novartis AG/PARATEK Pharmaceuticals Inc). This review outlines recent developments in, and future prospects for, the antimicrobial agents used in OPAT.

Novel borate glass/chitosan composite as a delivery vehicle for teicoplanin in the treatment of chronic osteomyelitis

Composite materials composed of borate bioactive glass and chitosan (designated BGC) were investigated in vitro and in vivo as a new delivery system for teicoplanin in the treatment of chronic osteomyelitis induced by methicillin-resistant Staphylococcus aureus (MRSA). In vitro, the release of teicoplanin from BGC pellets into phosphate-buffered saline (PBS), as well as its antibacterial activity, were determined. The compressive strength of the pellets was measured after specific immersion times, and the structure of the pellets was characterized using scanning electron microscopy and X-ray diffraction. In vivo, the tibial cavity of New Zealand White rabbits was injected with MRSA strain to induce chronic osteomyelitis, treated by debridement after 4weeks, implanted with teicoplanin-loaded BGC pellets (designated TBGC) or BGC pellets, or injected intravenously with teicoplanin. After 12weeks' implantation, the efficacy of the TBGC pellets for treating osteomyelitis was evaluated using hematological, radiological, microbiological and histological techniques. When immersed in PBS, the TBGC pellets provided a sustained release of teicoplanin, while the surface of the pellets was converted to hydroxyapatite (HA). In vivo, the best therapeutic effect was observed in animals implanted with TBGC pellets, resulting in significantly lower radiological and histological scores, a lower positive rate of MRSA culture, and an excellent bone defect repair, without local or systemic side effects. The results indicate that TBGC pellets are effective in treating chronic osteomyelitis by providing a sustained release of teicoplanin, in addition to participating in bone regeneration.

The levels of cytokines in rats following the use of prophylactic agents in vascular graft infection

OBJECTIVES

The aim of this study was to investigate the circulating levels of IL-1, IL-6, IL-10 and TNF-? in serum following the use of topical and intra-peritoneal vancomycin and teicoplanin, as well as topical fusidic acid to prevent MRSA vascular graft infection in a rat model.

METHODS

Graft infections were established in the subcutaneous tissue of rats by implantation of Dacron prostheses. Circulating levels of IL-1, IL-6, IL-10 and TNF-alpha were measured in serum samples of all rats obtained by ELISA at sacrifice.

RESULTS

The mean serum levels of IL-1, IL-6 and IL-10 were found indifferent in all groups. The mean serum levels of TNF-alpha were as follows: 32.9 +/- 9.9 pg/ml in uncontaminated control group, 59.9 +/- 7.1 pg/ml in untreated contaminated group, 41.4 +/- 11.5 pg/ml in intraperitoneal vancomycin group, 39.6 +/- 10.1 pg/ml in intraperitoneal teicoplanin group, 35.6 +/- 8.2 pg/ml in topical vancomycin group, 37.3 +/- 19.5 pg/ml in topical teicoplanin group, 35.5 +/- 16.7 pg/ml in topical 10% fusidic acid group, 36.4 +/- 6.9 pg/ml in topical 40% fusidic acid group. The level of TNF-alpha in untreated contaminated group was significantly higher than in all of the other groups (p < 0.01, p < 0.05, p < 0.02, p < 0.01, p < 0.01, p < 0.01, p < 0.01, respectively).

CONCLUSION

TNF-alpha was determined to be a more accurate cytokine than IL-1, IL-6 and IL-10 in a rat model in which intra-peritoneal and topical glycopeptides as well as fusidic acid were administered for the prevention of vascular graft infection (Tab. 3, Fig. 2, Ref. 20).

Teicoplanin in combination: role in the management of the febrile neutropenic patient

The spectrum of microorganisms responsible for infection in neutropenic patients has changed in the last decade, with Gram-positive organisms now predominant. New antibiotic strategies have been required and have evolved to cope with this change. In particular, the optimal timing of glycopeptide antibiotic use has been addressed. Both teicoplanin and vancomycin are highly effective agents for susceptible Gram-positive organisms. Teicoplanin has advantages in terms of ease of administration and lower toxicity, while vancomycin has proved durable over many years' use. There are now firm indications for the use of glycopeptide antibiotics in febrile neutropenic patients, including clinically defined central venous catheter infection and microbiologically documented infection with susceptible organisms. The empirical use of the glycopeptide antibiotics in combination with other agents as first-line treatment, however, is less certain. The utility of this approach remains controversial and ultimately depends on the extent to which local practice favours the emergence of Gram-positive infections in neutropenic patients.

Teicoplanin in home therapy of the terminally ill child

Children discharged in the terminal phase of illness were offered the possibility of having central venous line infections treated with teicoplanin at home by their parents after suitable instruction. The decision to begin antibiotic treatment was subjective, based on a history of rigors and/or raised temperature in an otherwise "well" child. No difficulties were encountered in instructing the chosen parents. In all, five treatment periods of 7 days were required in the five children selected. The review time was 31 weeks (mean duration, 6.2 weeks/patient; range, 4-12 weeks), ended in all cases by death. Infection occurred a mean of 3.2 weeks after discharge (range, 1-8 weeks), and all episodes were successfully treated at home without hospital admission or ward-based support. No deaths occurred as a result of antibiotic therapy failure, and there were no clinically relevant side-effects. Autopsy confirmed the absence of central venous line infection in one patient, but blood culture was positive for Staphylococcus aureus in another. This study shows that home treatment of line infections with teicoplanin is effective and well tolerated, and offers advantages in terms of quality of life and parent-child relationships.

A prospective randomized study of prophylactic teicoplanin to prevent early Hickman catheter-related sepsis in patients receiving intensive chemotherapy for haematological malignancies

In all, 88 patients with haematological malignancies requiring Hickman catheters for intensive chemotherapy were randomized to receive either one single bolus intravenous injection of teicoplanin, 400 mg, or no teicoplanin immediately before insertion of a double-lumen Hickman catheter. Lower incidences of catheter-related Gram-positive sepsis were recorded in patients receiving prophylactic teicoplanin; exit site infection, tunnel infection and catheter-related Gram-positive septicaemia were all reduced. The benefit of prophylactic teicoplanin was observed particularly among patients who were already neutropenic at the time of catheterization. All Gram-positive organisms isolated from infected skin sites or from blood cultures taken from Hickman catheters were susceptible to teicoplanin. No adverse reaction was reported in any of the patients receiving prophylaxis. Prophylactic teicoplanin, therefore, may be used routinely for patients requiring insertion of Hickman catheters for intensive chemotherapy, to reduce the early incidence of catheter-related sepsis, particularly during the period of neutropenia following chemotherapy.

Acute kidney injury due to rhabdomyolysis-associated gangrenous myositis

Rhabdomyolysis is associated with infectious diseases in approximately 5% of cases and acute kidney injury occurs in 33-50% of cases. Gangrenous myositis is a deep seated infection of the subcutaneous and muscular tissues. We report the case of an 18 year-old man who was admitted to the emergency room with leg pain, fever, nausea, vomiting and oliguria. Physical examination showed moderate dehydration, peripheral cyanosis and skin necrosis with severe myalgia and no subcutaneous gas. Laboratory findings at admission were: serum urea 111 mg/dL, creatinine 1.3 mg/dL, potassium 6.3 mEq/L, creatine kinase (CK) 112,452 IU/L, aspartate amino transaminase (AST) 1116 IU/L, alanine amino transaminase (ALT) 1841 IU/L, pH 7.31, bicarbonate (HCO3) 11 mEq/L and lactate 4.3 mmol/L. Emergency hemodyalisis was started, and antibiotics were given due to high suspicion for bacterial infection. The patient developed respiratory insufficiency and septic shock needing mechanical ventilation and vasoactive drugs. He presented spontaneous gangrenous myositis in both legs and in his left arm. After 26 sessions of hemodialysis, partial recovery of renal function was observed. He was discharged from the ICU after 38 days, still with leg pain. Acute kidney injury due to rhabdomyolysis should be considered as a possible complication of gangrenous myositis.

Effect of antibiotic loading on the shear strength at the stem-cement interface (Shear strength of antibiotic loaded cement)

The purpose of this study was to investigate the effects of addition of antibiotics into cement powder on the shear properties of the cement-metal interface. The approach involved adding 800 mg of teicoplanin to 40 g bone cement powder in the t-800 group, 1,600 mg teicoplanin in the t-1,600 group, and no antibiotic in the control group. Industrially prepared bone cement containing 500 mg of gentamicin was used as group g-500. Each group consisted of ten samples. Cement-metal interfaces were produced using metal discs with porous surfaces (1 microm) and templates at the third minute. Shear stability of specimens was measured in a material testing machine. The ANOVA test was used for comparison between the mean shear results of each group. Results showed that mean shear stress to failure values were 12.28+/-3.35 MPa for the control group, 11.72+/-3.09 MPa for the t-800 group, 13.25+/-2.36 MPa for the t-1,600 group and 13.09+/-2.58 MPa for the g-500 group. No statistically significant differences were found between results of the groups. Results of the study have proven that addition of 1,600 mg of teicoplanin or 500 mg gentamycin in 40 g of bone cement does not decrease the shear strength at the cement-metal interface significantly on the day of application.

Teicoplanin levels in bone and joint infections: Are standard doses subtherapeutic?

OBJECTIVES

Previously published data suggest that a trough serum teicoplanin level of > or = 20 mg/l is predictive of improved outcomes in serious staphylococcal infection. We investigated how dose regimen and patient characteristics impact on trough teicoplanin levels in patients with musculoskeletal infection, in order to help standardise teicoplanin use.

METHODS

We prospectively collected data for 141 clinically stable adults with bone and joint infection treated as outpatients with teicoplanin. Patients with end stage renal failure were excluded.

RESULTS

The most frequently used teicoplanin dose regimens were 400 mg or 600 mg i.v. once daily. Trough levels were available for 78% of episodes, of which 51% were > or = 20 mg/l. Unsurprisingly, a level of > or = 20 mg/l occurred more often with a dose of 600 mg than with lower doses (p=0.005). There was no significant relationship between teicoplanin level and age, body weight or creatinine clearance, but male gender was associated with lower trough levels than female gender (p=0.03).

CONCLUSIONS

These data suggest that teicoplanin levels of > or = 20 mg/l for bone and joint infection in stable adult patients are best achieved with a daily dose of at least 600 mg.

Bacterial endocarditis treated with intramuscular teicoplanin

Right-sided endocarditis caused by Staphylococcus aureus in parenteral drug abusers is potentially life-threatening, more so in the presence of pulmonary embolisation, and a course of parental antibiotics is required for at least four weeks. A combination of intravenous cloxacillin and aminoglycosides has proven efficacious for more than 90 percent of the patients. Intravenous vancomycin can also be used in cases of penicillin allergy or methicillin-resistant staphylococci. Intravenous teicoplanin, a glycopeptide with a similar antimicrobial profile to vancomycin, has been used with a somewhat lesser degree of success in these cases and is not recommended as first line therapy. We describe a 37-year-old man, a parenteral drug user, who had right-sided endocarditis, where in the absence of other alternatives, teicoplanin had to be administered intramuscularly and not intravenously.

Vascular Graft Infection by Staphylococcus aureus: Efficacy of Cefazolin, Teicoplanin and Vancomycin Prophylaxis Protocols in a Rat Model

OBJECTIVES

Prophylactic efficiencies of cefazolin, teicoplanin and vancomycin in a dacron graft infection model caused by methicillin-susceptible (MSSA) or -resistant Staphylococcus aureus (MRSA) were investigated.

DESIGN

Prospective, randomized, controlled animal study.

MATERIALS AND METHODS

Infections were established subcutaneously in the back of rats by implantation of Dacron prostheses followed by topical inoculation onto grafts of MSSA or MRSA. Experimental groups were as follows: Uncontaminated group (control), MSSA- or MRSA-contaminated and untreated groups, MSSA- or MRSA-contaminated groups treated with cefazolin, teicoplanin or vancomycin by one of three regimens (one day, two days, or three days regimen). Grafts were removed 7 days after the implantation and evaluated by using sonication and quantitative blood agar culture.

RESULTS

Contaminated groups demonstrated graft infections. Cefazolin, teicoplanin and vancomycin profoundly prevented the graft infections in MSSA- or MRSA-contaminated groups. For each antibiotic regimen, the most effective prevention was achieved by the drugs given as three days regimen. For MSSA and MRSA, the order of the effectiveness was as follows: teicoplanin>vancomycin>cefazolin.

CONCLUSION

As a prophylactic agent, teicoplanin seems to be more effective than vancomycin and cefazolin against vascular graft infections caused by MSSA and MRSA in rats.

Effects of controlled perioperative antimicrobial prophylaxis on infectious outcomes in pediatric cardiac surgery

OBJECTIVES

To examine the efficacy of a protocol for the prophylactic use of antimicrobials in pediatric cardiac surgery.

DESIGN

Nonrandomized comparison of two groups of patients studied sequentially.

SETTING

Pediatric intensive care unit of university hospital.

PATIENTS

Infants and children <18 yrs of age who had undergone cardiac surgery.

INTERVENTIONS

Limitation of prophylactic antimicrobials to <48 hrs after operation and, in patients at high risk of methicillin-resistant Staphylococcus aureus, strong recommendation to use glycopeptides.

MEASUREMENTS AND MAIN RESULTS

No intervention was applied in 189 patients (control group) during the first 21 months, whereas the intervention was applied in 185 patients (intervention group) during the next 18 months. In the intervention group, prophylaxis was recommended to be discontinued <48 hrs postoperatively. As a result, antimicrobials were administered for a median of 4 days (range 2-14) in the intervention group, significantly shorter than 7 days (3-35) in controls. This was associated with a trend toward a lower frequency of postoperative infections, including at the surgical site, and with significantly lower costs of antimicrobial therapy and a significantly lower rate of newly acquired nasal colonization with antibiotic-resistant pathogens in the intervention group (8%) than in controls (17%).Since, in the intervention group, glycopeptides were strongly recommended for patients at high risk of methicillin-resistant S. aureus, the frequency of surgical-site infections (0% vs. 18%) and the frequency of all infections (11% vs. 39%) were significantly lower in the intervention group than in the control group.

CONCLUSIONS

Limiting the duration of prophylactic antimicrobials was cost-effective and reduced the risk of acquiring resistant pathogens without increasing the frequency of postoperative infections. The use of glycopeptides in properly selected patients at high risk of methicillin-resistant S. aureus infection can lower the risk of postoperative infections.

Distribution of radioactivity in bone and related structures following administration of [14C]dalbavancin to New Zealand white rabbits

Penetration of dalbavancin into noninfected bone and joint tissues was assessed after an intravenous dose of 20 mg/kg (of body weight) [(14)C]dalbavancin given to rabbits. Drug-derived radioactivity, determined over 14 days by either liquid scintillation counting or autoradiography, remained above the MIC for common gram-positive pathogens that cause bone and joint infections.

[Appropriate usage of antibiotics by therapeutic drug monitoring]

Aminoglycosides are mainly distributed in the extracellular fluid, so when they are given to neonates who have a large amount of extracellular fluid, their distribution is increased. In our data, the volume of distribution (Vd) of Arbekacin in the neonates was twice that of the adults, 0.54 l/kg. Therefore, the dose per weight of aminoglycosides to the neonates should be increased more than to the adults. In the renal function of the neonates, differentiation of the nephron is completed within 36 weeks after conception, but it is functionally immature. In our data, renal drug excretion increased rapidly in the post-conceptional ages (PCAs) of 34-35 weeks. Consequently, we based the Arbekacin administration schedule for the neonates on the PCAs. There is excellent correlation between serum level of vancomicin (VCM) and dose x serum creatinine (Scr)/weight in the haemodialysis patients, suggesting that we can use weight and Scr to set the VCM administration schedule for these patients. We also established on administration schedule of Teicoplanin for the haemodialysis patients. In this article, we present the TDM analysis result of the antibiotics in our hospital.

Review of dalbavancin, a novel semisynthetic lipoglycopeptide

Dalbavancin is a semisynthetic lipoglycopeptide that is derived from teicoplanin with an extended half-life that enables once-weekly dosing. It has potent in vitro activity against most gram-positive organisms, with lower minimum inhibitory concentration values than vancomycin and other investigational lipoglycopeptides. Dalbavancin is active against multi-drug-resistant pathogens such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, except for strains exhibiting vanA resistance. Several Phase II and III trials have established similar efficacy and safety of dalbavancin with comparator agents in the treatment of complicated skin and skin structure infections and in catheter-related bloodstream infections. Dalbavancin may serve as an appealing alternative agent in the treatment of gram-positive infections, especially with its convenient once-weekly regimen.

Usefulness of teicoplanin for preventing methicillin-resistant Staphylococcus aureus infections in orthopedic surgery

In order to gather more data on the use of teicoplanin for reducing MRSA infections in high-risk populations, the present study was conducted. At a hospital in Barcelona, Spain, there was a high prevalence of MRSA infections among patients who underwent surgery for femoral neck fracture during the first 5 months of 2002 (period A) when cefuroxime was the antibiotic prophylaxis. During the following 12 months (period B) 600 mg of teicoplanin was added to cefuroxime. The rates of overall and MRSA infection during period A were 5.07 and 2.73%, respectively. Pulsed-field gel electrophoresis demonstrated there was no clonal relationship among MRSA strains. No nasal carriers of MRSA were detected among health workers. During period B the rates of overall and MRSA infection were 2.36 and 0.19%, respectively. Both rates were statistically significantly lower than those in period A (p<0.05). These results suggest teicoplanin may be useful in patients undergoing orthopedic surgery when the prevalence of MRSA is high.

Quantitative determination of individual teicoplanin components in human plasma and cerebrospinal fluid by high-performance liquid chromatography with electrochemical detection

We have developed a simple, rapid and highly sensitive method for determining a plasma or cerebrospinal fluid (CSF) concentrations of individual teicoplanin components using reversed-phase high-performance liquid chromatography followed by electrochemical detection. A linear relationship was observed between concentrations and peak heights for the teicoplanin concentration range of 0.025-10microg/mL. The correlation coefficients of all standard curves were greater than or equal to 0.999. The limit of detection for the major component of teicoplanin was 1.0ng/mL (signal/noise ratio >3). Daily fluctuations of standard curves (n=5) were small, with coefficients of variation of 3.3%. The intra-assay precision was 5.9% (n=5). Inter-assay precision ranged from 2.6 to 6.8%. The method described here is suitable for clinical monitoring of teicoplanin levels in plasma or CSF level and for use in studies involving pharmacokinetics of individual teicoplanin component.

Bactericidal activity of daptomycin, vancomycin, teicoplanin and linezolid against Staphylococcus aureus, Enterococcus faecalis and Enterococcus faecium using human peak free serum drug concentrations

The bactericidal activities of daptomycin, vancomycin, teicoplanin and linezolid at human peak free serum concentrations (C(max,free)) were determined against Staphylococcus aureus (one methicillin-susceptible and two methicillin-resistant strains), Enterococcus faecalis and Enterococcus faecium (one vancomycin-susceptible and one vancomycin-resistant strain of each). Daptomycin was rapidly bactericidal against 7/7 strains at C(max,free) of 22.0 mg/L (corresponding to 63% protein binding) and against 3/7 strains at 4.8 mg/L (corresponding to 92% protein binding). Vancomycin (18.0 mg/L) was bactericidal against only two strains. Both teicoplanin (4.5 mg/L) and linezolid (10.4 mg/L) were consistently bacteriostatic. Daptomycin is a useful option for the treatment of Gram-positive infections owing to its strong bactericidal activity.

[Therapeutic perspectives of linezolid in the management of infections due to multiresistant Gram-positive pathogens]

Multi-antibiotic resistant Gram-positive cocci represent emerging pathogens especially in the setting of the immunocompromised, hospitalized patients, in particular when surgery, invasive procedures, or prosthetic implants are of concern, patients are admitted in intensive care units, or underlying chronic disorders and immunodeficiency are of concern, and broad-spectrum antibiotics and/or immunosuppressive drugs are widely administered. The spectrum of available antimicrobial compounds for an effective management of these relevant infections is significantly impaired in selection and clinical efficacy by the emerging and spread of methicillin-resistant and more recently glycopeptide-resistant Gram-positive microbial strains linezolid, together with the recently licensed quinupristin-dalfopristin, daptomycin and tigecycline, followed by a number of glycopeptides, fluoroquinolones, and other experimental compounds represent an effective response to these concerns, due to their innovative mechanisms of action, their maintained or enhanced activity against multiresistant pathogens, their effective pharmacokinetic/pharmacodynamic properties, their frequent possibility of synergistic activity with other compounds effective against Gram-positive pathogens, and a diffuse potential for a safe and easy administration, also when compromised patients are of concern. The main problems related to the epidemiological and clinical features of multiresistant Gram-positive infection, the potential clinical indications of all recently available compounds compared with the standard of treatment of resistant Gram-positive infections, and updated data on efficacy and tolerability of linezolid have to be clarified.

Antibiotic-containing collagen for the treatment of bone defects

Recent studies have explored the use of biodegradable implants that incorporate antibiotics for the treatment of bone infections. In this study, a biodegradable composite containing bovine collagen and teicoplanin (Targobone) was used for the treatment of mandibular nonunion defects. Patients with mandibular nonunion defects subsequent to osteosynthesis were treated with Targobone (n = 9) or with autologous bone grafts (n = 12). Clinical and radiological evaluations were performed preoperatively, immediately postoperatively, and 4 and 24 weeks postoperatively. Bone regeneration was defined relative to the original defect area in the panoramic radiograph by using image analysis software. In the Targobone group, the defect area decreased to 78% (SD +/- 21.8%) of the preoperative area within 4 weeks and to 21% (SD +/- 9.7%) of the preoperative area within 24 weeks. In the autologous bone graft group, the defect area decreased to 69% (SD +/- 32.4%) of the preoperative area within 4 weeks and to 4.7% (SD +/- 5.6%) of the preoperative area within 24 weeks. Thus, Targobone is a promising option for the treatment of bone defects.

Intracerebral CSF collection mimicking cerebral abscess in a patient suffering from cryptococcal meningitis

We report a case of a large intracerebral CSF collection formed along the course of the catheter of an ommaya-type reservoir (Medtronic 12 mm), implanted in a patient suffered from cryptococcal meningitis in the frame of CLL. This collection was at first diagnosed as intracerebral abscess but emergency craniotomy proves clear CSF collection with no signs of infection. We describe the case and we discuss the issue of CSF pressure pathophysiology and changes in flow dynamics, to patients with cryptococcal meningitis.

Efficacy of daptomycin in the treatment of experimental endocarditis due to susceptible and multidrug-resistant enterococci

OBJECTIVES

Daptomycin was tested in vitro and in rats with experimental endocarditis against the ampicillin-susceptible and vancomycin-susceptible Enterococcus faecalis JH2-2, the vancomycin-resistant (VanA type) mutant of strain JH2-2 (strain JH2-2/pIP819), and the ampicillin-resistant and vancomycin-resistant (VanB type) Enterococcus faecium D366.

METHODS

Rats with catheter-induced aortic vegetations were treated with doses simulating intravenously kinetics in humans of daptomycin (6 mg/kg every 24 h), amoxicillin (2 g every 6 h), vancomycin (1 g every 12 h) or teicoplanin (12 mg/kg every 12 h). Treatment was started 16 h post-inoculation and continued for 2 days.

RESULTS

MICs of daptomycin were 1, 1 and 2 mg/L, respectively, for strains JH2-2, JH2-2/pIP819 and D366. In time-kill studies, daptomycin showed rapid (within 2 h) bactericidal activity against all strains. Daptomycin was highly bound to rat serum proteins (89%). In the presence of 50% rat serum, simulating free concentrations, daptomycin killing was maintained but delayed (6-24 h). In vivo, daptomycin treatment resulted in 10 of 12 (83%), 9 of 11 (82%) and 11 of 12 (91%) culture-negative vegetations in rats infected with strains JH2-2, JH2-2/pIP819 and D366, respectively (P < 0.001 compared to controls). Daptomycin efficacy was comparable to that of amoxicillin and vancomycin for susceptible isolates. Daptomycin, however, was significantly (P < 0.05) more effective than teicoplanin against the glycopeptide-susceptible strain JH2-2 and superior to all comparators against resistant isolates.

CONCLUSIONS

These results support the use of the newly proposed daptomycin dose of 6 mg/kg every 24 h for treatment of enterococcal infections in humans.

Restricted use of glycopeptides in paediatric cancer patients with fever and neutropenia

Until now, studies confirming the safety of glycopeptide restriction in the empirical treatment of prolonged fever and neutropenia included only nine children. In an open-label observational study, the use of teicoplanin in paediatric oncology patients was investigated. A period of unrestricted use (2001-2003) was compared with a second period (2004) following implementation of a restrictive treatment guideline. Empirical first-line treatment consisted of piperacillin/tazobactam; in 2004, fosfomycin was added after 72 h as the second-line combination instead of teicoplanin. In total, 213 episodes (n=163 in 2001-2003; n=50 in 2004) managed with teicoplanin or fosfomycin (only 2004) were eligible. Empirical treatment of fever of unknown origin with teicoplanin was reduced by 97%. In 2004, the mean length of stay was 0.4 days shorter, no infection-related death occurred and no vancomycin-resistant enterococci were detected. Restriction of empirical glycopeptides is safe in paediatric cancer patients after first-line treatment with piperacillin/tazobactam. Fosfomycin appears to offer a feasible and cost-saving alternative in second-line combination therapy.