Promoting prudent use of antibiotics: the experience from a multifaceted regional campaign in Greece

Background

Antibiotic resistance, a major public health problem, has been linked to antibiotic consumption. In Greece both consumption and resistance rates are among the highest in Europe. A multifaceted campaign targeting both physicians and parents of school children was implemented for the first time in order to educate the public and update doctors, aiming to promote judicious use of antibiotics and hopefully decrease its consumption.

Methods

The programme consisted of a public education campaign and academic detailing of primary care physicians in the district of Corinth in Peloponnese. The experience and perceptions of parents were recorded in the meetings in the form of course evaluation and assessment, anonymous questionnaires. The use of Rapid Antigen Detection Test (RADT) for streptococcal pharyngitis by primary care physicians was also assessed by use of anonymous questionnaires. Antibiotic consumption was compared before and after the programme between the district of Corinth and the other districts of Peloponnese, as well as at a national level.

Results

Antibiotic consumption remained unaltered at 26 Defined daily doses per 1000 Inhabitants per Day (DID) in accordance with the trend in other regions and at a national level. However, the utilization of Amoxycillin and Penicillin was increased by 34.3%, while the use of other antimicrobial classes including macrolides, cephalosporins and fluoroquinolones decreased by 6.4-21.9%. The use of RADT did not lead to a significantly decreased antimicrobial consumption.

Conclusions

A multifaceted educational programme targeting both the general public and primary care physicians was associated with rationalization in the choice of antimicrobial. A reduction in the total antimicrobial consumption was not achieved.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2458-14-866) contains supplementary material, which is available to authorized users.

Impact of a hospital-wide antibiotic restriction policy program on the resistance rates of nosocomial Gram-negative bacteria

BACKGROUND

To evaluate the impact of an antibiotic restriction policy on antibiotic consumption and Gram-negative resistance rates, in an environment of antibiotic overconsumption and increasing resistance rates for nosocomial pathogens.

METHODS

The study was a 'before and after' trial of 18-month duration; the antibiotic restriction policy program was implemented in 1998-2000 and was based on a government program addressed by the Ministry of Health to public hospitals on a national basis. This included prescribing of all newer antibiotics on an order form, auditing of the order forms and consultation with infectious diseases (ID) specialists, dispensing of treatment and prophylaxis guidelines, feedback, and face-to-face education. Antibiotic consumption and Gram-negative resistance rates were recorded before and after the intervention.

RESULTS

Despite the addition of a new 40-bed ID department in the hospital during the 'after' period, the consumption of restricted antibiotics was significantly reduced by 42% (and their cost by 31%). Gram-negative resistance rates for Pseudomonas, Klebsiella, and Enterobacter, serving as index microorganisms for Gram-negative nosocomial pathogens, were significantly reduced during the 'after' period, even against antibiotics for which there was an increase in consumption.

CONCLUSIONS

Multidisciplinary restriction programs can reduce antibiotic consumption and Gram-negative resistance rates in the hospital setting.

Prevalence of 16S rRNA methylase genes in Enterobacteriaceae isolates from a Greek university hospital

16S ribosomal RNA methylase-mediated high-level resistance to 4-,6-aminoglycosides has been reported in clinical isolates of gram-negative bacilli from several countries. Three of 1534 (0.2%) isolates of Klebsiella pneumoniae and three of 734 (0.4%) Proteus mirabilis isolates from a university hospital in Athens, Greece, were positive for rmtB and highly resistant to all aminoglycosides tested (MICs ≥256 mg/L). Two of the K. pneumoniae rmtB-bearing isolates, were KPC-2 and OXA-10 producers and the third was a DHA-1 producer. One of the P. mirabilis isolates was a VIM-1 and OXA-10 producer and one was an OXA-10 producer. All rmtB-harbouring isolates were clonally unrelated. None of the E. coli (n = 1398) and Enterobacter spp. (n = 414) isolates were positive for armA, rmtA, rmtB, rmtC or rmtD.

Ampicillin/sulbactam versus cefuroxime as antimicrobial prophylaxis for cesarean delivery: a randomized study

BACKGROUND

The efficacy and safety of a single dose of ampicillin/sulbactam compared to a single dose of cefuroxime at cord clamp for prevention of post-cesarean infectious morbidity has not been assessed.

METHODS

Women scheduled for cesarean delivery were randomized to receive a single dose of either 3 g of ampicillin-sulbactam or 1.5 g of cefuroxime intravenously, after umbilical cord clamping. An evaluation for development of postoperative infections and risk factor analysis was performed.

RESULTS

One hundred and seventy-six patients (median age 28 yrs, IQR: 24-32) were enrolled in the study during the period July 2004-July 2005. Eighty-five (48.3%) received cefuroxime prophylaxis and 91 (51.7%) ampicillin/sulbactam. Postoperative infection developed in 5 of 86 (5.9%) patients that received cefuroxime compared to 8 of 91 (8.8%) patients that received ampicillin/sulbactam (p=0.6). In univariate analyses 6 or more vaginal examinations prior to the operation (p=0.004), membrane rupture for more than 6 hours (p=0.08) and blood loss greater than 500 ml (p=0.018) were associated with developing a postoperative surgical site infection (SSI). In logistic regression having 6 or more vaginal examinations was the most significant risk factor for a postoperative SSI (OR 6.8, 95% CI: 1.4-33.4, p=0.019). Regular prenatal follow-up was associated with a protective effect (OR 0.04, 95% CI: 0.005-0.36, p=0.004).

CONCLUSIONS

Ampicillin/sulbactam was as safe and effective as cefuroxime when administered for the prevention of infections following cesarean delivery.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT01138852.

Early alterations of the innate and adaptive immune statuses in sepsis according to the type of underlying infection

Introduction

Although major changes of the immune system have been described in sepsis, it has never been studied whether these may differ in relation to the type of underlying infection or not. This was studied for the first time.

Methods

The statuses of the innate and adaptive immune systems were prospectively compared in 505 patients. Whole blood was sampled within less than 24 hours of advent of sepsis; white blood cells were stained with monoclonal antibodies and analyzed though a flow cytometer.

Results

Expression of HLA-DR was significantly decreased among patients with severe sepsis/shock due to acute pyelonephritis and intraabdominal infections compared with sepsis. The rate of apoptosis of natural killer (NK) cells differed significantly among patients with severe sepsis/shock due to ventilator-associated pneumonia (VAP) and hospital-acquired pneumonia (HAP) compared with sepsis. The rate of apoptosis of NKT cells differed significantly among patients with severe sepsis/shock due to acute pyelonephritis, primary bacteremia and VAP/HAP compared with sepsis. Regarding adaptive immunity, absolute counts of CD4-lymphocytes were significantly decreased among patients with severe sepsis/shock due to community-acquired pneumonia (CAP) and intraabdominal infections compared with sepsis. Absolute counts of B-lymphocytes were significantly decreased among patients with severe sepsis/shock due to CAP compared with sepsis.

Conclusions

Major differences of the early statuses of the innate and adaptive immune systems exist between sepsis and severe sepsis/shock in relation to the underlying type of infection. These results may have a major impact on therapeutics.

An outbreak of infection due to beta-Lactamase Klebsiella pneumoniae Carbapenemase 2-producing K. pneumoniae in a Greek University Hospital: molecular characterization, epidemiology, and outcomes

BACKGROUND

We describe the emergence and spread of Klebsiella pneumoniae carbapenemase 2 (KPC-2)-producing K. pneumoniae at a Greek University hospital.

METHODS

Isolates with a carbapenem minimum inhibitory concentration >1 microg/mL and a negative EDTA-imipenem disk synergy test result were submitted to boronic acid disk test and to polymerase chain reaction (PCR) for KPC gene and sequencing. Records from patients who had KPC-2-producing K. pneumoniae isolated were retrospectively reviewed. Clinical isolates were submitted to molecular typing using pulsed-field gel electrophoresis, and the beta-lactamase content was studied using isoelectric focusing and PCR.

RESULTS

From January 2007 through December 2008, 50 patients (34 in the intensive care unit [ICU]) were colonized (n = 32) or infected (n = 18) by KPC-2-producing K. pneumoniae. Increasing prevalence of KPC-2-producing K. pneumoniae coincided with decreasing prevalence of metallo-beta lactamase-producing isolates in our ICU. Multidrug resistance characterized the studied isolates, with colistin, gentamicin, and fosfomycin being the most active agents. Besides KPC-2, clinical isolates encoded TEM-1-like, SHV-11, SHV-12, CTX-M-15, and LEN-19 enzymes. Four different clonal types were detected; the predominant one comprised 41 single patient isolates (82%). Sporadic multiclonal cases of KPC-2-producing K. pneumoniae infection were identified from September 2007 through May 2008. The outbreak strain was introduced in February 2008 and disseminated rapidly by cross-transmission; 38 patients (76%) were identified after August 2008. Fourteen cases of bacteremia, 2 surgical site infections, 2 lower respiratory tract infections (1 bacteremic), and 1 urinary tract infection were identified. Most patients received a colistin-containing combination treatment. Crude mortality was 58.8% among ICU patients and 37.5% among non-ICU patients, but attributable mortality was 22.2% and 33.3%, respectively.

CONCLUSIONS

The emergence of KPC-2-producing K. pneumoniae in Greek hospitals creates an important challenge for clinicians and hospital epidemiologists, because it is added to the already high burden of antimicrobial resistance.

Dispensing of antibiotics without prescription in Greece, 2008: another link in the antibiotic resistance chain

Antibiotic resistance has been associated with the use of antibiotics. The dispensing of antimicrobials without prescription is a potential source of inappropriate antibiotic use. In our study, antibiotics were requested without prescription from pharmacies in the metropolitan area of Athens in Greece in 2008. Twenty-one collaborators visited 174 pharmacies and asked for either amoxicillin/clavulanate acid or ciprofloxacin without providing a prescription or any other justification for the request. In Greece additional restrictions for fluoroquinolone prescriptions were implemented in 2003 after which a separate specific prescription form needs to be filled in by the prescriber, justifying the choice of any fluoroquinolone. Amoxicillin/clavulanate acid was dispensed in all cases. Furthermore, despite the regulation restricting the prescription of ciprofloxacin, this drug was dispensed by 53% of the pharmacies. It appears that the implementation of measures to restrict the use of certain antibiotics (e.g. ciprofloxacin that was studied in our case) was effective in reducing, although not eliminating, inappropriate dispensing. Overall, dispensing of antimicrobials without prescription is a widespread practice in the studied area and is contributing to the overuse of antibiotics.

Dispensing of antibiotics without prescription in Greece, 2008: another link in the antibiotic resistance chain

Antibiotic resistance has been associated with the use of antibiotics. The dispensing of antimicrobials without prescription is a potential source of inappropriate antibiotic use. In our study, antibiotics were requested without prescription from pharmacies in the metropolitan area of Athens in Greece in 2008. Twenty-one collaborators visited 174 pharmacies and asked for either amoxicillin/clavulanate acid or ciprofloxacin without providing a prescription or any other justification for the request. In Greece additional restrictions for fluoroquinolone prescriptions were implemented in 2003 after which a separate specific prescription form needs to be filled in by the prescriber, justifying the choice of any fluoroquinolone. Amoxicillin/clavulanate acid was dispensed in all cases. Furthermore, despite the regulation restricting the prescription of ciprofloxacin, this drug was dispensed by 53% of the pharmacies. It appears that the implementation of measures to restrict the use of certain antibiotics (e.g. ciprofloxacin that was studied in our case) was effective in reducing, although not eliminating, inappropriate dispensing. Overall, dispensing of antimicrobials without prescription is a widespread practice in the studied area and is contributing to the overuse of antibiotics.

In vitro elution of moxifloxacin from cancellous bone allografts

The characteristics of cancellous bone allografts as carriers of moxifloxacin are described. Particles of cancellous bone were compressed into a wire-mesh cylinder and impregnated into a solution of moxifloxacin for different time periods. Five replicas were impregnated for 1 h; another five for 24 h; and another five for 48 h. Impregnated allografts were then transferred into vials containing 5 ml of Mueller-Hinton broth and incubated at 37 degrees C. Broth was replaced daily. Concentrations of moxifloxacin in broth were determined after analysis by an high performance liquid chromatography system. Moxifloxacin was eluted at very high concentrations within the first days. Concentrations remained above 100 microg/ml until day 8 and above 40 microg/ml until day 20. It is concluded that cancellous bone allografts may allow the adequate in vitro elution of moxifloxacin. The latter results support their application in experimental models of osteomyelitis.

Effect of the novel influenza A (H1N1) virus in the human immune system

Background

The pandemic by the novel H1N1 virus has created the need to study any probable effects of that infection in the immune system of the host.

Methodology/Principal Findings

Blood was sampled within the first two days of the presentation of signs of infection from 10 healthy volunteers; from 18 cases of flu-like syndrome; and from 31 cases of infection by H1N1 confirmed by reverse RT-PCR. Absolute counts of subtypes of monocytes and of lymphocytes were determined after staining with monoclonal antibodies and analysis by flow cytometry. Peripheral blood mononuclear cells (PBMCs) were isolated from patients and stimulated with various bacterial stimuli. Concentrations of tumour necrosis factor-alpha, interleukin (IL)-1beta, IL-6, IL-18, interferon (FN)-alpha and of IFN-gamma were estimated in supernatants by an enzyme immunoassay. Infection by H1N1 was accompanied by an increase of monocytes. PBMCs of patients evoked strong cytokine production after stimulation with most of bacterial stimuli. Defective cytokine responses were shown in response to stimulation with phytohemagglutin and with heat-killed Streptococcus pneumoniae. Adaptive immune responses of H1N1-infected patients were characterized by decreases of CD4-lymphocytes and of B-lymphocytes and by increase of T-regulatory lymphocytes (Tregs).

Conclusions/Significance

Infection by the H1N1 virus is accompanied by a characteristic impairment of the innate immune responses characterized by defective cytokine responses to S.pneumoniae. Alterations of the adaptive immune responses are predominated by increase of Tregs. These findings signify a predisposition for pneumococcal infections after infection by H1N1 influenza.

Pharmacokinetics of moxifloxacin in patients undergoing continuous ambulatory peritoneal dialysis

OBJECTIVE

To investigate the effect of continuous ambulatory peritoneal dialysis (CAPD) on plasma and peritoneal fluid concentration and pharmacokinetics of moxifloxacin after administration of one 400 mg dose orally to end-stage renal failure patients undergoing CAPD.

PATIENTS AND METHODS

Blood and peritoneal samples were collected from 8 patients at standard time intervals and concentrations of moxifloxacin were estimated by HPLC analysis with fluorometric and ultraviolet detection. Pharmacokinetic parameters were estimated using standard noncompartmental methods.

RESULTS

Median maximum plasma moxifloxacin concentration was 5.86 mg/L at a median time of 1.25 hours. In serum, median area under the concentration-time curve (AUC(0-->inf)) was 157.95 +/- 100.34 mg.hour/L, median t(1/2) 25.00 hours, median clearance 2.54 L/hour, and median distribution volume 94.90 L. Median peritoneal fluid-to-plasma ratio of moxifloxacin ranged between 0.84 and 1.00, denoting adequate penetration and lack of considerable moxifloxacin removal during CAPD. Maximum moxifloxacin concentration/minimum inhibitory concentration (MIC) and AUC(0-->24)/MIC ratios were above the cutoff points that indicate clinical success.

CONCLUSION

A single 400 mg oral dose of moxifloxacin is safe, presents rapid peritoneal fluid penetration, has similar plasma and peritoneal fluid pharmacokinetics, and should therefore be efficacious in the treatment of CAPD-induced peritonitis.

Pharmacokinetics of Moxifloxacin in Patients Undergoing Continuous Ambulatory Peritoneal Dialysis

Objective

To investigate the effect of continuous ambulatory peritoneal dialysis (CAPD) on plasma and peritoneal fluid concentration and pharmacokinetics of moxifloxacin after administration of one 400 mg dose orally to end-stage renal failure patients undergoing CAPD.

Patients and Methods

Blood and peritoneal samples were collected from 8 patients at standard time intervals and concentrations of moxifloxacin were estimated by HPLC analysis with fluorometric and ultraviolet detection. Pharmacokinetic parameters were estimated using standard noncompartmental methods.

Results

Median maximum plasma moxifloxacin concentration was 5.86 mg/L at a median time of 1.25 hours. In serum, median area under the concentration–time curve (AUC0→inf) was 157.95 ± 100.34 mg·hour/L, median t½ 25.00 hours, median clearance 2.54 L/hour, and median distribution volume 94.90 L. Median peritoneal fluid-to-plasma ratio of moxifloxacin ranged between 0.84 and 1.00, denoting adequate penetration and lack of considerable moxifloxacin removal during CAPD. Maximum moxifloxacin concentration/minimum inhibitory concentration (MIC) and AUC0→24/MIC ratios were above the cutoff points that indicate clinical success.

Conclusion

A single 400 mg oral dose of moxifloxacin is safe, presents rapid peritoneal fluid penetration, has similar plasma and peritoneal fluid pharmacokinetics, and should therefore be efficacious in the treatment of CAPD-induced peritonitis.

In vitro release of fusidic acid and teicoplanin from cancellous bone allografts

The characteristics of cancellous bone allografts as carriers of fusidic acid and teicoplanin are described. Particles of cancellous bone were compressed into a wiremesh cylinder; five replicas were impregnated for one hour into fusidic acid; and another five for one hour into teicoplanin. Elution was estimated daily. Concentrations of fusidic acid and teicoplanin were determined by a microbiological assay. Both antibiotics were eluted at very high concentrations within the first days. Allografts impregnated in fusidic acid provided concentrations above 20 microg/ml for 20 days. Eluted teicoplanin after day 4 was below 10 microg/ml. It is concluded that cancellous bone allografts may allow adequate in vitro elution of fusidic acid but not of teicoplanin. The latter results support their application in experimental models of osteomyelitis.

Does a bed rail system of alcohol-based handrub antiseptic improve compliance of health care workers with hand hygiene? Results from a pilot study

BACKGROUND

Hand hygiene is the cornerstone of prevention of nosocomial infections and a challenge for infection-control teams.

METHODS

Bed-rail dispensers of alcohol-based hand rub antiseptic (AHRA) were first initiated only in department A (period I), followed by department B (period II). Opportunities for hand hygiene (OHH) were recorded during periods I, II, and III (post-trial follow-up). Only application of AHRA before and after contacting each patient was considered as appropriate. Comparative evaluation between periods I and II, as well as II and III, was performed. Predictors of AHRA compliance were also assessed by regression analysis.

RESULTS

HCWs' compliance was improved after the initiation of the bed-rail approach in department B (51.5%, vs 36.4% P = .005). In department A, where this system already existed, no changes were observed. The bed-rail AHRA system (P = .007 [OR 1.8(1.2-3.0)]) and nurses (P < .0001[OR 5.6 (3.1-9.9)]) were predictors of hand hygiene in department B. HCWs' compliance declined in department B (26.5% vs 51.5%, P < .0001) and department A (27.5% vs 35.9%, P = .1) during period III.

CONCLUSIONS

The bed-rail approach initially improved HCWs' compliance with AHRA but did not radically influence behavior in internal medicine settings. Multidisciplinary strategies are required to establish hand hygiene recommendations.

Treatment of experimental osteomyelitis caused by methicillin-resistant Staphylococcus aureus with a synthetic carrier of calcium sulphate (Stimulan) releasing moxifloxacin

The objectives of this study were to assess the efficacy of a synthetic semihydrate form of calcium sulphate (Stimulan) in experimental bone infection caused by methicillin-resistant Staphylococcus aureus (MRSA). Osteomyelitis was induced after inoculation of the test pathogen in the left tibia of 72 New Zealand rabbits assigned to the following groups: 18 control rabbits (Group A); 18 rabbits with Stimulan implanted (Group B); and 36 rabbits with moxifloxacin-impregnated Stimulan implanted (Group C). Rabbits were sacrificed at weekly intervals and cancellous bone was harvested for histopathology and for estimation of bacterial growth and concentrations of moxifloxacin. Bacterial growth from cancellous bone of Group C was significantly lower than the respective growth of Groups A and B on all days of sacrifice. The main histological finding of animals in all three groups was a moderate to intense inflammatory reaction accompanied by fibrosis. The degree of fibrosis was higher in Group C compared with both other groups. Infiltration by giant cells was also observed, which was greater in Group C on Day 42. Antibiotic levels in bone were higher for bone samples closer to the site of implantation. In conclusion, Stimulan admixed with 10% moxifloxacin was very effective in achieving complete eradication of the causative pathogen in experimental osteomyelitis caused by MRSA.

Treatment of experimental osteomyelitis by methicillin resistant Staphylococcus aureus with bone cement system releasing grepafloxacin

The authors examined the effectiveness of the local anti-microbial treatment on methicillin resistant Staphylococcus aureus (MRSA) experimental osteomyelitis. Thirty-six rabbits with chronic MRSA osteomyelitis of the right femur were treated with local grepafloxacin delivery system prepared by a mixture of acrylic bone cement (polymethyl methacrylate, PMMA) plus 4% grepafloxacin. Osteomyelitis was induced by inoculating MRSA (100 microl of cultured bacteria; 10(7)) and the local insertion of a needle, serving as a foreign body, at the upper third of the femur. The course of the infection was followed by clinical, radiographic and microbiological examination. In the third week, all animals were re-operated, needles were removed, and antibiotic containing acrylic cement was implanted. Thereafter, one control and five treated animals were sacrificed per week, within 6 weeks. Osteomyelitis was found in all rabbits. In vitro grepafloxacin levels remained high throughout the 6 weeks of the experiment. Histologically tissue reaction against the cement was not observed. Osteomyelitis lesions and bone structure were progressively repaired after cement implantation. Biomechanical analysis showed no significant influence on the mechanical properties of acrylic cement due to grepafloxacin. The above mixture could prove to be an important supplementary method for the treatment of bone infections. Such a system could replace the use of gentamycin PMMA beads in the treatment of patients with chronic osteomyelitis due to MRSA. Furthermore, the proposed method could be used as a spacer after removal septic loosened prostheses in combination with systemic administration of antibiotics.

Kinetics of angiopoietin-2 in serum of multi-trauma patients: correlation with patient severity

BACKGROUND

Angiopoietin-2 (Ang-2) is considered a proinflammatory mediator promoting vascular leakage. Its participation in the inflammatory process following multiple injuries was investigated.

METHODS

Blood was sampled on consecutive days from 54 patients with multiple injuries and six healthy volunteers. Ang-2 was estimated in serum by an enzyme immunoassay.

RESULTS

From the enrolled patients, 10 did not develop any complication; 17 developed systemic inflammatory response syndrome (SIRS); 16 developed sepsis and 11 severe sepsis. Among those who did not develop any complication, all survived. Ang-2 was increased on days 4 and 7 of follow-up in patients with SIRS. Ang-2 was highly increased upon advent of sepsis and of severe sepsis. Patients with serum levels below 15,200 pg/ml survived longer compared to those with levels above 15,200 pg/ml (p=0.015). OR for death with serum Ang-2 above 15,200 pg/ml was 4.00 (p=0.037).

CONCLUSIONS

Serum levels of Ang-2 in multi-trauma patients are increased upon advent of septic complications and they are connected with bad prognosis. Its exact role in the process of multiple trauma remains to be defined.

Pharmacokinetics of intravenously administered moxifloxacin in eye compartments: an experimental study

The purpose of this study was to evaluate the pharmacokinetics of intravenously administered moxifloxacin, a fourth-generation fluoroquinolone, in different parts of the non-inflamed eye. Moxifloxacin was administered intravenously at a dose of 20mg/kg moxifloxacin over 30min. Sampling of peripheral blood, aqueous humour and vitreous was performed at standard time intervals post infusion once in each animal. Moxifloxacin levels were estimated by high-performance liquid chromatography with fluorescence detection. Mean serum concentrations were 3.43, 2.74, 1.48 and 1.12microg/mL at 0.5, 3, 6 and 24h after the end of drug infusion, respectively. Respective concentrations in aqueous humour were 2.44, 2.03, 1.30 and 1.09microg/mL and in vitreous body they were 1.68, 1.87, 1.78 and 1.15microg/mL. It is concluded that systemic administration of moxifloxacin in rabbits was accompanied by efficient penetration into both the aqueous humour and the vitreous body at concentrations well above the minimum inhibitory concentration for most causative pathogens of endophthalmitis. Further research is mandatory to clarify the clinical significance of these findings.

The impact on community acquired pneumonia empirical therapy of diagnostic bronchoscopic techniques

The aim of the present study was to examine the modification of initial empirical treatment based on the microbiological results of bronchoscopic techniques after comparing the diagnostic yield of protected specimen brush (PSB) and bronchoalveolar lavage (BAL) in the immunocompetent patient with community acquired pneumonia (CAP) with results obtained from conventional sputum cultures. 88 patients with presumptive diagnosis of CAP necessitating hospitalization were prospectively studied. Fibreoptic bronchoscopy with quantitative PSB and BAL cultures for common pathogens, mycobacteria and fungi was performed. Conventional sputum cultures were also obtained. PSB and BAL quantitative cultures added 26.1% and 36.4%, respectively, more microbiological documentation for CAP compared to conventional sputum cultures (p < 0.0001). Gram staining was indicative of the pathogen mostly in cases where Streptococcus pneumoniae was isolated, which was also the most frequently isolated pathogen (19.3%), followed by Haemophilus influenzae (9%). M. tuberculosis was isolated in 6.8% of patients. Modification of treatment ensued in 27.3% of patients because of the application of the cultures of sputum and invasive technique. PSB and BAL added significant information to the aetiological diagnosis of hospitalized immunocompetent patients with CAP.

Efficacy of teicoplanin, administered in two different regimens, in the treatment of experimental endocarditis due to Enterococcus faecalis

Using a rabbit model of endocarditis, we studied the efficacy of teicoplanin against a strain of Enterococcus faecalis resistant to ampicillin. Rabbits were randomly assigned to receive no antibiotics, teicoplanin 12 or 18 mg/kg of body weight every 12h, for 9 days. The effect of treatment on bacterial counts of vegetations and survival of the animals was evaluated at the end of treatment and 10 days thereafter. The two treatment regimens of teicoplanin produced peak serum levels 18.51+/-1.84 and 34.66+/-4.19 microg/ml, and trough levels above 10 x MIC of teicoplanin for the infecting organism. Both regimens resulted in significant bacterial reduction in the vegetations as compared to the control group (p<0.001). The drug prevented relapse of the infection 10 days after discontinuation of treatment. By increasing the teicoplanin dosage no additional therapeutic benefit was observed in terms of bacterial killing, sterilization of the vegetations, and survival of the animals, although the higher doses gave numerically superior results. These findings may have meaning for the optimum use of teicoplanin in the treatment of enterococcal endocarditis.

Acinetobacter baumannii: a universal threat to public health?

Acinetobacter spp. are non-fermentative, strictly aerobic, Gram-negative microorganisms with a confusing taxonomic history. The Acinetobacter baumannii-Acinetobacter calcoaceticus complex is the species most commonly isolated from clinical specimens. It is ubiquitous in nature and has been found as part of the normal skin, throat and rectal flora as well as in food and body lice. It colonises patients in Intensive Care Units and contaminates inanimate hospital surfaces and devices as well as wounds, including war injuries. Although a frequent coloniser, Acinetobacter can be the cause of severe and sometimes lethal infections, mostly of nosocomial origin, predominantly ventilator-associated pneumonia. Bacteraemic infections are rare but may evolve to septic shock. Acinetobacter also emerges as a cause of nosocomial outbreaks and is characterised by increasing antimicrobial multiresistance. Antibiotic use, especially carbapenems and third-generation cephalosporins, is recognised as the most important risk factor for multiresistance. Described resistance mechanisms include hydrolysis by beta-lactamases, alterations in outer membrane proteins and penicillin-binding proteins, and increased activity of efflux pumps. Today, Acinetobacter resistant to carbapenems, aminoglycosides and fluoroquinolones presents a challenge to the clinician. However, sulbactam, tigecycline and colistin represent the current therapeutic approaches, which are associated with satisfactory efficacy.

In vitro synergism of beta-lactams with ciprofloxacin and moxifloxacin against genetically distinct multidrug-resistant isolates of Pseudomonas aeruginosa

In vitro combinations of beta-lactams with fluoroquinolones against multidrug-resistant (MDR) Pseudomonas aeruginosa were tested. From a total of 200 isolates, 24 genetically distinct isolates defined by pulsed-field gel electrophoresis (PFGE) were selected. The isolates were exposed over time to imipenem, meropenem and ceftazidime as well as to their combinations with ciprofloxacin and moxifloxacin. All isolates were resistant to all agents tested at concentrations equal to their average serum level. Synergy of any of the tested combinations was found in 10 isolates (41.7%). This was shown after 4h and 6h of exposure accompanied by re-growth after 24h. Not all the tested combinations were active against the same isolates. The combinations of imipenem+ciprofloxacin, ceftazidime+ciprofloxacin and imipenem+moxifloxacin were the most active. When time-kill assays were repeated for the latter isolates at antimicrobial concentrations equal to their maximum serum levels, synergy was prolonged to 24h. The present findings should be interpreted with caution for the management of infections by MDR P. aeruginosa. They underscore the potential interest of reporting synergism between beta-lactams and fluoroquinolones in the nosocomial setting when a MDR isolate emerges.

Pharmacokinetics of moxifloxacin in non-inflamed cerebrospinal fluid of humans: implication for a bactericidal effect

OBJECTIVES

To evaluate the ability of moxifloxacin to penetrate healthy brain barriers.

METHODS

Fifty patients received a single oral dose of 400 mg as an antimicrobial prophylaxis regimen for a short urological procedure under spinal anaesthesia. Serum and cerebrospinal fluid (CSF) were sampled at different time intervals post-drug intake and patients were divided into five groups, as follows: group I: 0.5-1 h; group II: 1-2 h; group III: 2-4 h; group IV: 4-6 h; and group V: 6-8 h. Concentrations of moxifloxacin were estimated after analysis by an HPLC system. Bactericidal activity of CSF samples of groups III and IV was assessed by a microdilution technique against two penicillin-resistant isolates of Streptococcus pneumoniae with MICs of moxifloxacin of 0.19 and 0.125 mg/L, respectively.

RESULTS

Mean CSF concentrations of moxifloxacin of groups I, II, III, IV and V were 0.19, 0.87, 3.00, 4.07 and 1.82 mg/L, respectively. The mean bactericidal activity of CSF of group III was 8 and that of group IV was 4.

CONCLUSIONS

Single oral intake of 400 mg moxifloxacin is accompanied by good penetration through healthy meninges within 2-6 h post-dose and reached adequately high levels in human CSF exerting satisfactory bactericidal activity against penicillin-resistant S. pneumoniae. These results render novel perspectives for a role of moxifloxacin in CNS infections.

Plasma pro- and anti-inflammatory cytokine levels and outcome prediction in unselected critically ill patients

PURPOSE

To determine the inter-relationships between cytokine levels and physiological scores in predicting outcome in unselected, critically ill patients.

METHODS

To this end, 127 patients (96 men), having a mean+/-SD age of 45+/-20 years, with a wide range in admission diagnoses (medical, surgical, and multiple trauma patients) were prospectively investigated. Severity of critical illness and organ dysfunction were graded by acute physiology and chronic health evaluation (APACHE II) and sequential organ failure assessment (SOFA) scores, respectively. Blood samples were drawn on admission in the ICU to determine pro- and anti-inflammatory cytokines, including tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-8, and IL-10. The main outcome measure was 28-day mortality.

RESULTS

Overall, 88 patients survived and 39 patients died. Univariate logistic regression analysis showed that SOFA, APACHE II, IL-8, IL-6, and IL-10 on admission in the ICU were related to mortality. Multiple logistic regression analysis in the entire cohort of critically ill patients revealed that SOFA (OR=1.341, p<0.001) and IL-6 (OR=1.075, p=0.01) constituted independent outcome predictors. receiver operator characteristics curve analysis showed that SOFA, APACHE II, and IL-6 had the highest area under the curve values. IL-6 correlated with APACHE II (r(s)=0.44, p<0.0001) and SOFA (r(s)=0.40, p<0.0001) scores.

CONCLUSIONS

In mixed ICU patients cytokine concentrations on admission in the ICU represent independent outcome predictors in the presence of disease severity scores.

Treatment of stage III-A-1 and III-B-1 periprosthetic knee infection with two-stage exchange arthroplasty and articulating spacer

The incidence of periprosthetic knee infection is generally low, but the economic impact is great. Treatment should take into account the acuteness of the infection, the overall immune/medical status of the patient, and the local factors at the site of the infection. The aim of this study was to evaluate the two-phase exchange arthroplasty with the use of antibiotic-impregnated articulating spacer, as an alternative treatment of chronic periprosthetic knee infection in patients with minimum systemic and no local compromising factors. Staphylococcus aureus was the most common pathogen followed by Staphylococcus epidermidis and Pseudomonas aeruginosa. Twenty-four patients were treated with this regiment. All of them returned to normal everyday activity and no infection recurrence was noted over a 2- to 10-year follow-up. Excellent long-term results can be achieved for patients staged as III-A-1 and III-B-1 according to the Musculoskeletal Infection Society staging system, when treated with the aforementioned protocol and intravenous antibiotics.

Bacteriologic and therapeutic considerations in intra-abdominal surgical infections

The most important factor in the treatment of intra-abdominal infections are early diagnosis and prompt surgical intervention while antibiotics play a secondary role. The goals of surgical procedures should be to stop peritoneal contamination, to debride necrotic tissue, to remove debris and foreign bodies and to drain any pus collection. Antibiotics should be initiated before surgery and they must encompass both colonic aerobes and anaerobes including Bacteroides fragilis group but not necessary Enterococcus sp. Antibacterial agents with pure activity against anaerobes include chloramphenicol, clindamycin and the nitroimidazoles while ampicillin/sulbactam, amoxicillin/clavulanate, ticarcillin/clavulanate, cefoxitin, cefotetan, ceftizoxime imipenem/cilastatin, meropenem and some advanced quinolones like sparfloxacin, represent a single drug to cover both aerobic and anaerobic microflora. Although almost all clinical trials usually result in a 90% efficacy rate, the final outcome is dependant on the stage of the infection (early versus late), sepsis score, underlying diseases and the applied surgical procedures. On the other hand the choice of antibiotic(s) must be influenced by its toxicity, profiles local nosocomial susceptibility patterns, resistance inducing ability and price.

The significance of compliance for the success of antimicrobial prophylaxis in recurrent lower urinary tract infections: the Greek experience

In an attempt to define the most important driver responsible for recurrence of cystitis in women, 181 records were retrospectively analysed among 1010 consecutive references in a tertiary centre for lower urinary tract infections (UTIs). All 181 women had more than three episodes of cystitis per year; 129 were under continuous prophylaxis and 52 were under postcoital prophylaxis. Analysis revealed that the most important factor affecting successful outcome of chemoprophylaxis was the compliance of patients (odds ratio 0.074; P<0.0001). Among women treated for >or=6 months, the most effective regimen was nitrofurantoin, with a success rate of 96.8% compared with 82.8% for trimethoprim/sulphamethoxazole and 72.3% for norfloxacin (P=0.046 between agents). Failure of chemoprophylaxis was observed in 51 women in total; in 26 of them resistance to the administered agent had developed. Results of this retrospective study revealed that the most important driver leading to failure of prophylaxis for recurrent lower UTIs was the lack of compliance of women with their medication. Nitrofurantoin was the most potent among the administered agents.

Management of a multidrug-resistant Pseudomonas aeruginosa infected total knee arthroplasty using colistin. A case report and review of the literature

Multidrug-resistant infections present a serious clinical and therapeutical problem. Colistin is an old-used polymyxin with rather poor pharmacokinetic profile and a remarkable nephrotoxicity. However, the emergence of multidrug-resistant bacteria has recently led to the increased use of colistin as a potentially available therapy. This article presents a 75-year-old diabetic woman with an early onset total knee arthroplasty infection by a multidrug-resistant Pseudomonas aeruginosa bacterial isolate that was managed successfully with surgical removal of the knee prosthesis, antibiotic impregnated cement and intravenous administration of colistin for 6 weeks, and second stage revision knee surgery. Two years later, laboratory and imaging studies showed no evidence of recurrence of infection.

The Value of Chemoprophylaxis Against Enterococcus Species in Elective Cholecystectomy

HYPOTHESIS

Cephalosporins are widely used and considered to be effective as prophylaxis in biliary surgery. Nevertheless, they lack activity against enterococci. We conducted a study to compare the efficacy of ampicillin-sulbactam vs cefuroxime in preventing surgical site infections following elective cholecystectomy.

DESIGN

A prospective randomized controlled trial.

SETTING

A major tertiary care hospital.

PATIENTS

Four hundred eighteen randomized patients (of 549 total), who from July 2002 to August 2004 underwent elective open or laparoscopic cholecystectomy with prospective assessment for development of surgical site infections for 1 month postoperatively.

INTERVENTION

A single intravenous dose of 1.5 g of cefuroxime (group A, n = 207) or 3 g of ampicillin-sulbactam (group B, n = 211) was administered during induction of anesthesia. Bile and gallbladder mucosal cultures were taken intraoperatively from all patients.

MAIN OUTCOME MEASURE

Number of postoperative surgical site infections.

RESULTS

A postoperative surgical site infection was noted in 19 (4.5%) of 418 patients, 18 from group A and 1 from group B (P<.001). In the group that received cefuroxime, 15 (83.3%) of 18 surgical site infections were due to Enterococcus species. Intraoperative bactibilia as well as intraoperative gallbladder rupture were associated with surgical site infections (P<.001).

CONCLUSIONS

A single dose of ampicillin-sulbactam favored better compared with cefuroxime for prevention of postoperative surgical site infections due to Enterococcus species after elective cholecystectomy. Ampicillin-sulbactam may be a better agent for antimicrobial prophylaxis in high-risk patients undergoing elective cholecystectomy, especially in a setting where the incidence of enterococcal infections is higher.

No Effect of Pyridoxine on the Incidence of Myelosuppression during Prolonged Linezolid Treatment

Complications of long-term linezolid administration include anemia and thrombocytopenia. A recent report has suggested that pyridoxine may prevent myelosuppression. Pyridoxine was administered to 24 patients with bone infections who were being treated with linezolid. Thrombocytopenia occurred in 11 patients (45.8%), and anemia occurred in 6 (25%). We concluded that treatment wtih pyridoxine is unlikely to benefit patients who have been receiving linezolid for >2 weeks.

Comparative elution of moxifloxacin from Norian skeletal repair system and acrylic bone cement: an in vitro study

The objective of this study was to evaluate the efficacy of Norian skeletal repair system (SRS), a novel biodegradable and injectable form of calcium phosphate cement with a composition similar to that of cancellous bone, as a carrier for moxifloxacin, which is the most potent quinolone agent against staphylococci and Enterobacteriaceae. Norian SRS was mixed with moxifloxacin at a ratio of ca. 100:3 at room temperature and solidified in the bottom of a cylindrical vial. The same procedure was followed for acrylic bone cement. A total of five vials were prepared per system. Mueller-Hinton broth was placed over the free surface of both systems and the vials were transferred to a 37 degrees C incubator. The broth was replaced daily until visual degradation of both systems. Moxifloxacin was measured in aliquots of broth after passage through a high-performance liquid chromatography system. Optical degradation of both systems occurred after 450 days. Until Day 17, concentrations eluted from both systems were similar. After Day 18 until degradation, concentrations eluted by Norian SRS were statistically higher than those eluted by acrylic bone cement and ranged between 100 mg/L and 800 mg/L. The mean area under the concentration-time curve (AUC) over 450 days of sampling was 241 935.0 mg/L day for Norian SRS and 18 300.0 mg/L day for the acrylic bone cement system (P=0.043). Norian SRS is a novel biodegradable system providing excellent strength and mineralisation to bone. It was shown that this system allows in vitro elution of moxifloxacin at significant concentrations, making it a promising candidate for the therapy of chronic osteomyelitis.

Multidrug resistance to antimicrobials as a predominant factor influencing patient survival

The impact of multidrug resistance to antimicrobials was assessed in a cohort of 243 patients with microbiologically documented infections by a variety of susceptible and multidrug-resistant (MDR) species. Multidrug resistance was defined as resistance to more than two antimicrobial agents of different chemical structure. Cox regression analysis was performed to define differences and the significance of any predisposing factors. Overall survival of patients infected by susceptible isolates was prolonged compared with patients infected by MDR isolates (P=0.013). Mortality rates of infections caused by susceptible and MDR isolates were 4.87% and 16.15%, respectively (P=0.013); the higher mortality rate for MDR isolates was more pronounced for infections by Klebsiella pneumoniae and Pseudomonas aeruginosa. Mean (+/-standard error (S.E.)) survival of patients infected by susceptible and MDR isolates in patients without signs of severe sepsis was 28 days and 27.29+/-0.35 days, respectively (P=not significant). Mean (+/-S.E.) survival of patients with severe sepsis caused by susceptible and MDR isolates was 7.70+/-4.62 days and 10.45+/-2.18 days, respectively (P=0.048). Diabetes mellitus type 2, the presence of severe sepsis and any underlying malignancy were the most important risk factors affecting survival. It is concluded that infections by MDR isolates were accompanied by higher mortality rates and decreased survival compared with infections by susceptible isolates. Diabetes mellitus type 2 and underlying malignancies were significant co-morbid conditions, whereas survival after infection by susceptible isolates was particularly decreased in the event of severe sepsis.

A bioresorbable calcium phosphate delivery system with teicoplanin for treating MRSA osteomyelitis

To assess the effectiveness of calcium phosphate as a delivery system of teicoplanin, methicillin-resistant Staphylococcus aureus osteomyelitis was induced in 36 rabbits. Osteomyelitis was induced by inoculating 10 cfu of methicillin-resistant Staphylococcus aureus isolate into a 2-mm hole at the upper 1/3 of the femur for 3 weeks, when all animals had reoperations, and calcium phosphate cement with 3% teicoplanin was implanted. Animals were divided into six groups of six animals each, sacrificed at Weeks 1, 2, 3, 4, 5, and 6, respectively, after implantation. One rabbit in each group was used as a control. Substantial clinical improvement of the rabbits was observed after implantation, accompanied with sterile cultures of bone after the second week of treatment. Throughout the same period, 10 to 10 cfu/g of methicillin-resistant Staphylococcus aureus isolate was cultured from the control samples. Bacterial eradication signified a considerable decrease of the total histologic scores of osteomyelitis compared with controls, accompanied with newly growing host bone. The calcium phosphate with teicoplanin delivery system seems promising for treatment of bone infection attributable to methicillin-resistant Staphylococcus aureus. In addition, this mixture allows filling of bone defects by new host bone.

Infecton: a 99mTc-ciprofloxacin radiopharmaceutical for the detection of bone infection

OBJECTIVE

To evaluate Infecton scintigraphy, with technetium-99m-radiolabeled ciprofloxacin, as a means to detect bone infection, in comparison with other conventional scintigraphic and radiologic methods.

METHODS

Forty-five patients with known or suspected bone infection underwent 50 scans with Infecton. Almost all were also subjected to a three-phase 99mTc-methylene diphosphonate bone scan and most of them to a 99mTc-human polyclonal immunoglobulin scan as well as to a gallium-67-citrate scan, plus computerized tomography or magnetic resonance imaging or both. Clinical laboratory criteria for the presence of osteomyelitis were based on the definitions of the Centers for Disease Control and Prevention.

RESULTS

Staphylococcus aureus and Pseudomonas aeruginosa were the most frequently isolated pathogens. Based on the CDC clinical laboratory criteria as well as on conventional scan results, Infecton was characterized in 35 studies as 'true positive', in eight as 'true negative', in two as 'false positive', in one as 'false negative', and in four as 'indeterminate'. The sensitivity and specificity of Infecton scintigraphy were found to be 97.2% and 80%, respectively, with positive and negative predictive values of 94.6% and 88.9%.

CONCLUSIONS

It is concluded that Infecton is a very sensitive and quite specific marker of bone infection, but care must be taken in cases of excessive new bone formation and primary bone tumors, where false-positive results may be obtained.

Transferable plasmid mediating resistance to multiple antimicrobial agents in Klebsiella pneumoniae isolates in Greece

OBJECTIVE

To investigate the underlying resistance mechanisms in 10 Klebsiella pneumoniae isolates.

METHODS

Ten K. pneumoniae strains according to distinct bacteriocin typing and REP-PCR, were examined for their plasmid content, their ability to transfer their resistance to aminoglycosides and third-generation cephalosporins, and their production of aminoglycoside-modifying enzymes and beta-lactamases.

RESULTS

Transfer of resistance to the above-mentioned antibiotics as well as to co-trimoxazole and tetracycline in Escherichia coli strain RC 85 at a frequency of 5-106 was achieved for all strains by conjugation. Similar strains harbor a self-transferable multiresistant plasmid (80 kb) with similar EcoRI and HindIII restriction patterns. This plasmid encodes an extended-spectrum beta-lactamase which confers high-level resistance to third-generation cephalosporins and aztreonam. It produces SHV-5 beta-lactamase, as demonstrated by isoelectric focusing and DNA sequencing. Aminoglycoside resistance was co-transferred, and AAC(6')-I, mediating resistance to gentamicin, tobramycin, netilmicin and amikacin, and AAC(3)-I, mediating resistance to gentamicin and sisomycin, were encoded in all isolates and their transconjugants, while APH(3')-I, mediating resistance to kanamycin and neomycin, was encoded in seven strains.

CONCLUSIONS

It appears that a multiresistant transferable plasmid encoding the SHV-5 beta-lactamase, causing unusually high resistance to ceftazidime and aztreonam, and the combination AAC(6')-I + AAC(3)-I of acetylating enzymes causing, also resistance to all clinically available aminoglycosides, is established in K. pneumoniae in Greece.