Intensive care antibiotic consumption and resistance patterns: a cross-correlation analysis.

BACKGROUND: Over recent decades, a dramatic increase in infections caused by multidrug-resistant pathogens has been observed worldwide. The aim of the present study was to investigate the relationship between local resistance bacterial patterns and antibiotic consumption in an intensive care unit in a Romanian university hospital. METHODS: A prospective study was conducted between 1st January 2012 and 31st December 2013. Data covering the consumption of antibacterial drugs and the incidence density for the main resistance phenotypes was collected on a monthly basis, and this data was aggregated quarterly. The relationship between the antibiotic consumption and resistance was investigated using cross-correlation, and four regression models were constructed, using the SPSS version 20.0 (IBM, Chicago, IL) and the R version 3.2.3 packages. RESULTS: During the period studied, the incidence of combined-resistant and carbapenem-resistant P. aeruginosa strains increased significantly [(gradient = 0.78, R2 = 0.707, p = 0.009) (gradient = 0.74, R2 = 0.666, p = 0.013) respectively], mirroring the increase in consumption of ß-lactam antibiotics with ß-lactamase inhibitors (piperacillin/tazobactam) and carbapenems (meropenem) [(gradient = 10.91, R2 = 0.698, p = 0.010) and (gradient = 14.63, R2 = 0.753, p = 0.005) respectively]. The highest cross-correlation coefficients for zero time lags were found between combined-resistant vs. penicillins consumption and carbapenem-resistant P. aeruginosa strains vs. carbapenems consumption (0.876 and 0.928, respectively). The best model describing the relation between combined-resistant P. aeruginosa strains and penicillins consumption during a given quarter incorporates both the consumption and the incidence of combined-resistant strains in the hospital department during the previous quarter (multiple R2 = 0.953, p = 0.017). The best model for explaining the carbapenem resistance of P. aeruginosa strains based on meropenem consumption during a given quarter proved to be the adjusted model which takes into consideration both previous consumption and incidence density of strains during the previous quarter (Multiple R2 = 0.921, p = 0.037). CONCLUSIONS: The cross-correlation coefficients and the fitted regression models provide additional evidence that resistance during the a given quarter depends not only on the consumption of antibacterial chemotherapeutic drugs in both that quarter and the previous one, but also on the incidence of resistant strains circulating during the previous quarter.

Antimicrobial consumption, costs and resistance patterns: a two year prospective study in a Romanian intensive care unit.

BACKGROUND: Due to the vulnerable nature of its patients, the wide use of invasive devices and broad-spectrum antimicrobials used, the intensive care unit (ICU) is often called the epicentre of infections. In the present study, we quantified the burden of hospital acquired pathology in a Romanian university hospital ICU, represented by antimicrobial agents consumption, costs and local resistance patterns, in order to identify multimodal interventional strategies. METHODS: Between 1st January 2012 and 31st December 2013, a prospective study was conducted in the largest ICU of Western Romania. The study group was divided into four sub-samples: patients who only received prophylactic antibiotherapy, those with community-acquired infections, patients who developed hospital acquired infections and patients with community acquired infections complicated by hospital-acquired infections. The statistical analysis was performed using the EpiInfo version 3.5.4 and SPSS version 20. RESULTS: A total of 1596 subjects were enrolled in the study and the recorded consumption of antimicrobial agents was 1172.40 DDD/ 1000 patient-days. The presence of hospital acquired infections doubled the length of stay (6.70 days for patients with community-acquired infections versus 16.06/14.08 days for those with hospital-acquired infections), the number of antimicrobial treatment days (5.47 in sub-sample II versus 11.18/12.13 in sub-samples III/IV) and they increased by 4 times compared to uninfected patients. The perioperative prophylactic antibiotic treatment had an average length duration of 2.78 while the empirical antimicrobial therapy was 3.96 days in sample II and 4.75/4.85 days for the patients with hospital-acquired infections. The incidence density of resistant strains was 8.27/1000 patient-days for methicilin resistant Staphylococcus aureus, 7.88 for extended spectrum ß-lactamase producing Klebsiella pneumoniae and 4.68/1000 patient-days for multidrug resistant Acinetobacter baumannii. CONCLUSIONS: Some of the most important circumstances collectively contributing to increasing the consumption of antimicrobials and high incidence densities of multidrug-resistant bacteria in the studied ICU, are represented by prolonged chemoprophylaxis and empirical treatment and also by not applying the definitive antimicrobial therapy, especially in patients with favourable evolution under empirical antibiotic treatment. The present data should represent convincing evidence for policy changes in the antibiotic therapy.

[Bacterial multiresistance emergence in South-Western Romania]. / Emergenta multirezistentei bacteriene în partea de Sud-Vest a României.

INTRODUCTION: European Centre for Diseases Control (ECDC), involved in the surveillance of nosocomial infections (NI) and resistance to antimicrobials (AMR) in Europe, estimates 4 million IN/year, among whom 37,000 deceased, out of which half are determined by multiresistant germs (MDR). A phenomenon encountered more and more often is that of pan-resistance of germs, without the option for an optimal antibiotherapy. The allarming increase of AMR is a phenomenon which our country also faces in the present. MATERIAL, METHOD, RESULTS: Resistance rate registered in Intensive Care Units in Timisoara during 2005-2007 (when we participated in the Helics European network) situates us among the last places among the European countries that participated--with 50-60% MRSA strains, 24% E. coli BLSE strains, 62,7% K. pneumoniae BLSE strains, 34% P. aeruginosa BLSE. Furthermore, data registered in ambulatory in the South-West part of Romania during 2006-2007 (processed by the greatest private laboratory in the region) are not more optimistic--26% MRSA strains, 4,25% E. coli BLSE, 12,49% K. pneumoniae BLSE, 8,69% P. aeruginosa BLSE. CONCLUSIONS: As the management of MDR produced infections requires huge costs, a better antibiotic policy in the Romanian hospitals and ambulatory is compulsive, being more efficient to spend for control than for the treatment of these infections.

[Aminoglycoside resistance of enterobacteria isolated from urinary infections in surgical departments]. / Rezistenta la aminoglicozide a enterobacteriilor izolate din infectii urinare în sectii cu profil chirurgical.

The aim of the study was to determine the aminoglycosides resistance of Enterobacteriaceae strains isolated from urocultures. Identification of the germs was performed by the API system (BioMerieux) and susceptibility tests was performed by disk-diffusion test (CLSI standards) and with API strips. For detecting the resistance to aminoglycosides we used gentamicin, tobramycin, netilmicin and amikacin. From 2500 urine samples we isolated 673 microbial strains, from which 531 were Enterobacteriaceae, especially E. coli, 57.62% and Klebsiella pneumoniae pneumoniae, 27.68% strains. We observed natural maintained sensibility to aminoglycosides at 55.17% from all the strains we have studied The high prevalence of aminoglycosides resistance of Enterobacteriaceae strains is explained by prolonged antibiotic therapy of patients with invasive diagnostic and therapeutic procedures. A rational policy in prescribing antibiotics in this department is therefore mandatory.

[Antibiotic resistance patterns in Acinetobacter spp. strains isolated from hospital environment]. / Pattern-uri de rezistenta la antibiotice ale unor tulpini de Acinetobacter spp. izolate din mediul spitalicesc.

INTRODUCTION: The Acinetobacter species are ubiquitary germs isolated more and more frequently, Acinetobacter baumannii being currently considered the second strictly aerobic microorganism involved in the ethiology of severe nosocomial infections. Acinetobacter baumannii is usually encountered in surgery and intensive care units, especially in patients with depressed immunity, in which various locations are possible, the most frequvent being the respiratory tract infections, urinary tract infections and bacteriemia. MATERIAL AND METHOD: The study used 52 strains of Acinetobacter spp. isolated from 1131 biological samples (bronchial aspirat, urine, wound secretion, blood, pus, CFS) obtained from the patients of the Timisoara Country Hospital. Identification of germs was performed using the API (BioMerieux) system, and the antibiotics sensitivity testing was made by disk diffusion testing (Kirby-Bauer), with automatic reading and phenotyping through the Osiris Evolution (BioRad) system. RESULTS: The study of resistance to beta-lactamines has pointed out the predominance of penicillinase and cephalosporinase producing strains, 55.77% of the tested ones being part of this phenotype. 90.38% of the strains were resistant to one or more aminoglycosides. Of the tested strains 76.93% were resistant to fluoroquinolones, 86.54% to trimethoprim-sulphamethoxazole, and only 21.15% to tethracycline. CONCLUSIONS: Among the emerging pathogens involved in the nosocomial infections, Acinetobacter baumannii strains have become, in the past decades, a real health issue, due to the variety and seriousness of clinical symptoms. Through the constant increase of the cases number, and the difficulty of applying an effective treatment, the above-mentioned strains showed a multiple resistance to antibiotics.