Outcomes of 23 patients diagnosed with New Delhi metallo-beta-lactamase (NDM)-producing Klebsiella pneumoniae infection treated with ceftazidime/avibactam and aztreonam at a single center in Poland.

PURPOSE: Amongst all etiologic hospital-acquired infection factors, K. pneumoniae strains producing New Delhi metallo-ß-lactamase (KP-NDM) belong to pathogens with the most effective antibiotic resistance mechanisms. Clinical guidelines recommend using ceftazidime/avibactam with aztreonam (CZA + AT) as the preferred option for NDM-producing Enterobacterales. However, the number of observations on such treatment regimen is limited. This retrospective study reports the clinical and microbiological outcomes of 23 patients with KP-NDM hospital-acquired infection treated with CZA + AT at a single center in Poland. METHODS: The isolates were derived from the urine, lungs, blood, peritoneal cavity, wounds, and peritonsillar abscess. In microbiological analysis, mass spectrometry for pathogen identification, polymerase chain reaction, or an immunochromatographic assay for detection of carbapenemase, as well as VITEK-2 system, broth microdilution, and microdilution in agar method for antimicrobial susceptibility tests were used, depending of the pathogens' nature. CZA was administered intravenously (IV) at 2.5 g every eight hours in patients with normal kidney function, and aztreonam was administered at 2 g every eight hours IV. Such dosage was modified when renal function was reduced. RESULTS: KP-NDM was eradicated in all cases. Four patients (17.4%) died: three of them had a neoplastic disease, and one - a COVID-19 infection. CONCLUSION: The combination of CZA + AT is a safe and effective therapy for infections caused by KP-NDM, both at the clinical and microbiological levels. The synergistic action of all compounds resulted in a good agreement between the clinical efficacy of CZA + AT and the results of in vitro susceptibility testing.

Dissemination of extensively drug-resistant NDM-producing Providencia stuartii in Europe linked to patients transferred from Ukraine, March 2022 to March 2023.

BackgroundThe war in Ukraine led to migration of Ukrainian people. Early 2022, several European national surveillance systems detected multidrug-resistant (MDR) bacteria related to Ukrainian patients.AimTo investigate the genomic epidemiology of New Delhi metallo-ß-lactamase (NDM)-producing Providencia stuartii from Ukrainian patients among European countries.MethodsWhole-genome sequencing of 66 isolates sampled in 2022-2023 in 10 European countries enabled whole-genome multilocus sequence typing (wgMLST), identification of resistance genes, replicons, and plasmid reconstructions. Five bla NDM-1-carrying-P. stuartii isolates underwent antimicrobial susceptibility testing (AST). Transferability to Escherichia coli of a bla NDM-1-carrying plasmid from a patient strain was assessed. Epidemiological characteristics of patients with NDM-producing P. stuartii were gathered by questionnaire.ResultswgMLST of the 66 isolates revealed two genetic clusters unrelated to Ukraine and three linked to Ukrainian patients. Of these three, two comprised bla NDM-1-carrying-P. stuartii and the third bla NDM-5-carrying-P. stuartii. The bla NDM-1 clusters (PstCluster-001, n = 22 isolates; PstCluster-002, n = 8 isolates) comprised strains from seven and four countries, respectively. The bla NDM-5 cluster (PstCluster-003) included 13 isolates from six countries. PstCluster-001 and PstCluster-002 isolates carried an MDR plasmid harbouring bla NDM-1, bla OXA-10, bla CMY-16, rmtC and armA, which was transferrable in vitro and, for some Ukrainian patients, shared by other Enterobacterales. AST revealed PstCluster-001 isolates to be extensively drug-resistant (XDR), but susceptible to cefiderocol and aztreonam-avibactam. Patients with data on age (n = 41) were 19-74 years old; of 49 with information on sex, 38 were male.ConclusionXDR P. stuartii were introduced into European countries, requiring increased awareness and precautions when treating patients from conflict-affected areas.

Changes in bacterial flora and antibiotic resistance in clinical samples isolated from patients hospitalized in the Military Institute of Medicine in Warsaw, Poland, between 2005-2012

BACKGROUND: Hospital infections have become an important problem. Knowledge of microbiological situations both helps in ensuring that the optimal choice of antibacterial treatment is made, and in improving the results of the selected therapy. OBJECTIVE: In this paper, both the changes in the bacterial flora of patients hospitalized in the Military Institute of Medicine, and the bacterial resistance to antimicrobials were analyzed. MATERIAL AND METHODS: Data were collected between 2005 and 2012. The identification and testing of pathogens, susceptibility tests, and analysis of bacterial resistance mechanisms to antibiotics were performed according to current guidelines. RESULTS: A total number of 28,066 bacterial strains were isolated. The most frequently isolated pathogens were Gram-negative bacteria (n=18,021; 64% of all isolated bacteria), including Enterobacteriaceae (71%) and non-Enterobacteriaceae (29%). The total number of isolated Gram-positive bacteria (n=10,045; 36% of all isolates) included Staphylococcus spp. (65%) and Enterococcus spp. (35%). The highest increase in the number of infections was caused by Enterobacteriaceae. The number of Staphylococcus aureus and coagulase negative Staphylococcus resistant to methicillin decreased. Analyzed alert pathogens with resistance phenotypes were highly susceptible to a single type of antibiotic. All multidrug resistant Gram-negative bacteria (except those naturally resistant to colistin) were susceptible to colistin. All methicillin resistant S. aureus and methicillin resistant coagulase negative Staphylococci were susceptible to vancomycin and linezolid. All MSSA strains were susceptible to cloxacillin, all Enterococcus faecium strains to ampicillin, and all VRE strains were susceptible to linezolid and tigecycline.

Respiratory infections in travelers returning from the tropics.

Respiratory tract infections (RTIs), beside diarrheas, skin lesions, and fevers of unknown origin, are one of the most common health problems acquired by travelers going to tropical and subtropical countries. Visitors to African, Asian, or South American destinations, typically characterized by harsh environmental conditions and poor sanitation standards, are at risk of exposure to a large number of pathogens causing infectious diseases. The infections are transmitted from contaminated food and water, through the air, direct contact, or by insects. The main modes of RTIs transmission include droplet infection and direct contact. The clinical spectrum of RTIs in travelers is broad, from upper respiratory tract infections, pharyngitis, bronchitis, pneumonia, to influenza-like illness. The spectrum of microbial agents causing respiratory infections include numerous viruses and bacteria, rarely fungi, and parasites. Most travelers complain of mild infections, only a small minority seek medical assistance and report to health care facilities. Because of the risk of importing pathogens into Europe or North America and transferring them onto the local population, it is important to present the scale of the problem in relation to rapid development of tourism industry and an increasing number of intercontinental journeys. The aim of the study was to discuss the occurrence of travel-related respiratory infections among representatives of temperate climate traveling to and returning from the tropics.

Effectivity of antiseptics against some pathogens.

INTRODUCTION: The efficacy of antiseptics against bacteria and fungi is different. The choice of optimal antiseptic solution is very important in prophylaxis of hospital infections. MATERIAL AND METHODS: In this study the efficacy of different antiseptics against some pathogens (Klebsiella pneumoniae ESBL (+), Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus MRSA, Candida dublinensis) was analyzed. The disc diffusion, similar to the method used in antibiotic sensitivity testing was applied. We assumed that the size of inhibition zone of bacterial growth corresponds with the efficacy of antiseptic. RESULTS AND CONCLUSION: The 2% alcoholic solution of chlorhexidine was the most effective antiseptic in our study.

Bacteraemia caused by Lactobacillus casei in a patient after cardiac surgery. A case report.

BACKGROUND: Bacteria of the Lactobacillus family are a part of the physiological flora of the oral cavity, gastrointestinal tract, and urinary tract. We have used them in the food industry as probiotics and supplements. In some settings, rod-shaped lactic acid bacteria may become pathogenic. It may occur in immunocompromised or heart disease patients after cardiac surgery, patients with disturbed intestinal wall permeability, or those treated with broad-spectrum antibiotics. CASE PRESENTATION: We present rare bacteraemia induced by the probiotic bacterium Lactobacillus casei in a 63-year-old patient after the attempted removal of ICD electrodes, complicated by acute regurgitation of the tricuspid valve. The patient underwent urgent cardiac surgery, the electrode elements were removed, and the tricuspid valve was replaced with a biological prosthesis. After surgery, the patient required intensive, multidisciplinary treatment with mechanical ventilation, continuous renal replacement therapy, broad-spectrum empirical antibiotic therapy, parenteral nutrition, and blood product transfusion because of multiple organ failure. On the 14th day of hospitalisation, the clinical symptoms of septic shock were observed. The microbiological investigation was performed, and Lactobacillus casei was cultured from a dialysis catheter sample. Dedicated antimicrobials were administered, and the patient was discharged home in good overall condition. CONCLUSIONS: The present case shows that the promoted use of probiotics must be cautiously administered to patients in severe conditions, especially when accompanied by reduced immune system efficiency symptoms.

The Clinical Manifestation of SARS-CoV-2 in Critically Ill Patients with Klebsiella pneumoniae NDM Hospitalized in the ICU of a Modular Hospital during the Third Wave of the Pandemic in Poland-An Observational Cohort Study.

There is limited information on the clinical characteristics of critically ill patients infected with SARS-CoV-2 and Klebsiella pneumoniae NDM. The objective of this study was to describe such a group of patients hospitalised in the intensive care unit of a large academic hospital during the third wave of the COVID-19 pandemic in Poland. Between 1 March and 30 June 2021, 103 patients were hospitalised, of whom 23 (22.3%) were positive for K. pneumoniae NDM; 14 (61%) of those patients died. Their hospitalisation time varied between 9 and 47 days. Five of the 23 patients (21.7%) were otherwise healthy. In contrast, the others suffered from cardiovascular problems (11, 47.8%), obesity (6, 26.1%), diabetes (5, 21.7%), neurological problems (4, 17.4%), or kidney disease (1, 4.3%); 4 (17.4%) were heavy smokers, and 1 (4.3%) had a history of alcohol abuse. K. pneumoniae NDM was isolated from urine samples of all patients. In 17 patients (73.9%), it was also isolated from other sources: from the respiratory tract in 10 (43.8%), from the blood in 2 (8.7%), and the central venous catheter was contaminated in 1 case (4.3%). Fourteen of the patients (60.9%) were colonised K. pneumoniae NDM. In four patients (17.4%), bacterial and fungal coinfection occurred. In one case (4.4%), two fungal species, Candida albicans and Candida glabrata, were isolated simultaneously. The most frequently administered antimicrobial agent was colistin (60.9%), followed by meropenem (47.8%), vancomycin (47.8%), ceftriaxone (34.8%), linezolid (30.4%), piperacillin/tazobactam (30.4%), and trimethoprim/sulfamethoxazole (30.4%). Other less-frequently administered agents included amikacin, amoxicillin/clavulanate, tigecycline, ciprofloxacin, fosfomycin, clindamycin, and cloxacillin. Fluconazole was administered in 14 patients (60.7%) and micafungin was administered in 2 (8.7%).

Bloodstream Infections in the Intensive Care Unit: a Single-Center Retrospective Bacteriological Analysis Between 2007 and 2019.

Hospital-acquired bloodstream infections are a severe worldwide problem associated with significant morbidity and mortality. This retrospective, single-center study aimed to analyze bloodstream infections in patients hospitalized in the intensive care unit of the Military Institute of Medicine, Poland. Data from the years 2007-2019 were analyzed. When the infection was suspected, blood samples were drawn and analyzed microbiologically. When bacterial growth was observed, an antimicrobial susceptibility/resistance analysis was performed. Among 12,619 analyzed samples, 1,509 were positive, and 1,557 pathogens were isolated. In 278/1,509 of the positive cases, a central line catheter infection was confirmed. Gram-negative bacteria were the most frequently (770/1,557) isolated, including Acinetobacter baumannii (312/770), Klebsiella pneumoniae (165/770; 67/165 were the isolates that expressed extended spectrum beta-lactamases (ESBL), 5/165 isolates produced the New Delhi metallo-ß-lactamases (NDM), 4/165 isolates expressed Klebsiella pneumoniae carbapenemase (KPC), and 1/165 isolate produced OXA48 carbapenemase), Pseudomonas aeruginosa (111/770; 2/111 isolates produced metallo-ß-lactamase (MBL), and Escherichia coli (69/770; 11/69 - ESBL). Most Gram-positive pathogens were staphylococci (545/733), mainly coagulase-negative (368/545). Among 545 isolates of the staphylococci, 58 represented methicillin-resistant Staphylococcus aureus (MRSA). Fungi were isolated from 3.5% of samples. All isolated MRSA and methicillin-resistant coagulase-negative Staphylococcus (MRCNS) strains were susceptible to vancomycin, methicillin-sensitive Staphylococcus aureus (MSSA) isolates - to isoxazolyl penicillins, and vancomycin-resistant Enterococcus (VRE) - to linezolid and tigecycline. However, colistin was the only therapeutic option in some infections caused by A. baumannii and KPC-producing K. pneumoniae. P. aeruginosa was still susceptible to cefepime and ceftazidime. Echinocandins were effective therapeutics in the treatment of fungal infections.

Preliminary trial of 24 vs 72 hour perioperative meropenem in patients with ESBL-producing Enterobacterales bacteriuria scheduled for urological procedures.

Introduction: Antimicrobial prophylaxis is an important issue in positive urine culture patients undergoing endourological procedures or extracorporeal shock wave lithotripsy (ESWL). It is especially recognized in asymptomatic bacteriuria patients of alarm pathogen etiology. We designed a preliminary study to determine optimal duration of antibiotic prophylaxis in patients undergoing endourological procedures or ESWL with asymptomatic bacteriuria caused by Enterobacterales with extended spectrum beta-lactamase positive (ESBL+) type resistance. Material and methods: A total of 60 patients with confirmed ESBL+ Enterobacterales bacteriuria were admitted for endourological procedures or ESWL. The patients were randomized into two groups - a one-day (n = 33) and a three-day (n = 27) period of perioperative antibiotic prophylaxis with meropenem. In both groups on the following day after the procedure (24 hours after the procedure) and 7 days after the procedure serum inflammation markers were assessed. Results: Values of white blood count, C-reactive protein and procalcitonin prior to, 24 hours and seven days after the procedure clearly showed no statistically significant differences between groups that have received a one-day and three-day antibiotic regimen. Conclusions: In patients with ESBL+ Enterobacterales asymptomatic bacteriuria undergoing endourological procedures or ESWL a 72-hour perioperative meropenem prophylaxis showed no superiority over a 24-hour regimen. Further studies will be carried out to establish optimal prophylaxis for specific endourological procedures and to test safety of a single dose regimen.

[The comparison of different bronchial aspirate culturing methods in patients with ventilator-associated pneumonia (VAP)]. / Porownanie roznych sposobow pobierania materialu z drzewa oskrzelowego do badan mikrobiologicznych.

BACKGROUND: Although broncho-alveolar lavage (BAL) culture and protected specimen brush (PSB) are regarded as the most effective methods in the diagnosis of VAP, a simple endotracheal aspiration (EA) is frequently performed during routine care, because of its simplicity and low cost. We compared the effectiveness of EA with BAL and PSB in VAP patients. METHODS: Sixty-one adult VAP patients, ventilated for longer than 48 h, were cultured with all three methods. RESULTS: Positive cultures were obtained from 63.9% of patients, with Acinetobacter baumannii being the most common pathogen. There was a high positive correlation between simple aspirates and BAL (k 0.817, CI 0.664-0.840, p <0.001) and aspirates and PSB (k 0.667, CI 0.483-0.871, p <0.001). CONCLUSION: Because of the high sensitivity of bronchial aspirate culturing, compared to BAL and PSB, it can be used successfully in most cases.

Infective endocarditis - can we treat it more effectively?

Infective endocarditis (IE), despite the diagnostic and therapeutic advances, still remains a serious disease associated with high mortality and serious complications. The present guidelines of the European Cardiology Society of 2015 recommend administration of the antibiotics indicated in empirical therapy for multiple weeks and in targeted treatment often for 6-8 weeks. This is associated with a risk of adverse effects of antibiotic therapy in the form of nephro- and/or hepatotoxicity and an increased risk of infections with Clostridioides difficile, while long-term hospitalisation is associated with high non-drug costs. The recommendations developed by the Austrian Society for Infectious Diseases and Tropical Medicine list dalbavancin among the new antibiotics that may find application in the treatment of IE of staphylococcal aetiology. This antibiotic is a lipoglycopeptide antibiotic alternative to vancomycin in the treatment of Staphylococcus aureus MRSA infections, especially in a situation where the minimum inhibitory concentration for vancomycin is high but below the breakpoint. Dalbavancin has very good pharmacokinetic and pharmacodynamic properties, with a long duration of action of up to 14 days after administration of a single dose (1500 mg in a 30-minute infusion). This antibiotic is characterised by high clinical efficacy with good treatment tolerance and safety profile, without causing toxic effects in internal organs in comparison with vancomycin. In view of its safety, clinical efficacy and convenient dosing, dalbavancin may prove a useful therapeutic option in the treatment of IE.

Frequency of infections caused by ESBL-producing bacteria in a pediatric ward - single-center five-year observation.

INTRODUCTION: Infections caused by Enterobacteriaceae producing extended-spectrum ß-lactamases (ESBLs) are a serious therapeutic and clinical problem. An increasing role of ESBL(+) pathogens is observed in both community- and hospital-acquired infections. The aim of the study was to assess the incidence and the risk factors for ESBL(+) bacteria infection in a pediatric ward during a 5-year period. MATERIAL AND METHODS: The medical documentation data of patients hospitalized in the Department of Pediatrics, Pediatric Nephrology and Allergology between 2011 and 2015 were subjected to a retrospective analysis. Cases of ESBL(+) bacterial infections were analyzed in detail. RESULTS: 0.57% (46) of all the hospitalizations (8015) during the 5-year observation period in our department were caused by ESBL (+) pathogens. It constituted 8.5% of all positive microbiological cultures obtained. The analysis revealed an increasing trend in the number of ESBL (+) infections throughout the observed period. 43.5% of patients were only asymptomatic carriers. In 71.7% urinary tract structural and functional abnormalities were present. 76.1% of patients had been hospitalized previously and 60.9% had undergone urinary tract invasive procedures. CONCLUSIONS: The results confirm the rising trend of ESBL (+) infections during the observed period. ESBL (+) bacteria were isolated primarily in previously hospitalized children with particular reference to urinary tract invasive procedures during hospitalizations. Moreover, the study showed that patients with urogenital disorders and non-urinary chronic diseases are more susceptible to these priority pathogen infections.

In vitro analysis of the minimal inhibitory concentration values of different generations of anti-methicillin-resistant Staphylococcus aureus antibiotics.

Methicillin-resistant Staphylococcus aureus (MRSA) resistance to antimicrobials may result in the increased risk of treatment failure. The objective of the study was to analyse in vitro MRSA susceptibility to vancomycin, linezolid, daptomycin, tigecycline, ceftaroline, dalbavancin, clindamycin, ciprofloxacin and trimethoprim/sulfamethoxazole. All MRSA strains isolated from hospitalised patients were analysed according to the current microbiological recommendations. Finally, a total of 124 MRSA strains were analysed; all were susceptible to tested antibiotics. Dalbavancin had the lowest minimum inhibitory concentration (MIC), and vancomycin the highest MIC value. There were 28/124 strains of MRSA susceptible for clindamycin, 36/124 for ciprofloxacin and 121/124 for trimethoprim/sulfamethoxazole. Dalbavancin was the most effective antimicrobial in our study.

Dalbavancin treatment in a deep sternal wound MRSA infection after coronary artery bypass surgery: a case report.

BACKGROUND: A deep sternal wound infection (DSWI) can become a severe complication after cardiac surgery, with in-hospital mortality rates reaching up to 35%. Staphylococci, particularly methicillin resistant Staphylococcus aureus (MRSA), play important roles in its etiology. CASE PRESENTATION: This case report presents a patient who underwent coronary artery bypass surgery, and suffered postoperatively from a DSWI caused by MRSA. The pathogen was susceptible to vancomycin and rifampicin in vitro; however, this therapy was clinically ineffective. Both clinical improvement and MRSA eradication were achieved after surgical debridement of the wound and the intravenous administration of dalbavancin. CONCLUSIONS: We decided to administer dalbavancin because of its convenient pharmacological profile. The patient's tolerance of the antimicrobial was good, the biochemical markers of inflammation returned to the normal ranges, and the microbiological results one week after the dalbavancin administration were negative. A good clinical outcome was achieved with both the surgery and antimicrobial administration. In this case, dalbavancin was more effective in the treatment of the sternal and surrounding tissue infections caused by MRSA, when compared to vancomycin.

High altitude pulmonary edema in mountain climbers.

Every year thousands of ski, trekking or climbing fans travel to the mountains where they stay at the altitude of more than 2500-3000m above sea level or climb mountain peaks, often exceeding 7000-8000m. High mountain climbers are at a serious risk from the effects of adverse environmental conditions prevailing at higher elevations. They may experience health problems resulting from hypotension, hypoxia or exposure to low temperatures; the severity of those conditions is largely dependent on elevation, time of exposure as well as the rate of ascent and descent. A disease which poses a direct threat to the lives of mountain climbers is high altitude pulmonary edema (HAPE). It is a non-cardiogenic pulmonary edema which typically occurs in rapidly climbing unacclimatized lowlanders usually within 2-4 days of ascent above 2500-3000m. It is the most common cause of death resulting from the exposure to high altitude. The risk of HAPE rises with increased altitude and faster ascent. HAPE incidence ranges from an estimated 0.01% to 15.5%. Climbers with a previous history of HAPE, who ascent rapidly above 4500m have a 60% chance of illness recurrence. The aim of this article was to present the relevant details concerning epidemiology, pathophysiology, clinical symptoms, prevention, and treatment of high altitude pulmonary edema among climbers in the mountain environment.

Occurrence of Chlamydia trachomatis in military environment on the example of professional soldiers in the Polish Armed Forces.

This article presents the results of a preliminary study concerning cases of Chlamydia trachomatis infections among professional soldiers in the Polish Armed Forces. Soldiers who declared casual sexual contact with women were investigated in this study regarding the transmission of chlamydial infections by sexual activity. In total, 66 healthy, sexually active professional Polish soldiers, aged between 27 and 44, who didn't report any symptoms of urogenital infection were investigated. Urine samples taken from these patients were investigated using molecular methods (Cobas TaqMan, real-time PCR) in March-April 2012 in the Military Institute of Medicine, Warsaw, Poland. In the investigated group of 66 Polish soldiers, two 33-34 year old men were asymptomatic carriers of Chlamydia trachomatis (3.0%). They confirmed having casual sexual activity without prevention with many women. In the examined group of Polish soldiers the relatively low level of chlamydial infections found may result from the use of preventive measures during sexual activity. According to the examined men, the common use of condoms is mainly connected with the fear of HIV infection. Screening tests for Chlamydia trachomatis in the Polish Armed Forces are not performed, therefore incidence rates of chlamydial infections remain unknown. The authors plan further investigations with a larger group of professional soldiers.

Comparison of in vitro efficacy of ertapenem, imipenem and meropenem in the infections caused by the Enterobacteriaceae strains family.

BACKGROUND: The members of the bacterial Enterobacteriaceae family play an important role in the aetiology of many hospital infections. Some of them are able to produce ß-lactamase, an enzyme which induces the resistance of those bacteria to penicillins, cephalosporins and, in severe infections, to penicillins with ß-lactamase inhibitors. In this situation, the carbapenems become the drugs of choice. The objective of this study was to analyse the in vitro efficacy of three carbapenems: ertapenem, imipenem and meropenem against bacterial species of the Enterobacteriaceae family. METHODS: A total of 99 bacterial species (including ten bacterial species producing the ESBL mechanism), isolated between September 2011 and March 2012 from diagnostic material collected from patients of surgical clinics in the department of motoskeletal system infections and the critical care unit, hospitalised in the Military Institute of Medicine in Warsaw, were analysed. The values of MIC 50 and MIC 90 were recorded. RESULTS: All isolated bacterial species were susceptible to meropenem. One strain of Morganella morganii was resistant to imipenem, while one strain of Enterobacter cloaceae and one strain of Klebsiella pneumoniae were resistant to ertapenem. In the Enterobacteriaceae ESBL(-) group, the values of MIC 50 were 0.006 µg mL-1 for ertapenem, 0.19 µg mL⁻¹ for imipenem, and 0.032 µg mL⁻¹ for meropenem, and the MIC 90 values were: 0.25 µg mL⁻¹, 0.5 µg mL⁻¹ and 0.125 µg mL⁻¹, respectively. In the Enterobacteriaceae ESBL(+) group, the values of MIC 50 were 0.38 µg mL⁻¹, 0.25 µg mL⁻¹, 0.064 µg mL⁻¹, and the values of MIC 90 were 0.5 µg mL⁻¹, 0.25 µg mL⁻¹ and 0.125 µg mL⁻¹, respectively. CONCLUSIONS: All analysed carbapenems had high in vitro efficacy against both Enterobacteriaceae ESBL(-) and Enterobacteriaceae ESBL(+) bacterial species.