[Adequacy of the consumption of antipseudomonal antibiotics after changes in the 2019 EUCAST criteria]. / Adecuación de la prescripción de antibióticos antipseudomónicos tras los cambios en los criterios EUCAST 2019.

OBJECTIVE: In 2019, the European Committee for the Study of Antibiotic Susceptibility modified the categories of antibiotic susceptibility tests to include the term "susceptible with increased exposure". Following the dissemination of local protocols reflecting these modifications, the aim of our study was to analyse whether prescribers have adapted to them and the clinical impact in cases of inadequacy. METHODS: Observational and retrospective study of patients with infection who received antipseudomonal antibiotics from January to October 2021 in a tertiary hospital. RESULTS: Non-adherence to the guideline recommendations was 57.6% in the ward and 40.4% in the ICU (p<0.05). In both the ward and ICU, the group with the most prescriptions not by the guideline recommendations were aminoglycosides (92.9% and 64.9% respectively) for using suboptimal doses, followed by carbapenems (89.1% and 53.7% respectively) for not administering an extended infusion. On the ward, the mortality rate during admission or at 30 days in the inadequate therapy group was 23.3% vs 11.5% in those who received adequate treatment (OR: 2.34; 95% CI 1.14-4.82); in ICU there were no statistically significant differences. CONCLUSIONS: The results show the need to implement measures to ensure better dissemination and knowledge of key concepts in antibiotic management, to ensure increased exposures, and to be able to provide better infection coverage, as well as to avoid amplifying resistant strains.

[Utilization study in real clinical practice of ceftolozane/tazobactam vs aminoglycosides and/or colistin in the treatment of multirresistant or extremely resistant Pseudomonas aeruginosa]. / Estudio de utilización en práctica clínica real de ceftolozano/tazobactam frente a aminoglucósidos y/o colistina en el tratamiento de Pseudomonas aeruginosa.

OBJECTIVE: Comparative "real life" data on the effectiveness and safety of ceftolozane/tazobactam (C/T) versus other regimens (aminoglycosides/colistin/combination), in the treatment of multi-resistant (MDR) and extremely resistant (XDR) Pseudomonas aeruginosa (PA), are needed to establish positions. METHODS: Observational, retrospective study of patients with microbiological confirmation of MDR and XDR PA from July 2016 up to December 2018 in a tertiary hospital. Variables: age, sex, comorbidities, risk factors for multidrug resistance, variables related to infection, source of infection, microorganism and type of sample, antibiotic treatment, clinical cure, microbiological cure, recurrence, mortality on admission and 30 days post-discharge. Patients were classified according to received antibiotic treatment, C/T or aminoglycosides/colistin/combination. RESULTS: A total of 405 patients with PA MDR and XDR infection (73.1% men, mean age 63 ± 15 years) were studied. An 87.1% of PA XDR and a 12.9% MDR were observed. All patients received C/T as targeted therapy and in the aminoglycosides/colistin/combination group were 73.5%. Patients in the C/T group present worse prognostic factors: septic shock (30.0%) and catheterization (90.0%) (p<0.05). There were not statistically significant differences in microbiological cure (p=0.412), recurrence (p=0.880) and clinical cure (p=0.566). There were not statistically significant differences in mortality at admission (p=0.352) or at 30 days after discharge (p=0.231). A 17.2% of the patients with aminoglycosides/colistin/combination had acute kidney injury according to RIFLE criteria and 4.3% with C/T. CONCLUSIONS: The data obtained suggest that there have been no differences in effectiveness (clinical or microbiological cure) in favour of C/T, although, in the period studied, it was used in most cases in multitreated patients with a worse prognosis. Randomized and prospective studies would be needed to establish an adequate positioning.

Antimicrobial activity of ceftolozane-tazobactam against multidrug-resistant and extensively drug-resistant Pseudomonas aeruginosa clinical isolates from a Spanish hospital.

OBJECTIVE: Our objective was to evaluate the in vitro activity of ceftolozane-tazobactam against multidrug resistant (MDR) and extensively drug-resistant (XDR) non metallo-ß-lactamase producing Pseudomonas aeruginosa clinical isolates at Hospital Universitario Miguel Servet (Zaragoza, Spain) from February 2016 to October 2017. METHODS: We evaluated the in vitro activity of ceftolozane-tazobactam and other antipseudomonal antibiotics against 12 MDR and 117 XDR non metallo-ß-lactamase producing P. aeruginosa isolates. Ceftolozane-tazobactam minimal inhibitory concentrations (MICs) were determined by MIC gradient diffusion test strip. RESULTS: Among the 129 MDR/XDR isolates included, 119 (92.2%) were susceptible to ceftolozane-tazobactam, and ten (7.8%) were resistant. MIC50 was 2 mg/L, and MIC90 4 mg/L. Ceftolozane-tazobactam was the second most active antibiotic after colistin, overtaking amikacin. CONCLUSIONS: Ceftolozane-tazobactam is a valuable treatment option for MDR and XDR P. aeruginosa infections in our setting.

Genotyping of Mycobacterium tuberculosis over two periods: a changing scenario for tuberculosis transmission.

OBJECTIVE: To evaluate changes in the molecular epidemiology of tuberculosis (TB) in Zaragoza, Spain, over a decade that has seen large social and health changes, including the attenuation of the human immunodeficiency virus (HIV) epidemic and increased immigration. DESIGN: A population-based molecular study was conducted using standard restriction fragment length polymorphism IS6110 typing that included all patients with bacteriologically confirmed TB living in the Zaragoza area from 2001 to 2004. The current situation was compared with that described in a previous study from 1993 to 1995. RESULTS: A total of 454 Mycobacterium tuberculosis isolates were genotyped; 239 (52.6%) were grouped in 45 clusters composed of 2 to 85 isolates. Independent risk factors for clustering were identified. The main differences with the previous study were the increase of TB cases among immigrants, a decrease in HIV-TB co-infected patients and the occurrence of a large TB outbreak involving 85 patients (M. tuberculosis Zaragoza [MTZ] strain). CONCLUSION: A change in the epidemiological pattern of TB has been observed in the last years. TB transmission is more common among the Spanish-born population, while foreign birth is significantly less associated with clustering. A single epidemic strain caused 18.7% of all TB cases.

Mycobacterium malmoense lymphadenitis in Spain: first two cases in immunocompetent patients.

Reported here are two cases of Mycobacterium malmoense lymphadenitis that occurred in two immunocompetent children in Spain. To the best of our knowledge, these are the first documented cases of extrapulmonary infection by M. malmoense in Spain. This report serves to draw attention to this emerging nontuberculous mycobacterium that is gaining increasing recognition as a pulmonary and extrapulmonary pathogen in different countries.