Reliability of a Screening Method Using Antibiotic Disks to Detect Carbapenemases in Glucose-Nonfermenting Gram-Negative Microorganisms From Clinical Samples of a Regional Hospital in Southeastern Spain.

BACKGROUND: Infections by glucose-nonfermenting gram-negative bacilli (NFGNB) pose a major public health problem due to multiresistance to beta-lactam antibiotics, especially plasmid-borne carbapenemases. Their detection by microbiology laboratories is challenging, and there is a need for easy-to-use and reliable diagnostic techniques. Our objective was to evaluate an in-house screening method to presumptively detect carbapenemases in NFGNB in a simple and clinically useful manner. METHODS: The study included 175 NFGNB isolates from urinary, respiratory, and rectal samples. In a triple assay, isolates were incubated at 37°C for 24 h on three solid-culture media: MacConkey II Agar, 5% Sheep Blood Columbia Agar and Mueller Hinton II Agar; meropenem (MEM) and cefepime (FEP) disks were employed for screening. Studies were then performed on the inhibition halo diameter, scanning effects, and the appearance of mutant colonies, which were compared with those observed using the colorimetric Neo-Rapid CARB Kit and immunochromatography (NG5-Test Carba and K-Set for OXA-23). Receiver operating characteristic curves were constructed for these data. RESULTS: Carbapenemases were expressed by 79/175 (45.1%): 19 Pseudomonas aeruginosa and 60 Acinetobacter baumannii. Optimal inhibition halo diameter cutoffs to detect this resistance on 5% sheep blood agar were as follows: 6 mm (MEM) and 6.5 mm (FEP) for P. aeruginosa (in the absence of scanning effects and mutations) and 10.5 mm (MEM) and 16 mm (FEP) for A. baumannii (even in the presence of scanning effects). CONCLUSION: The combined utilization of MEM and FEP antibiotic disks in 5% sheep blood agar, measuring their inhibition haloes, offers an effective method to predict the presence of carbapenemases as resistance mechanism in P. aeruginosa and A. baumannii.

Antibiotic Resistance Changes in Gram-Positive Bacteria from Urine Cultures: Development Analysis in a Health Area of South-East Spain.

This study analyzed the epidemiology and antibiotic susceptibility profile of significant bacteriuria and assessed the impact of adopting EUCAST criteria on antibiotic resistances. A systematic review was performed on publications in English or Spanish between 1 January 2010 and 30 June 2021 on the susceptibility of Gram-positive bacteria isolated in urinary samples in Europe. A retrospective descriptive study was also conducted on the results of 21,838 urine cultures with presumptive urinary tract infection (UTI) obtained during the past five years by the Department of Microbiology of the Virgen de las Nieves University Hospital (Granada, Spain). The activity of various antibiotics was determined, differentiated among various populations, and interpretations compared according to the application of EUCAST or CLSI criteria. Among 21,838 cases of significant bacteriuria, 27.69% were by Gram-positive bacteria, which were Enterococcus faecalis in 19.04% and Enterococcus faecium in 3.92%. The susceptibility profile remained stable for most antibiotics except for levofloxacin for E. faecalis and Staphylococcus aureus and nitrofurantoin for E. faecium. The resistance of Enterococcus spp. and Staphylococcus spp. to glycopeptides was exceptionally low in our setting. No significant difference in the prevalence of methicillin-resistant Staphylococcus aureus was observed between hospital (26.67%) and community (28.85%) samples. Resistances in our local setting remain stable and appear to be lower than reported in other studies. The adoption of EUCAST vs. CLSI criteria did not produce a general change in resistance rates. Findings suggest the need to revise certain empirical criteria, such as aminoglycoside synergy for Enterococcus and for community-origin S. aureus.

Evolution of Antibiotic Resistance in Escherichia coli and Klebsiella pneumoniae from Urine Cultures.

OBJECTIVE: Determine the evolution of antibiotic resistance of symptomatic bacteriuria caused by Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) in Granada. MATERIAL AND METHOD: A descriptive retrospective study was carried out, including antibiograms of urine cultures in which microorganisms identified as E. coli and K. pneumoniae, were isolated in the Microbiology laboratory of the Hospital Universitario Virgen de las Nieves (Granada, Spain) between January 2016 and June 2021. RESULTS: E. coli was the most frequent isolate (10,048) and its resistance to ampicillin (59.45%) and ticarcillin (59.59%), and the increase to cefepime (15.07%) and amoxicillin-clavulanic acid (17.67%) is noteworthy. K. pneumoniae (2222) is notable for resistance to Fosfomycin (27.91%) and an increase to ciprofloxacin (37.79%) and amoxicillin-clavulanic acid (36.63%). Resistance is generally higher in hospitalized patients, males, and adults. CONCLUSIONS: Antibiotic resistance to the studied Enterobacteriaceae is on the rise, requiring empirical treatment targeted to the population area.

Cambios en la resistencia antibiótica en episodios de bacteriospermia sintomática: Evolución en un área de salud del sudeste español / Antibiotic resistance changes in episodes of symptomatic bacteriospermia: development in a health area of southeast Spain

Objetivo: La prostatitis crónica bacteriana (PCB) es una entidad de difícil diagnóstico clínico y tratamiento, siendo el estudio microbiológico del semen la principal prueba diagnóstica. Este estudio tuvo como objetivo determinar la etiología y la resistencia antibiótica en pacientes con bacteriospermia sintomática (BPS) en nuestro medio. Material y métodos: Se ha realizado un estudio descriptivo, transversal y retrospectivo, en un Hospital Regional del sudeste español. Los participantes fueron pacientes asistidos en las consultas del Hospital con clínica compatible con PCB entre 2016 y 2021. Se recogieron y analizaron los resultados del estudio microbiológico de la muestra de semen. Se evaluó la etiología y la tasa de resistencia antibiótica de los episodios de BPS. Resultados: El principal microorganismo detectado es Enterococcus faecalis (34,89%), seguido por Ureaplasma spp. (13,74%) y Escherichia coli (10,98%). La tasa de resistencia antibiótica de E. faecalis a las quinolonas (11%) es inferior a estudios previos, mientras que, para E. coli ha sido superior (35%). Destaca la baja tasa de resistencia que muestran E. faecalis y E. coli a fosfomicina y nitrofurantoína. Conclusiones: En las BPS las bacterias grampositivas y las atípicas se establecen como los principales agentes causales de esta entidad. Esto obliga a replantear la estrategia terapéutica utilizada, lo cual evitará el aumento en las resistencias antibióticas, las recidivas y la cronicidad de esta patología. (AU)

Background: Chronic bacterial prostatitis (CBP) is an entity of difficult clinical diagnosis and treatment, being the microbiological study of semen the main diagnostic test. This study aimed to determine the etiology and antibiotic resistance in patients with symptomatic bacteriospermia (SBP) in our environment. Material and methods: A cross-sectional and retrospective descriptive study has been carried out from a Regional Hospital of the Spanish Southeast. The participants were patients assisted in the consultations of the Hospital with clinic compatible with CBP, between 2016 and 2021. The interventions were collection and analysis of the results derived from the microbiological study of the semen sample. The main determinations were the etiology and rate of antibiotic resistance of BPS episodes are analyzed. Results: The main isolated microorganism is Enterococcus faecalis (34.89%), followed by Ureaplasma spp. (13.74%) and Escherichia coli (10.98%). The rate of antibiotic resistance of E. faecalis to quinolones (11%) is lower than previous studies, while for E. coli it has been higher (35%). The low rate of resistance shown by E. faecalis and E. coli to fosfomycin and nitrofurantoin stands out. Conclusions: In the SBP, gram-positive and atypical bacteria are established as the main causative agents of this entity. This forces us to rethink the therapeutic strategy used, which will avoid the increase in antibiotic resistance, recurrences, and chronicity of this pathology.

Evolution of Antibiotic Resistance in Escherichia coli and Klebsiella pneumoniae from Urine Cultures

Objective: Determine the evolution of antibiotic resistance of symptomatic bacteriuria caused by Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) in Granada. Material and Method: A descriptive retrospective study was carried out, including antibiograms of urine cultures in which microorganisms identified as E. coli and K. pneumoniae, were isolated in the Microbiology laboratory of the Hospital Universitario Virgen de las Nieves (Granada, Spain) between January 2016 and June 2021. Results: E. coli was the most frequent isolate (10,048) and its resistance to ampicillin (59.45%) and ticarcillin (59.59%), and the increase to cefepime (15.07%) and amoxicillin-clavulanic acid (17.67%) is noteworthy. K. pneumoniae (2222) is notable for resistance to Fosfomycin (27.91%) and an increase to ciprofloxacin (37.79%) and amoxicillin-clavulanic acid (36.63%). Resistance is generally higher in hospitalized patients, males, and adults. Conclusions: Antibiotic resistance to the studied Enterobacteriaceae is on the rise, requiring empirical treatment targeted to the population area (AU)

Etiología microbiana de la prostatitis crónica bacteriana: revisión sistemática / Microbial etiology of bacterial chronic prostatitis: systematic review

Objectives: The importance of Gram-positive microorganisms and atypical bacteria in chronic bacterial prostatitis (CBP) has recently been described. For this reason, this study analyzes the etiology of CBP, as well as the evolution of antibiotic resistance through a systematic review. Material and methods: A systematic review of studies obtained through the MEDLINE (PubMed) database, related to the etiology and antibiotic resistance profile of CBP, published up July 1, 2021. Results: The most frequent isolated microorganisms that we have found in publications are Enterococcus faecalis (46.90%), Staphylococcus spp. (22.30%), Escherichia coli (15.09%) and atypical bacteria (6.04%). Conclusions: CBP is undergoing and unprecedented change of paradigm. Gram-positive bacteria and atypical bacteria are the main pathogens involved in the aetiology of this entity. This forces us to rethink the therapeutic strategy used, since it is necessary to use antibiotics that assume the etiological change and the profile of antibiotic resistance described. (AU)

Objetivos: Recientemente se ha descrito la importancia de los microorganismos grampositivos y de las bacterias atípicas en la prostatitis crónica bacteriana (PCB). Por ello, en este estudio se analiza la etiología de la PCB, así como la evolución de la resistencia antibiótica a través de una revisión sistemática. Material y métodos: Se ha realizado una revisión sistemática de estudios obtenidos a través de la base de datos MEDLINE (PubMed), relacionados con la etiología y el perfil de resistencia antibiótica de la PCB, publicados con anterioridad al 1 de julio de 2021. Resultados: Los principales microorganismos aislados en los estudios incluidos en la revisión fueron Enterococcus faecalis (46,90%), Staphylococcus spp. (22,30%), Escherichia coli (15,09%) y bacterias atípicas (6,04%). Conclusiones: La PCB está experimentando un cambio de paradigma, ya que las bacterias grampositivas y las atípicas se erigen como los principales agentes causales de esta entidad. Esto obliga a replantear la estrategia terapéutica utilizada, pues es necesario utilizar antibióticos que asuman el viraje etiológico y el perfil de resistencias antibióticas descrito. (AU)