The CARBA-MAP study: national mapping of carbapenemases in Spain (2014-2018).

Introduction: Infections caused by carbapenem-resistant Enterobacterales (CRE) and carbapenem-resistant Pseudomonas aeruginosa, including isolates producing acquired carbapenemases, constitute a prevalent health problem worldwide. The primary objective of this study was to determine the distribution of the different carbapenemases among carbapenemase-producing Enterobacterales (CPE, specifically Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae complex, and Klebsiella aerogenes) and carbapenemase-producing P. aeruginosa (CPPA) in Spain from January 2014 to December 2018. Methods: A national, retrospective, cross-sectional multicenter study was performed. The study included the first isolate per patient and year obtained from clinical samples and obtained for diagnosis of infection in hospitalized patients. A structured questionnaire was completed by the participating centers using the REDCap platform, and results were analyzed using IBM SPSS Statistics 29.0.0. Results: A total of 2,704 carbapenemase-producing microorganisms were included, for which the type of carbapenemase was determined in 2692 cases: 2280 CPE (84.7%) and 412 CPPA (15.3%), most often using molecular methods and immunochromatographic assays. Globally, the most frequent types of carbapenemase in Enterobacterales and P. aeruginosa were OXA-48-like, alone or in combination with other enzymes (1,523 cases, 66.8%) and VIM (365 cases, 88.6%), respectively. Among Enterobacterales, carbapenemase-producing K. pneumoniae was reported in 1821 cases (79.9%), followed by E. cloacae complex in 334 cases (14.6%). In Enterobacterales, KPC is mainly present in the South and South-East regions of Spain and OXA-48-like in the rest of the country. Regarding P. aeruginosa, VIM is widely distributed all over the country. Globally, an increasing percentage of OXA-48-like enzymes was observed from 2014 to 2017. KPC enzymes were more frequent in 2017-2018 compared to 2014-2016. Discussion: Data from this study help to understand the situation and evolution of the main species of CPE and CPPA in Spain, with practical implications for control and optimal treatment of infections caused by these multi-drug resistant organisms.

Evaluating the drop test method in measuring colistin susceptibility of Klebsiella pneumoniae, Escherichia coli and Pseudomonas aeruginosa.

Introduction. Colistin is an antibiotic used to treat Gram-negative bacterial infections, particularly those caused by multidrug-resistant bacteria.Hypothesis/Gap Statement. The broth microdilution (BMD) reference method is the recommended protocol for detecting colistin susceptibility; however, it is laborious and expensive and cannot be performed in all laboratories.Aim. To evaluate the colistin susceptibility in Klebsiella pneumoniae, Escherichia coli and Pseudomonas aeruginosa using an alternative method, which has been referred to as the drop test.Methodology. A 16 µg ml-1 colistin solution was deposited on a Mueller-Hinton agar plate previously swabbed with the strain and incubated overnight, and the presence or absence of an inhibition zone was observed.Results. The categorical agreement (CA) of the drop test with respect to BMD was 100 % when 190 Enterobacterales (19 E. coli and 171 K. pneumoniae) were used, and no major errors (MEs) or very major errors (VMEs) were detected. The CA of the drop test with respect to the BMD was 99.2 % for 119 P. aeruginosa isolates, while no ME was detected and only 1 VME (6.7%) was observed.Conclusion. The drop test is an alternative method for antimicrobial susceptibility testing of colistin against K. pneumoniae and E. coli. It is an adequate method for detecting resistant strains of P. aeruginosa, but susceptible isolates should be confirmed using BMD. The drop test is a simpler alternative to the BMD that does not require additional equipment and allows for the testing of numerous isolates in a short period of time.

[Aseptic meningitis in an adult population. Etiology and utility of molecular techniques in the clinical management of patients]. / Meningitis aséptica en la población adulta. Etiología y utilidad de las técnicas moleculares en el manejo clínico del paciente.

OBJECTIVE: This study describes the epidemiological, clinical and microbiological features of acute aseptic meningitis (AAM) in an adult population, and evaluates the impact of microbiological results on the clinical management of patients. PATIENTS AND METHODS: Cases of AAM were prospectively collected between 2007 and 2010 among immunocompetent patients over 14 years-old. Enteroviruses and herpes viruses were determined using nucleic acids detection in CSF. Demographic and clinical data were retrospectively collected from medical records. RESULTS: A total of 94 patients were included, of whom 84 were diagnosed with viral meningitis (VM). The annual incidence of VM ranged from 2.4 to 15.3 cases per 100,000 inhabitants. An aetiological diagnosis was obtained in 76.2% of the patients with VM, 55 enterovirus, 4 HSV-2, 3 VZV, one HSV-1, and one EBV. Forty five per cent of patients were admitted to hospital and 65.8% of them received antibiotic treatment. A positive result prompted immediate discharge of 80% of inpatients and discontinuation of antibiotic therapy in 94.1% of them. The median duration of admission to hospital in these patients was 2.8±2.9 days. Patients without available results during admission completed the antibiotic treatment, and the median hospital stay was 11.6±4.6 days. CONCLUSIONS: The annual incidence of AAM is variable. Enteroviruses were the main aetiological agent. Molecular tests revealed the aetiology in 76.2% of cases. Almost half of the patients required hospitalisation, and in these cases a positive result can lead to the immediate discharge of patients, and the diagnostic and therapeutic interventions can be reduced.