Molecular Epidemiology of Multidrug-Resistant Pseudomonas aeruginosa Acquired in a Spanish Intensive Care Unit: Using Diverse Typing Methods to Identify Clonal Types.

The increasing number of infections from multidrug-resistant P. aeruginosa (MDRPA) has compromised the selection of appropriate treatment in critically ill patients. Recent investigations have shown the existence of MDRPA global clones that have been disseminated in hospitals worldwide. We aimed to describe the molecular epidemiology and genetic diversity of the MDRPA acquired by Intensive Care Units (ICU) patients in our hospital. We used phenotypic methods to define the MDRPA and molecular methods were used to illustrate the presence of carbapenemase encoding genes. To characterize the MDRPA isolates, we used MALDI-TOF biomarker peaks, O-antigen serotyping, and multi-locus sequence typing analyses. Our data show that the most widely distributed MDRPA clone in our ICU unit was the ST175 strain. These isolates were further investigated by the whole-genome sequencing technique to determine the resistome profile and phylogenetic relationships, which showed, as previously described, that the MDR profile was due to the intrinsic resistance mechanisms and not the carbapenemase encoding genes. In addition, this study suggests that the combination of environmental focus and cross-transmission are responsible for the spread of MDRPA clones within our ICU unit. Serotyping and MALDI-TOF analyses are useful tools for the early detection of the most prevalent MDRPA clones in our hospital. Using these methods, semi-directed treatments can be introduced at earlier stages and healthcare professionals can actively search for environmental foci as possible sources of outbreaks.

Clinical characteristics of patients with Mycoplasma pneumoniae infection.

OBJECTIVE: To describe the characteristics of patients diagnosed with Mycoplasma pneumoniae infection. METHODS: A retrospective study of clinical and epidemiological characteristics of acute infections by M. pneumoniae confirmed by PCR was carried out in the Navarra Health Service (Spain) in 2014-2018. RESULTS: M. pneumoniae infection was confirmed in 9.5% of analyzed patients. Among 123 confirmed cases, 65% were 5-14 years old, 21.1% <5 years old, and 13.8% were ≥14 years old. Pneumonia was radiologically confirmed in 83.7% of cases, and 22.0% presented extra-respiratory manifestations. A total of 44.7% of cases required hospitalization. Bilateral pneumonia, asthmatic crisis and extra-respiratory manifestations were associated to higher risk of hospitalization (81.3, 72.2 and 66.7%, respectively). Microbiological targeted treatment was monotherapy with macrolides in 60.2% of cases and combined with other antibiotics in 13.0%. CONCLUSION: M. pneumoniae was the cause of acute respiratory infection affecting mainly to children younger than 14 years old and frequently required hospitalization.

[Environmental microbiological control]. / Control microbiológico ambiental.

The environmental microbiological control is necessary to prevent infections associated with certain procedures that are performed at the hospital. In this review the procedures for control of water and dialysis fluids, and air in operating rooms and immunocompromised units are addressed. The dialysis quality management guidelines define the highest levels of chemical, microbiological and endotoxin in purified water and dialysis fluids based on the recommendations of scientific societies. The microbiological control of water and dialysis fluids should include detection of microorganisms and endotoxin levels. Regarding the microbiological air sampling of operating rooms and immunocompromised units the types of clean rooms in which is recommended to perform microbiological air monitoring; the sample collection methods; culture media; incubation conditions; the most common microorganisms, and permissible levels depending on the type of surgery are described.

[Article on SEIMC Procedure No.42: Environmental microbiological monitoring]. / Control microbiológico ambiental.

The inanimate hospital environment is rarely implicated in infection transmission, except among vulnerable patients. Some authors argue against the use of environmental surveillance cultures because the tests can be expensive and time consuming, and because they should not be used instead of quality control and good practices in disinfection and maintenance procedures. Routine environmental sampling is not usually advised, except in situations where sampling is directed by epidemiologic principles, and results can be applied to adopt infection control measures. The incidence of health-care associated infections can be minimised by appropriate maintenance of medical equipment such as endoscope cleaning and disinfection, adherence to water-quality standards for haemodialysis, and to ventilation standards for specialised care environments such as isolation units, or operating rooms. This paper reviews the current knowledge on surveillance cultures in these settings in order to prevent iatrogenic infections in operating and isolation rooms, haemodialysis and endoscope reprocessing units, and cultures related to nosocomial infection outbreaks.

[An analysis of 182 enterococcal bloodstream infections: epidemiology, microbiology, and outcome]. / Análisis de 182 episodios de bacteriemia por enterococo: estudio de la epidemiología, microbiología y evolución clínica.

INTRODUCTION: Enterococcal bloodstream infections have acquired considerable importance in recent years, mainly because of the increasing number of cases that occur during hospital admission. METHODS: Retrospective study of the clinical records of patients diagnosed with enterococcal bacteremia and hospitalized over a 12-year period (January 1994-April 2006), analyzing epidemiological, clinical and microbiological characteristics, outcome and prognostic factors. RESULTS: A total of 182 episodes of bacteremia were recorded; 68% of them were nosocomial infections, accounting for 5% of the in-hospital bacteremia episodes in this period. The most frequent sources of infection were urinary tract (29%), cardiovascular (25%), intra-abdominal (21%) and primary bacteremia (12%). Associated comorbid conditions were present in 85% of patients, mainly neoplasms (33%). Enterococcus faecalis was responsible for 70% of cases, E. faecium 22%, and other species of enterococci 8%. Twenty percent were polymicrobial bacteremia. Antibiotic resistance was documented in 23% of the strains: 14% ampicillin, 8% gentamicin, 3% ampicillin and gentamicin, and 0.5% vancomycin. Overall mortality was 31%. Polymicrobial bacteremia and comorbidity were associated with a poor prognosis. CONCLUSION: In our hospital, Enterococcus is the fifth most frequent cause of nosocomial bacteremia. E. faecium is characterized by a high incidence (more than 50% of cases) of ampicillin resistance.