Bacteriemias por staphylococcus aureus en el Hospital Clínico Universitario Virgen de la Arrixacaestudio epidemiológico, clínico y molecular

Résumé

The Staphylococcus aureus bacteremia (SAB) is a major infectious disease problem in both community-associated and nosocomial infections because of the development of complications such as mortality. Objectives: 1. Describe the characteristics, microbiological, and epidemiological characteristics of S. aureus bacteremia in our hospital. 2. To study the molecular epidemiology of bacteremic S. aureus strains and identify different clones and structure population. 3. Assess how clinically intervened and analyze the degree of compliance with interventions to improve in practice. 4. To study the evolution of each episode of bacteremia. Methods: The study was conducted at the Virgen de la Arrixaca University Hospital. Retrospectively included all episodes of S. aureus bacteremia occurred in the years 2012 and 2013. For each patient the clinical and epidemiological data were collected from a review of medical records. Microbiological data: Identification and sensitivity of each isolate. Molecular techniques: Detection of mecA gene by PCR; Detection of the gene encoding LPV; SCCmec typing, Spa-Typing and PFGE. Results: Microbiological and molecular research meticillin resistant S.aureus isolates (MRSA) In our series, patients with BSAMR account for 16%. 32.3% of all MRSA isolates were resistant to at least four or more antibiotics. All isolates were susceptible to vancomycin and teicoplanin. The phage typing showed a heterogeneous distribution, unable to establish groups. The most common SCCmec type was SCCmecIVc, (90.5%). An isolated IVh presented SCCmec subtype and another SCCmecV. The PGFE showed 12 different genotypes and the pulse-types being predominant were E7 and E8. An isolated pulse-type corresponded to A1; this strain showed PVL. Another isolated corresponded to genotype E13 (EMRSA15) (subtype SCCmecIVh). The spa-typing showed that spa-type t067 was the most frequent (42.8%). Microbiological and molecular study methicillin susceptible S. aureus strains (MSSA). Of the 110 SAMS 3.6% strains were sensitive to all antibiotics studied; 64.5% were resistant only to penicillin; They presented a pattern of multidrug resistance to three or more antibiotics 19% of the isolates. By Spa-Typing it found a clonal dispersion with 70 different spa-types. Of the 22 strains that PFGE was performed, and clinical molecular epidemiological link was found in two patients. Study of SAB in adult patients: This group of elderly population presented with significant comorbidity. Increased severity of comorbolidad group MRSAB respect to MSSA found. Most SAB hospital were related to purchase or healthcare. The most common infectious syndrome was catheter-related bacteremia (31.8%). A 32.11% of patients had one or more criteria complicated bacteremia. Having an MRSA bacteremia involves 3.2 times more risk of complicated bacteremia (CB). The overall mortality was 23.6%, although related mortality was 7.3%. MRSAB attributable mortality was 14.28% compared to 4.5% in MSSAB. Only 11.4% of the BSA receive proper treatment. Patients who meet more quality measures in the clinical management of infectious process are more cure rate and fewer complications. SAB in pediatric patients. The corresponding population group to the Children's Hospital is a 15.9%. 28.5% of pediatric patients had MRSAB . Of those acquired in the community (23.8%) was no BSAMR. The most common infectious syndrome was bacteremia of unknown origin (47.6%). 14.28% of patients have at least one criterion of complicated bacteremia. 18.8% received an appropriate empirical treatment. In child population in no case was fatal. 80% of patients are more compliant than 50% of global management measures of bacteremia. By studying how they influence all the measures taken in the management of patients the group meets less measures of income it has more days than the other groups.