A systematic literature review and expert consensus on risk factors associated to infection progression in adult patients with respiratory tract or rectal colonisation by carbapenem-resistant Gram-negative bacteria.

OBJECTIVE: Risk factors (RFs) associated with infection progression in patients already colonised by carbapenem-resistant Gram-negative bacteria (CRGNB) have been addressed in few and disperse works. The aim of this study is to identify the relevant RFs associated to infection progression in patients with respiratory tract or rectal colonisation. METHODS: A systematic literature review was developed to identify RFs associated with infection progression in patients with CRGNB respiratory tract or rectal colonisation. Identified RFs were then evaluated and discussed by the expert panel to identify those that are relevant according to the evidence and expert's experience. RESULTS: A total of 8 articles were included for the CRGNB respiratory tract colonisation and 21 for CRGNB rectal colonisation, identifying 19 RFs associated with pneumonia development and 44 RFs associated with infection progression, respectively. After discussion, the experts agreed on 13 RFs to be associated with pneumonia development after respiratory tract CRGNB colonisation and 33 RFs to be associated with infection progression after rectal CRGNB colonisation. Respiratory tract and rectal colonisation, previous stay in the ICU and longer stay in the ICU were classified as relevant RF independently of the pathogen and site of colonisation. Previous exposure to antibiotic therapy or previous carbapenem use were also common relevant RF for patients with CRGNB respiratory tract and rectal colonisation. CONCLUSIONS: The results of this study may contribute to the early identification of CRGNB colonized patients at higher risk of infection development, favouring time-to-effective therapy and improving health outcomes.

[A systematic review and expert's analysis of risk factors of infections in adults due to carbapenem-resistant Pseudomonas aeruginosa or Acinetobacter baumannii in Spain]. / Revisión sistemática de la literatura y análisis de expertos sobre los factores de riesgo asociados a infecciones causadas por Pseudomonas aeruginosa o Acinetobacter baumannii resistentes a carbapenémicos en pacientes adultos en España.

OBJECTIVE: The aim of the study is to identify risk factors associated to infections caused by carbapenem-resistant Pseudomonas aeruginosa (CRPA) and carbapenem-resistant Acinetobacter baumannii (CRAB) in adult patients through a systematic literature review, classify them according to their importance and provide recommendations by experts in the Spanish context. METHODS: We developed a systematic literature review to identify risk factors associated to CRPA or CRAB infections and they were evaluated and discussed by a multidisciplinary panel of experts. RESULTS: There were included 29 studies for P. aeruginosa and 23 for A. baumannii out of 593 identified through systematic literature review. We identified 38 risk factors for P. aeruginosa and 36 for A. baumannii. After risk factor evaluation by the panel of experts, results for CRPA were: 11 important, 10 slightly important and 15 unimportant risk factors; and for CRAB were: 9 important, 5 slightly important and 19 unimportant risk factors. For both pathogens, previous use of antibiotics and hospitalization were important risk factors. CONCLUSIONS: We could identify the main risk factors associated to CRPA and CRAB through literature review. There is a need for developing additional studies with higher levels of evidence to identify sooner and better infected patients through associated risk factors.

Emerging non-13-valent pneumococcal conjugate vaccine (PCV13) serotypes causing adult invasive pneumococcal disease in the late-PCV13 period in Spain.

OBJECTIVE: An early reduction of adult invasive pneumococcal disease (IPD) was observed after the 13-valent pneumococcal conjugate vaccine (PCV13) introduction for children in Spain. We analysed the epidemiology of adult IPD in the late-PCV13 period. METHODS: This was a prospective multicentre study of adult IPD involving six hospitals. Strains were serotyped, genotyped and studied for antimicrobial susceptibility. The late-PCV13 period was compared with the pre- and early-PCV13 periods. RESULTS: A total of 2197 episodes were collected-949 in 2008-2009, 609 in 2012-2013 and 639 in 2015-2016. The initial decrease of IPD observed (from 12.3/100 000 to 8.1/100 000; 2008-2009 versus 2012-2013) plateaued in 2015-2016 (8.3/100 000). IPD due to PCV13 serotypes decreased (from 7.7 to 3.5 to 2.3/100 000; p < 0.05), whereas IPD caused by non-PCV13 serotypes increased (from 4.5 to 4.6 to 6.0/100 000; p < 0.05). The most frequent serotypes in the late-PCV13 period were: 8 (15.1%), 3 (10.5%), 12F (7.9%) and 9N (5.4%). These serotypes were related to major genotypes: CC53 (59.8%) and CC404 (30.4%) for serotype 8, CC180 (64.1%) and CC260 (28.1%) for serotype 3, CC989 (91.7%) for serotype 12F and CC67 (84.8%) for serotype 9N. Penicillin-non-susceptibility (21.2%) was associated with serotypes 11A (CC156), 14 (CC156) and 19A (CC320), and macrolide-resistance was related to serotypes 24F and 19A. Rates of pneumococcal meningitis remained stable throughout the periods (ranges 0.9, 0.8 and 1.0/100 000). CONCLUSIONS: The initial decrease of adult IPD observed after PCV13 introduction for children has been balanced by the rise of non-PCV13 serotypes. The spread of antibiotic-resistant lineages related to non-PCV13 serotypes (11A and 24F) could be a threat for the treatment of serious pneumococcal diseases.

Role of IncHI2 plasmids harbouring blaVIM-1, blaCTX-M-9, aac(6')-Ib and qnrA genes in the spread of multiresistant Enterobacter cloacae and Klebsiella pneumoniae strains in different units at Hospital Vall d'Hebron, Barcelona, Spain.

Seven Enterobacter cloacae isolates and seven Klebsiella pneumoniae isolates harbouring a phenotype compatible with the production of a metallo-ß-lactamase were recovered between 2009 and 2011 in three Intensive Care Units of Hospital Vall d'Hebron (Barcelona, Spain). The presence of bla(VIM), bla(IMP), bla(NDM), bla(CTX-M), aac(6')-Ib, qnrA, qnrB and qnrS genes was screened by polymerase chain reaction (PCR) and sequencing. Clonal relatedness of the isolates was assessed by pulsed-field gel electrophoresis (PFGE) and, in the case of K. pneumoniae isolates, by multilocus sequence typing (MLST). PCR-based replicon typing, Southern hybridisation, plasmid double-locus sequence typing and MOB relaxase classification methods were used to identify and characterise the plasmids carrying the resistance genes. Transferability of the identified plasmids was tested by conjugation assays. All 14 isolates were found to carry bla(VIM-1), bla(CTX-M-9) (except one isolate), aac(6')-Ib and qnrA genes. Clonality assessment demonstrated that E. cloacae isolates were distributed in three clonal clusters, whereas all of the K. pneumoniae isolates belonged to one unique clone, identified as sequence type ST252. All studied isolates harboured a large conjugative IncHI2 MOB(H11) plasmid carrying all of the detected resistance genes. Plasmid DNA analysis showed that all of them belonged to the ST1 IncHI2 plasmid cluster and shared the same relaxase partial sequence. In conclusion, the present study describes the dissemination within a hospital of multiresistant E. cloacae and K. pneumoniae isolates producing VIM-1. A complex clonal epidemiology of the E. cloacae isolates was observed and plasmid DNA analysis strongly supports horizontal exchanges of the same IncHI2 plasmid between different strains and species.

[Isolation precautions in a tertiary paediatric hospital]. / Precauciones de aislamiento en un hospital pediátrico de tercer nivel.

INTRODUCTION: Isolation is one of the measures to prevent the spread of nosocomial infections. However, in children's hospitals, given the type of patients and infections, and the architectural features of hospital wards, isolation precautions are sometimes difficult to implement and enforce. MATERIAL AND METHODS: An observational, descriptive study was conducted on the isolation precautions taken at the Children's Hospital Vall d'Hebron in Barcelona, from January to December, 2007. The isolation precautions applied were those of the Centers for Disease Control and Prevention from the USA, and those of the Department of Health of the Generalitat de Cataluña. RESULTS: Of the patients admitted during the study period, 5.4% needed isolation. The General Paediatrics ward generated the highest number of isolations (10.7%). The most frequently microorganisms needing isolation precautions were respiratory syncytial virus and rotavirus. Contact precautions was the type of isolation most applied (90% of isolations). The Neonatal Intensive Care Unit and the Paediatric Oncology and Haematology Service were the areas with a greater number of patients isolated due to infection or colonization by multiresistant bacteria (48% and 67% of the isolations, respectively). CONCLUSIONS: The implementation of a surveillance and infection control program is essential to reduce the rate of hospital-acquired infections. Knowledge of the frequency of isolated patients at each centre and the availability of resources for the correct application of isolation precautions are fundamental for these goals to be achieved.

Influence of media and testing methodology on susceptibility to tigecycline of Enterobacteriaceae with reported high tigecycline MIC.

The tigecycline susceptibility of six different Enterobacteriaceae strains with reported high tigecycline MICs was determined in quintuplicate by four methodologies using Mueller-Hinton agar and broth from six manufacturers. The MICs determined by Etest were a >or=1-fold dilution lower than those determined by broth microdilution and agar dilution, with the highest modal values given by agar dilution. The highest modal MICs were obtained using Oxoid medium, and the lowest inhibition zone values (disc diffusion) were obtained using Oxoid and bioMérieux media. The lowest MICs were obtained by Etest using Difco or Merck media.

Osteomyelitis of the jaw: resistance to clindamycin in patients with prior antibiotics exposure.

The purpose of this paper was to review our clinical experience in patients with osteomyelitis (OM) of the jaw, focusing on aspects of antimicrobial resistance. A retrospective review of the medical records of adult patients with jaw OM was carried out. Among 46 cases of jaw OM, the cause was odontogenic in 32 (seven had recent dental implants and four bisphosphonate osteonecrosis), postoperative/post-traumatic in eight, and secondary to osteoradionecrosis in six. Clinical features were chronic in 91.3%. The infection was polymicrobial in 24/41 (65.9%). Viridans streptococci were the most commonly isolated agents. Among 26 viridans streptococci tested, 81% were susceptible to penicillin and 96% to fluorquinolones, but only 11.5% to clindamycin. Overall, 35/38 (92.1%) had at least one clindamycin-resistant isolate. Appropriate antibiotics were administered for a mean of 5.8 +/- 3.2 months. Beta-lactams were used in 19 cases and fluorquinolones in 14. Among 39 cases with long-term follow-up, only two relapsed. Currently, jaw OM is commonly related to osteoradionecrosis, dental implants, and bisphosphonates. In patients with prior antibiotics exposure, a high percentage of infections were caused by clindamycin-resistant microorganisms, thus, beta-lactams should be the antibiotic of choice. In penicillin-allergic cases, the new fluorquinolones, probably in combination with rifampin and/or clindamycin, could be a promising alternative.

Management of catheter-related Staphylococcus aureus bacteremia: when may sonographic study be unnecessary?

This study reviews the outcome of patients with uncomplicated catheter-related Staphylococcus aureus bacteremia diagnosed in our hospital from January 1997 to December 1999 and treated with short-course antibiotic therapy. Our aim was to assess the effectiveness of this regimen for minimizing complications (relapses, endocarditis and metastatic foci). A total of 213 episodes of bacteremia were registered and 167 (78.4%) were nosocomial. Among these, 87 (52.1%) were catheter-related Staphylococcus aureus bacteremia and 20 were primary nosocomial bacteremia. Endocarditis was diagnosed during the acute episode in 7/107 of these patients (2 by persistent fever after catheter removal and 5 by metastatic foci; 3 of them also had cardiac risk factors) and confirmed with transesophageal echocardiography. Among the 84/87 catheter-related Staphylococcus aureus bacteremia and 16/20 primary nosocomial bacteremia patients who did not develop endocarditis, 31 patients died during the acute episode (16 due to sepsis despite initiation of antibiotic treatment and 15 due to the underlying disease) and five had osteoarticular foci. The remaining 64 episodes were considered to be uncomplicated bacteremia (no cardiac risk factors, persistent fever, metastatic foci, or clinical signs of endocarditis) and were treated with 10-14 days of high-dose antistaphylococcal antibiotics. Echocardiography was not mandatory in these patients. Of the 64 uncomplicated episodes, 62 were followed for at least 3 months and none relapsed or developed endocarditis. Even though some of the patients might have had subclinical endocarditis, short-course therapy with high doses of antistaphylococcal antibiotics was effective for treating uncomplicated catheter-related Staphylococcus aureus bacteremia. Transesophageal echocardiography may not be necessary in these cases.