Bacillus species pseudo-outbreak: construction works and collateral damage.

We describe the investigation and management of a pseudo-outbreak of Bacillus spp. bacteraemia associated with construction work in an emergency department (ED). During the pseudo-outbreak period 59 out of 3469 (1.7%) blood cultures yielded Bacillus spp. versus 24 out of 7628 (0.31%) in 2012. Material, surfaces, and air samples showed environmental contamination. Cases rapidly declined following the implementation of infection control measures and the end of construction. Construction works at the ED caused environmental contamination that most probably led to the pseudo-outbreak of Bacillus bacteraemia. In hospital settings, the lack of correctly implemented effective barriers during construction may place patients and healthcare providers at risk as well as lead to pseudo-outbreaks.

Bloodstream infections caused by Escherichia coli producing AmpC ß-lactamases: epidemiology and clinical features.

The aim of the study was to investigate the epidemiology and clinical features of bloodstream infections due to Escherichia coli producing AmpC ß-lactamases (AmpC-Ec-BSI). In a multi-centre case-control study, all third-generation-cephalosporin-resistant Escherichia coli BSI (3GC-Ec-BSI) isolates were analysed. Acquired bla AmpC (bla ac-AmpC) detection was done by polymerase chain reaction (PCR) and sequencing. Chromosomal bla AmpC (bla c-AmpC) expression was quantified by real-time PCR. Cases were patients with AmpC-Ec-BSI. Controls were patients with cephalosporin-susceptible E. coli BSI, matched 1:1 by sex and age. Demographics, comorbidities, intrinsic and extrinsic risk factors for antimicrobial resistance, clinical presentation and outcomes were investigated. Among 841 E. coli BSI, 17 were caused by AmpC-Ec (2 %). Eleven isolates (58.8 %) had bla ac-AmpC and six were bla c-AmpC overproducers. The mean age of cases was 66.2 years and 71 % were men. Cases were more frequently healthcare-related (82 vs. 52 % controls, p < 0.05) and presented more intrinsic and extrinsic risk factors. At least one risk factor was present in 94.1 % of cases vs. 41.7 % of controls (p = 0.002). Severity and length of stay (LOS) were higher among cases (mean Pitt Score 2.6 vs. 0.38 in controls, p = 0.03; LOS 17.5 days vs. 6 in controls, p = 0.02). Inappropriate empirical therapy (IET) was administered to 70.6 % of cases and 23.5 % of controls (p < 0.003). No differences were found in terms of cure rate at the 14th day and mortality. Bloodstream infections due to AmpC-Ec (mostly plasmid-mediated) are infrequent in our area. AmpC-Ec-BSI affects mainly patients with intrinsic risk factors and those with previous antibiotic exposure. A high proportion received IET.

CTX-M-15-H30Rx-ST131 subclone is one of the main causes of healthcare-associated ESBL-producing Escherichia coli bacteraemia of urinary origin in Spain.

OBJECTIVES: The objective of this study was to assess the prevalence and molecular epidemiology of ESBL-producing Escherichia coli causing healthcare-associated (HCA) and community-associated (CA) bacteraemia of urinary origin (BUO) in Spain. METHODS: An observational cohort study was conducted at eight hospitals from different Spanish geographical areas (2010-11). BUO episodes (n = 425) were classified as HCA (n = 215) and CA (n = 210), and one blood isolate per episode was collected. Susceptibility testing was performed, ESBLs were screened by double-disc diffusion test and ESBL and OXA-1 genes were characterized (PCR and sequencing). Population structure (phylogenetic groups, XbaI-PFGE and MLST) and ST131 subtyping (PCR) were determined. Virulence genes were detected by PCR and virulence score, profiles and extraintestinal pathogenic E. coli (ExPEC) status calculated. RESULTS: ESBL-producing E. coli prevalence was 9.2% (39/425). ESBL-producing E. coli episodes were significantly associated with HCA-BUO episodes [14% (30/215) versus 4.3% (9/210); P = 0.001]. The highest non-susceptibility proportions corresponded to ciprofloxacin (97.4%), amoxicillin/clavulanate (74.4%), co-trimoxazole (69.2%) and tobramycin (61.5%). Of the 39 ESBL-producing E. coli isolates, 34 produced CTX-M enzymes (21 CTX-M-15, 11 CTX-M-14 and 2 CTX-M-1). Fifteen STs were identified, the B2-ST131 clone being the most prevalent (54%; 21/39). All ST131 isolates were ExPEC and had the highest virulence scores, but they showed less diversity in virulence profiles than other STs. The H30Rx subclone accounted for most ST131 isolates (20/21), co-produced CTX-M-15 (20/20) and OXA-1 (19/20) enzymes and was associated with HCA episodes (16/20). CONCLUSIONS: The CTX-M-15-ST131-H30Rx subclone is a relevant MDR pathogen causing BUO, mainly HCA episodes. The dominance of this subclone with comparatively less diversity of virulence profiles reflects the spread of a successful and MDR ESBL ST131 lineage in Spain.

Bacteraemic pneumococcal pneumonia in COPD patients: better outcomes than expected.

The purpose of the study was to compare the clinical characteristics and outcomes of bacteraemic pneumococcal pneumonia (BPP) in chronic obstructive pulmonary disease (COPD) and non-COPD patients. A case-control study was conducted. Cases were any adult with BPP and forced expiratory volume in 1 second (FEV(1)) <80% and FEV(1)/forced expiratory vital capacity (FVC) <70%. Controls were patients with BPP without clinical diagnosis of COPD matched 1:2 by age, gender and date of isolation. Variables included co-morbidities, serotypes, pneumonia severity index (PSI), treatment and mortality. There were 45 cases and 90 controls. No significant differences were found in Charlson scores, antibiotic treatment, serotype distribution and severity. Malignancy, shock and mechanical ventilation were less frequent in COPD patients. One patient died vs 14 controls (p = 0.02). In univariate analysis, shock, multilobar involvement, Charlson score, heart failure and absence of COPD were associated with mortality. After adjustment for the presence of shock there were no differences in mortality. BPP presents less frequently with shock and has a lower mortality rate in COPD patients than in non-COPD patients.

Bloodstream infections in adults: importance of healthcare-associated infections.

OBJECTIVE: The objective of this study was to evaluate the characteristics of bloodstream infections occurring among outpatients having recent contact with the health care system compared to hospital and community-acquired infections. METHODS: Prospective observational cohort study of adult patients with bloodstream infections at three teaching hospitals. Bloodstream infection was defined as hospital-acquired if the first positive blood culture was performed more than 48 h after admission. Other bloodstream infections were classified as healthcare-associated or community-acquired. RESULTS: A total of 1157 episodes of bloodstream infections were studied; 581 (50.2%) were community-acquired, 295 (25.5%) were hospital-acquired, and 281 (24.3%) were health care-associated. Of the 281 health care-associated bloodstream infections, 68 (24%) occurred in patients residing in a nursing home, 104 (37%) in patients receiving intravenous therapy, health care at home, chemotherapy or attending dialysis, and 169 (60%) in patients hospitalized during the 90 days before their bloodstream infection (some patients belonged to more than one risk category). The highest prevalence rate of MRSA infections occurred in healthcare-associated infections (5%) (p<0.001). A significantly higher mortality rate was seen in the group with healthcare-associated infections (27.5%) than in community-acquired infections (10.4%) (p<0.001). CONCLUSIONS: Our results confirm that healthcare-associated bloodstream infections show important differences from community-acquired bloodstream infections and suggest that empirical antibiotic therapy should be similar to hospital-acquired bloodstream infections, taking into account the epidemiologic characteristics of each region.

Invasive pneumococcal disease among children in a health district of Barcelona: early impact of pneumococcal conjugate vaccine.

This study evaluated the impact of heptavalent pneumococcal conjugate vaccine (HPCV) on invasive pneumococcal disease (IPD) in children aged < or = 5 years in Barcelona, Spain. The incidence of IPD, vaccine uptake and prevalence of nasopharyngeal colonisation were analysed in two different periods: 1999-2001 (pre-licence period), and 2002-2004 (post-licence period). In total, 121 cases of IPD were identified. The overall incidence of IPD decreased from 96.9 cases/100,000 to 90.6 cases/100,000 (OR 0.93, 95% CI 0.69-1.26, p 0.71) between the two periods. The proportion of cases caused by non-vaccine-related serotypes (NVS) increased from 21% to 43.7% (OR 2.9, 95% CI 1.2-7, p 0.01). IPD was diagnosed in seven vaccinated children, six of whom were infected by NVS. There was a trend of diminishing prevalence of resistance to penicillin and macrolides in 2002-2004. The incidence of empyema increased from 1.7 to 8.5/100,000 (OR 4.5, 95% CI 0.91-18, p 0.06). The rate of vaccination ranged from 4.8% to 34%. It was concluded that the rates of IPD in this area did not decrease following the introduction of HPCV. The low uptake of vaccine and the greater proportion of colonisation/infection by NVS probably explain these findings. A trend of increasing empyema was also apparent. A decrease in the prevalence of penicillin and macrolide resistance paralleled the progressive uptake of vaccine.

Emergence and dissemination of quinolone-resistant Escherichia coli in the community.

We studied the evolution of resistance to quinolones in Escherichia coli from 1992 to 1997 in Barcelona, Spain. An increasing proportion of quinolone-resistant E. coli (QREC) infections was observed. QREC strains were more common in patients with nosocomial infections but also increased in patients with community-acquired infections (9% in 1992 to 17% in 1996). Seventy (12%) of 572 episodes of E. coli bacteremia were due to QREC. Factors significantly associated with QREC bacteremia were the presence of underlying disease, recent exposure to antibiotics, and bacteremia of unknown origin. In the multivariate analysis, only prior exposure to antimicrobial agents (P < 0.001; odds ratio [OR] = 2), specifically, to quinolones (P < 0. 001; OR = 14), and the presence of a urinary catheter (P < 0.001; OR = 2) were significantly associated with QREC bacteremia. Among 16 QREC isolates from cultures of blood of community origin selected at random, 13 different pulsed-field gel electrophoresis patterns were recognized, showing the genetic diversity of these isolates and in turn indicating the independent emergence of QREC in the community. The prevalence of QREC in the feces of healthy people was unexpectedly high (24% in adults and 26% in children). A survey of the prevalence of QREC of avian and porcine origin revealed a very high proportion of QREC in animal feces (up to 90% of chickens harbored QREC). The high prevalence of QREC in the stools of healthy humans in our area could be linked to the high prevalence of resistant isolates in poultry and pork.

Thoracic infection caused by Streptococcus milleri.

The objective of this study was to increase our understanding of the importance of members of the Streptococcus milleri (SM) group as respiratory pathogens, by studying the epidemiological and clinical features of thoracic infections caused by this group and comparing the epidemiology and prognosis of empyema caused by SM with cases of pneumococcal aetiology. The clinical histories and microbiology reports were reviewed in 27 cases of thoracic infection caused by SM over a period of 8 yrs. Cases of pneumococcal empyema that occurred during the same period were also analysed. Diagnoses were made of cases of empyema, including six with pneumonia and one with pulmonary abscess, three cases of pneumonia and two of mediastinitis. In 17 cases, SM was the only pathogen isolated. There was a history of instrument or surgical procedures on the digestive or respiratory tract in 59%. Secondary bacteraemia was documented in three cases. The treatment administered, a combination of antibiotics and surgery, was successful in 22 of 27 (81%) of cases. All strains were susceptible to penicillin. When the characteristics of the empyemas caused by monomicrobial SM infection were compared with those of pneumococcal aetiology from the same period of study, significant differences were found with respect to age, origin of the infection and the need for surgery. In conclusion, thoracic infections caused by Streptococcus milleri are largely pleural. They are polymicrobial in one-third of cases, commonly acquired in hospital and, in most patients, associated with major surgery and/or surgical procedures of the respiratory or digestive tract. The empyema frequently requires thoracotomy for complete resolution.

Urovirulence determinants in Escherichia coli strains causing prostatitis.

To define the urovirulence properties of Escherichia coli strains producing prostatitis, E. coli strains isolated from men with acute (7 strains) or chronic (23) prostatitis were compared with E. coli isolates from women with pyelonephritis (30), acute cystitis (60), or complicated urinary tract infection (UTI; 30). Strains from prostatitis patients were significantly more likely to express hemolysin than were strains causing complicated UTI (73% vs. 43%; P = .02) and more often demonstrated hybridization with the cytotoxic necrotizing factor-1 (CNF-1) probe (63%) than did strains from women (44%-48%). P fimbrial expression was highest among pyelonephritis (73%) and prostatitis strains (53%) and lowest among E. coli from women with complicated UTI (23%) and cystitis (30%; P < .05, prostatitis strains vs. either of the latter 2 groups). Results suggest that E. coli strains producing prostatitis generally possess urovirulence profiles similar to those of strains from women with acute uncomplicated pyelonephritis and that hemolysin and CNF-1 are especially prevalent in prostatitis strains.

Epidemiology of an unusually prolonged outbreak of typhoid fever in Terrassa, Spain.

An unusually prolonged outbreak of typhoid fever, from 1988 to 1994, in Terrassa (Barcelona, Spain), was caused by a casual food handler who was a carrier. The pattern of this outbreak suggested intermittent low-level exposure to Salmonella typhi. We found 70 patients with S. typhi infections, 52 of whom were available for study. Medical records were reviewed and patients were interviewed with use of a standard questionnaire. Phage typing and pulsed-field gel electrophoresis (PFGE) for strain subtyping were used to confirm the epidemiological data. The 27 outbreak strains shared the same phage type and the same PFGE pattern. Four sporadic strains shared the same phage type as the outbreak strain. PFGE was found to be useful for differentiating strains for epidemiological purposes.

Seven-year review of bacteremia caused by Streptococcus milleri and other viridans streptococci.

The Streptococcus milleri group is associated with a spectrum of serious suppurative infections that have not been well defined. The purposes of this study were to ascertain the clinical significance of Streptococcus milleri bacteremia and to determine the epidemiological, clinical, and microbiological features of these infections compared to those caused by other viridans streptococci. All cases of streptococcal bacteremia observed in a Spanish hospital in the period from January 1988 to December 1994 were reviewed. Of 137 cases of Streptococcus milleri infection, 33 (24%) were documented cases of bacteremia. Twenty-four patients were men (mean age 57.8 +/- 17.4 years). The majority of infections were abdominal in origin (20/33), the most frequent diagnoses being cholangitis/cholecystitis (18%) and appendicitis (12%). The origin of infection could not be established in three cases. Nine cases of bacteremia (27%) were polymicrobial. Six patients (18%) had septic shock; in four the infection was polymicrobial, and in two the infection was of abdominal origin. Eighteen of the 33 patients (54%) required surgery. Five patients died. All 33 Streptococcus milleri isolates were susceptible to penicillin. Twenty-two cases of bacteremia caused by other viridans streptococci were observed during the same period. There were no statistically significant differences between the two groups in terms of age, sex, mortality, rate of polymicrobial infection, rate of nosocomial acquisition of bacteremia, or the occurrence of shock. An abdominal origin of infection was more frequent in Streptococcus milleri bacteremia (p = 0.0001); a cardiovascular origin was more frequent in the viridans group (p = 0.01), as was a diagnosis of endocarditis (p = 0.004). Four patients with viridans streptococci bacteremia required surgery versus 18 patients with Streptococcus milleri bacteremia (p = 0.01). Viridans streptococci were notably less susceptible to penicillin (89%), clindamycin (79%), and erythromycin (79%).

[Fluoroquinolone and aminoglycoside resistance in chromosomal cephalosporinase-overproducing gram-negative bacilli strains with inducible beta-lactamase]. / Resistencia a fluorquinolonas y aminoglucósidos en cepas hiperproductoras de cefalosporinasa cromosómica de bacilos gramnegativos con betalactamasa inducible.

INTRODUCTION: The increasing prevalence of stable derepressed mutants over-producers of type I chromosomal cephalosporinase in inducible Enterobacteriaceae and Pseudomonas aeruginosa challenges the adequacy of third generation cephalosporins in the empirical treatment of certain nosocomial infections. We sought to determine the frequency of stable over-producers of type I enzyme and their associated resistance to fluoroquinolones and aminoglycosides. METHODS: Disc-diffusion and MIC determinations to extended-spectrum beta-lactams, imipenem, ciprofloxacin and gentamicin were performed in all cell isolates of inducible enteric bacteria (Enterobacter spp., Citrobacter spp., Serratia spp., Morganella morganii, Providencia spp.) and P. aeruginosa collected during the period of study (1992-1993). RESULTS: A total of 1,426 isolates of inducible enteric bacteria and P. aeruginosa were studied. Each one represented a single patient. Among the 511 isolates of enteric bacteria 15.1% of strains were found to be stable derepressed mutants (Serratia 2.2%; Morganella spp., 3%; Providencia and Proteus 3%; Citrobacter spp., 10%; Enterobacter spp., 23.6%); among the 916 P. aeruginosa isolates studied, 9.2% were stable over-producers. Among Citrobacter, Providencia and Proteus spp., 53.1% of stable over-producers were resistant to ciprofloxacin versus 20.2% of non-over-producers (p < 0.01); in P. aeruginosa, 35.3% of over-producers were resistant to gentamicin versus 25.0% in non-over-producers (p < 0.01). CONCLUSION: The prevalence of stable derepressed mutants is high among enteric bacteria and P. aeruginosa with type I inducible beta-lactamase. These strains frequently exhibit resistance to fluoroquinolones and aminoglycosides, reducing considerably the available therapeutic options.

[Pleural empyema caused by Legionella pneumophila]. / Empiema pleural por Legionella pneumophila.

Although pleural effusion is not uncommon in legionellosis, the development of empyema and the demonstration of the organism in pleural fluid are exceptional. We report four patients with pleural empyema with isolation of Legionella pneumophila in the pleural fluid culture. The patients were three males and one female, with ages ranging from 36 and 83 years. All had left pleuritic pain, fever and pleural effusion. The appearance of pleural effusion was purulent in two cases and serofibrinous in the other two. Initially, the diagnosis was only suspected in one patient. The other three received inadequate treatment, until the result of the culture of the pleural fluid in BCYE-alpha medium was known. After giving erythromycin therapy at high doses, the outcome was favorable in the four patients. It is concluded that, in the absence of another diagnosis, the presence of L. pneumophila should be systematically investigated in the pleural fluid although the disease is not clinically suspected.

[Type 1 fimbriae, P fimbriae and X adhesins in Escherichia strains causing pyelonephritis, cystitis and recurrent urinary infections]. / Fimbrias tipo 1, fimbrias P y adhesinas X, en cepas de Escherichia coli productoras de pielonefritis, cistitis e infecciones urinarias de repetición.

The presence of type 1 fimbriae, P fimbriae and X adhesins in 30 strains of Escherichia coli producing pyelonephritis, 30 strains producing cystitis, and 30 strains producing recurrent urinary infections are compared. All the strains were collected from adult women without risk factors for infections of the urinary tract. The presence of P fimbriae was 73% in strains producing pyelonephritis, 40% in strains producing cystitis and 20% in strains producing recurrent urinary infections; the presence of X adhesins was 3%, 0, and 17% respectively. There were, in consequence, significant differences between the groups studied; however, such differences were not observed with respect to the presence of type 1 fimbriae, which was 97%, 97% and 90%, respectively. We conclude that P fimbriae act as a factor of greater virulence in the strains of E. coli producing pyelonephritis and X adhesins are found almost exclusively in the strains producing recurrent urinary infections.