Executive summary: Guidelines for the diagnosis and treatment of septic arthritis in adults and children, developed by the GEIO (SEIMC), SEIP and SECOT.

Infection of a native joint, commonly referred to as septic arthritis, is a medical emergency because of the risk of joint destruction and subsequent sequelae. Its diagnosis requires a high level of suspicion. These guidelines for the diagnosis and treatment of septic arthritis in children and adults are intended for use by any physician caring for patients with suspected or confirmed septic arthritis. They have been developed by a multidisciplinary panel with representatives from the Bone and Joint Infections Study Group (GEIO) belonging to the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), the Spanish Society of Paediatric Infections (SEIP) and the Spanish Society of Orthopaedic Surgery and Traumatology (SECOT), and two rheumatologists. The recommendations are based on evidence derived from a systematic literature review and, failing that, on the opinion of the experts who prepared these guidelines. A detailed description of the background, methods, summary of evidence, the rationale supporting each recommendation, and gaps in knowledge can be found online in the complete document.

Osteosynthesis-associated infection of the lower limbs by multidrug-resistant and extensively drug-resistant Gram-negative bacteria: a multicentre cohort study.

Purpose: The purpose of this study was the clinical and therapeutic assessment of lower-limb osteosynthesis-associated infection (OAI) by multidrug-resistant (MDR) and extensively drug-resistant (XDR) Gram-negative bacteria (GNB), which have been poorly studied to date. Methods: A prospective multicentre observational study was conducted on behalf of ESGIAI (the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group on Implant-Associated Infections). Factors associated with remission of the infection were evaluated by multivariate and Cox regression analysis for a 24-month follow-up period. Results: Patients ( n = 57 ) had a history of trauma (87.7 %), tumour resection (7 %) and other bone lesions (5.3 %). Pathogens included Escherichia coli ( n = 16 ), Pseudomonas aeruginosa ( n = 14 ; XDR 50 %), Klebsiella spp. ( n = 7 ), Enterobacter spp. ( n = 9 ), Acinetobacter spp. ( n = 5 ), Proteus mirabilis ( n = 3 ), Serratia marcescens ( n = 2 ) and Stenotrophomonas maltophilia ( n = 1 ). The prevalence of ESBL (extended-spectrum ß -lactamase), fluoroquinolone and carbapenem resistance were 71.9 %, 59.6 % and 17.5 % respectively. Most patients ( n = 37 ; 64.9 %) were treated with a combination including carbapenems ( n = 32 ) and colistin ( n = 11 ) for a mean of 63.3 d. Implant retention with debridement occurred in early OAI (66.7 %), whereas the infected device was removed in late OAI (70.4 %) ( p = 0.008 ). OAI remission was achieved in 29 cases (50.9 %). The type of surgery, antimicrobial resistance and duration of treatment did not significantly influence the outcome. Independent predictors of the failure to eradicate OAI were age > 60  years (hazard ratio, HR, of 3.875; 95 % confidence interval, CI95 %, of 1.540-9.752; p = 0.004 ) and multiple surgeries for OAI (HR of 2.822; CI95 % of 1.144-6.963; p = 0.024 ). Conclusions: Only half of the MDR/XDR GNB OAI cases treated by antimicrobials and surgery had a successful outcome. Advanced age and multiple surgeries hampered the eradication of OAI. Optimal therapeutic options remain a challenge.

Implant Removal in the Management of Prosthetic Joint Infection by Staphylococcus aureus: Outcome and Predictors of Failure in a Large Retrospective Multicenter Study.

OBJECTIVES: To compare the characteristics and outcomes of cases with acute prosthetic joint infection (PJI; early post-surgical or hematogenous) by Staphylococcus aureus managed with implant removal (IRm) or debridement and retention (DAIR). To analyze the outcomes of all cases managed with IRm (initially or after DAIR failure). METHODS: Retrospective, multicenter, cohort study of PJI by S. aureus (2003-2010). Overall failure included mortality within 60 days since surgery and local failure due to staphylococcal persistence/relapse. RESULTS: 499 cases, 338 initially managed with DAIR, 161 with IRm. Mortality was higher in acute PJI managed initially with IRm compared to DAIR, but not associated with the surgical procedure, after propensity score matching. Underlying conditions, hemiarthroplasty, and methicillin-resistant S. aureus were risk factors for mortality. Finally, 249 cases underwent IRm (88 after DAIR failure); overall failure was 15.6%. Local failure (9.3%) was slightly higher in cases with several comorbidities, but independent of previous DAIR, type of IRm, and rifampin treatment. CONCLUSIONS: In a large multicenter study of S. aureus PJI managed with IRm, failure was low, but mortality significant, especially in cases with acute PJI and underlying conditions, but not associated with the IRm itself. Rifampin efficacy was limited in this setting.

Infections after spine instrumentation: effectiveness of short antibiotic treatment in a large multicentre cohort.

BACKGROUND AND OBJECTIVES: Available information about infection after spine instrumentation (IASI) and its management are scarce. We aimed to analyse DAIR (debridement, antibiotics and implant retention) prognosis and evaluate effectiveness of short antibiotic courses on early forms. METHODS: Multicentre retrospective study of patients with IASI managed surgically (January 2010-December 2016). Risk factors for failure were analysed by multivariate Cox regression and differences between short and long antibiotic treatment were evaluated with a propensity score-matched analysis. RESULTS: Of the 411 IASI cases, 300 (73%) presented in the first month after surgery, 48 in the second month, 22 in the third and 41 thereafter. Infections within the first 2 months (early cases) occurred mainly to older patients, with local inflammatory signs and predominance of Enterobacteriaceae, unlike those in the later periods. When managed with DAIR, prognosis of early cases was better than later ones (failure rate 10.4% versus 26.1%, respectively; P = 0.02). Risk factors for DAIR failure in early cases were female sex, Charlson Score, large fusions (>6 levels) and polymicrobial infections (adjusted HRs of 2.4, 1.3, 2.6 and 2.26, respectively). Propensity score matching proved shorter courses of antibiotics (4-6 weeks) as effective as longer courses (failure rates 11.4% and 10.5%, respectively; P = 0.870). CONCLUSIONS: IASIs within the first 2 months could be managed effectively with DAIR and shorter antibiotic courses. Clinicians should be cautious when faced with patients with comorbidities, large fusions and/or polymicrobial infections.

Clinical Use of Colistin in Biofilm-Associated Infections.

Biofilm is an adaptive bacterial strategy whereby microorganisms become encased in a complex glycoproteic matrix. The low concentration of oxygen and nutrients in this environment leads to heterogeneous phenotypic changes in the bacteria, with antimicrobial tolerance being of paramount importance. As with other antibiotics, the activity of colistin is impaired by biofilm-embedded bacteria. Therefore, the recommendation for administering high doses in combination with a second drug, indicated for planktonic infections, remains valid in this setting. Notably, colistin has activity against metabolically inactive biofilm-embedded cells located in the inner layers of the biofilm structure. This is opposite and complementary to the activity of other antimicrobials that are able to kill metabolically active cells in the outer layers of the biofilm. Several experimental models have shown a higher activity of colistin when used in combination with other agents, and have reported that this can avoid the emergence of colistin-resistant subpopulations. Most experience of colistin in biofilm-associated infections comes from patients with cystic fibrosis, where the use of nebulized colistin allows high concentrations to reach the site of the infection. However, limited clinical experience is available in other scenarios, such as osteoarticular infections or device-related central nervous system infections caused by multi-drug resistant microorganisms. In the latter scenario, the use of intraventricular or intrathecal colistin also permits high local concentrations and good clinical results. Overall, the efficacy of intravenous colistin seems to be poor, but its association with a second antimicrobial significantly increases the response rate. Given its activity against inner bioflm-embedded cells, its possible role in combination with other antibiotics, beyond last-line therapy situations, should be further explored.

The Different Microbial Etiology of Prosthetic Joint Infections according to Route of Acquisition and Time after Prosthesis Implantation, Including the Role of Multidrug-Resistant Organisms.

The aim of our study was to characterize the etiology of prosthetic joint infections (PJIs)-including multidrug-resistant organisms (MDRO)-by category of infection. A multicenter study of 2544 patients with PJIs was performed. We analyzed the causative microorganisms according to the Tsukayama's scheme (early postoperative, late chronic, and acute hematogenous infections (EPI, LCI, AHI) and "positive intraoperative cultures" (PIC)). Non-hematogenous PJIs were also evaluated according to time since surgery: <1 month, 2-3 months, 4-12 months, >12 months. AHIs were mostly caused by Staphylococcus aureus (39.2%) and streptococci (30.2%). EPIs were characterized by a preponderance of virulent microorganisms (S. aureus, Gram-negative bacilli (GNB), enterococci), MDROs (24%) and polymicrobial infections (27.4%). Conversely, coagulase-negative staphylococci (CoNS) and Cutibacterium species were predominant in LCIs (54.5% and 6.1%, respectively) and PICs (57.1% and 15.1%). The percentage of MDROs isolated in EPIs was more than three times the percentage isolated in LCIs (7.8%) and more than twice the proportion found in AHI (10.9%). There was a significant decreasing linear trend over the four time intervals post-surgery for virulent microorganisms, MDROs, and polymicrobial infections, and a rising trend for CoNS, streptococci and Cutibacterium spp. The observed differences have important implications for the empirical antimicrobial treatment of PJIs.

Multidrug-resistant and extensively drug-resistant Gram-negative prosthetic joint infections: Role of surgery and impact of colistin administration.

Factors influencing treatment outcome of patients with Gram-negative bacterial (GNB) multidrug-resistant (MDR) and extensively drug-resistant (XDR) prosthetic joint infection (PJIs) were analysed. Data were collected (2000-2015) by 18 centres. Treatment success was analysed by surgery type for PJI, resistance (MDR/XDR) and antimicrobials (colistin/non-colistin) using logistic regression and survival analyses. A total of 131 patients (mean age 73.0 years, 35.9% male, 58.8% with co-morbidities) with MDR (n = 108) or XDR (n = 23) GNB PJI were assessed. The most common pathogens were Escherichia coli (33.6%), Pseudomonas aeruginosa (25.2%), Klebsiella pneumoniae (21.4%) and Enterobacter cloacae (17.6%). Pseudomonas aeruginosa predominated in XDR cases. Isolates were carbapenem-resistant (n = 12), fluoroquinolone-resistant (n = 63) and ESBL-producers (n = 94). Treatment outcome was worse in XDR versus MDR cases (P = 0.018). Success rates did not differ for colistin versus non-colistin in XDR cases (P = 0.657), but colistin was less successful in MDR cases (P = 0.018). Debridement, antibiotics and implant retention (DAIR) (n = 67) was associated with higher failure rates versus non-DAIR (n = 64) (OR = 3.57, 95% CI 1.68-7.58; P < 0.001). Superiority of non-DAIR was confirmed by Kaplan-Meir analysis (HR = 0.36, 95% CI 0.20-0.67) and remained unchangeable by time of infection (early/late), antimicrobial resistance (MDR/XDR) and antimicrobials (colistin/non-colistin) (Breslow-Day, P = 0.737). DAIR is associated with higher failure rates even in early MDR/XDR GNB PJIs versus implant removal. Colistin should be preserved for XDR cases as it is detrimental in MDR infections.

Analysis of mortality in a cohort of 650 cases of bacteremic osteoarticular infections.

OBJECTIVES: The mortality of patients with bacteremic osteoarticular infections (B-OAIs) is poorly understood. Whether certain types of OAIs carry higher mortality or interventions like surgical debridement can improve prognosis, are unclarified questions. METHODS: Retrospective analysis of a prospective cohort of patients with B-OAIs treated at a teaching hospital in Barcelona (1985-2014), analyzing mortality (30-day case-fatality rate). B-OAIs were categorized as peripheral septic arthritis or other OAIs. Factors influencing mortality were analyzed using logistic regression models. The association of surgical debridement with mortality in patients with peripheral septic arthritis was evaluated with a multivariate logistic regression model and a propensity score matching analysis. RESULTS: Among 650 cases of B-OAIs, mortality was 12.2% (41.8% of deaths within 7 days). Compared with other B-OAI, cases of peripheral septic arthritis were associated with higher mortality (18.6% vs 8.3%, p < 0.001). In a multiple logistic regression model, peripheral septic arthritis was an independent predictor of mortality (adjusted odds ratio [OR] 2.12; 95% CI: 1.22-3.69; p = 0.008). Cases with peripheral septic arthritis managed with surgical debridement had lower mortality than those managed without surgery (14.7% vs 33.3%; p = 0.003). Surgical debridement was associated with reduced mortality after adjusting for covariates (adjusted OR 0.23; 95% CI: 0.09-0.57; p = 0.002) and in the propensity score matching analysis (OR 0.81; 95% CI: 0.68-0.96; p = 0.014). CONCLUSIONS: Among patients with B-OAIs, mortality was greater in those with peripheral septic arthritis. Surgical debridement was associated with decreased mortality in cases of peripheral septic arthritis.

Understanding the acute inflammatory response to Pseudomonas aeruginosa infection: differences between susceptible and multidrug-resistant strains in a mouse peritonitis model.

The increasing emergence of multidrug-resistant (MDR) Pseudomonas aeruginosa strains is associated with the spread of a few international epidemic clones called high-risk clones. The existence of a fitness cost associated with multidrug resistance remains unclear, and little is known about the host inflammatory response in acute P. aeruginosa infections. This study aimed to investigate how the inflammatory response occurs in the most relevant high-risk clones and to compare the process with that recorded in clinical susceptible isolates. Nine P. aeruginosa strains were studied, including the most relevant MDR high-risk clones (ST111, ST175 and ST235) circulating worldwide. The inflammatory response in terms of the release of interleukins in serum was investigated in a mouse peritonitis-sepsis model at three time points (4, 8 and 12 h). TNFα and interleukin-10 (IL-10) levels were significantly higher at all time points in mice inoculated with clinical susceptible strains compared with those inoculated with MDR strains. IL-6 levels were significantly higher in the clinical susceptible strain group at 8 h and 12 h (P = 0.036 and P = 0.007, respectively). Bacterial counts (log CFU/mL) in peritoneal fluid were higher in the clinical susceptible strain group compared with the MDR strain group at 8 h [6.00 (4.30-6.90) vs. 4.46 (3.30-5.34); P = 0.005] and 12 h [7.75 (4.00-7.97) vs. 4.04 (2.58-4.94); P = 0.003]. MDR P. aeruginosa strains elicited a weaker inflammatory response than susceptible strains in an experimental mouse model, suggesting the existence of a fitness cost associated with multidrug resistance.

Acute Inflammatory Response of Patients with Pseudomonas aeruginosa Infections: A Prospective Study.

The severity of Pseudomonas aeruginosa (PA) infection may be determined by the interaction with the host immune system. We designed a prospective study to assess the relationship between the inflammatory response and the clinical presentation and outcome of PA infection. We also investigated whether there are differences in the inflammatory response depending on the resistance profile of PA. Interleukin-6 (IL-6), IL-10, procalcitonin (PCT), and C-reactive protein (CRP) were measured. Sixty-nine infection episodes were recorded; 40 caused by non-multidrug-resistant (non-MDR) strains [29 (73%) respiratory; 8 (20%) bacteremia], 12 by MDR non-extensively drug-resistant (MDR-non-XDR) [9 (75%) respiratory; 3 (25%) bacteremia], and 17 by XDR strains [9 (53%) respiratory; 7 (41%) bacteremia]. All inflammatory parameters were significantly higher in patients who developed acute organ dysfunction and bacteremia. PCT levels were higher in patients with early mortality [p = 0.050]. Inflammatory biomarkers were higher in patients with XDR than in those with non-MDR PA [IL-6 430 (67-951) vs. 77 (34-216), p = 0.02; IL-10 3.3 (1.5-16.3) vs. 1.3 (0-3.9), p = 0.02; and PCT 1.1 (0.6-5.2) vs. 0.3 (0.1-1.0), p = 0.008]. The intensity of inflammatory response was associated with the severity of PA infection, particularly if bacteremia occurred. Only PCT was documented useful to predict the outcome. XDR infections presented a higher inflammatory response; related in part to the larger number of bloodstream infections in this group.

Peak early diastolic mitral annulus velocity by tissue Doppler imaging for the assessment of left ventricular relaxation in subjects with mitral annulus calcification.

AIMS: The aim of this article was to determine whether lateral and septal early diastolic mitral annular velocities (LW-e' and IS-e', respectively) accuracy to reflect left ventricular (LV) relaxation is truly compromised by a limitation of mitral annular motion due to mitral annulus calcification (MAC) and to search for e' surrogates to circumvent this limitation. METHODS AND RESULTS: LW-e', IS-e', and peak early diastolic velocities at the basal-lateral and basal-septal LV segments 2 cm distal to the annulus (LW-e'2 and IS-e'2, respectively) were measured using tissue Doppler imaging (TDI) in 206 consecutive patients referred for echocardiography. Significant MAC (assessed by two-dimensional echocardiography) was present in 57 (28%) subjects. There was a significant reduction in LW-Δe' (LW-e' minus LW-e'2) in subjects with posterior MAC (0.15 ± 1.35 vs. 1.30 ± 1.24 cm/s, P < 0.0001) and a small but not significant reduction in IS-Δe' (IS-e' minus IS-e'2) in subjects with anterior MAC (-0.15 ± 1.04 vs. 0.42 ± 1.56 cm/s, P = 0.07), compared with age-matched no MAC subjects. Potential confusion factors were analysed on multiple regression. The basal segments in which e'2 were measured were free of calcification regardless of MAC. In search for e'2-based surrogates for e', the regression equation [Formula: see text] (R(2) = 0.86, P < 0.0001) was obtained from the first 100 consecutive subjects and validated in the next 49 no MAC subjects (intraclass correlation coefficient 0.96, P < 0.0001). In the septal side, no difference was found between IS-e' and IS-e'2 in the 149 subjects with no MAC (8.5 ± 3.1 vs. 8.5 ± 2.9 cm/s, P = 0.55). CONCLUSION: MAC significantly affected LW-e' (and not significantly IS-e') accuracy to reflect LV relaxation. [Formula: see text] and IS-e'2 as surrogates for LW-e' and IS-e', respectively, may correct this inaccuracy.

Changing trends in the epidemiology of pyogenic vertebral osteomyelitis: the impact of cases with no microbiologic diagnosis.

OBJECTIVES: The observed higher incidence of pyogenic vertebral osteomyelitis (PVO) may entail an increasing number of patients with no microbiologic diagnosis. The true incidence of these cases, how exhaustive the etiologic diagnostic efforts must be, and the usefulness of an empirical antibiotic therapy are not well defined. METHODS: Retrospective analysis of all cases of vertebral osteomyelitis in our center (1991-2009) and retrospective analysis of cases of PVO (2005-2009). Clinical data, diagnostic procedures, treatment, and outcome were reviewed. A comparative analysis between microbiologically confirmed PVO (MCPVO) and probable PVO (PPVO) was performed. RESULTS: Increasing incidence of PVO (+0.047 episodes/100,000 inhabitants-year). During the last decade, there was an increase of PPVO (+0.059 episodes/100,000 inhabitants-year) with stable incidence of MCPVO. During 2005-2009, there were 72 patients [47 (65%) MCPVO and 25 (35%) PPVO]. 60% men; mean age was 66 years. Bacteremia was found in 59%. Computed tomographic guided vertebral biopsy, positive in 7/36 (19%), was more successful among patients with bacteremia. Among MCPVO, there was an increasing proportion of less virulent bacteria. Cases of MCPVO presented more frequently with sepsis, fever, and high acute-phase reactants, and PPVO cases were mostly treated with oral fluoroquinolones plus rifampin. No differences were found between both groups in outcome (93% success, 22% sequelae). CONCLUSIONS: An epidemiologic change of PVO is suggested by a higher incidence of PPVO and the isolation of less virulent microorganisms among MCPVO. In this setting, the availability of an oral and effective empirical antibiotic therapy may challenge an exhaustive prosecution of the etiology.

Clinical outcome and microbiological findings using antibiotic-loaded spacers in two-stage revision of prosthetic joint infections.

OBJECTIVES: Antibiotic-loaded spacers may improve antimicrobial efficacy in two-stage revision of prosthetic joint infections, but they may also interfere in the course of infection. This prospective study of prosthetic joint infections managed with two-stage revision and antibiotic-loaded spacers (2004-09) analyzes case outcomes and proposes a second-stage culture interpretation scheme. METHODS: Second-stage infection was diagnosed upon second-stage cultures (synovial membranes, joint fluid, spacers), as either superinfection (≥2 samples, new organism) or persistence (≥1 samples, previously isolated organism). Isolated positive antibiotic-loaded spacers cultures were considered as colonizations. RESULTS: Of 42 patients, two had two prosthetic infections (n = 44): 25 knees, 19 hips. Spacers contained gentamicin (33), vancomycin (10) and aztreonam (1). Three patients (7%) with wound healing impairment required debridement and spacer exchange. The remainder underwent second-stage surgery as planned: 34 (77%) new arthroplasties, five arthrodeses, one resection arthroplasty and one permanent spacer. Of 18 cases (44%) with ≥1 positive sample, only four (10%) were second-stage infections. Fourteen antibiotic-loaded spacers cultures (34%) were positive. Four new prostheses (9%) supervened further infections: one by the organism isolated in the spacer, three by new bacteria. CONCLUSIONS: The findings of second-stage cultures show that the surgical site is frequently non-sterile at reimplantation. Isolated positive antibiotic-loaded spacer cultures usually have no clinical consequences, but together with tissue cultures they help to diagnose second-stage infections when clinical signs are absent.

Community-acquired bacterial meningitis in elderly patients: experience over 30 years.

Clinical characteristics, etiologies, evolution, and prognostic factors of community-acquired bacterial meningitis in elderly patients are not well known. To improve this knowledge, all episodes of community-acquired bacterial meningitis were prospectively recorded and cases occurring in patients >or=65 years old were selected. During the period 1977-2006, 675 episodes in adults (aged >or=18 yr) were recorded, with 185 (27%) in patients aged >or=65 years old; 76 were male and 109 were female, with a mean age of 73 +/- 6 years (range, 65-93 yr). Causative microorganisms were Streptococcus pneumoniae 74, Neisseria meningitidis 49, Listeria monocytogenes 17, other streptococcal 9, Escherichia coli 6, Haemophilus influenzae 4, Klebsiella pneumoniae and Staphylococcus aureus 2 each, Capnocytophaga canimorsus and Enterococcus faecalis 1 each, and unknown in 20. On admission 91% had had fever, 32% were in a coma (Glasgow Coma Scale or=65 yr), who showed a higher frequency of diabetes and malignancy as underlying disease; pneumonia, otitis, and pericranial fistula as predisposing factors; and S. pneumoniae and L. monocytogenes as etiology. There were also differences in clinical presentation, complications, sequelae, and mortality. Factors independently related with mortality were age, pneumonia as a predisposing factor, coma on admission, and heart failure and seizures after therapy. Dexamethasone therapy was a protective factor. In conclusion, bacterial meningitis in elderly patients is associated with greater diagnostic difficulties and neurologic severity and more complications, as well as with increased mortality. Antiseizure prophylaxis might be useful in these patients.

[Orthopedic device-related infections]. / Infecciones relacionadas con las prótesis articulares.

Prosthetic joint infection is an increasing public health problem. The bacterial biofilms that form on these foreign bodies are resistant to host defence mechanisms and antimicrobial therapy. Sixty per cent of prosthetic joint infections are caused by Staphylococcus sp., and they are usually acquired during surgery or in the early post-operative period, but can also occur by haematogenous seeding. There are several kinds of prosthetic joint infections: early postoperative infection (EPI), late postoperative infection (LPI), haematogenous infection (HI), and positive operative cultures. In EPI and HI, early diagnosis is mandatory to save the implant, and in LPI the main issue is the differential diagnosis with aseptic loosening. The treatment of choice for susceptible staphylococcal EPI and HI is debridement and a combination of rifampin and levofloxacin for 8 weeks, with retention of the implant. In LPI, replacement of the prosthesis is required, followed by antibiotic therapy for 6 weeks.

Nosocomial outbreak due to extended-spectrum-beta-lactamase- producing Enterobacter cloacae in a cardiothoracic intensive care unit.

Enterobacter cloacae has been associated with several outbreaks, usually involving strains that overproduce chromosomal beta-lactamase or, uncommonly, strains expressing extended-spectrum beta-lactamases (ESBL). Only sporadic cases of ESBL-producing E. cloacae have been identified in our hospital in recent years. We describe the epidemiology and clinical and microbiological characteristics of an outbreak caused by ESBL-producing E. cloacae in a cardiothoracic intensive care unit (CT-ICU). Prospective surveillance of patients with infection or colonization by ESBL-producing E. cloacae among patients admitted to the CT-ICU was performed during the outbreak. Production of ESBL was determined by decreased susceptibility to expanded-spectrum cephalosporins and a positive double-disk test result. Clone relatedness was determined by pulsed-field gel electrophoresis (PFGE). From July to September 2005, seven patients in the CT-ICU with ESBL-producing E. cloacae were identified (four males; median age, 73 years; range, 45 to 76 years); six patients had cardiac surgery. Four patients developed infections; three had primary bacteremia, one had ventilator-associated pneumonia, and one had tracheobronchitis. ESBL-producing E. cloacae showed resistance to quinolones and aminoglycosides. PFGE revealed two patterns. Five isolates belonged to clone A; two carried a single ESBL (pI 8.2 and a positive PCR result for the SHV type), and three carried two ESBLs (pIs 8.1 and 8.2 and positive PCR results for the SHV and CTX-M-9 types). Isolates belonging to clone B carried a single ESBL (pI 5.4 and a positive PCR result for the TEM type). Review of antibiotic consumption showed increased use of cefepime and quinolones during June and July 2005. The outbreak was stopped by the implementation of barrier measures and cephalosporin restriction. ESBL production could be increasingly common in nosocomial pathogens other than Escherichia coli or Klebsiella pneumoniae.

Spontaneous pyogenic facet joint infection.

OBJECTIVE: To analyze the clinical features, approaches to management, and outcome of spontaneous pyogenic facet joint infection (PFJI) in adults. PATIENTS AND METHODS: Case series of 10 adults with microbiologically proven PFJI diagnosed during a 10-year period in a teaching hospital, plus a review of 32 additional cases previously reported (PubMed 1972 to 2003). Patients with prior spinal instrumentation or surgery and injection drug users were excluded. Only cases that were sufficiently detailed to be individually analyzed were included. These 32 cases, together with our 10 patients, form the basis of the present analysis. RESULTS: PFJI represented nearly 20% of all spontaneous pyogenic spinal infection diagnosed in our hospital during a 10-year period. This data suggest that PFJI is more common than was previously thought. Of the 42 patients with PFJI, 26 (62%) were men and 16 (38%) were women, with ages ranging from 20 to 86 years (mean age, 59+/-15 years); 55% of patients were older than 60 years. The most common location of infections was the lumbosacral region (86%). All patients presented with severe back pain; fever was noted in 83% of the cases and neurological impairment in nearly 48%. In 38% of patients a systemic predisposing factor for infection was present; the most common conditions were diabetes mellitus, malignancies, and alcoholism. In almost 36% of cases, one or more concomitant infectious processes due to the same microorganism was found, mainly arthritis, skin and soft-tissue infections, endocarditis, and urinary tract infections. Staphylococcus aureus was the most common etiologic microorganism (86% of cases). Bacteremia was documented in 81% of the cases. The diagnosis of PFJI was based mainly on imaging study findings. Paraspinal and/or epidural extension was frequent (81% of cases), but its presence did not indicate a worse prognosis. Medical treatment alone was usually successful. The overall prognosis of PFJI was good, with a mortality rate of only 2%. The great majority of patients were cured without functional sequelae. CONCLUSION: Incidence data from our institution reveal that PFJI is not a rare condition, representing approximately 20% of all pyogenic spinal infections. This entity should be considered in the differential diagnosis of patients with low back pain, especially in the presence of fever, whatever the patient's immunological status.

Group B streptococcus (Streptococcus agalactiae) pyogenic arthritis in nonpregnant adults.

We analyzed the cases of pyogenic arthritis from group B streptococcus (GBS), or, in nonpregnant adults diagnosed in the Hospital Universitari de Bellvitge, a 1,000-bed tertiary care teaching hospital in Barcelona, Spain, during a 10-year period, and we reviewed the available literature to summarize the experience with this infectious entity. From the database of our institution, which does not attend pediatric, obstetric, or burn patients, we collected all microbiologically proven cases of infectious arthritis seen from January 1992 to December 2001. We excluded patients with infection limited to spine; patients with prosthetic joint infection; patients undergoing articular surgery during the year before diagnosis; and those with tuberculous, brucellar, or fungal arthritis. Of a total of 112 patients identified, GBS was the causative organism in 11 (10%) cases. We reviewed the literature using a MEDLINE search (1972-2001), and found 64 additional cases. Of the 75 patients, 34 (45%) were men and 41 (55%) women, with ages ranging from 20 to 87 years (mean age, 57.9 +/- 14.9 yr); 37 patients (49%) were over 60 years. Sixty-eight percent (51/75) of the patients presented with monoarthritis, while in 32% (24/75) more than 1 joint was involved. The most common location was the knee (36%), followed by the shoulder (25%). In 66% (43/65) of cases, bacteremia was documented. In 64% (47/74) of patients, a systemic predisposing factor for infection was noted; the most common conditions were diabetes mellitus, malignancies, and chronic liver diseases. In 31% (23/75) of patients, a concomitant infectious process due to the same microorganism was found, mainly vertebral osteomyelitis and urinary tract infection. Penicillin was the main antibiotic used after bacterial identification; surgical drainage was performed in 36% (27/75) of cases. The overall mortality rate was 9% (7/75). GBS is now a significant causative agent of pyogenic arthritis in nonpregnant adults. In this population, joint infection by GBS is a disease that mainly affects aged patients with underlying medical illnesses; polyarticular involvement, bacteremia, and the presence of a concomitant infectious process are frequent conditions. The case-fatality rate is substantial.