Alloprevotella rava isolated from a mixed infection of an elderly patient with chronic mandibular osteomyelitis mimicking oral squamous cell carcinoma.

The anaerobic, Gram-negative bacillus Alloprevotella rava has recently been described in the human oral cavity. To our knowledge, this species has not been isolated from chronic osteomyleitis samples. We present the first case of A. rava infection in a 92-year-old woman with polymicrobial chronic mandibular osteomyelitis, mimicking oral squamous cell carcinoma.

Rapid emergence of colistin resistance and its impact on fatality among healthcare-associated infections.

This article describes the emergence of resistance and predictors of fatality for 1556 cases of healthcare-associated Gram-negative bloodstream infection in 2014 and 2015. The colistin resistance rate in Klebsiella pneumoniae was 16.1%, compared with 6% in 2013. In total, 660 (42.4%) cases were fatal. The highest fatality rate was among patients with Acinetobacter baumannii bacteraemia (58%), followed by Pseudomonas aeruginosa (45%), Klebsiella pneumoniae (41%), Enterobacter cloacae (32%) and Escherichia coli (28%). On multi-variate analysis, the minimum inhibitory concentrations for carbapenems [odds ratio (OR) 1.02, 95% confidence interval (CI) 1.01-1.04; P = 0.002] and colistin (OR 1.1, 95% CI 1.03-1.17; P = 0.001) were found to be significantly associated with fatality.

The preparation of ciprofloxacin hydrochloride-loaded chitosan and pectin microspheres: their evaluation in an animal osteomyelitis model.

Ciprofloxacin hydrochloride-loaded microspheres were prepared by a spray-drying method using pectin and chitosan. The effects of different polymers and drug ratios were investigated. The most appropriate carriers were selected by in vitro testing. A rat methicillin-resistant Staphylococcus aureus osteomyelitis model was used to evaluate the effects of the loaded microspheres. The drug was released rapidly from the pectin carrier but this was more sustained in the chitosan formulation.Chitosan microspheres loaded with ciprofloxacin hydrochloride were more effective for the treatment of osteomyelitis than equivalent intramuscular antibiotics.

Healthcare-associated Gram-negative bloodstream infections: antibiotic resistance and predictors of mortality.

This article describes the prevalence of antibiotic resistance and predictors of mortality for healthcare-associated (HA) Gram-negative bloodstream infections (GN-BSI). In total, 831 cases of HA GN-BSI from 17 intensive care units in different centres in Turkey were included; the all-cause mortality rate was 44%. Carbapenem resistance in Klebsiella pneumoniae was 38%, and the colistin resistance rate was 6%. Multi-variate analysis showed that age >70 years [odds ratio (OR) 2, 95% confidence interval (CI) 1.22-3.51], central venous catheter use (OR 2.1, 95% CI 1.09-4.07), ventilator-associated pneumonia (OR 1.9, 95% CI 1.1-3.16), carbapenem resistance (OR 1.8, 95% CI 1.11-2.95) and APACHE II score (OR 1.1, 95% CI 1.07-1.13) were significantly associated with mortality.

Predictors for limb loss among patient with diabetic foot infections: an observational retrospective multicentric study in Turkey.

We aimed to investigate the predictors for limb loss among patients with diabetes who have complicated skin/soft-tissue infections. In this observational study, consecutive patients with diabetic foot infection (DFI) from 17 centres in Turkey, between May 2011 and May 2013 were included. The Turkish DFI Working Group performed the study. Predictors of limb loss were investigated by multivariate analysis. In total, 455 patients with DFI were included. Median age was 61 years, 68% were male, 65% of the patients were hospitalized, 52% of the patients had used antibiotics within the last month, and 121 (27%) had osteomyelitis. Of the 208 microorganisms isolated, 92 (44.2%) were Gram-positive cocci and 114 (54.8%) were Gram-negative rods (GNR). The most common GNR was Pseudomonas; the second was Escherichia coli, with extended spectrum ß-lactamase positivity of 33%. Methicillin-resistant Staphylococcus species were found in 14% (29/208). Amputations were performed in 126/455 (28%) patients, 44/126 (34%) of these were major amputations. In multivariate analysis, significant predictors for limb loss were, male gender (OR 1.75, 95% CI 1.04-2.96, p 0.034), duration of diabetes >20 years (OR 1.9, 95% CI 1.18-3.11, p 0.008), infected ulcer versus cellulitis (OR 1.9, 95% CI 1.11-3.18, p 0.019), history of peripheral vascular disease (OR 2, 95% CI 1.26-3.27, p 0.004), retinopathy (OR 2.25, 95% CI 1.19-4.25, p 0.012), erythrocyte sedimentation rate >70 mm/hr (OR 1.6, 95% CI 1.01-2.68, p 0.05), and infection with GNR (OR 1.8, 95% CI 1.08-3.02, p 0.02). Multivariate analysis revealed that, besides the known risk factors such as male gender, duration of diabetes >20 years, infected ulcers, history of peripheral vascular disease and retinopathy, detection of GNR was a significant predictor of limb loss.

Resistance to extended-spectrum cephalosporins, caused by PER-1 beta-lactamase, in Salmonella typhimurium from Istanbul, Turkey.

Two Salmonella typhimurium isolates were studied, one as a representative from a series of neonatal meningitis cases treated at an Istanbul teaching hospital, the other from a gastro-enteritis case seen at a different Istanbul hospital. Both isolates were resistant to extended-spectrum cephalosporins, as well as penicillins, aminoglycosides and chloramphenicol. Cephalosporin resistance depended on production of PER-1 beta-lactamase, which is an extended-spectrum class A enzyme that is only distantly related to TEM and SHV enzymes, and which was previously known only from Pseudomonas aeruginosa isolates. The PER-1 gene was carried by an 81-MDa plasmid, which also determined resistance to aminoglycosides and chloramphenicol. Although it was not self-transmissible to Escherichia coli, this element did transfer if mobilised with plasmid pUZ8. The two S. typhimurium isolates gave indistinguishable DNA restriction patterns and, in addition to their 81-MDa plasmid, also contained 52- and 2.8-MDa plasmids, the last of these encoded TEM-1 enzyme. The two isolates were identical in serotype, antibiogram and plasmid-profile but nevertheless differed in phage type, and, therefore, represented distinct strains. The emergence of cefotaxime and ceftriaxone resistance in salmonellae is disturbing, since these agents are preferred therapy for neonatal meningitis caused by members of the genus.

An unusual native tricuspid valve endocarditis caused by Candida colliculosa.

Candida colliculosa, which grew in blood cultures of a 71-year-old retired man with fever of unknown origin that had lasted for 7 months, in conjunction with transthoracic echocardiography, demonstrating a 20-mm vegetation, superior to the tricuspid valve, herniating into the right atrial cavity. The finding led to the diagnosis of fungal endocarditis. Fluconazole, 600 mg daily, was commenced for 8 days; followed by amphotericin B, 1 mg/kg daily. On the fourth day of the amphotericin B treatment, the patient underwent replacement of the infected tricuspid valve. Even though the initial postoperative period was relatively uncomplicated, the patient died after a gross aspiration on the 67th day of his hospital stay, despite aggressive cardiovascular support and antimicrobial therapy. This is the first report of a native tricuspid valve fungal endocarditis due to C. colliculosa or Torulaspora delbrueckii, which is not known to be a human pathogen.

Treatment of community-acquired pneumonia in hospitalised patients.

Community-acquired pneumonia (CAP) can be life-threatening. The prognosis is generally poorest in elderly patients and/or those with underlying chronic conditions, but fatalities can occur in all age groups. Current challenges in the clinical management of CAP are discussed, and the criteria for identifying those patients who should be treated in hospital with initial intravenous therapy are considered. Rapid initiation of therapy is important, using an agent that provides coverage against the most likely pathogens--Streptococcus pneumoniae and the atypical organisms. There is an increasing tendency to minimise the duration of intravenous therapy, with an early transition to oral therapy and the rapid return of the patient to the community. The efficacy of oral macrolides in the treatment of CAP is well established. Evidence for the use of intravenous azithromycin to provide effective and well-tolerated, first-line intervention in the hospitalized CAP patient is summarised.

Vancomycin-gentamicin synergism revisited: effect of gentamicin susceptibility of methicillin-resistant Staphylococcus aureus.

Vancomycin monotherapy of deep-seated staphylococcal infection may be associated with poor bacteriological response. We evaluated 24 unique patient isolates of methicillin-resistant Staphylococcus aureus (MRSA) for vancomycin-gentamicin synergism by determining time-kill curves for vancomycin at 10 micrograms/ml and gentamicin at 1 microgram/ml. Nine MRSA strains showed high-level gentamicin resistance (HLGR) (MIC, > 500 micrograms/ml), and 15 did not. Vancomycin-gentamicin demonstrated synergism against none of the HLGR strains. For the non-HLGR strains, gentamicin agar dilution MICs ranged from 0.5 to > 128 micrograms/ml. Vancomycin-gentamicin demonstrated synergism against six of these strains and indifference against nine of them. There was no relationship between the agar dilution MIC of gentamicin and the occurrence of synergism against non-HLGR strains. We conclude that a gentamicin MIC of > 500 micrograms/ml predicts a lack of vancomycin-gentamicin synergism for strains of MRSA. For non-HLGR strains, synergism is not predictable from the gentamicin MIC.

In vitro activities of two novel oxazolidinones (U100592 and U100766), a new fluoroquinolone (trovafloxacin), and dalfopristin-quinupristin against Staphylococcus aureus and Staphylococcus epidermidis.

Two oxazolidinones (U100592 and U100766), trovafloxacin, and a streptogramin combination (dalfopristin-quinupristin) were highly active in vitro against Staphylococcus aureus and Staphylococcus epidermidis, including methicillin-resistant strains. Trovafloxacin was more active than ciprofloxacin. Time-kill synergy studies demonstrated indifference for the oxazolidinones combined with vancomycin and rifampin against methicillin-resistant staphylococci. Spontaneous resistance was observed with all agents.

Antibiotic prophylaxis in elective thoracic surgery: cefuroxime versus cefepime.

BACKGROUND: Infection is one of the major morbidity factors after thoracic surgery. Although different prophylactic regimens have been used to prevent this complication, the ideal prophylactic agent, dose and duration of administration remain unknown. METHODS: All patients included underwent elective lung resection. 102 selected patients consecutively scheduled for major thoracic surgery were enrolled in this study and randomized into either the cefuroxime group (n = 50) or the cefepime group (n = 52). RESULTS: Twelve pathologic bacterium strains were isolated in the cefepime group, whereas only 5 pathogenic strains were isolated in the cefuroxime group; the difference was statistically significant (p = 0.04). Two empyemas (3.8 %) in the cefepime group were noted, while the cefuroxime group showed no cases of empyema (p = 0.16). Overall infection rate (pneumonia + bronchopneumonia + empyema) were 14.0 % and 26.7 % in the cefuroxime and the cefepime groups, respectively (p = 0.12). Using chest radiography, pulmonary infiltration was found to be more frequent in the cefuroxime group (p=0.002). CONCLUSION: Cefuroxime as a prophylactic agent in major thoracic surgical operations was marginally more effective than cefepime, and presented an additional cost advantage.

Epidemiology of ciprofloxacin resistance and its relationship to extended-spectrum beta-lactamase production in Klebsiella pneumoniae isolates causing bacteremia.

A prospective study of Klebsiella pneumoniae bacteremia was performed in 12 hospitals in 7 countries. Of 452 episodes of bacteremia, 25 (5.5%) were caused by K. pneumoniae that was resistant in vitro to ciprofloxacin. Extended-spectrum beta-lactamase (ESBL) production was detected in 15 (60%) of 25 ciprofloxacin-resistant isolates, compared with 68 (16%) of 427 ciprofloxacin-susceptible strains (P=.0001). Multivariate analysis revealed that risk factors for ciprofloxacin resistance in K. pneumoniae included prior receipt of a quinolone (P=.0065) and an ESBL-producing strain (P=.012). In all, 18% of ESBL-producing isolates were also ciprofloxacin-resistant. Pulsed-field gel electrophoresis showed that 11 of the 15 ciprofloxacin-resistant ESBL-producing strains belonged to just 4 genotypes, suggesting that patient-to-patient transmission of such strains occurred. The close relationship between ESBL production and ciprofloxacin resistance is particularly worrisome because the first reported instance of plasmid-mediated ciprofloxacin resistance has been in an isolate of K. pneumoniae also possessing an ESBL.

Outcome of cephalosporin treatment for serious infections due to apparently susceptible organisms producing extended-spectrum beta-lactamases: implications for the clinical microbiology laboratory.

Although extended-spectrum beta-lactamases (ESBLs) hydrolyze cephalosporin antibiotics, some ESBL-producing organisms are not resistant to all cephalosporins when tested in vitro. Some authors have suggested that screening klebsiellae or Escherichia coli for ESBL production is not clinically necessary, and when most recently surveyed the majority of American clinical microbiology laboratories did not make efforts to detect ESBLs. We performed a prospective, multinational study of Klebsiella pneumoniae bacteremia and identified 10 patients who were treated for ESBL-producing K. pneumoniae bacteremia with cephalosporins and whose infecting organisms were not resistant in vitro to the utilized cephalosporin. In addition, we reviewed 26 similar cases of severe infections which had previously been reported. Of these 36 patients, 4 had to be excluded from analysis. Of the remaining 32 patients, 100% (4 of 4) patients experienced clinical failure when MICs of the cephalosporin used for treatment were in the intermediate range and 54% (15 of 28) experienced failure when MICs of the cephalosporin used for treatment were in the susceptible range. Thus, it is clinically important to detect ESBL production by klebsiellae or E. coli even when cephalosporin MICs are in the susceptible range (