Retrospective evaluation of the patients with urinary tract infections due to carbapenemase producing Enterobacteriaceae.

In this study, we aimed to investigate retrospectively the patients with carbapenem-resistant Enterobacteriaceae urinary tract infections (UTIs) in the terms of demographic findings, antibiotic sensitivity patterns and clinical features along with the treatment options. This study was performed at a tertiary-care educational university hospital. Adult (>18 years old) patients diagnosed with culture proven UTI due to carbapenem-resistant Klebsiella pneumoniae (between December 2016 to December 2017) were included in the study. Antimicrobial susceptibility testing of the isolates was performed with the VITEK 2 system (bioMérieux). Resistance to imipenem, ertapenem, and meropenem was tested by E-test (bioMérieux). The results were interpreted according to the EUCAST criteria. A total number of 100 patients (34% female, mean age 61.69 ± 1.65 years) were included in this study. One month all-cause mortality rate was 19%. Microbiologic eradication rate was 88.7% while it was significantly higher in combination therapy (65/70 vs. 14/19, p = 0.019) and carbapenem long-lasting (4 h) infusion subgroups (54/56 vs. 2/56, p = 0.005). Relapse and reinfection rates were 61.7 and 29.7%, respectively. Logistic regression analysis for mortality risk factors resulted as history of ertapenem usage (OR: 4.74, 95% CI: 0.678-33.201, p = 0.117), lack of microbiologic eradication (OR: 21.7, 95% CI: 1.906-247.375, p = 0.013) and ICU stay (OR: 54.8, 95% CI: 4.145-726.324, p = 0.002). Combination, carbapenem long-lasting infusion and double carbapenem therapies seem to result in higher microbiologic eradication rates and thus may effect the mortality rates of these group of patients. Randomized-controlled studies should be performed in this critical patient group to confirm these results.

Tigecycline in the treatment of multidrug-resistant Acinetobacter baumannii meningitis: Results of the Ege study.

OBJECTIVES: In this study we retrospectively reviewed A. baumannii meningitis cases treated with tigecycline including regimens and evaluated the efficacy of tigecycline in the therapy. PATIENTS AND METHODS: Study was performed in seven tertiary-care educational hospitals from five cities of Turkey and one center from France. We extracted data and outcomes of all adult (aged >18) patients with culture proven A. baumannii meningitis treated with tigecycline including antibiotic therapy until April 2016. RESULTS: A total of 23 patients (15 male and eight female) fulfilled our inclusion criteria. All Acinetobacter strains were carbapenem-resistant and susceptible to tigecycline. Six cases received tigecycline monotherapy while 17 received tigecycline including combination therapy (10 with colistin, 4 with netilmicin, 3 with amikacin, 4 with meropenem). Seven of 23 cases (30%) died during the tigecycline including therapy (1 in monotherapy, 4 in colistin, 2 in netilmicin, 1 amikacin, one case received tigecycline + netilmicin followed by tigecycline + colistin). Hence, overall end of treatment (EOT) success was 70%. However, since further 27% died due to additional nosocomial infections, overall clinical success (relieved symptoms at the EOT and one-month post-therapy survival without any relapse or reinfection) decreased to 43%. CONCLUSION: We conclude that tigecycline may be an alternative in the salvage treatment of nosocomial multidrug-resistant Acinetobacter spp. meningitis. Acinetobacter spp. Meningitis.

Vancomycin versus linezolid in the treatment of methicillin-resistant Staphylococcus aureus meningitis.

BACKGROUND: Vancomycin is the mainstay of treatment for methicillin-resistant Staphylococcus aureus (MRSA) meningitis. However, successful outcomes with linezolid have not been reported in a large series of patients. We conducted a single-center retrospective cohort study to compare vancomycin with linezolid in the treatment of MRSA meningitis. METHODS: We extracted data and outcomes for all adult patients (age >18 years) with culture-proved MRSA meningitis who received vancomycin or linezolid between January 2006 and June 2011. A definite diagnosis of meningitis was based on the isolation of MRSA in at least one cerebrospinal fluid (CSF) culture and findings in CSF that are typical of the infection. Linezolid was given intravenously (IV) at a dosage of 600 mg q12h and vancomycin IV at 500 mg q6h. RESULTS: A total of 8 patients with MRSA meningitis (5 male, 3 female; age [mean±SD] 61.6±13.2 years) received vancomycin and 9 patients (7 male, 2 female; age 59.1±15.6 years) received linezolid. All isolated strains of MRSA were susceptible to both vancomycin and linezolid. The rates of microbiologic success with linezolid or vancomycin, in terms of clearance of MRSA from CSF on day 5, were 7/9 and 2/8 (p=0.044, Fisher exact test). No severe adverse events occurred in either treatment arm of the study. One-month survival of the patients in whom treatment was successful microbiologically was 2/2 in the vancomycin-treated group and 4/7 in the linezolid-treated group. Minimum inhibitory concentration (MIC) data for vancomycin were available for 5/6 treatment failures with vancomycin, and vancomycin MIC values of these five strains were 2 mg/L. CONCLUSION: Analysis of the findings in the limited cohorts in our study suggests that linezolid is superior to vancomycin for treating MRSA meningitis, especially in cases in which there is a high MIC (2 mg/L) for vancomycin. A clinical study involving larger cohorts may increase the evidence available in relation to this question.

In vitro activity of linezolid & quinupristin/dalfopristin against Gram-positive cocci.

BACKGROUND & OBJECTIVES: Since the incidence of vancomycin- and methicillin-resistant Gram-positive infections continue to increase, novel antimicrobials such as linezolid and streptogramin may provide new options to treat patients. The aim of this study was to investigate in vitro susceptibility of Enterococcus faecium resistant to glycopeptides, coagulase negative staphylococci and S. aureus resistant to methicillin isolated mainly from blood and also rectal swab cultures of patients against quinupristin/dalfopristin and linezolid. METHODS: The in vitro susceptibility to linezolid and quinupristin/dalfopristin for a total of 332 isolates of Gram-positive cocci [127 methicillin-resistant Staphylococcus aureus, 109 methicillin-resistant coagulase negative staphylococci (71 S. epidermidis, 38 S. haemolyticus) and 96 vanA genotype vancomycin-resistant Enterococcus faecium] was investigated by E test. RESULTS: All MRSA and MRCoNS isolates were susceptible to linezolid (MICs < 4.0 mg/l). Ninety per cent of VRE isolates were inhibited by linezolid at concentration of 2.0 mg/l and presented similar activities to quinupristin/dalfopristin. MICs for quinupristin/dalfopristin against staphylococci were also low (MIC(90) = 1.0 mg/l for both MRSA and MRCoNS isolates). INTERPRETATION & CONCLUSION: The results of the present study demonstrated that quinupristin/ dalfopristin and linezolid, have good in vitro activity against MRSA, MRCoNS and vancomycin resistant E. faecium in Turkey. These drugs could be promising therapeutic options in an era of rapidly growing antibiotic resistance in all parts of world.