Funda Timurkaynak

Risk factors for extended-spectrum β-lactamase positivity in uropathogenic Escherichia coli isolated from community-acquired urinary tract infections

The aim of this prospective cohort study was to determine the risk factors for community-acquired urinary tract infections (UTIs) caused by extended-spectrum beta-lactamase (ESBL)-positive Escherichia coli and the distribution of the ESBL enzyme types. Structured forms were filled in for patients diagnosed with community-acquired UTI in four different geographical locations in Turkey. The forms and the isolates were sent to the central laboratory at Baskent University Hospital, Ankara. Antimicrobial susceptibility was determined according to the CLSI criteria. PCR and DNA sequencing were used to characterize the bla(TEM), bla(CTX-M) and bla(SHV) genes. Multivariate analysis was performed using logistic regression. A total of 510 patients with UTI caused by Gram-negative bacteria were included in this study. ESBLs were detected in 17 of 269 (6.3%) uropathogenic E. coli isolates from uncomplicated UTIs and 34 of 195 (17.4%) E. coli isolates from complicated UTIs (p <0.001). According to multivariate analysis, more than three urinary tract infection episodes in the preceding year (OR 3.8, 95% CI 1.8-8.1, p <0.001), use of a beta-lactam antibiotic in the preceding 3 months (OR 4.6, 95% CI 2.0-0.7, p <0.001) and prostatic disease (OR 9.6, 95% CI 2.1-44.8, p 0.004) were found to be associated with ESBL positivity. The percentages of isolates with simultaneous resistance to trimethoprim-sulphamethoxazole, ciprofloxacin and gentamicin were found to be 4.6% in the ESBL-negative group and 39.2% in the ESBL-positive group (p <0.001). Forty-six of 51 ESBL-positive isolates (90.2%) were found to harbour CTX-M-15. Therapeutic alternatives for UTI, particularly in outpatients, are limited. Further clinical studies are needed to guide the clinicians in the management of community-acquired UTIs.

Bloodstream infections caused by ESBL-producing E. Coli and K. pneumoniae: risk factors for multidrug-resistance

This prospective case-control study was conducted from October 2003 to June 2007 to evaluate risk factors for multidrug resistance among extended-spectrum-b-lactamase-producing Escherichia coli and Klebsiella spp. (ESBL-EK) isolates in blood cultures. All adult patients (>18 years old) whose blood cultures grew ESBL-EK during the study period were included. An ESBL-EK isolate was defined as MDR if it was resistant to at least one member of following two classes of antibiotics: aminoglycosides (amikacin, gentamicin, or netilmycin) and fluoroquinolones (ofloxacin, or ciprofloxacin). Case patients were those with a MDR ESBL-EK isolate, and control patients were those with a non-MDR ESBL-EK isolate. A total of 94 bloodstream infections, including 37 (39,4%) bloodstream infections with ESBL-producing E. coli and 57 (60,6%) with ESBL-producing K. pneumoniae,in 86 patients were enrolled. Thirty episodes (31.9%) were due to MDR ESBL-EK. The only independent risk factor for MDR ESBL-EK was duration of hospitalization before bacteraemia (OR 3.88; 95% CI 1.55-9.71; p=0.004). The rate of multidrug resistance among ESBL-EK bloodstream isolates was high, and duration of hospitalization before bacteraemia was the only indeepended risk factor for the MDR ESBL-EK bloodstream infections.

Evaluation of Oxidative Status in Patients with Brucellosis

Oxidative stress can be defined as an increase in oxidants and/or a decrease in antioxidant capacity. We aimed to determine total antioxidant capacity (TAC), total peroxide, malondialdehyde and catalase levels in plasma samples, and calculation of oxidative stress index (OSI) in patients with brucellosis to evaluate their oxidative status using a novel automated method. Sixty-nine patients with brucellosis and 69 healthy control subjects were included in the present study. Plasma levels of total peroxide and malondialdehyde were significantly increased in patients as compared with healthy controls (p<0.001 and p<0.001, respectively). In contrast, TAC level was significantly lower in patients as compared with controls (p<0.001). There was no statistically significant difference between the catalase results of the two groups (p>0.05). OSI level was significantly increased in patients as compared with healthy controls (p<0.001). In conclusion, oxidants were increased and antioxidants were decreased in patients with brucellosis. Oxidative stress was increased in patients with brucellosis.

Risk factors for candidemia with non-albicans Candida spp. in intensive care unit patients with end-stage renal disease on chronic hemodialysis

BACKGROUND/PURPOSE The objective of this study was to describe factors associated with bloodstream infections (BSIs) with non-albicans Candida species (NAC), compared with Candida albicans BSIs, and antifungal susceptibility patterns in adult intensive care unit (ICU) patients with chronic renal failure undergoing hemodialysis. To the best of our knowledge, this is the first study to report the potential factors for NAC candidemia in ICU patients with end-stage renal disease on chronic hemodialysis. METHODS This prospective, observational, multicenter study was conducted in the two centers of Baskent University between January 2007 and July 2010. All adult patients excluding patients with neutropenia, malignancy, glucocorticoid treatment or AIDS, were included. RESULTS Sixty cases (58.8%) of candidemia were due to C. albicans and 42 (41.2%) to NAC. Multivariate regression analysis revealed that the presence of a central venous catheter was the only risk factor independently associated with BSI due to NAC (p=0.046, odds ratio: 5.90, 95% confidence interval: 1.032-33.717). Mortality was more frequent in those with NAC than C. albicans BSIs (64.3% vs. 55%), but the difference was not significant (p=0.067). Except for two Candida glabrata strains, which were dose-dependently fluconazole susceptible, all Candida species were susceptible to fluconazole, caspofungin, voriconazole and amphotericin B. CONCLUSION Central venous catheterization was the only factor significantly associated with BSI due to NAC in ICU patients with end-stage renal disease.

A case of brucellosis with abscess of the iliacus muscle, olecranon bursitis, and sacroiliitis

Brucellosis is a systemic infection involving many organs and tissues. The musculoskeletal system is one of the most commonly affected. The disease can present with sacroiliitis, peripheral arthritis, spondylitis, paraspinal abscess, bursitis, and osteomyelitis. A 25-year-old male patient was admitted with fever of 20-day duration, right-sided hip pain, and night sweating. A Brucella standard tube agglutination test was positive at a titer of 1/160. Magnetic resonance imaging (MRI) of the hip joint showed right sacroiliitis and a hyperintense, nodular, lobulated mass within the right iliacus muscle, consistent with abscess. The patient was started on intramuscular streptomycin at a dose of 1 g/day, oral rifampin 600 mg/day, and doxycycline 200 mg/day. On day 20 of treatment, the patient was admitted with swelling and pain over the left elbow for the past week. MRI of the left elbow was performed, which showed fluid edema suggestive of olecranon bursitis. Taking the patients complaints into consideration, rifampin and doxycycline treatment were maintained for a year. Pain at the hip joint and elbow resolved and MRI findings disappeared. Abscess of the iliacus muscle, which has not been reported before, and the olecranon bursitis that developed during treatment make this case worth presenting.

Brucellosis in cases of end-stage renal disease

BACKGROUND Patients with brucellosis frequently present with joint and bone pain. However, brucellosis may be overlooked in patients with end-stage renal disease (ESRD) who undergo dialysis since amyloidosis due to renal osteodystrophy and beta-2 microglobulinaemia may cause bone pain as well. Only four cases of end-stage renal failure accompanied by brucellosis have been reported in the literature. We evaluated clinical and laboratory characteristics and organ involvement of seven brucellosis patients with end-stage renal failure and compared them with brucellosis cases without any renal diseases. METHODS This is a prospective study and involved 158 patients diagnosed with brucellosis. All the patients were divided into two groups: brucellosis patients with ESRD (Group 1) and brucellosis patients without any renal disease (Group 2). RESULTS Group 1 included 7 patients (5 males and 2 females with the mean age 52.1 +/- 14 years) and Group 2 included 151 patients (62 males and 89 females with the mean age 45.4 +/- 16 years). Out of seven patients in Group 1, one had neurobrucellosis, one had paravertebral abscess, one had epidural abscess and one had peripheral arthritis. In addition, one patient in Group 1 with accompanying sickle cell anaemia presented with pain crisis and was diagnosed with brucellosis on admission. Serological tests were negative for brucellosis, but Brucella melitensis was isolated in blood cultures in another patient with accompanying continuous ambulatory peritoneal dialysis. Group 1 more frequently had joint pain and malaise. B. melitensis was isolated in blood cultures in blood taken in the absence of fever in half of the cases in Group 1 positive for B. melitensis in blood cultures on admission. CONCLUSION B. melitensis can be isolated in blood cultures even in the absence of high fever. In fact, in the present study, B. melitensis was isolated in most of the cases without high fever. For this reason, blood cultures should be performed in cases of end-stage renal diseases suspected of having brucellosis although fever is not present. In addition, brucellosis can present various clinical forms in endemic areas, mimics several diseases and can be characterized with severe complications.

Bacteremia among liver and kidney transplant recipients: etiologic agents and antimicrobial susceptibilities

Dear Editor,In this retrospective study, we compared eti-ologies and antibiotic susceptibility patterns among kidney and liver transplant recipi-ents with bacteremia in two 1-year periods, 2005 and 2009. Time of bacteremia onset were computed in the two post-transplant periods, first six months (early period) and more than six months (late period) after the transplantation. Clinical characteristics including age, sex, previous antibiotic or antifungal therapy within three months, co-morbidities, central venous catheterization (CVC), mechanical ventilation, cytomeg-alovirus (CMV) disease, hemodialysis after transplantation, intra-abdominal drainage or biliary stenting, origin of bacteremia, al-lograft dysfunction, mortality, microbiolog -ical isolates, total parenteral nutrition were collected for the analysis. There were 14 bacteremic episodes among six kidney and eight liver recipients in the year 2005, and there were 23 episodes among six kidney and 17 liver recipients in the year 2009. Characteristics of the episodes in the two study periods of 2005 and 2009 were similar. Overall, there were 15 bacteremic episodes in the early period and 22 in the late period. Trimethoprim-sulphamethoxazole (TMP-SMX) prophylaxis (n = 13

In vitro Susceptibility of Tigecycline against Multidrug-Resistant Gram-Negative Strains: Etest versus Agar Dilution

Background and Aim: Tigecycline is a semi-synthetic tetracycline with activity against most multidrug-resistant (MDR) bacteria. Methods: We studied in vitro activity of tigecycline by agar dilution (AD) and Etest methods to evaluate their correlation. The study included 206 isolates of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli, Klebsiella pneumoniae and MDR Acinetobacter baumannii recovered from blood cultures of patients of Baskent University between 2008 and 2010. Results: ESBL-producing E. coli had MIC50/MIC90 values of 0.5/0.5 µg/ml by AD and 0.25/0.5 µg/ml by Etest. ESBL-producing K. pneumoniae had MIC50/MIC90 values of 1/2 µg/ml by AD and 0.75/2 µg/ml by Etest, whereas MDR A. baumannii had MIC50/MIC90 values of 4/4 µg/ml by AD and 2/4 µg/ml by Etest. The correlation between AD and Etest was weak for ESBL-producing E. coli and strong for ESBL-producing K. pneumoniae and MDR A. baumannii. Tigecycline MIC values for ESBL-producing E. coli were lower than the tigecycline concentration, while they were higher than the concentrations attainable by treatment doses for A. baumannii. Conclusion: Tigecycline is an appropriate agent in the treatment of E. coli bacteremia, but it is not for treating A. baumannii bacteremia. Tigecycline could be used for K. pneumoniae bacteremia treatment after determining its MIC value. Determining the MIC value by gold-standard methods is more appropriate due to the correlation between Etest and AD at high MIC values.

The Place and the Efficacy of Infectious Disease Consultations in the Hospitals

Abstract Our study aims to determine the efficacy of infectious disease consultations and the interrelations between doctors in this social laboratory. This study was conducted at 34 centers located in 22 cities across Turkey and contributed by 210 infectious disease specialists (IDSs) and 970 non–infectious disease specialists (NIDSs), totaling 1180 medical doctors. Infectious disease specialists and NIDSs have separately contributed by responding to questionnaires designed specifically for the consultation process. It appears that a satisfactory collaboration has been established between IDSs and NIDSs during the consultation practices. There are some discrepancies in the perceptions of some of the NIDSs. These are the evaluation of patients holistically, the expectation of NIDSs in critical infection cases to start the therapy immediately, losing the support of drug companies by NIDSs, and the restriction of NIDSs in routine medical practice. On the other hand, NIDSs seem to have real problems in the diagnosis or treatment of infectious diseases. The consultation service provided by the IDSs in Turkey is widely accepted among other clinicians and appears to be of a crucial importance.

In vitro activity of tigecycline against resistant micro-organisms isolated from burn patients.

Infections in burn patients are usually caused by multidrug-resistant micro-organisms. Tigecycline, a derivative of glycylcyclines, is an effective antibiotic against the resistant strains. The aim of this study is to determine the in vitro activity of tigecycline against the multidrug-resistant bacteria isolated from burn patients. Fourty-seven bacteria isolated from 118 patients hospitalized in the burn unit during 2003-2006 were included in the study. Gram-negative bacteria that were resistant to at least six broad-spectrum antibiotics, methicillin-resistant staphylococci and ampicillin-resistant enterococci were studied. Minimal inhibitory concentration values of tigecycline against these bacteria were tested by E-test strips. Susceptibility breakpoints were determined according to the previous studies; <or=0.25mg/L for enterococci, <or=0.5mg/L for staphylococci and <or=2mg/L for Acinetobacter baumannii. Thirty-six percent of the materials were obtained from tissue specimens, 30% from wound, 25% from blood and 9% from other samples (e.g., catheter, tracheal aspiration, urine). MIC(90) values were 2, 0.25 and 1.5mg/L and susceptibility rates were 99.4%, 93.6%, 85.5% for A. baumannii, enterococci and MRSA, respectively. To conclude, this study demonstrated that tigecycline exhibits in vitro activity against clinical isolates of MDR A. baumannii, MRSA, and Enterococcus spp. isolated from burn patients. Tigecycline is a promising therapeutic option for difficult to treat burn infections due to these pathogens.