Bilgul Mete

Blood stream infections due to OXA-48-like carbapenemase-producing Enterobacteriaceae: treatment and survival

BACKGROUND Blood stream infections (BSIs) due to carbapenem-resistant Enterobacteriaceae (CRE) are associated with high hospital mortality rates and present a tremendous challenge to clinicians. The optimal treatment remains undefined. We aimed to investigate the risk factors for mortality and the correlation between different treatment modalities and outcomes. METHODS The clinical characteristics and treatment outcomes of a cohort of 36 patients with BSIs due to CRE were investigated and a retrospective nested case-control study of surviving and non-surviving patients was conducted. RESULTS Fifty percent of the cases were male and the mean patient age was 54.9 ± 15.8 years. Klebsiella pneumoniae was the etiological agent in 26 cases (72.2%), Escherichia coli in eight (22.2%), and Enterobacter aerogenes in two (5.5%). All strains were phenotypically positive for carbapenemase activity and all except two (one E. coli and one K. pneumoniae) yielded both blaOXA-48 carbapenemases and blaCTX-M-type extended-spectrum beta-lactamases (ESBLs) in PCR products. The 14-day, 28-day, and all-cause in-hospital mortality rates were 41.6%, 50%, and 58.3%, respectively. The median time to death was 8 days (range 2-52 days). No significant differences were observed between survivors and non-survivors in terms of baseline characteristics, comorbid conditions, etiologies, or sources of bacteremia, however hematological malignancies (p=0.015) and prolonged neutropenia (p=0.044) were more common in non-survivors. Microbiological eradication and clinical response within 7 days were two major determinants of 28-day attributable mortality (p=0.001 and p=0.001, adjusted r(2)=0.845). Colistin-based dual combinations, and preferably triple combinations, were associated with significantly better outcomes when compared to non-colistin-based regimens (p<0.001). Time to active treatment had a significant effect on the course of infection (p=0.014). CONCLUSION Earlier active treatment with colistin based regimens and microbiological and clinical response within 7 days are major predictors of survival in cases of BSIs due to CRE. Rectal screening offers the advantage of earlier recognition and prompt empirical treatment.

Aspergillus fumigatus infection as a delayed manifestation of prosthetic knee arthroplasty and a review of the literature

Abstract Fungal infection after total joint arthroplasty is a very rare but serious complication and a challenge to the treating and consulting physicians. The literature includes little information about the treatment protocol for Aspergillus infection after total knee arthroplasty, since only 3 cases have been reported. We describe the case of a non-immunocompromised patient who lacked predisposing risk factors and presented with pain and swelling. An aspiration under sterile conditions revealed Aspergillus fumigatus. The patient was treated successfully with a 2-stage exchange reimplantation and 6-week course of liposomal amphotericin B. At 4 y after reimplantation, the patient had no evidence of infection or pain.

A new model using platelet indices to predict liver fibrosis in patients with chronic hepatitis B infection

SummaryBackgroundWe aimed to investigate whether mean platelet volume (MPV) and platelet distribution width (PDW) are variables determining the severity of liver fibrosis in patients with chronic HBV infection.MethodsPatients were divided into two groups with fibrosis scores of 0–2 and 3–6 (according to Ishac scoring system). Whether MPV and PDW were independent variables determining the severity of liver fibrosis score or not was investigated by comparing these groups.ResultsOf the 111 cases, 74 (66.7 %) were male (mean age 37.7 ± 11.6 years). Twenty-two of the cases (19.8 %) were HBeAg-positive. Fibrosis scores of 42 cases (37.8 %) were ≥ 3 and the remaining 69 cases had fibrosis scores < 3 (62.2 %). Independent variables determining the severity of fibrosis score were low levels of albumin and mean platelet volume, and high levels of prothrombin time and PDW (Odds ratio (95 % confidence interval) and p values were 0.105 (0.018–0.605) and 0.012 for albumin, 0.402 (0.234–0.692) and 0.001 for mean platelet volume, 1.529 (1.183–1.975) and 0.001 for PDW, and 0.924 (0.875–0.976) and 0.005 for prothrombin time, respectively). The sensitivity, specificity, positive predictive value and negative predictive value of regression model that is established using above mentioned parameters were 88.1, 75.3, 68.5, and 91.7 %, respectively (AUC = 0.886, p = 0.0001).ConclusionsMPV and PDW are independent variables determining the severity of liver fibrosis, and the regression model that is established using these parameters along with other markers, may give more information about the severity of liver fibrosis.ZusammenfassungHintergrundWir untersuchten, ob das mittlere Thrombozytenvolumen und die Verteilung der Thrombozytenbreite Variable sind, die den Schweregrad der Leberfibrose bei Patienten mit chronischer Hepatitis B (HBV) Infektion bestimmen.MethodenDie Patienten (n = 111, davon waren 74 (66,7 %) männlich, mittleres Alter: 37,7 ± 11,6 Jahre) wurden in 2 Gruppen je nach Fibrose Score (0–2 und 3–6) eingeteilt. Verwendet wurde das Ishac Score System. Ob das mittlere Thrombozytenvolumen und die Breitenverteilung der Thrombozyten unabhängige, den Schweregrad der Leberfibrose bestimmende Variable sind, wurde durch Vergleich dieser Gruppen geprüft.ErgebnisseZweiundzwanzig (19,8 %) Patienten waren HbeAg positiv. Die Fibrose Scores waren bei 42 Patienten (37,8 %) ≥ 3 und bei den restlichen 69 (62,2 %) Patienten < 3. Folgende Parameter stellten sich als unabhängige, den Schweregrad der Leberfibrose bestimmende Variable heraus: niedrige Albumin- und niedrige mittlere Thrombozytenvolumen-Werte, sowie hohe Werte der Prothromin Zeit und der Breite der Thrombozyten (Odds ratio (95 % Konfidenz Intervalle) und p Werte waren respektive: 0,105 (0,018–0,605) und 0,012 für Albumin, 0,402 (0,234–0,692) sowie 0,001 für das mittlere Thrombozytenvolumen, 1,529 (1,183–1,975) and 0,001 für die Verteilung der Thromzytenbreite, und 0,924 (0,875–0,976) and 0,005 für die Prothrombin Zeit). Die Sensitivität, Spezifität, der positive und der negative Vorhersagewert des Regressionsmodells, das unter Verwendung der oben erwähnten Parameter etabliert wurde waren: 88,1, 75,3, 68,5, and 91.7 %, respektive (AUC = 0,886, p = 0,0001).SchlussfolgerungenDas mittlere Thrombozytenvolumen und die Verteilung der Thrombozytenbreite sind unabhängige Variable, die den Schweregrad der Leberfibrose bestimmen. Das auf Basis dieser und anderer Parameter etablierte Regressionsmodell könnte mehr Information über den Schweregrad der Leberfibrose geben.

Efficacy of tigecycline and vancomycin in experimental catheter-related Staphylococcus epidermidis infection: microbiological and electron microscopic analysis of biofilm

Central venous catheters are frequently used. The commonest cause of catheter-related bloodstream infections (CRBSI) is coagulase-negative staphylococci (CoNS) associated with adherent biofilm. Tigecycline, a derivative of tetracycline, acts against strains producing biofilm. In this study, we aimed to determine the effect of tigecycline in a CRBSI model. A single dose of 10(8) colony-forming units (CFU)/mL of slime-producing Staphylococcus epidermidis was given through polyethylene catheters inserted into 24 rabbits. After 72 h, groups of eight rabbits were treated with heparin, vancomycin/heparin or tigecycline/heparin. Blood obtained from peripheral veins and the catheter lumen as well as catheter tips were cultured, and three catheters from each group were studied using electron microscopy. Surfaces were randomly subdivided and areas with ≥50 bacteria were compared. Blood cultures were positive from all heparin-treated rabbits but were negative from those receiving either antibiotic (P<0.001). Catheter tip cultures revealed growth from six, two and one rabbit(s) given heparin, vancomycin and tigecycline, respectively. Electron microscopy showed that catheters from heparin-treated rabbits were most heavily colonised (more areas with ≥50 CFU) compared with catheters from animals treated with vancomycin or tigecycline (P<0.003 and P<0.001, respectively). In conclusion, this study shows that tigecycline and vancomycin are both effective for treating CRBSI due to CoNS. Electron microscopy of catheters themselves suggests that tigecycline is superior to vancomycin (P<0.001). Tigecycline may be useful for the treatment of CRBSI.

A meningitis case due to Stenotrophomonas maltophilia and review of the literature

Stenotrophomonas maltophilia (formerly Xanthomonas maltophilia) is a Gram-negative bacillus increasingly associated with serious nosocomial infections. Here, we describe a 30-year-old male patient who developed meningitis associated with this organism after several neurosurgical procedures. A review of the literature revealed only 15 previous reports. Most cases were associated with neurosurgical procedures. Antimicrobial therapy is complicated by multiple drug resistance of the organism, and trimethoprim-sulfamethoxazole is the recommended agent for treatment.

Diagnosis of chronic brucellar meningitis and meningoencephalitis: the results of the Istanbul-2 study

No detailed data exist in the literature on the accurate diagnosis of chronic brucellar meningitis or meningoencephalitis. A multicentre retrospective chart review was performed at 19 health centres to determine sensitivities of the diagnostic tests. This study included 177 patients. The mean values of CSF biochemical test results were as follows: CSF protein, 330.64 ± 493.28 mg/dL; CSF/ blood-glucose ratio, 0.35 ± 0.16; CSF sodium, 140.61 ± 8.14 mMt; CSF leucocyte count, 215.99 ± 306.87. The sensitivities of the tests were as follows: serum standard tube agglutination (STA), 94%; cerebrospinal fluid (CSF) STA, 78%; serum Rose Bengal test (RBT), 96%; CSF RBT, 71%; automated blood culture, 37%; automated CSF culture, 25%; conventional CSF culture, 9%. The clinician should use every possible means to diagnose chronic neurobrucellosis. The high seropositivitiy in brucellar blood tests must facilitate the use of blood serology. Although STA should be preferred over RBT in CSF in probable neurobrucellosis other than the acute form of the disease, RBT is not as weak as expected. Moreover, automated culture systems should be applied when CSF culture is needed.

Abiotrophia defectiva: A rare cause of infective endocarditis

A case of Abiotrophia defectiva-caused infective endocarditis is described. The patient was successfully treated with penicillin combined with gentamicin. Due to the fastidious nature of the agent, there is a need for special media for isolation and moreover, there is a need for a future development of susceptibility assays applicable to the organism.

First-line monotherapies of tenofovir and entecavir have comparable efficacies in hepatitis B treatment

Background Hepatitis B virus (HBV) infection is a health problem worldwide. Current treatment options for chronic hepatitis B (CHB) are nucleoside or nucleotide analogues and pegylated interferons. Tenofovir and entecavir are much more commonly used as they have better efficacy, tolerability, and high genetic barriers to resistance. Aim The aim of this study was to assess the efficacies of tenofovir and entecavir in previously untreated CHB patients in a treatment cohort. Patients and methods We included CHB patients in a cohort including previously untreated HBeAg-positive and HBeAg-negative patients from 10 centers in Istanbul, Turkey. The patients were compared in terms of baseline characteristics, decrease in alanine transaminase (ALT), decrease in HBV-DNA to undetectable levels, HBeAg loss and anti-HBe development (among baseline HBeAg-positive patients), interventions to therapy because of lack of efficacy, side effects, severe side effects, and side effects that required change in treatment. Results The study included 121 patients who were administered tenofovir and 130 patients who were administered entecavir. The majority of patients were men, with mild to moderate histology in both treatment groups. The mean duration of follow-up was 18 and 20 months for tenofovir and entecavir, respectively. Patients receiving both drugs showed comparable rates of HBeAg loss, rates of undetectable HBV-DNA levels, rates of ALT normalization, ALT decrease, and decrease in HBV-DNA. Both drugs were well tolerated. Conclusion This study shows that although the baseline characteristics did not match, tenofovir and entecavir sustained comparable virological efficacies. More patients discontinued entecavir during follow-up. Both drugs provided effective viral control, with few side effects.

The Changing Epidemiology of Bloodstream Infections and Resistance in Hematopoietic Stem Cell Transplantation Recipients

Objective: Patients receiving hematopoietic stem cell transplantation (HSCT) are exposed to highly immunosuppressive conditions and bloodstream infections (BSIs) are one of the most common major complications within this period. Our aim, in this study, was to evaluate the epidemiology of BSIs in these patients retrospectively. Materials and Methods: The epidemiological properties of 312 patients with HSCT were retrospectively evaluated. Results: A total of 312 patients, followed between 2000 and 2011, who underwent autologous (62%) and allogeneic (38%) HSCT were included in the study. The most common underlying malignancies were multiple myeloma (28%) and Hodgkin lymphoma (21.5%). A total of 142 (45%) patients developed at least 1 episode of BSI and 193 separate pathogens were isolated from the blood cultures. There was a trend of increase in the numbers of BSIs in 2005-2008 and a relative increase in the proportion of gram-positive infections in recent years (2009-2011), and central venous catheter-related BSI was found to be most common source. Coagulase-negative staphylococci (49.2%) and Acinetobacter baumannii (8.8%) were the most common pathogens. Extended-spectrum beta-lactamase-producing strains were 23% and 22% among Escherichia coli and Klebsiella spp. isolates, respectively. Quinolone resistance was detected in 10% of Enterobacteriaceae. Resistance to carbapenems was not detected in Enterobacteriaceae, while it was seen at 11.1% and 23.5% in Pseudomonas and Acinetobacter strains, respectively. Conclusion: A shift was detected from gram-negative bacteria to gram-positive in the etiology over the years and central lines were the most common sources of BSIs.

Simultaneous cryptococcal and tuberculous meningitis in a patient with systemic lupus erythematosus

Simultaneous central nervous system (CNS) infection with Cryptococcus and tuberculosis (TB) is very rare. Despite improved therapeutic options, treatment of CNS cryptococcosis is still difficult and needs invasive treatment modalities, such as intrathecal or intraventricular amphotericin B, in refractory cases. We describe a patient with systemic lupus erythematosus diagnosed with simultaneous cryptococcal and TB meningitis who had a poor response to intravenous liposomal amphotericin B and fluconazole, but was successfully treated with intraventricular amphotericin B, in addition to anti-TB therapy.