Papers by Iris Spiliopoulou
Introduction: Peritonitis is a severe complication of peritoneal dialysis (PD) due to associated ... more Introduction: Peritonitis is a severe complication of peritoneal dialysis (PD) due to associated morbidity and mortality. Although Bacillus cereus is mostly considered as a contaminant, its role as a causative agent in a few cases of PD peritonitis has been documented. Peritonitis due to B. cereus has been associated with high rates of catheter removal and resistance to beta-lactam antibiotics. Case presentation: A case of relapsing peritonitis caused by B. cereus in a 69-year-old man with end-stage renal disease on continuous ambulatory PD for 3 years is described. B. cereus was recovered from the patient’s peritoneal fluid and was identified by phenotypic and molecular methods. The patient was treated, according to the susceptibility test, with tobramycin for 14 days. Cultures became sterile and the patient was discharged from hospital. Three days after discharge, the patient reported recurrence of abdominal pain and a new antibiotic regimen based on the previous culture results w...
Archives of Disease in Childhood, 2008
Background Staphylococcus aureus causes various infections, including skin and soft tissue infect... more Background Staphylococcus aureus causes various infections, including skin and soft tissue infections (SSTIs). In this study, methicillin-susceptible S. aureu s (MSSA) from SSTIs among patients in three tertiary-care hospitals in Greece were studied in terms of antimicrobial resistance, clonal distribution, toxin and adhesin genes carriage. Results During a five-year period (2014–2018), 6145 S. aureus were recovered from 13,244 patients with SSTIs and tested for antimicrobial susceptibility. MSSA were 4806 (78.21 %) including 1484 isolates with mupirocin minimum inhibitory concentration (MIC) > 64 mg/L (30.88 %). Two hundred and sixty representative mupirocin-resistant MSSA were analyzed for genes encoding Panton-Valentine leukocidin (PVL, lukS / lukF- PV), exfoliative toxins ( eta , etb ), adhesin FnbA ( fnbA ) and resistance genes mupA (high-level resistance to mupirocin), fusB (fusidic acid), aminoglycosides’ modifying enzymes, ermA, ermC and msrA (macrolides/lincosamides) by ...
The worldwide increased bacterial resistance toward antimicrobial therapeutics has led investigat... more The worldwide increased bacterial resistance toward antimicrobial therapeutics has led investigators to search for new therapeutic options. Some of the options currently exploited to treat drug-resistant infections include drug-associated nanosystems. Additionally, the use of bacteriophages alone or in combination with drugs has been recently revisited; some studies utilizing nanosystems for bacteriophage delivery have been already reported. In this review article, we focus on nine pathogens that are the leading antimicrobial drug-resistant organisms, causing difficult-to-treat infections. For each organism, the bacteriophages and nanosystems developed or used in the last 20 years as potential treatments of pathogen-related infections are discussed. Summarizing conclusions and future perspectives related with the potential of such nano-antimicrobials for the treatment of persistent infections are finally highlighted.
Antibiotics
Background: The increased frequency of bacteraemias caused by pandrug-resistant Klebsiella pneumo... more Background: The increased frequency of bacteraemias caused by pandrug-resistant Klebsiella pneumoniae (PDR-Kp) has significant implications. The aim of the present study was to identify predictors associated with mortality of PDR-Kp bacteraemias. Methods: Patients with monomicrobial bacteraemia due to PDR-Kp were included. K. pneumoniae was considered PDR if it showed resistance to all available groups of antibiotics. Primary outcome was 30-day mortality. Minimum inhibitory concentrations (MICs) of meropenem, tigecycline, fosfomycin, and ceftazidime/avibactam were determined by Etest, whereas for colistin, the broth microdilution method was applied. blaKPC, blaVIM, blaNDM, and blaOXA genes were detected by PCR. Results: Among 115 PDR-Kp bacteraemias, the majority of infections were primary bacteraemias (53; 46.1%), followed by catheter-related (35; 30.4%). All isolates were resistant to tested antimicrobials. blaKPC was the most prevalent carbapenemase gene (98 isolates; 85.2%). Thi...
mSphere
Since the late 1990s, changes in the epidemiology of methicillin-resistant Staphylococcus aureus ... more Since the late 1990s, changes in the epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) were recognized with the emergence of community-associated MRSA (CA-MRSA). CA-MRSA belonging to clonal complex 152 (CC152), carrying the small staphylococcal cassette chromosome mec (SCCmec) type V and encoding the Panton-Valentine leukocidin (PVL), has been observed in Europe. The aim of this study was to investigate its origen, evolution, and dissemination. Whole-genome sequencing was performed on a global collection of 149 CC152 isolates spanning 20 years (93 methicillin-susceptible S. aureus [MSSA] and 56 MRSA isolates). Core genome phylogeny, Bayesian inference, in silico resistance analyses, and genomic characterization were applied. Phylogenetic analysis revealed two major distinct clades, one dominated by MSSA and the other populated only by MRSA. The MSSA isolates were predominately from sub-Saharan Africa, whereas MRSA was almost exclusively from Europe. The European MRS...
European Journal of Clinical Microbiology & Infectious Diseases
To identify the molecular characteristics of Gram-positive cocci isolated from blood cultures and... more To identify the molecular characteristics of Gram-positive cocci isolated from blood cultures and clinical outcome among critically ill patients. This retrospective study was conducted in the general intensive care unit of the University General Hospital of Patras, Greece, during a 5-year period (2012-2016). All adult patients with a Gram-positive BSI were included. PCR was applied to identify mecA gene (staphylococci); vanA, vanB, and vanC genes (enterococci). Linezolid-resistant S. epidermidis, MRSA, and VRE were further typed by multilocus sequence typing. Mutations in region V of 23S rDNA and ribosomal protein L4were investigated by PCR and sequencing analysis. The presence of the cfr gene was tested by PCR. In total, 141 Gram-positive BSIs were included. Coagulase-negative staphylococci predominated (n = 69; 65 methicillin-resistant, 23 linezolid-resistant carrying both C2534T and T2504A mutations and belonging to the ST22 clone), followed by enterococci (n = 46; 11 vancomycin-resistant carrying vanA gene, classified into four clones), S. aureus (n = 22; 10 methicillin-resistant, classified into three clones) and streptococci (n = 4). The most common type of infection was catheter-related (66; 46.8%), followed by primary BSI (28; 19.9%). Overall 14-day fatality was 24.8%. Multivariate analysis revealed septic shock as independent predictor of fatality, while appropriate empiric antimicrobial treatment and catheter-related BSI were identified as a predictor of good prognosis. Even though most of Gram-positive cocci were multidrug-resistant, fatality rate was low, associated with catheter-related BSIs. Among CNS, LR isolates represented one-third of BSIs due to the dissemination of ST22 S. epidermidis propagated by utilization of linezolid.
Respiratory Case Reports
Nondiphtherial corynebacteria commonly colonize as normal flora on human skin and mucous membrane... more Nondiphtherial corynebacteria commonly colonize as normal flora on human skin and mucous membranes, and represent an emerging opportunistic pathogen for immunocompromised or critically ill patients. Corynebacterium striatum has seldom been reported as a human pathogen. Here we present the case of a 62-year-old Caucasian female patient who was previously hospitalized in the Intensive Care Unit, and who attended the emergency department with worsening dyspnea and inspiratory wheezing. The findings of a thorough examination, laboratory tests and imaging were consistent with tracheal stenosis, inflammation related to a previous tracheostomy and a submerged thyroid goiter. A multi-drug resistant C. striatum strain was isolated. The patient was treated with a subtotal thyroidectomy, tracheal resection and tigecycline. Postoperative recovery was complicated by a trauma infection treated with open drainage and antibiotics, and after a long recovery period, the patient was discharged home without further complications.
Journal of Medical Microbiology
Purpose. To investigate the clinical, phenotypic and genotypic characteristics of Staphylococcus ... more Purpose. To investigate the clinical, phenotypic and genotypic characteristics of Staphylococcus aureus strains causing osteoarticular infections in a large paediatric series. Methodology. Medical records of children who were hospitalized with the diagnosis of community‐associated S. aureus (CA‐SA) osteomyelitis and/or septic arthritis in the two major tertiary paediatric hospitals of Athens during an 8‐year period (2007‐2015) were reviewed, and S. aureus isolates were analysed regarding antimicrobial resistance, detection of pathogenicity genes and genotyping using SCCmec, agr typing, PFGE and MLST. Results. During the study period, 123 children with CA‐SA osteoarticular infections were identified, and methicillin‐resistant S. aureus (MRSA) accounted for 44 of these (35.8 %). Children with MRSA infection had a significantly higher admission rate to the ICU (5.7 vs 0 %, P=0.04) and longer duration of hospitalization (21.6 vs 16.7 days, P=0.04). Sixty‐eight isolates [42 (methicillin‐sensitive S. aureus) MSSA and 26 MRSA] were available for molecular analysis. All MRSA strains were mecA‐positive and most carried the SCCmec IV cassette (23/26, 88 %) and belonged to the PFGE type C (24/26, 92.3 %), agr type 3 (24/26, 92.3 %) and the MLST ST80 clone (24/26, 92.3 %). In contrast, MSSA strains showed polyclonality by PFGE and agr typing. Regarding pathogenicity genes, MRSA vs MSSA isolates showed higher detection rates of PVL (96.2 vs 4.8 %, P<0.0001) and fib (80.8 vs 50 %, P=0.02). Conclusions. In our study a considerable number of S. aureus osteoarticular infections were due to CA‐MRSA isolates, most of which belonged to the ST80 clone and had a higher incidence of specific virulence factors, entailing higher ICU admission rates and a longer duration of hospitalization.
Infection, Jan 8, 2018
The aim of the present study was to analyze candidaemia's epidemiology (incidence, species di... more The aim of the present study was to analyze candidaemia's epidemiology (incidence, species distribution, and susceptibility rates) and antifungal consumption during a 9-year period. All candidaemias recorded at The University General Hospital of Patras, Greece, between 2009 and 2017 were included. Candida isolates were identified using the germ tube test, API 20C AUX System, and/or Vitek-2 YST card. Antifungal susceptibility was determined by the gradient method according to CLSI. During the study period, 505 episodes of candidaemia were observed with an overall incidence of 1.5 episodes per 1000 hospital admissions (1.1 episodes in 2009 to 1.9 in 2017: P 0.038, r 0.694). C. albicans was the leading cause (200 cases; 39.6%), followed by C. parapsilosis (185; 36.6%), C. glabrata (56; 11.1%), C. tropicalis (50; 9.9%), C. krusei (8; 0.2%), C. lusitaniae (5; < 0.1%), and C. guilliermondii (1; < 0.1%). Overall resistance to fluconazole, voriconazole, anidulafungin, caspofungin,...
The Journal of antimicrobial chemotherapy, Jan 7, 2018
We present the results of two European external quality assessments (EQAs) conducted in 2014 and ... more We present the results of two European external quality assessments (EQAs) conducted in 2014 and 2016 under the auspices of the Study Group on Staphylococci and Staphylococcal Infections of ESCMID. The objective was to assess the performance of participating centres in characterizing Staphylococcus aureus using their standard in-house phenotypic and genotypic protocols. A total of 11 well-characterized blindly coded S. aureus (n = 9), Staphylococcus argenteus (n = 1) and Staphylococcus capitis (n = 1) strains were distributed to participants for analysis. Species identification, MIC determination, antimicrobial susceptibility testing, antimicrobial resistance and toxin gene detection and molecular typing including spa typing, SCCmec typing and MLST were performed. Thirteen laboratories from 12 European countries participated in one EQA or both EQAs. Despite considerable diversity in the methods employed, good concordance (90%-100%) with expected results was obtained. Discrepancies w...
Annals of gastroenterology
The aim of the study was to investigate the effect of propranolol on systemic oxidative stress an... more The aim of the study was to investigate the effect of propranolol on systemic oxidative stress and endotoxemia in patients with liver cirrhosis and clinically significant portal hypertension evidenced by the presence of esophageal varices. Fourteen patients with liver cirrhosis and esophageal varices, not previously been treated with non-selective beta-blockers (NSBB), were prospectively started on propranolol and followed up for three months. Serum early and late lipid peroxidation products (lipid hydroperoxides [LOOH] and malondialdehyde [MDA], respectively), and endotoxin concentrations in peripheral blood were measured. Fourteen age- and sex-matched healthy individuals were used as controls. Patients with liver cirrhosis presented significantly higher systemic oxidative stress and endotoxin concentrations compared to healthy controls (P<0.001). Propranolol treatment for one month significantly reduced serum MDA (P<0.05), LOOH (P<0.01), and endotoxin levels (P<0.01) c...
Digestive diseases and sciences, Jan 7, 2018
The present study investigates the role of innate and adaptive immune system of intestinal mucosa... more The present study investigates the role of innate and adaptive immune system of intestinal mucosal barrier function in cirrhosis. Forty patients with decompensated (n = 40, group A), 27 with compensated cirrhosis (n = 27, group B), and 27 controls (n = 27, group C) were subjected to duodenal biopsy. Expression of α-defensins 5 and 6 at the intestinal crypts was evaluated by immunohistochemistry and immunofluorescence. Serum endotoxin, intestinal T-intraepithelial, and lamina propria B-lymphocytes were quantified. Cirrhotic patients presented higher endotoxin concentrations (p < 0.0001) and diminished HD5 and HD6 expression compared to healthy controls (p = 0.000287, p = 0.000314, respectively). The diminished HD5 and HD6 expressions were also apparent among the decompensated patients compared to compensated group (p = 0.025, p = 0.041, respectively). HD5 and HD6 expressions were correlated with endotoxin levels (r = -0.790, p < 0.0001, r = - 0.777, p < 0.0001, respectively)...
Polish journal of microbiology, Jan 6, 2017
Among 140 patients colonized by KPC-producing Klebsiella pneumoniae (KPC-Kp) between fourth and s... more Among 140 patients colonized by KPC-producing Klebsiella pneumoniae (KPC-Kp) between fourth and seventh day of Intensive Care Unit stay, 24 developed bacteraemia immediately after colonization. Colistin-resistance of the colonizing isolate was the factor significantly associated with early KPC-Kp bacteraemia (P < 0.001; OR 6.6, 95% CI 2.4-18.4), a worrisome finding since infections by colistin-resistant isolates is associated with increased mortality due to limited remaining therapeutic options.
Infection, 2017
The aim of the present study is to identify risk factors for development and predictors of mortal... more The aim of the present study is to identify risk factors for development and predictors of mortality of candidaemia among critically ill patients. A 1:7 case-control study was conducted during a 4-year period (2012-2015) in a Greek Intensive Care Unit (ICU). Candidaemia was confirmed by positive blood cultures. All yeasts were identified using API 20C AUX System or Vitek 2 Advanced Expert System. Epidemiologic data were collected from the ICU computerized database and patients' chart reviews. Fifty-three patients developed candidaemia with non-albicans species being the predominant ones (33 patients, 62.3%). Multivariate analysis found that prior emergency surgery, malignancy, hospitalization during summer months, prior septic shock by KPC-producing Klebsiella pneumoniae and number of antibiotics administered were independently associated with candidaemia, while, prior administration of azole was a protective factor. Non-albicans candidaemia was associated with number of antibio...
PLOS ONE
Background The correlation of Clostridium difficile infection (CDI) with in-hospital morbidity is... more Background The correlation of Clostridium difficile infection (CDI) with in-hospital morbidity is important in hospital settings where broad-spectrum antimicrobial agents are routinely used, such as PLOS ONE |
Journal of Medical Microbiology
Acinetobacter baumannii and Pseudomonas aeruginosa provoke serious infections, especially in inte... more Acinetobacter baumannii and Pseudomonas aeruginosa provoke serious infections, especially in intensive care unit (ICU) patients. The risk factors and predictors of mortality for P. aeruginosa (n=84; 46 carbapenem-resistant) and A. baumannii (n=129; all carbapenem-resistant) bloodstream infections (BSIs) in an ICU were evaluated. Antibiotic susceptibility testing was performed using the agar disk diffusion method according to EUCAST guidelines. The minimum inhibitory concentration was determined by a gradient method (Etest). Multilocus sequence typing (MLST) was performed for P. aeruginosa during the carbapenem-resistant outbreak in 2014. Epidemiological data were collected from the patients&#39; chart reviews.Results/Key findings. Hospitalization during the summer months, prior KPC-producing Klebsiella pneumoniae (KPC-Kp) BSI, and the administration of tigecycline, aminoglycosides and cortisone were independently associated with P. aeruginosa BSIs. MLST revealed the dissemination of clone ST227, including carbapenem-resistant P. aeruginosa strains. Hospitalization during the summer months, prior KPC-Kp BSI, and the administration of antibiotics, carbapenem and cortisone were independently associated with A. baumannii BSIs. The 30-day mortality rate for P. aeruginosa and A. baumannii BSI was 45.2 and 39.5 %, respectively. Sequential organ failure assessment (SOFA) score at onset, septic shock, age, and prior KPC-Kp BSI were significantly associated with P. aeruginosa BSI mortality. The administration of at least one active antibiotic was identified as a predictor of a good prognosis. Septic shock and simplified acute physiology score (SAPS) II at onset were independently associated with A. baumannii BSI mortality. The administration of at least one active antibiotic and colistin-vancomycin co-administration were identified as predictors of a good prognosis. KPC-Kp infection predisposes ICU patients to BSI by either A. baumannii or P. aeruginosa. The administration of at least one active antibiotic leads to better survival rates.
International Journal of Antimicrobial Agents, 2007
International Journal of Antimicrobial Agents, 2007
Objective: Data on the prevalence of Methicillin-Resistant Staphylococcus aureus (MRSA) carriers ... more Objective: Data on the prevalence of Methicillin-Resistant Staphylococcus aureus (MRSA) carriers in long term care facilities are lacking in Italy, being 11% the prevalence reported in the only available investigation conducted in a single facility. Aim of the study is to determine prevalence and risk factors for MRSA carriage in nursing home residents in Vicenza (North-Eastern Italy). Methods: Nasal swabs were obtained in late June-early July 2006 from residents of the two largest long term care facilities of the city. Laboratory screening for MRSA was performed by means of the MRSA Select Agar (Bio-Rad) and full antibiotic susceptibility was assessed in MRSA isolates. Demographic and clinical data, dependency, cognitive function, length of stay, current and previous antibiotic treatment, presence of medical devices, previous hospital admission, presence of infection according to Association for Professionals in Infection Control criteria were assessed in each subject on the same day of sample collection. The factors significantly associated to MRSA carriage at univariate analysis were introduced in a multiple logistic regression model, and the corresponding odds ratio (OR) with 95% Confidence Intervals (CI) were estimated. Results: Out of 570 residents nasal swabs were obtained in 551 subjects (96.7%). Among the latter, 73% were females; the mean age was 83 years (31% of residents being aged 90 or more). 118 residents (21%) had at least one hospital admission in the previous year. 63% of subjects received systemic antibiotic treatments in the previous 12 months: 37% were treated with fluoroquinolones, 26% with cephalosporins. Overall 43 MRSA carriers were detected (7.8%; CI: 5.7-10.4%). All MRSA isolates showed fluoroquinolones resistance. At logistic regression the risk of MRSA carriage was increased in patients with cancer (OR = 6.1; CI: 2.5-15.0), with previous hospitalisation (OR = 2.0; CI: 1.0−4.0), and raised with the number of previous antibiotic treatments, reaching an OR = 3.9 (CI: 1.6−9.1) in those with 3 or more treatments. Conclusion: To date the present study is the largest Italian survey of MRSA carriage in elderly people outside the hospital setting. The prevalence resulted higher than that reported from nursing homes in other European countries like Germany. Both comorbidities (cancer) and pattern of care (previous hospitalisation and antibiotic treatment) were associated with MRSA carriage.
International Journal of Antimicrobial Agents, 2007
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Papers by Iris Spiliopoulou