Nicholas Spanakis

Frequent detection of cytomegalovirus in the intestine of patients with inflammatory bowel disease.

Background: Although a growing number of reports have described inflammatory bowel disease (IBD) complicated with cytomegalovirus (CMV) infection, there are limited molecular studies that investigate CMV genome in intestinal sections of patients with IBD. Methods: A cross‐sectional prospective study was conducted between September 2000 and June 2003 in a cohort of 85 patients diagnosed with IBD (58 with ulcerative colitis and 27 with Crohns disease) in two adult gastrointestinal referral centers in Athens, Greece. Prevalence of CMV infection was estimated by pathologic studies in intestinal sections and by molecular assays in blood and intestinal tissue samples and compared with a control group of 42 individuals with noninflammatory disease. Results: Immunohistochemical staining showed CMV antigen in 10 IBD patients (7 with ulcerative colitis; 9 with severe disease), whereas CMV antigen was not detected in any of the controls. CMV genome in both the intestinal tissue and blood was found by polymerase chain reaction in 23 (27.1%) of the total IBD patients, in 18 (31.0%) of those with ulcerative colitis, and in 5 (18.5%) of those with Crohns disease. In addition, five (5.9%) IBD patients (2 with ulcerative colitis and 3 with Crohns disease) had detectable CMV genome in their intestinal samples but not in their blood. In the control group, five (11.9%) individuals had detectable CMV genome in their blood, but only one (2.2%) in his intestine. Conclusion: Patients with ulcerative colitis had more often detectable CMV genome in their blood as well as in their intestinal tissue samples as compared with controls (P = 0.022 and P < 0.0001, respectively). However, patients with Crohns disease had more often detectable CMV genome only in their intestinal tissue samples as compared with controls (P = 0.001). Detection of CMV genome in blood or intestinal tissue was significantly associated with short duration of IBD (P = 0.0088 and 0.04, respectively) but not with age, sex, severity of the disease, activity at colonoscopy, pancolitis, administration of a specific treatment, and surgery. In this cross‐sectional prospective study, detection of CMV genome or antigen in the intestine was commonly associated with IBD.

Containment of an Outbreak of KPC-3-Producing Klebsiella pneumoniae in Italy

ABSTRACT From March 2009 to May 2009, 24 carbapenem-resistant Klebsiella pneumoniae isolates were recovered from 16 patients hospitalized in an Italian intensive care unit (ICU). All isolates contained KPC-3 carbapenemase and belonged to a single pulsed-field gel electrophoresis (PFGE) clone of multilocus sequence type 258 (designated as ST258). A multimodal infection control program was put into effect, and the spread of the KPC-3-producing K. pneumoniae clone was ultimately controlled without closing the ICU to new admissions. Reinforced infection control measures and strict monitoring of the staff adherence were necessary for the control of the outbreak.

Detection of cytomegalovirus, parvovirus B19 and herpes simplex viruses in cases of intrauterine fetal death: association with pathological findings.

There are previous indications that transplacental transmission of cytomegalovirus (CMV), parvovirus B19 (PB19) and herpes simplex virus types 1 and 2 (HSV‐1/2) cause fetal infections, which may lead to fetal death. In a prospective case–control study we examined the incidence of these viruses in intrauterine fetal death and their association with fetal and placenta pathological findings. Molecular assays were performed on placenta tissue extracts of 62 fetal deaths and 35 controls for the detection of CMV, PB19 and HSV‐1/2 genomes. Formalin‐fixed, paraffin‐embedded liver, spleen and placenta tissues of fetal death cases were evaluated histologically. Thirty‐four percent of placental specimens taken from intrauterine fetal deaths were positive for any of the three viruses (16%, 13%, and 5% positive for CMV, PB19, and HSV‐1/2, respectively), whereas only 6% of those taken from full term newborns were positive (P = 0.0017). No dual infection was observed. This difference was also observed when fetal deaths with a gestational age <20 weeks or a gestational age >20 weeks were compared with the controls (P = 0.025 and P = 0.0012, respectively). Intrauterine death and the control groups differed in the detection rate of CMV DNA (16% and 3%, respectively; P = 0.047), which was more pronounced in a gestational age >20 weeks (P = 0.03). Examination of the pathological findings among the PCR‐positive and PCR‐negative fetal deaths revealed that hydrops fetalis and chronic villitis were more common among the former group (P = 0.0003 and P = 0.0005, respectively). In conclusion, an association was detected between viral infection and fetal death, which was more pronounced in the advanced gestational age. Fetal hydrops and chronic villitis were evidently associated with viral DNA detection in cases of intrauterine death. J. Med. Virol. 80:1776–1782, 2008.

Clusters of imipenem-resistant Acinetobacter baumannii clones producing different carbapenemases in an intensive care unit

During a 2-year period (April 2005-March 2007), 31 intensive care unit (ICU) patients in a Greek hospital were infected or colonised with imipenem-resistant isolates of Acinetobacter baumannii. Twelve patients died, with imipenem-resistant A. baumannii infection contributing to the death of seven patients. The 31 representative A. baumannii isolates were multidrug-resistant and clustered in four distinct clones, each of which contained different carbapenemase genes: clone I was predominant and contained bla(VIM-1), bla(OXA-58) and the intrinsic bla(OXA-66) gene; clone II contained bla(VIM-4), bla(OXA-58) and the intrinsic bla(OXA-69) gene; clone III contained bla(OXA-58) and the intrinsic bla(OXA-69) gene; and clone IV contained only the intrinsic bla(OXA-66) gene. ISAba1 was not associated with the intrinsic bla(OXA-51-like) alleles, whereas ISAba3 was found upstream and downstream of bla(OXA-58) in isolates of clone I, and upstream of bla(OXA-58) in isolates of clone III, but was not detected in isolates of clone II. PCR, curing and hybridisation experiments indicated that the bla(VIM) alleles were chromosomally located, whereas the bla(OXA-58) alleles were plasmid-located. This study provides the first description of the clonal spread of multidrug-resistant A. baumannii isolates carrying bla(VIM-1) and bla(VIM-4) metallo-beta-lactamase genes, and revealed that distinct carbapenem-resistant A. baumannii clusters bearing different carbapenemase genes may emerge and cause severe infections, even in a well-defined regional hospital setting.

VIM-12, a Novel Plasmid-Mediated Metallo-β-Lactamase from Klebsiella pneumoniae That Resembles a VIM-1/VIM-2 Hybrid

ABSTRACT A transferable plasmid from Klebsiella pneumoniae carried a class 1 integron containing blaVIM-12, a novel blaVIM-type gene, flanked by two copies of aacA7. blaVIM-12 was clustered between blaVIM-1 and blaVIM-2 and differed from blaVIM-1 by 18 nucleotides that were all located at the 3′ end and matched the corresponding nucleotides in blaVIM-2. The blaVIM-12-associated 59-base element was identical to that described in blaVIM-2 alleles.

Large Dissemination of VIM-2-Metallo-β-Lactamase-Producing Pseudomonas aeruginosa Strains Causing Health Care-Associated Community-Onset Infections

ABSTRACT During a 3-year period (May 2005 to April 2008), a series of 45 outpatients presented with community-onset urinary tract infections due to carbapenem-resistant Pseudomonas aeruginosa isolates. Forty of them had a history of previous hospitalization or exposure to healthcare facilities, while the remaining five had not been previously admitted to our healthcare facilities or elsewhere within the preceding 12 months. In 18 outpatients, the carbapenem-resistant organisms caused recurrent community-onset urinary tract infections, while in three outpatients the organisms were also implicated in bacteremic episodes. All 45 single-patient P. aeruginosa isolates harbored the blaVIM-2 metallo-β-lactamase (MBL) gene in a common class 1 integron structure. They belonged to one predominant pulsed-field gel electrophoresis type and three sporadically detected types; two of the sporadic clonal types were identified among outpatients without previous exposure to healthcare facilities, while the predominant clonal type was also identified to cause infections in hospitalized patients. This is the first study documenting that MBL-producing P. aeruginosa isolates cause community-onset infections that are related or not with exposure to healthcare facilities. Community-onset infections in our patients most likely resulted from the nosocomial acquisition of MBL producers, followed by a prolonged digestive carriage. The high rate of recurrent infections in the community underlies the difficulty of constraining infections caused by such microorganisms in the extrahospital setting.

Adenovirus genome in the placenta: association with histological chorioamnionitis and preterm birth

Adenovirus is isolated frequently from the amniotic fluid and has been implicated in severe neonatal infections. A case control study was carried out to examine the association of detection of adenovirus in placentas with preterm birth and histological chorioamnionitis. Placentas from preterm and full term deliveries were collected prospectively. Preterm cases were divided into three subgroups according to the gestational age. PCR was carried out on placental tissues for the detection of adenovirus genome. Placentas were evaluated histologically for the presence of chorioamnionitis. Chi‐square and odds ratios (OR) were used to determine if detection of adenovirus is associated with preterm birth and histological evidence of inflammation. Seventy‐one preterm and 122 full term placentas were studied. Adenovirus genome was detected in 29 (40.8%) of preterm cases and in 25 (20.5%) of the full term controls (OR = 2.6; 95% CI, 1.4–5.1; P = 0.002). Detection of adenovirus in preterm placentas was significantly higher compared to full term particularly in the lower gestational age. Detection of adenovirus in placenta followed the seasonal variation of adenovirus infections. Thirty‐seven preterm and 21 full term placentas were also selected for paraffin inclusion and histological examination. Chorioamnionitis was present more frequently in preterm adenovirus‐positive placentas compared to preterm adenovirus‐negative placentas (75% vs. 36%; P = 0.026) as well as compared to term adenovirus‐positive placentas (75% vs. 19%; P = 0.003). This study demonstrates that adenovirus infection of the placenta is associated strongly with histological chorioamnionitis and preterm birth. J. Med. Virol. 82:1379–1383, 2010.

Tissue concentration of transforming growth factor β1 and basic fibroblast growth factor in skin wounds created with a CO2 laser and scalpel: A comparative experimental study, using an animal model of skin resurfacing

Although a number of ablative‐laser techniques based on CO2 and Er: YAG laser devices have been successfully developed and used in the clinical setting, the bio‐molecular processes influencing wound healing after exposure to laser energy are not well elucidated. In this study, we aim to assess the impact of the mechanism of injury on the secretion of transforming growth factor β1 (TGF‐β1) and basic fibroblast growth factor (bFGF) in various stages of wound healing, in wounds created with a CO2 laser and scalpel. Ten Wistar rats were used to determine the levels of growth factor proteins TGF‐β1 and bFGF after CO2 laser‐ and scalpel‐induced skin injury. Tissue was excised on day 0 for untreated skin (control sites), and on days 1, 10, 30, and 90 following laser and scalpel surgery. Specimens were processed for histopathological analysis and for determining the concentration of growth factors by a Western blot technique. The concentration of TGF‐β1 increased markedly, at day 1 postinjury, from a baseline of 130±16 mm2 (mean surface area of blotted‐protein lanes) to 261±23 mm2 and 394±22 mm2 for laser‐inflicted injury and scalpel wounds, respectively; the latter values were found to differ significantly (p<0.001). The concentration of b‐FGF on day 10 postinjury differed significantly (p<0.001) between the laser sites (553±45 mm2) and the corresponding scalpel sites (418±41 mm2). Laser energy alters local tissue secretion of TGF‐β1 and bFGF of skin injuries created with the CO2 laser compared with wounds created with a scalpel. These differences might have an impact on various aspects of wound healing of skin injuries created by a laser.

Current perspectives on tigecycline resistance in Enterobacteriaceae: susceptibility testing issues and mechanisms of resistance

During the past decades, rates of multidrug-resistant (MDR) and carbapenem-resistant (CR) Enterobacteriaceae clinical isolates, mainly Klebsiella spp., Escherichia coli, Enterobacter spp., Proteus spp. and Serratia marcescens, have increased, considerably restricting effective antimicrobial treatments. Tigecycline, the first member of the glycylcyclines, has been approved by the US Food and Drug Administration (FDA) for the treatment of complicated skin and soft-tissue, complicated intra-abdominal and community-acquired bacterial respiratory infections and is increasingly administered against MDR Enterobacteriaceae. Although resistance has gradually appeared, tigecycline still remains relatively active among Enterobacteriaceae, with resistance rates largely <10% in most wide-scale surveillance studies. Tigecycline resistance has been reported in some studies to be elevated among extended-spectrum β-lactamase (ESBL)-producing, MDR, extensively drug-resistant and CR isolates. Broth microdilution (BMD) is the reference method for tigecycline susceptibility testing, but disagreements have been reported between the methods applied for routine tigecycline susceptibility testing. Therefore, confirmation of daily tigecycline susceptibility testing with BMD appears important in order to avoid misclassification of isolates. Various mechanisms have been reported to confer tigecycline resistance, with RND-type transporters, mainly the AcrAB efflux pump, playing an important role. Other pumps and various control pathways are also implicated in tigecycline resistance. Overall, tigecycline is a potent therapeutic option for enterobacterial infections. Accurate detection of tigecycline susceptibility status and surveillance of resistant organisms in the hospital environment is necessary in order to optimise its use and to preserve tigecycline in our therapeutic arsenal.

Seroepidemiological study of pandemic influenza H1N1 following the 2009-2010 wave in Greece.

Knowledge of seroprevalence rates against 2009 pandemic H1N1 virus will assist vaccination recommendations and the preparation of the health-care system during subsequent years. This study was conducted in Greece during June-August 2010 to estimate the seroprevalence rate against pandemic H1N1 virus. Persons presenting in 29 health-care facilities across the country were studied. Seroprevalence was estimated employing a virus-free ELISA that specifically recognizes 2009 H1N1 virus antibodies in human sera. Sera collected from 2005 to April 2009 were also used to estimate pre-pandemic seroprevalence rates. A total of 954 persons were studied. The overall seroprevalence rate was 28.5% (95% confidence interval=25.6-31.3%). Age-specific rates were 34.2% in persons 0-4 years, 36.3% in persons 5-19 years, 25.0% in persons 20-39 years, 23.4% in persons 40-59 years, and 31.8% in persons ≥ 60 years. The highest rates were recorded in the Regions of Ionian Islands (67%) and Epirus (42.9%), while the lowest (8.4%) in the Region of Thessaly. Age-specific attack rates of infection during 2009-2010 were 28.8% in persons 0-4 years, 32.5% in persons 5-19 years, 14.3% in persons 20-39 years, 19.1% in persons 40-59 years, and 14.4% in persons ≥ 60 years. Multivariate analysis revealed that Region of residence and caring for children <5 years were associated with increased risk for seropositivity. Urbanity, personal and family characteristics, working in a health-care facility or in a school, history of pandemic H1N1 vaccination or history of influenza-like illness during 2009-2010 were not associated with increased risk for seropositivity.