Simeon Metallidis
AHEPA University Hospital
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Publication
Featured researches published by Simeon Metallidis.
Journal of Chemotherapy | 2007
Simeon Metallidis; D. Topsis; John Nikolaidis; E. Alexiadou; Georgia Lazaraki; L. Grovaris; A. Theodoridou; Pavlos Nikolaidis
Abstract Penetration of levofloxacin and moxifloxacin into cancellous and cortical bone was studied using high-performance liquid chromatography (HPLC) in 16 patients who underwent routine total hip arthroplasty. Our results demonstrate a good degree of penetration into bone for both quinolones. The mean cancellous penetration was 53.86% for moxifloxacin and 54.13% for levofloxacin. The penetration into cortical bone was 41.59% and 34.26% respectively. The concentrations for both quinolones were above the minimum inhibitory concentration (MIC90s) for the most common pathogens, so they can be used for the treatment of osteomyelitis.
Journal of Antimicrobial Chemotherapy | 2011
Lemonia Skoura; Simeon Metallidis; Andrew J. Buckton; Jean L Mbisa; Dimitrios Pilalas; Evagelia Papadimitriou; Androniki Papoutsi; Anna-Bettina Haidich; Theofilos Chrysanthidis; Olga Tsachouridou; Zoe A. Antoniadou; Panagiotis Kollaras; Pavlos Nikolaidis; Nikolaos Malisiovas
OBJECTIVES To determine the contribution of transmission clusters to transmitted drug resistance (TDR) in newly diagnosed antiretroviral-naive HIV-1-infected patients in Northern Greece during 2000-07. METHODS The prevalence of TDR was estimated in 369 individuals who were diagnosed with HIV-1 infection in the period 2000-07 at the National AIDS Reference Laboratory of Northern Greece. Phylogenetic analysis was performed using a maximum likelihood method on partial pol sequences. TDR was defined in accordance with the surveillance drug resistance mutation list (2009 update). RESULTS The overall prevalence of TDR in our population was 12.5% [46/369, 95% confidence interval (CI) 9.1%-15.8%], comprising 7.6% (28/369) resistant to nucleoside reverse transcriptase inhibitors, 5.4% (20/369) resistant to non-nucleoside reverse transcriptase inhibitors and 3.3% (12/369) resistant to protease inhibitors. Dual class resistance was identified in 3.8% (14/369). Infection with subtype A was the sole predictor associated with TDR in multivariate analysis (odds ratio 2.15, 95% CI 1.10-4.19, P = 0.025). Phylogenetic analyses revealed three statistically robust transmission clusters involving drug-resistant strains, including one cluster of 12 patients, 10 of whom were infected with a strain carrying both T215 revertants and Y181C mutations. CONCLUSIONS Our findings underline the substantial impact of transmission networks on TDR in our population.
Vaccine | 2011
Helena C. Maltezou; Panagiotis Katerelos; Maria Mavrouli; Athanasia Lourida; John G. Routsias; Nicholas Spanakis; Antonios Maragos; Anastasia Tedoma; Yiannis Bassiakos; Georgios Koratzanis; Stephanos Mantagos; Simeon Metallidis; Aspasia Katragkou; Pavlos Nikolaidis; Emmanuel Roilides; Maria Theodoridou; Athanassios Tsakris
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.
Annals of the New York Academy of Sciences | 2005
M. Pape; P Kollaras; K Mandraveli; Afroditi Tsona; Simeon Metallidis; Pavlos Nikolaidis; St. Alexiou-Daniel
Abstract: The purpose of this study was to determine the seroprevalence against Bartonella henselae and Bartonella quintana among a risk group, patients with HIV infection, and to identify the epidemiological factors involved. Our data indicate that the prevalence of Bartonella infection among HIV‐infected patients is much greater than that in the healthy population of the same area and that Bartonella infection should be considered in the differential diagnosis for patients with HIV disease.
Brazilian Journal of Infectious Diseases | 2006
Simeon Metallidis; Maria Chatzidimitriou; Afroditi Tsona; Alexandros Bisiklis; Georgia Lazaraki; Eleni Koumentaki; Ahilleas Gikas; Stela Alexiou-Daniel; Pavlos Nikolaidis
OBJECTIVE Determine the prevalence of Vancomycin-resistant enterococci (VRE) colonizing the intestinal tract of hospitalized patients and define risk factors. MATERIAL AND METHODS A point prevalence survey of VRE fecal carriage was carried out among patients who stayed at a 600-bed teaching hospital for at least two days. Resistance to vancomycin was detected by the E-test method. Epidemiological data was recorded for all patients included in the study and was used for the risk factor analysis. RESULTS A total of 128 patients hospitalized for at least two days were enrolled in this investigation. Thirty-nine patients (30.5%) were colonized with vancomycin-resistant enterococci. Twenty-three of the 39 strains were identified as Enterococcus faecium, 13 were identified as Enterococcus gallinarum and three strains as Enterococcus casseliflavus. The risk factors that were significantly associated with VRE colonization included length of hospital stay (13.2 days vs. 8.6 days), age (60.7 years vs. 47.7 years) and the presence of underlying malignancies (28.2% vs. 11.2%). An association was found between VRE colonization and the use of antimicrobials with anaerobic activity, such as metronidazole, piperacillin/tazobactam and imipenem. The use of vancomycin was associated with VRE colonization in the intensive care unit. CONCLUSIONS VRE colonization must be monitored, and risk factors should be determined, because they are useful for screening hospitalized patients for VRE colonization in order to establish prevention and control measures.
Journal of the International AIDS Society | 2012
Simeon Metallidis; Dimitrios Pilalas; Lemonia Skoura; Anna-Bettina Haidich; Olga Tsachouridou; Maria Papaioannou; Theofilos Chrysanthidis; Isidora Bakaimi; Zoe A. Antoniadou; Apostolia Margariti; Nicolaos Malisiovas; Pavlos Nikolaidis
The aim of our study was to assess the extent of late presentation for HIV care in Northern Greece during the period 2000 to 2010 and to explore correlations aiming to provide guidance for future interventions.
Journal of Chemotherapy | 2010
A. Tsona; Simeon Metallidis; Nikolaos Foroglou; Panagiotis Selviaridis; Theofilos Chrysanthidis; Georgia Lazaraki; Maria Papaioannou; John Nikolaidis; Pavlos Nikolaidis
Abstract The aim of the study was to evaluate the penetration of linezolid into cerebrospinal fluid (CSF) and brain tissue after a single i.v. dose of 600 mg. The penetration of linezolid into cerebrospinal fluid and brain tissue was studied in 18 patients undergoing a neurosurgical procedure. Linezolid 600 mg i.v. was given with the induction of anesthesia. Mean concentrations of linezolid 2h after the final dose, in serum, cerbrospinal fluid and brain tissue were assayed by HPLC. CSF/serum and brain/serum ratios were 69.57% and 44.66% respectively. Concentrations of linezolid were above the MIC90s for staphylococci and streptococci. The concentrations obtained indicate good penetration of linezolid into CSF and brain tissue and support its use in the management of multidrug-resistant Gram-positive CNS infections.
Journal of Medical Virology | 2016
Apostolia Margariti; Dimitrios Chatzidimitriou; Simeon Metallidis; Dimitrios Pilalas; A. Kourelis; Evangelia Papadimitriou; Anna-Bettina Haidich; Nicolaos Malisiovas; Lemonia Skoura
Viral load testing is a valuable tool in HIV clinical care and research. Discrepancies among diverse viral load assays, especially with regard to non‐B HIV‐1 subtypes have been reported. Our study aimed to explore the impact of HIV subtype (B versus non‐B) on the agreement between CAP/CTM, v2.0 and m2000 RealTime in treated HIV patients, focusing on low viral loads (<200 copies/ml). Our findings indicate that there is a significant difference in the performance of the compared assays in the low‐viremic range and non–B subtypes, suggesting that a single assay should be used for follow‐up. J. Med. Virol. 88:724–727, 2016.
Clinical Nephrology | 2009
Simeon Metallidis; Maria Papaioannou; Bokolas G; Panagiotis Kollaras; Gogou; Pavlos Nikolaidis
Acute renal failure is a rare complication following the administration of intravenous immunoglobulin (IVIG). Only 114 cases have been reported in the literature. The exact mechanism of IVIG-associated acute renal failure remains unclear. Hereby we describe the first case of ARF in a HIV-infected patient, who received IVIG stabilized with maltose for the treatment of HIV-related thrombocytopenic purpura.
European Journal of Internal Medicine | 2008
Simeon Metallidis; Panagiotis Kollaras; Theodoros Giannakakis; Basilis Seitanidis; Theodoros Kordosis; John Nikolaidis; Apostolos I. Hatzitolios; Pavlos Nikolaidis
BACKGROUND Empirical antibiotic treatment for febrile neutropenia is well established. The best regimen is still controversial. The purpose of this study was to evaluate the efficacy, safety, and cost of a once daily high dose of ceftriaxone plus ciprofloxacin versus thrice daily ceftazidime plus amikacin in neutropenic febrile patients. METHODS Ninety-five patients with febrile neutropenia were included in a prospective, controlled, randomized, non-blind, comparative study. Patients were randomly assigned to one of the treatment groups (63 to the ceftriaxone/ciprofloxacin group and 32 to the ceftazidime/amikacin group) and evaluated as successes or failures according to defined criteria. Daily assessments were made of all patients and all adverse events were recorded. RESULTS The overall incidence of documented infections was 45.9%: 24/47 (51.1%) in the ceftriaxone/ciprofloxacin group and 10/27 (37%) in the ceftazidime/amikacin group. There was a significant difference in clinical efficacy between the groups (p=0.011) at the end of therapy. The ceftriaxone/ciprofloxacin group had an overall incidence of resolution and improvement of 95.7% in comparison to 75% in the ceftazidime/amikacin group. Thirty-nine organisms were isolated, 26 (66.67%) gram-negative and 13 (33.33%) gram-positive. There was a low incidence of adverse events in both groups. CONCLUSION The combination of a single, high dose of ceftriaxone plus ciprofloxacin daily was more effective than the standard combination of thrice daily ceftazidime plus amikacin with no significant adverse events in either group.