Symeon Metallidis
Aristotle University of Thessaloniki
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Publication
Featured researches published by Symeon Metallidis.
International Journal of Infectious Diseases | 2013
Symeon Metallidis; Olga Tsachouridou; Lemonia Skoura; Pantelis Zebekakis; Theofilos Chrysanthidis; Dimitris Pilalas; Isidora Bakaimi; Panagiotis Kollaras; Georgios Germanidis; Aikaterini Tsiara; Antonios Galanos; Nikolaos Malisiovas; Pavlos Nikolaidis
OBJECTIVES HIV prevalence among older people is on the increase. The aim of this study was to evaluate the epidemiological and clinical features at diagnosis and survival of older patients. METHODS This was a retrospective analysis of the data of 558 newly diagnosed antiretroviral-naïve patients between January 1998 and December 2008. Patients were divided into two groups according to their age at diagnosis: ≥50 years (n=103) and 18-49 years (n=455). RESULTS The most common risk factor for older patients was heterosexual contact (p<0.013). Older patients were more likely to suffer from hypertension (33.0% vs. 5.1%, p<0.0005), cardiovascular disease (20.4% vs. 2.9%, p<0.0005), neurological disorders (11.7% vs. 5.5%, p=0.02), renal dysfunction (12.6% vs. 5.3%, p=0.01), and infections (66.0% vs. 49.7%, p=0.003) than their younger counterparts, and to have more hospital admissions during follow-up (47.5% vs. 19.6%, p<0.0005). Older patients had a shorter survival time (p<0.0005). A statistically significant increase in CD4+ cell number through time was observed in both groups (p<0.0005). Younger patients reached higher magnitudes of absolute numbers of CD4+ cells during follow-up (p<0.0005) after the initiation of antiretroviral therapy. The total number of patients with clinical AIDS from baseline throughout the study period was also higher in the older age group (35.9% vs. 25.0%). CONCLUSIONS HIV-infected people aged ≥50 years differ in epidemiological and clinical features to younger HIV-infected people. The issue of increasing prevalence of HIV infection is a matter of concern due to existing comorbidities, which probably lead to higher mortality rates and faster progression to clinical AIDS.
Clinical Microbiology and Infection | 2013
Lemonia Skoura; Symeon Metallidis; Dimitris Pilalas; A. Kourelis; Apostolia Margariti; Evagelia Papadimitriou; Zoe A. Antoniadou; Theofilos Chrysanthidis; Olga Tsachouridou; Panagiotis Kollaras; Pavlos Nikolaidis; Nicolaos Malisiovas
We conducted a retrospective study on the prevalence and correlates of transmitted drug resistance among newly-diagnosed antiretroviral naive human immunodeficiency virus (HIV) patients in Northern Greece, during the period 2009-11. Transmitted drug resistance was documented in 21.8% of patients enrolled, affecting approximately 40% of subtype A HIV-1-infected individuals. Overcoming challenges due to the ongoing financial crisis, effective preventive measures should be implemented to control further dissemination of resistant HIV strains.
Cardiovascular Ultrasound | 2009
Christos Pliakos; Eleni Alexiadou; Symeon Metallidis; Theodossis S. Papavramidis; Stergios Kapoulas; Konstantinos Sapalidis; Pavlos Nikolaidis
In this case report we describe a rare case of right atrium myxoma that coexisted with antiphospholipid syndrome in a young woman. We describe the unusual findings and diagnostic challenges combined with a review of the literature.
Diabetes Therapy | 2018
Marianthi Papagianni; Symeon Metallidis; Konstantinos Tziomalos
Accumulating evidence suggests that diabetes mellitus (DM) represents an important risk factor for both herpes zoster and post-herpetic neuralgia. Moreover, post-herpetic neuralgia appears to be more severe and persistent in diabetic patients. On the other hand, a novel vaccine against varicella-zoster virus (VZV) was recently introduced in clinical practice. Given the increased risk and severity of herpes zoster infection in patients with DM, this vaccine might be useful in this population. However, there are limited data regarding the efficacy and safety of vaccination against herpes zoster in the diabetic population. The aim of the present review is to discuss the incidence and consequences of herpes zoster infection in DM and to comment on the role of vaccination against VZV in these patients.
International Journal of Infectious Diseases | 2015
Olga Tsachouridou; Lemonia Skoura; Pantelis Zebekakis; Apostolia Margariti; Michael Daniilidis; Nikolaos Malisiovas; Symeon Metallidis
BACKGROUND Chronic HIV infection leads to severe perturbations of the B cell populations and hypo-responsiveness to vaccines. The associations between circulating B cell subpopulations and the antibody response to pneumococcal polysaccharide vaccine in antiretroviral-naïve and treated patients were studied. METHODS Sixty-six HIV-infected adults were grouped according to antiretroviral therapy (ART) and CD4+ cell count; 31 were ART-naïve and 35 were ART-treated, and they were matched for age, CD4 cell count, and duration of HIV infection. All subjects were immunized with the 23-valent polysaccharide vaccine against Streptococcus pneumoniae. Pre- and post-vaccination B cell subpopulations were assessed by flow cytometry. Serum IgG concentrations for vaccine serotypes were quantified by ELISA at baseline and at 4 and 48 weeks post-vaccination. RESULTS Patients under highly active antiretroviral therapy (HAART) had significantly higher antibody levels against pneumococcal vaccine antigens, while an adequate number of patients responded to vaccination. Memory B cells were diminished over time, although treated patients maintained higher levels of all subsets studied, with the exception of activated memory and isotype-switched memory B cells. CONCLUSIONS Low concentrations of total B cells and exhausted memory B cells was the strongest independent predictor of poor pneumococcal vaccine responsiveness, emphasizing that B cell subset disturbances are associated with a poor vaccine response among HIV-infected patients.
PLOS ONE | 2017
Athanasios Skoutelis; Angelos Pefanis; Sotirios Tsiodras; Nikolaos V. Sipsas; Moyssis Lelekis; Marios Lazanas; Panagiotis Gargalianos; George N. Dalekos; Emmanuel Roilides; George Samonis; Efstratios Maltezos; Dimitrios Hatzigeorgiou; Malvina Lada; Symeon Metallidis; Athena Stoupis; Georgios Chrysos; Lazaros Karnesis; Styliani Symbardi; Chariclia V. Loupa; Helen Giamarellou; Ioannis Kioumis; Helen Sambatakou; Epameinondas V. Tsianos; Maria Kotsopoulou; Areti Georgopali; Klairi Liakou; Stavroula Perlorentzou; Stamatina Levidiotou; Marina Giotsa-Toutouza; Helen Tsorlini-Christoforidou
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 in Greece. The C. DEFINE study aimed to assess point-prevalence of CDI in Greece during two study periods in 2013. Methods There were two study periods consisting of a single day in March and another in October 2013. Stool samples from all patients hospitalized outside the ICU aged ≥18 years old with diarrhea on each day in 21 and 25 hospitals, respectively, were tested for CDI. Samples were tested for the presence of glutamate dehydrogenase antigen (GDH) and toxins A/B of C. difficile; samples positive for GDH and negative for toxins were further tested by culture and PCR for the presence of toxin genes. An analysis was performed to identify potential risk factors for CDI among patients with diarrhea. Results 5,536 and 6,523 patients were screened during the first and second study periods, respectively. The respective point-prevalence of CDI in all patients was 5.6 and 3.9 per 10,000 patient bed-days whereas the proportion of CDI among patients with diarrhea was 17% and 14.3%. Logistic regression analysis revealed that solid tumor malignancy [odds ratio (OR) 2.69, 95% confidence interval (CI): 1.18–6.15, p = 0.019] and antimicrobial administration (OR 3.61, 95% CI: 1.03–12.76, p = 0.045) were independent risk factors for CDI development. Charlson’s Comorbidity Index (CCI) >6 was also found as a risk factor of marginal statistical significance (OR 2.24, 95% CI: 0.98–5.10). Median time to CDI from hospital admission was shorter with the presence of solid tumor malignancy (3 vs 5 days; p = 0.002) and of CCI >6 (4 vs 6 days, p = 0.009). Conclusions The point-prevalence of CDI in Greek hospitals was consistent among cases of diarrhea over a 6-month period. Major risk factors were antimicrobial use, solid tumor malignancy and a CCI score >6.
Current HIV Research | 2017
Olga Tsachouridou; Lemonia Skoura; Dimitris Chatzidimitriou; Apostolia Margariti; Maria Chatzidimitriou; Dimitrios Bougiouklis; Pantelis Zebekakis; Symeon Metallidis
BACKGROUND Phagocytosis is regarded to be impaired in HIV-1 infected adults, leading to high frequency and severity of several infections in this population. Data is contradictory with regards to individual facets in HIV infection. OBJECTIVE Aim of this study was to assess the phagocytic activity during the natural course of HIV infection. METHOD It is a longitudinal study assessing natural course and impairment of neutrophil and monocyte phagocytosis in both naïve and HAART treated patients. RESULTS A lower neutrophil phagocytic activity was recorded in naïve patients compared to treated patients. Interestingly, a downward trend of neutrophil phagocytic activity was recorded in both groups, irrespectively of HAART intake, within 48 weeks of observation. CONCLUSION Defects of innate immunity appear to be present in HIV infected patients regarding phagocytic activity of monocytes and of neutrophils which seems to decline over time. These deficiencies are influenced by the levels of CD4 cell counts and viral load.
Critical Reviews in Microbiology | 2015
Melina Kachrimanidou; Theopisti Sarmourli; Lemonia Skoura; Symeon Metallidis; Nikolaos Malisiovas
Abstract Clostridium difficile infection (CDI) is an important cause of mortality and morbidity in healthcare settings and represents a major social and economic burden. The major virulence determinants are large clostridial toxins, toxin A (TcdA) and toxin B (TcdB), encoded within the pathogenicity locus. Traditional therapies, such as metronidazole and vancomycin, frequently lead to a vicious circle of recurrences due to their action against normal human microbiome. New disease management strategies together with the development of novel therapeutic and containment approaches are needed in order to better control outbreaks and treat patients. This article provides an overview of currently available CDI treatment options and discusses the most promising therapies under development.
Current Pharmacology Reports | 2018
Marianthi Papagianni; Symeon Metallidis; Konstantinos Tziomalos
Purpose of the ReviewIn recent years, cardiovascular diseases (CVD) have become a leading cause of death in patient with HIV infection, despite a reduction of total mortality in this population. Patients with HIV who are receiving antiretroviral therapy (ART) have approximately 1.5–2 times higher risk for cardiovascular events than HIV-uninfected people. Dyslipidemia is a major risk factor for CVD and is more prevalent in patients with HIV infection. In the present review, we summarize the current concepts in the management of dyslipidemia in patients with HIV infection.Recent FindingsSeveral studies evaluated the safety and effectiveness of statins in the management of dyslipidemia in patients with HIV infections. However, most studies are small and short term and none evaluated the effects of statins on cardiovascular morbidity. There are also very limited data on the role of other lipid-lowering agents in these patients. Moreover, the effect of switching ART on the lipid profile and on viral suppression is also unclear.SummaryManagement of dyslipidemia in patients with HIV infection is complicated by the increased risk for pharmacokinetic interactions between lipid-lowering agents and ART as well as by the adverse metabolic effects of most classes of ART. However, given the increased cardiovascular risk of this population, lipid-lowering treatment, primarily with statins, should be considered and appears to be equally effective as in non-HIV infected subjects.
Journal of Medical Case Reports | 2017
Olga Tsachouridou; Sideris Nanoudis; Theofilos Chrysanthidis; Georgia Loli; Petros Morfesis; Pantelis Zebekakis; Symeon Metallidis
BackgroundThe incidence of infectious spondylodiscitis has been increasing over the last few years. This reflects the expanding elderly and immunocompromised populations and the rising implementation of invasive spinal procedures. Infection may be inoculated into the disc space directly during invasive spinal procedures. Osteomyelitis caused by Acinetobacter species is rare and mainly caused by multidrug-resistant strains.Case presentationWe present the case of a 72-year-old Greek woman with postoperative spondylodiscitis caused by a multidrug-resistant Acinetobacter baumannii strain that was successfully treated, after she declined surgical treatment, with prolonged and high dosage of tigecycline. She received intravenously administered tigecycline 200 mg per day for 60 days and then 100 mg per day for a total of 102 days and was infection-free.ConclusionsWe reviewed the literature on the role of Acinetobacter baumannii as a cause of osteomyelitis, emphasizing the difficulty of treatment and the potential role of tigecycline in conservative treatment of the infection. We believe that 102 days in total is the longest time that any patient has received tigecycline in the literature, thus our patient is a unique case of successful treatment of spondylodiscitis.