Acta Microbiologica Hellenica

ISSN: 0438-9573 (Print) – e-ISSN: 2459-4113 (Electronic)

Since 1956, Acta Microbiologica Hellenica is the official journal of Hellenic Society for Microbiology, aiming at the constant education of Biopathologists, Clinical Microbiologists as well as of every scientist involved in Laboratory and Clinical Medicine. Acta Microbiologica Hellenica is a quarterly peer-revewied journal, cited in Scopus database.

Latest Articles

Fecal microbiome transplantation as a means of multidrug resistant bacterial decolonization of the intestine

Maria Lolou1, Georgia Gioula2, Evangelia Dimitroulia1, Athanassios Tsakris1, Joseph Papaparaskevas1,3

1.Dept. of Microbiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece

2.Dept. of Microbiology, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece

3.Central Diagnostic Laboratories, Onassis Cardiac Surgery Center, Kallithea, Greece

The partial or complete imbalance of the intestinal microbiome, as a consequence of extensive antibiotic use, can establish a number of pathological conditions, including colonization with multidrug resistant bacteria, which can subsequently lead to severe infections. Therefore, the attempt to restore the microbiome to its prior condition is an approach that can be used sup_plementary to other therapeutic options. This procedure can be performed through fecal mi_crobiome transplantation (FMT), a method that is being used effectively in treating recurrent Clostridium difficile infection. Several studies have indicated that FMT can effectively eliminate the carrier status of ESBL producing Gram-negative bacteria in up to 40% of the patients. Fur_thermore, fecal transplantation was able to de-colonize patients from vancomycin-resistant Enterococcus as well as methicillin-resistant Staphylococcus aureus. In addition, this method may be a therapeutic option for antibiotic-associated hemorrhagic colitis. However, asthe application of this methodology in research protocols is very recent and the reports are scarce, more studies are required in order to establish the actual effectiveness as well as the safety of FMT in multidrug resistant bacterial de-colonization.

Key words: microbiome, dysbiosis, fecal transplantation, microbiome transplantation, multidrug resistant bacteria

PrEP (Pre-Exposure Prophylaxis) as an innovative HIV prevention strategy

Panagiotis Toumasis1, Mina Psychogiou2, Georgia Vrioni1

1.Department of Microbiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece

2.1st First Department of Medicine, ‘Laikon’ General Hospital, National and Kapodistrian University of Athens,Athens, Greece

PrEP (Pre-Exposure Prophylaxis) is an innovative HIV prevention strategy, which, although widely used in several countries, only constituted a pilot project in Greece. PrEP is defined as the administration of antiretroviral agents recommended for HIV-negative individuals who have a high risk of HIV infection. The aim of the present review is to highlight PrEP as a pre_vention treatmentstrategy that acts complementary to other risk reduction strategies. Specif_ically, clinical trial data from studies conducted during the last decade is presented and ana_lyzed. PrEP, in all subpopulation studied and with all regimens used, significantly lowers the risk of HIV infection compared to placebo used in each study, in the 90% of the cases. No serious side effects were reported, while it was established that with adherence to the pre_scribed dose, the chances of prevention are greater.

Key words: PrEP, Pre-Exposure Prophylaxis, ΗΙV Prevention

Hydrolytic activity and biofilm formation in clinical isolates of Candida albicans: the effect of changing pH and temperature

Ikram Tefiani1, Sidi Mohammed Lahbib Seddiki*1,2, Yassine Moustafa Mahdad2,3,Zahia Boucherit-Otmani1, Hidaya Fatima Zohra Touil1, Chahrazed Bessnouci2,4

1.LAPSAB Lab: Antifungal Antibiotic, Physico-Chemical Synthesis and Biological Activity, University of Tlemcen,Algeria.

2.University Center of Naâma, Algeria.

3.PPABIONUT Lab: Physiology, Physiopathology and Biochemistry of Nutrition, University of Tlemcen, Algeria.

4.Central medical biology laboratory, Public Hospital Establishment of Naâma, Algeria.

Candida albicans is the most frequently isolated opportunistic yeast in hospitals; consistently responsible for invasive fungal infections. The formation of biofilms and the activity of hy_drolytic enzymes are two major virulence factors contributing to the pathogenicity of this species. This study aimed to highlight the activity of hydrolytic enzymes in isolated strains of C. albicans which form biofilms, as well as the effect of the change in pH and temperature on their synthesis.The capacity to form biofilms was determined using the crystal violet technique. The synthesis of phospholipase was determined by the plate method using egg yolk culture medium. For the proteinase activity, agar plates containing bovine albumin serum was used. However, esterase, coagulase and hemolysin were evaluated using the opacity test, the conventional tube test and the sheep blood plaque test, respectively. In addition, phospholipase, proteinase and esterase activities were assessed under different conditions of temperature and pH. The isolated strains of C. albicans were able to form biofilms and synthesize phospholipase, proteinase, esterase, coagulase and hemolysin; the activities of these enzymes vary differently from one strain to another. C. albicans further exhibited hydrolytic activities. The interaction significance between the strains, pH and temperature depends on the type of enzymes. This draws attention to the importance of these enzymesto better understand the relationship be_tween the pathogenesis and the virulent process of this species.

Key words: Candida albicans, Biofilms, hydrolytic enzymes,temperature, pH_

The first Prenatal Group B Streptococcus (GBS) Screening in Late Pregnancy in Algerian population (Northeast Algeria)

Kamilia Belhadi1, Farouk Zohir Chayeb2, Hayat Djaara1

1.Biotechnology’s Laboratory of the Bioactive Molecules and the Cellular Physiopathology, Faculty of BiologicalSciences, Department of Biology and Living Organisms, University of Mustapha Ben Boulaid. 53 ConstantineRd, Fesdis, Batna 05078, Algeria.

2.Department of Biology and Living Organisms, Faculty of Biological Sciences, University of Mustapha BenBoulaid. 53 Constantine Rd, Fésdis, Batna 05078, Algeria.

Group B Streptococcus (GBS) can cause severe pneumonia, sepsis and meningitis in neonates and represents one of the most prevalent causes of invasive neonatal infections. Prenatal screening and prenatal antibiotic prophylaxis can prevent maternal transmission of Strepto_coccus agalactiae during delivery. The objective of this study was to determine the maternal risk of maternal carriage of group B Streptococcus over time, to offer reliable epidemiological data to the health staff working at maternity Meriem Bouatoura, Batna (Northeast Algeria) or even all maternity hospitalsin Algeria. In this prospective study, vaginal specimens (lower third) were collected from 150 pregnant women. The samples were cultured on 5% sheep blood and Chromagar Orientation. The method of confirming the identification of GBS was he agglutination test using the PASTOREX® Strep Kit. The antibiotic susceptibility testing was performed using the Kirby Bauer method. A total of 150 patients were evaluated, on average in the 34th week of pregnancy. Fifteen patients were GBS positive, a percentage rate of 10%. In conclusion, regular vaginal culture screening in the third trimester of pregnancy is warranted, as well as evaluation of risk factors and need for antibiotic administration to infants at risk.

Key words: Streptococcus agalactiae, pregnant women, Batna, Northeast Algeria

Study of fungal isolation in diabetic foot ulcers

Ioannis Daniil1, Athanasia Papazafiropoulou2, Vasiliki Mamali1, Elias Georgopoulos2, Vaia Papadouli1,Nektaria Rekleiti1, Alexandros Kamaratos2, Olympia Zarkotou1, Stavros Antonopoulos2,Andreas Melidonis2, Kate Themeli-Digalaki1

1.Microbiology Department of “Tzaneio” General Hospital of Piraeus

2.Department of Internal Medicine and Diabetes Center of “Tzaneio” General Hospital of Piraeus

Patients with diabetes mellitus(DM) and foot ulcers have an increased morbidity and mortality. The aim ofthisstudy wasto investigate the isolation of fungi in diabetic patients with foot ulcers and furthermore epidemiological and clinical characteristics ofthese patients.During the period of January 2015 – August 2019, 321 samples of foot ulcers from 185 patients with DM were cul_tured. Fungi were isolated in 27/321 (8,4%) cultures of examined foot ulcers of 23 patients (18 males, mean age ± stable deviation: 72,1 ± 9,1 years). In only one clinical sample fungi were isolated exclusively, while a polymicrobial growth was observed in the other cases. In total, 30 fungal strains were isolated, 29 of which were yeasts (27 Candida spp. and 2 Trichosporon spp.). Only one culture yielded a mold (Fusarium spp.) along with Candida parapsilosis. C. albicans was isolated in 36,7%, while in a total of 53,3% variousspecies of Candida non-albicans were devel_oped. Two different (both in genus and species) yeast strains (C. parapsilosis and Trichosporon spp.) were grown in two cultures. C. albicans wasthe predominantspeciesin thisstudy. Only 4 of the 23 patients received antimicrobial therapy (clindamycin with tetracycline or quinolone) prior to culture. In conclusion, the isolation of fungi in cultures of foot ulcers in patients withDM is not uncommon and itisindependent of previous antimicrobial administration. C. albicans was the dominant Candida species, while in total % percentage Candida non-albicans outranked C. albicans. Also, moldsshould be sought for even if yeasts are already there. Fungal foot infections in diabetic patients are associated with longer duration of DM and a high Hb1Ac, while the main risk factors are peripheral vascular disease and neuropathy.

Key words: Fungi, Diabetes Mellitus, Diabetic Foot, Foot Ulcers

An interesting case of Desulfovibrio desulfuricans bacteraemia in an immunocompromised patient

Eleni Petrou1, Aikaterini Michelaki1, Konstantinos Armenis2, Filio Nikolopoulou2, Georgios Ganteris1,Christos Michailidis2, Eleni Vagiakou1

1.Laboratory of Microbiology GNA “G. Gennimatas”

2. 1st Clinic of Internal Medicine GNA “G. Gennimatas”

Desulfovibrio spp. are Gram-negative anaerobic bacteria ubiquitously found in the environ_ment mainly in sewage, soil and water, but also in the digestive track of humans and animals as part of the intestinal flora. Identification of these species with conventional methods can be troublesome difficult and challenging as well. As a result these pathogens are not com_monly isolated by clinical samples. We report here a case of Desulfovibrio desulfuricans bac_teraemia in an immunocompromised patient.

Key words: Desulfovibrio desulfuricans, bacteraimia, anaerobic bacteria