Scholarly record
PHENOTYPIC PROFILE OF VIRULENCE FACTORS IN MULTIRESISTANT BACTERIAL STRAINS ISOLATED FROM HOSPITALIZED PATIENTS
Abstract
Nosocomial infections have an important place in human pathology, becoming a major public health problem due to the high frequency of multiresistant strains, with afferent consequences. In the Intensive Care Units (ICU), nosocomial infections represent a constant risk due to a cumulus of factors that increase susceptibility to infections, respectively: decreased immunity due to underlying pathology, patient exposure to a series of invasive manoeuvres, poor nutritional status etc. The purpose of this study was to establish the virulence profiles of nosocomial bacterial strains isolated from localized and systemic infections in immunocompromised patients. In our study, we investigated a total of 108 samples (throat swabs, wound secretions, tracheal secretions, urine and blood), collected from patients hospitalized in 2017, both in the ICU and in other clinical departments of the Emergency Institute of Cardiovascular Diseases "Prof. CC. Iliescu". After isolation on selective culture media, the bacterial strains were identified using the VITEK II system and the antibiotic susceptibility spectrum were established according to CLSI 2017/EUCAST 2017 recommendations. The production of extracellular hydrolytic enzymes was determined by using specific growth media. The results were recorded semi-quantitatively and expressed as the ratio of the colony diameter to the diameter of the colony plus the precipitation/haemolysis zone. The bacterial invasiveness ability and adherence to HeLa cells were assessed by Cravioto?s adapted qualitative and quantitative methods. Adherence indexes and patterns were established by microscopic evaluation. The invasive capacity was evaluated using a quantitative assay of the colony forming units- CFU/ml. Our results indicate that the most common etiological agents of nosocomial infections are multiple drug-resistant (MDR) opportunistic bacteria identified as Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumanii. The MDR+ and MDR- strains were identified by conventional biochemical assays and analysed for their ability to produce soluble virulence factors (enzymes) and cell associated that are involved in bacterial cell adhesion. Our research revealed that source of isolation of the total 108 analysed strains expressed an aggregative diffusion pattern. Also, the mean values of adhesion and invasion in the MDR group were significantly higher than those observed in the non-MDR group.
Publication Impact Profile
Publication details
References10
Hernández, A. L. I. C. I. A., Yagüe, G. E. N. O. V. E. V. A., García, E. V., Simón, M. A. R. I. N. A., Moreno, L. P., Canteras, M. A. N. U. E. L., & Gómez, J. O. A. Q. U. Í. N. (2018). Nosocomial infections caused by multiresistant Pseudomonas aeruginosa (carbapenems included): predictive and prognostic factors. A prospective study (2016- 2017). Revista espanola de quimioterapia: publicacion oficial de la Sociedad Espanola de Quimioterapia.
Zhanel, G. G., DeCorby, M., Laing, N., Weshnoweski, B., Vashisht, R., Tailor, F., ... & Lagacé-Wiens, P. (2008). Antimicrobial-resistant pathogens in intensive care units in Canada: results of the Canadian National Intensive Care Unit (CAN-ICU) study, 2005-2006. Antimicrobial Agents and Chemotherapy, 52(4), 1430-1437.
Chong, Y., Shimoda, S., & Shimono, N. (2018). Current epidemiology, genetic evolution and clinical impact of extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae. Infection, Genetics and Evolution. 5(61)185-188.
Mitache, M.M., Curutiu, C., Rusu, E, Bahna, R., Ditu, L.M., Modovan, H., Hancu, V., Chifiriuc, M.C. (2017). Urinary tract infections in patients with type 1 and type 2 diabetes: Etiology, resistance to antibacterial chemicals and virulence features. Revista de Chimie, 68(3):566-569.
Climo, M. W., Yokoe, D. S., Warren, D. K., Perl, T. M., Bolon, M., Herwaldt, L. A., ... & Wong, E. S. (2013). Effect of daily chlorhexidine bathing on hospital-acquired infection. New England Journal of Medicine, 368(6), 533-542.
Chifiriuc, C., Mihaescu, G., & Lazar, V. (2011). Microbiologie si virologie medicala. Editura Universitatii, Bucharest.
Martin, G. S. (2012). Sepsis, severe sepsis and septic shock: changes in incidence, pathogens and outcomes. Expert review of anti-infective therapy, 10(6), 701-706.
Delcaru, C., Chifiriuc, M.C., Dracea, O., Iordache, C., Limban, C., Nitulescu, G.M., Missir, A.V., Chirita, I.C., Badiceanu, C., Bleotu, C., Sakizlian, R., Israil, A.M., 2012. In vitro evaluation of the influence of compounds with tricyclic structure on the microbial growth and expression of virulence factors, African J Pharmacy and Pharmacology, 6, 23, 1631-1638.
Lazar, V. (2003). Aderenta microbiana. Ed. Academiei Romane, Bucuresti.
Lamari, F., Chakroun, I., & Rtimi, S. (2017). Assessment of the correlation among antibiotic resistance, adherence to abiotic and biotic surfaces, invasion and cytotoxicity of Pseudomonas aeruginosa isolated from diseased gilthead sea bream. Colloids and Surfaces B: Biointerfaces, 158, 229-236.
View or Download full articleAccess options
SWS access login
Login as SWS Scientific CommitteeLogin as SWS Scientific PartnerLogin as SWS AuthorAuthors and approved SWS contributors will read and export their own linked papers after identity matching by SWS profile, email and SGEM GlobalID.
For librarian assistance: [email protected]
Purchase Instant Access
- Article can be downloaded after successful payment.
- Article may be used according to SWS library access terms.
- Article cannot be redistributed.
