Avtor/Urednik		Žohar-Čretnik, Tjaša; Poljak, Mario; Juteršek, Borut; Štorman, Alenka
Naslov		Pomen uporabe PFGE v endemskih pogojih pojavljanja MRSA
Prevedeni naslov		Prudent use of PFGE in endemic situations caused by MRSA
Tip		članek
Vir		Med Razgl
Vol. in št.		Letnik 45, št. Suppl 2
Leto izdaje		2006
Obseg		str. 69-74
Jezik		slo
Abstrakt		An endemic pattern of methicillin-resistant Staphylococcus aureus (MRSA) occurrence is the most frequently observed epidemiological situation in health care institutions all over the world. The most successful containment strategy in an endemic situation is yet to be discovered. Because not much is known about the genetic structure of isolates that form an endemic, the real nature of this epidemiologic state is not understood and we are thus mostly unsuc cessful in resolving it. Molecular typing methods are needed to gain insight into this problem. As hundreds of isolates are usually isolated in such circumstances, two of the most important questions that were addressed in our study were: firstly, how extensive routine typing is needed to be able to detect epidemic MRSA strains that are introduced into health care institutions, and, secondly, how to select a representative set of isolates to follow major changes in the genetic structure of MRSA isolates present in a selected institution. Invasive isolates were selected as a representative group and compared with non-invasive isolates of MRSA. The gold standard molecular typing method for MRSA, pulsed field gel electrophoresis (PFGE), was used. All isolates from blood cultures (72 isolates) and 150 non-invasive, randomly selected isolates, recovered every two years from different clinical samples, were analyzed. In this analysis, 23 PFGE genotypes were detected. Genotype T with its 17 different subtypes prevailed in 1993. As much as 86.7% of non-invasive isolates, as well as the only isolate from blood culture, belonged to this genotype. However, it was no longer present in 1995. Genotype B with its 12 subtypes appeared in 1994. The proportion of isolates characterized as genotype B reached 100% among invasive isolates in 1994, and 60% among non-invasive isolates in 1997. Genotype A with its 18 subtypes was detected in 1995. (Abstract truncated at 2000 characters)
Izvleček		Proti meticilinu odporen Staphylococcus aureus (MRSA) se v večini zdravstvenih ustanov, ki se srečujejo s tem povzročiteljem bolnišničnih okužb, pojavlja endemsko. Še vedno ne poznamo najuspešnejšega načina obvladovanja širjenja te bakterije, ko gre za endemsko epidemiološko sliko. Ker le slabo poznamo genetsko strukturo izolatov, ki so v takšnih razmerah prisotni, v resnici ne poznamo zakonitosti razvoja in vztrajanja endemskega stanja in zato tudi ne moremo biti uspešni pri njegovem obvladovanju. Ker se običajno srečujemo s stotinami izolatov, ki jih z molekularnimi tipizacijskimi metodami ne zmoremo vseh opredeliti, smo želeli raziskati, kako katera skupina izolatov odraža genetsko strukturo celotne populacije MRSA v ustanovi. V raziskavi smo primerjali vse invazivne izolate iz obdobja od leta 1993 do vključno 2001 (skupaj 72) in po 30 naključno izbranih neinvazivnih izolatov iz vsakega drugega leta v opazovanem obdobju (skupaj 150). Opredelili smo 23 PFGE genotipov. Genotip T s 17 pripadajočimi podtipi je prevladoval v letu 1993. Pripadalo mu je 86,7% neinvazivnih izolatov in edini invazivni izolat, osamljen v tem letu. Po letu 1995 ga med izbranimi izolati nismo 69 več našli. Genotip B s pripadajočimi 12 podtipi se je pojavil v letu 1994 in dosegel vrh s 100% deležem med invazivnimi izolati v letu 1994 in 60% deležem med neinvazivnimi izolati v letu 1997. Genotip A s pripadajočimi 18 podtipi smo med izbranimi izolati prvič našli vletu 1995. V letu 2000 je s 100% deležem dosegel vrh med invazivnimi izolati in s 93% deležem vrh med neinvazivnimi izolati. Vsi trije prevladujoči sevi MRSA so se hkrati pojavili med invazivnimi in ne-invazivnimi izolati, postali prevladujoči v enakem obdobju in tudi izzveneli sočasno. Z raziskavo smo pokazali, da so si v obdobju od 1993 do vključno 2001 v ustanovi sledile tri epidemije, ki so se med seboj prekrivale in so jih povzročili trije genetsko nesorodni sevi. (Izvleček skrajšan pri 2000 znakih)
Deskriptorji		STAPHYLOCOCCAL INFECTIONS STAPHYLOCOCCUS AUREUS METHICILLIN RESISTANCE GENOTYPE