Molecular and Phenotypic Characteristics of Methicillin-resistant Staphylococcus aureus Strains Isolated From Hospitalized Patients in Transplantation Wards

Abstract

ObjectivesHospital-acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) frequently causes therapeutic problems and provides information about the epidemiological condition of the ward. Materials and MethodsHA-MRSA isolated from patients on transplantation wards in 1991, 1994, 1996, and from 2005 to 2007 were compared using molecular methods such as restriction fragment length polymorphism–pulse field gel electrophoresis, multilocus sequence typing (MLST), multiplex polymerase chain reaction (PCR) for detection type of staphylococcal chromosomal cassette mec, and PCR for detection. ResultsThe analysis covered HA-MRSA strains, each from a different patient. All organisms were typed using molecular methods. MLST results were compared with an international base. The examined strains belonged to five different worldwide known clonal complexes: CC8 (78%), CC5 (12%), CC1 (4%), CC30 (2%), and CC51 (4%). All could be recognized as representatives of a clonal complex CC8 clones: ST239-III (sequence type 239 and SCCmec type III named EMRSA-1, -4, -11, Brasilian, Hungarian) occurred with a frequency of 35.9%, ST254-IV (EMRSA-10, Hannover) occurred in 33.3%, ST247-I (EMRSA-5,-7, Iberian) occurred in 20.5%, ST241-III (Finland-UK) occurred in 5.15%, and ST8-IV (EMRSA-2,-6) occurred in 5.15%. ConclusionThe predomination of different clones of HA-MRSA in the particular years was observed. In 1991, the EMRSA-10 (Hannover) clone predominated (53.3%). The Brasilian-Hungarian (EMRSA-1, -4, -11) clone predominated in 1994 (50%) as well as from 2005 to 2007 (41.3%), whereas in 1996 the Iberian clone was most frequent (53.9%).