Background: Stenotrophomonas maltophilia is a non-fermentative gram-negativebacillus which is widely recognised as an important nosocomial pathogen causing pneumonia,blood-stream, wound and urinary tract infections, particularly in immunosuppressed patients. Theaim of this study was to evaluate a nosocomial outbreak of by S. maltophilia in an intensive careunit of a tertiary hospital and evaluate unexpected multiclonality.Methods: A total of 11 isolates from respiratory cultures in intensive care unit of a 24 bedtertiary hospital obtained over a one months period and one isolate obtained from the nebuliserduring environmental screening were investigated. The bacteria were identified by Phoenix 100system. The clonal relatedness was evaluated by PFGE and semi-automated repetitive sequencebasedPCR. Genotyping tests were repeated for 10 serial subcultures.Results: PFGE and DiversiLab yielded 10 genotypic profiles for 12 isolates. Four to eightdifferent genotypes were observed from 10 subcultures of the same isolate.Conclusion: We conclude that, high genetic diversity and supposed multiclonalappearance of the outbreak isolates may be due to changing profiles during subcultures mostprobably depending on hypermutation.

Atrial septal defect (ASD) is the common congenital anomaly which requires surgical interventions. Right atrial thrombus formations after primary suture repairs of the ASD and evidences of thromboembolic complications are extremely rare. Specifically, the cases of thromboembolic complications have high mortality and morbidity risks. Two cases of giant intra-atrial thrombus formation detected in the late stage after primary repairs of ASDs are being discussed.
Heart Atria ; Heart Septal Defects ; Heart Septal Defects, Atrial* ; Mortality ; Sutures ; Thoracic Surgery ; Thrombosis*