SCCmec typing and detection of VISA-related genes in methicillin-resistant Staphylococcus aureus clinical strains from Kobe University Hospital, Japan.

A total of 50 clinical strains of methicillin-resistant Staphylococcus aureus (MRSA) were collected from Kobe University Hospital in 2003. Molecular typing of SCCmec was performed by multiplex polymerase chain reaction (PCR) and the presence of six genes (vraR, vraG, vraA, vraF, fruA, and fruB) associated with vancomycin (VCM) resistance was examined by simple PCR analysis. Out of 50 MRSA strains isolated 47 strains contained Type II SCCmec and the remaining contained Type IV SCCmec. Thirty seven strains contained pUB110 plasmid. VraA was present in 69% of the strains, vraF in 10%, vraG in 53%, and vraR in 16%. Noteworthy, strains without pUB110 contained vraR in relatively higher frequency (31%) compared with strains with pUB110 (11%).

Identification and sequencing of Salmonella enterica serotype typhi isolates obtained from patients with perforation and non-perforation typhoid fever.

We describe the characterization of Salmonella enterica serovar Typhi, isolated from the blood of patients with perforation and non-perforation typhoid fever, by a combination of conventional microbiological tests, 16S rRNA gene sequencing, and flagellin gene and CDP-tyvelose epimerase (rfbE) gene sequencing. The 16S rRNA gene sequencing showed that there were four base mutations from perforation samples and only three from non-perforation samples. These findings indicated that the isolates were a strain of Salmonella enterica. The flagellin gene sequences from the two groups were 100% identical to that of the H1-d flagellin gene of serovar Typhi. Sequences of the rfbE from both groups were also 100% identical.

Antibody response in typhoid fever in endemic Indonesia and the relevance of serology and culture to diagnosis.

Culture and serology were performed on blood and serum samples collected at or shortly after admission from 473 patients presented with suspected clinical typhoid. Clinical symptoms at first presentation including confusion, hepatomegaly, splenomegaly, abdominal pain, anemia, and gastrointestinal bleeding were non-specific as they were observed even more often in non-typhoid patients. Culture confirmed the diagnosis in 65.3% of the patients with typhoid fever as the final diagnosis. The sensitivity (58%) and specificity (98.1%) of a rapid dipstick assay for the detection of S. typhi-specific immunoglobulin M were somewhat lower than those of culture but higher than those of the Widal test. The dipstick assay thus may well be used in the serodiagnosis of typhoid in situation where culture facilities are not available. Combination of test results of dipstick and culture improved sensitivity to 82.5%. In laboratories that perform blood culture the dipstick assay may be used as a rapid screening tests to facilitate a rapid diagnosis. Sensitivity of the dipstick assay strongly increased with duration of illness and was higher for culture positive than for culture negative patients. Duration of illness, and different pathogen and host factors including dose of infection, pathogenicity and antigenicity, and prior antibiotic use are likely to influence the immune response, therefore the result of the dipstick assay. Duration of illness and presence of S. typhi in the blood are major factors that determine severity of disease.