Diagnostic relevance of autoantibody detection against inhibitors of apoptosis proteins in colon cancer and colon adenoma.

Autoantibodies against cancer-related antigens may be detected in the sera of patients with various types of cancer, although their clinical utility has not yet been established. In this study, we aimed to demonstrate the diagnostic relevance of autoantibody detection against inhibitor of apoptosis protein (IAP) family members in colon cancer, as compared to anti-p53 antibody, carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9. We established an ELISA system using original recombinant proteins of IAP family members (survivin, livin and X-linked IAP) and measured the expression levels in the sera of 62 healthy donors, 250 patients with colon polyps (adenoma) and 176 patients with colon cancer. When the cutoff value was set as the mean value + 2 standard deviations in healthy donors, anti-survivin exhibited the highest positivity rate (24.4%) among IAP autoantibodies in cancer patients. Furthermore, the anti-survivin antibody exhibited a high positivity rate in early-stage carcinoma and adenoma. In the combination assay, reflecting the significantly high positivity rate of CEA in stage IV tumors, the positivity rate was highest when combining the detection of anti-survivin antibody and CEA in cancer patients (50.0%), indicating that this combination may not be useful for the diagnosis of early-stage cancers. By contrast, reflecting the complete independencE of anti-survivin and anti-p53 antibodies, the combination of detecting these two antibodies resulted in the highest positivity rate (35.6%) in early-stage disease (stage 0-I). These results suggest that the combined measurement of anti-survivin and anti-p53 antibodies may be useful for the detection of early-stage colon cancer.

Age, viral copy number, and immunosuppressive therapy affect the duration of norovirus RNA excretion in inpatients diagnosed with norovirus infection.

Norovirus is one of the leading causes of acute gastroenteritis worldwide. Although it is becoming clear that viral excretion in the stool continues even after the clinical symptoms have disappeared, the factors that determine its duration remain unknown. Between 2007 and 2009, all inpatients and medical staff at our hospital who showed symptoms of a new onset of gastroenteritis were asked to submit a sample for norovirus testing by real-time RT-PCR. One of the 273 patients included tested positive for GI norovirus, and a further 89 were positive for GII norovirus. Of these 90 norovirus-positive individuals, 76% excreted norovirus RNA in the stool for more than 7 days. The inpatient group contained more long shedders than the medical staff group (5/32 versus 1/39, P<0.05). The median viral shedding duration was 19.3 and 15.2 days for inpatients and medical staff, respectively. Among hospitalized patients, younger individuals, those with a higher viral copy number, and individuals receiving immunosuppressive therapy tended to require a longer time to eliminate the virus. These patients should therefore be monitored and managed carefully to prevent nosocomial spread of the disease.

Evaluation of spa typing for the classification of clinical methicillin-resistant Staphylococcus aureus isolates.

We evaluated the utility of typing the spa gene, which encodes protein A of Staphylococcus aureus, for analyzing methicillin-resistant S. aureus (MRSA) isolates from patients with health care-associated infections by comparing the results of spa typing with those of pulsed-field gel electrophoresis (PFGE) and multiple-locus variable-number tandem repeat analysis (MLVA). We analyzed 78 clinical MRSA isolates collected at our hospital over a period of 2 months. The clinical isolates were found to have 12 different spa types, with approximately 82% (64/78) of them being typed as t002. The same clinical MRSA isolates were classified into 15 and 19 types upon MLVA and PFGE analysis, respectively, and 19 and 28 types when spa typing was used in combination with MLVA and PFGE, respectively. The discriminatory ability of spa typing alone is low, and thus indicating that this technique is insufficient for performing the initial genotyping of MRSA in short-term epidemiological studies. Therefore, spa typing should be used in combination with MLVA or PFGE for further typing of MRSA isolates.