External quality control survey on identification of microorganisms using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（ MALDI-TOF MS） is a bacterial typing tool that was approved as a medical device in 2011. However, external accuracy control examination of bacterial typing using mass spectrometry is still only performed on a small scale. In this study, E. faecium and S. maltophilia were selected and tested according to established procedures using Score Values at 228 institutions. The Score Values for MALDI Biotyper were 2.43±0.08 for E. faecium and 2.38±0.08 for S. maltophilia; and those for VITEK MS/PRIME were 99.9±0.0 for E. faecium and S. maltophilia. These results suggest that it is useful to evaluate external accuracy control with Score Values using the procedures we have developed.

Examination of Conditions for External Quality Control in Identification of Microorganisms using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was approved for medical use in 2011 and is currently used as a rapid, accurate and lowcost technique for bacterial identification. External quality control for medical analysis is monitored using tests of the Japanese Association of Medical Technologists and Prefectural Association of Clinical Laboratory Technologists and through user surveys of reagent and equipment manufacturers. However, external quality control of bacterial typing using MS is not performed. Therefore, we examined procedures for evaluating quality control of bacterial typing using an identification reliability index at 38 facilities.

Examination of conditions for regular internal quality control in identification of microorganisms using MALDI-TOF MS.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was approved for medical use in 2011, and is currently used as a rapid, accurate and low-cost technique for bacterial identification. Microbiological testing and internal accuracy control in Japan are mainly implemented in accordance with the standards of the Clinical and Laboratory Standards Institute (CLSI). However, few facilities perform internal accuracy control of bacterial identification by MALDI-TOF MS. Therefore, we examined the procedures for internal accuracy control of bacterial identification using MALDI-TOF MS in daily work at clinical laboratories in the seven hospitals.

Invasive Salmonella Enteritidis infection complicated by bacterial meningitis and vertebral osteomyelitis shortly after influenza A infection in an immunocompetent young adult.

Non-typhoidal Salmonella usually manifests as a self-limited acute gastroenteritis but may also cause severe invasive infections almost exclusively among children or immunosuppressed patients. A previously healthy 22-year-old man developed high fever with coma, multiple organ failure and shock. He had visited another hospital complaining of fever 2 days previously and was diagnosed with a common cold. No obvious site of infection was identified by radiology and a rapid test for influenza A virus was positive, indicating possible influenza-associated encephalopathy. However, blood as well as CSF culture yielded Salmonella enterica serotype Enteritidis. Therefore, the patient was considered to be suffering from bacterial meningitis with septic shock concomitant with influenza infection. Antiviral drugs and therapy for septic shock were initiated. He stabilized relatively quickly and his mental status dramatically improved. The patient denied preceding gastrointestinal symptoms, but mentioned that he received positive fecal Salmonella species culture results without medical intervention about 3 months previously. His laboratory values showed marked improvement but his elevated inflammatory markers and fever were sustained. On the 17th day of hospitalization, he complained of back pain and MRI showed lumbar vertebral osteomyelitis. This case indicates that (i) invasive Salmonella infection can be developed even in previously healthy adults; (ii) chronic carriage of Salmonella is a predisposing factor to development of invasive infections, and influenza infection may contribute to such "breakthrough infections"; (iii) attention to manifestation of metastatic extra-intestinal foci even after resolution of sepsis is necessary.

[Usefulness of survivin/glyceraldehyde-3-phosphate dehydrogenase ratio in urine exfoliated cells for the detection of bladder tumor].

OBJECTIVE: Survivin is one of the apoptosis inhibitor proteins and is rarely expressed in adult normal tissues. However, survivin expression has been detected in various tumors. In this study, we evaluated the usefulness of urinary survivin/glyceraldehyde-3-phosphate dehydrogenase (GAPDH) ratio as a marker for bladder tumor. PATIENTS AND METHODS: Urine samples were obtained from 72 patients with bladder tumor, 36 with urinary tract inflammation as controls. Survivin and GAPDH mRNA expression was measured by quantitative real-time PCR assay in urine cells. The GAPDH housekeeping gene was used for normalization of survivin expression. We also analyzed survivin protein levels using urine samples and recombinant protein by western blotting. RESULTS: High expression of survivin was confirmed on the protein level using urine samples of bladder tumor by western blotting. Survivin/GAPDH mRNA ratios of bladder tumor quantified by real-time PCR was significantly higher than those of controls (p=0.001). In pathological stage of bladder tumor, survivin/ GAPDH mRNA ratio of pTis was significantly high compared with pTa and pT1 (p < 0.001, p=0.001, respectively). Grade3 tumors expressed high level of survivin/GAPDH mRNA ratio compared with Grade 1 and Grade 2 tumors (p=0.03). The sensitivity, the specificity and AUC(area under the curve) of survivin/ GAPDH mRNA ratio was 83.3%, 86.1% and 0.898, respectively. CONCLUSION: Measuring survivin/GAPDH mRNA ratio in urine is non-invasive and high sensitive examination. Therefore, survivin/GAPDH mRNA ratio is useful marker for the detection of bladder tumor, especially to detect carcinoma in situ.

Personalized treatment in the eradication therapy for Helicobacter pylori.

Helicobacter pylori (HP) is known to be a causative bacterium of gastritis and peptic ulcers. The combination treatment consisting of a proton pump inhibitor (PPI), amoxicillin and clarithromycin (CAM) is widely used in eradication therapy, but the eradication fails in some patients. The main causes are CAM resistance of HP and individual variability in PPI metabolism related to the activity of the cytochrome P450 2C19 (CYP2C19) enzyme. In this study, we examined the usefulness of the prediction of the pharmacotherapeutic efficacy using a newly developed analysis system for HP CAM resistance and CYP2C19 genotypes. After obtaining the informed consent from 45 subjects with HP-positive peptic ulcers, biopsy specimens of the gastric mucosa were obtained by endoscopy. HP DNA extracted from the gastric mucosa was examined by the SELMAP-PCR method, the direct sequencing method or the single-nucleotide primer extension (SNuPE) method. HP detection rates by culture and the SELMAP-PCR method were 71% and 100%, respectively. Among 32 cultured HP, CAM resistance was confirmed in 6 samples by the in vitro drug susceptibility test. CAM-resistant gene mutations were also examined by the SELMAP-PCR method using 32 DNAs from cultured HP and the results were consistent with the drug susceptibility test. Among 22 patients, the eradication rate was 77%. Among 4 patients with CAM resistance determined by both the in vitro drug susceptibility test and the SNuPE method, eradication was successful in one intermediate metabolizer (IM), but not in three extensive metabolizers (EMs). Patients were divided into three groups according to their CYP2C19 phenotype: EMs, IMs and poor metabolizers (PMs). The eradication rates for 6 EMs, 12 IMs and 4 PMs were 33.3%, 91.7% and 100%, respectively. Based on these results, the information on CAM resistance in HP and CYP2C19 phenotypes in carriers could predict the pharmacotherapeutic efficacy and probability of eradication. It can then be possible to vary the dosing or to select another drug by the prediction of the pharmacotherapeutic efficacy.