Between November 2002 and March 2003, an outbreak of candiduria occurred in the surgical intensive care unit (SICU) of a university-affiliated hospital in South Korea. This outbreak affected 34 patients and was caused by Candida tropicalis. To determine the source of the epidemic and the risk factors, surveillance cultures from the SICU, genotyping of Candida isolates by pulsed-field gel electrophoresis (PFGE), and a case-control study were performed. The surveillance cultures revealed that 6 environmental samples related to the urine disposal route were positive for C. tropicalis. The PFGE analysis of genomic DNA demonstrated identical band patterns for all of the C. tropicalis isolates obtained from SICU patients and the 6 environmental samples during the outbreak period, while epidemiologically unrelated strains showed unique PFGE band patterns. Although no risk factors were identified by the case-control study, this epidemiological investigation involving the use of molecular techniques suggests that improper disposal of infectious medical waste led to the cross-transmission of a single clone that was responsible for the outbreak of C. tropicalis candiduria in this SICU. After implementing a better urine disposal system and thorough hand washing procedures, no further clusters of candiduria were detected in the SICU.

Cerebral malaria (CM) is a serious complication of Plasmodium falciparum malaria, and its pathogenesis leading to coma remains unknown. Heme oxygenase-1 (HO-1) catalyzes heme breakdown, eventually generating bilirubin, iron and carbon monoxide. The HO-1 gene promoter contains a polymorphic (GT)_n repeat which may influence the expression level of HO-1. To explore the correlation between this (GT)_n polymorphism and susceptibility to CM, we analyzed the frequencies of the (GT)_n alleles in 120 Myanmarese patients with uncomplicated malaria (UM) and 30 patients with CM. The frequency of homozygotes for the short (GT)_n alleles (<28 repeats) in CM patients was significantly higher than those in UM patinets (P < 0.008, OR = 3.14). Thus, short (GT)_n alleles represent a genetic risk factor for CM.

Since 2000, emm49-genotyped Streptococcus pyogenes strains have been isolated from patients with severe invasive group A streptococcal infections in Japan, although they had not been isolated before 1999. We compare the characteristics of these strains with those of strains isolated from patients with non-invasive infections. SmaI-digested pulsed-field gel electrophoresis profiles of the isolates were almost indistinguishable between these groups, however, we found that ska (streptokinase gene) transcriptional levels in the strains isolated from patients with severe invasive infections were significantly higher than those in non-invasive infections.

Urinary tract infection (UTI) is one of the most commonly encountered infections in childhood. It has been demonstrated that the preputial sac can act as a reservoir of organisms and is thus responsible for causing ascending UTIs. This study was performed to determine the presence of preputial flora in different age groups. Prepuce and urine samples were taken simultaneously from 92 uncircumcised and healthy male children aged between 0 - 12 years. The data were analyzed by age, with 47 subjects of 6 years of age or less, and 45 aged 7 - 12 years. Twenty-seven percent of the older patients had negative preputial cultures versus 8% of those under 6 years of age (χ² = 5.27, P = 0.02). In addition, enteric bacteria were the most common pathogens isolated from the prepuce in younger children while skin flora bacteria were most common in the older group (χ² = 9.18, P = 0.002). The urine was sterile in all cases. Preputial cultures change with age in uncircumcised boys. This change may be related to the development of immune status, to histological or anatomical changes in the prepuce, and/or to improved personal hygiene.

We assessed the antibody levels and risk factors for tetanus in an adult population in the Kocaeli Region of Turkey. In 595 individuals over 20 years of age, serum concentrations of anti-tetanus antibodies were detected by enzyme-linked immunosorbent assay and a brief questionnaire was administered. The overall immunity rate was approximately 80% and there was a progressive decline in protection with increasing age. Antibody levels were significantly higher in educated people (80.1%), in employed people (90.3%), in those under 40 years of age (95.0%) and in those who stated that they had received a previous tetanus vaccination (87.9%). There was no association between antibody level and sex, residence, socioeconomic status, military status or history of injury. These data indicate that a vigorous post-injury prophylaxy with antitoxin and antisera should be put into practice, especially for older people, and that immunization programs applied every 10 years must be strengthened.

This study is a critical analysis of certain amplification assays for detecting Chlamydia trachomatis and Neisseria gonorrhoeae infections which have demonstrated that the plasmid-free variant of C. trachomatis is frequently responsible for infection in our patients. Specifically, we evaluated the performance of the strand displacement amplification (SDA) assay in detecting either C. trachomatis or N. gonorrhoeae in 1,190 clinical samples, both urogenital and ocular, from 1,005 consecutive patients. The results obtained with the BDProbeTec^TM ET System were compared with three referenced amplification methods for C. trachomatis (detecting the 16S rRNA gene, the omp1 gene and the plasmid of C. trachomatis) and with both the culture method as well as an amplification assay followed by genetic identification performed using the MicroSeq 500 16S ribosomal DNA-based system for N. gonorrhoeae. The sensitivity of SDA (76%) in detecting C. trachomatis is significantly low when compared with that of other molecular techniques employing 16S rDNA or omp1 as a target. The specificity of the methods for detecting C. trachomatis was excellent, ranging from 99.4 to 100%. Furthermore, the results of SDA in detecting N. gonorrhoeae also provided excellent results (100% specificity and sensitivity).

Foodborne disease by Listeria monocytogenes, serovar 1/2a has recently been reported in many countries. Although contamination by this bacteria is also known to be gradually spreading among the marketed foods of Japan, there is little information on relation between listeriosis and food contamination. In the present study, the characteristics of the genomic structures of serovar 1/2a were compared among the isolates from marketed meats and listeriosis patients. Several isolates from meats purchased at the same shop on different days had the same genomic structure, and prolonged contamination was suggested by the conditions in the shop. Genomic structures of one strain isolated from meat were identical to those of two isolates from a patient. Another isolate was obtained from meats purchased at two different shops, and this isolate was also identical to that of the isolates from another patient. These findings suggest that the isolates from meat may have caused the listeriosis in the patients, and that the strains may have somehow traveled between the shops.

Detection of Japanese encephalitis virus (JEV)-specific IgM by IgM-capture enzymed-linked immunosorbent assay (IgM-capture ELISA) has been accepted as the standard for serological diagnosis. In the present study, we analyzed the time course of the positive rate of JEV-specific IgM in serum and cerebrospinal fluid (CSF) specimens from confirmed JE patients. Serum and CSF samples were obtained from 155 JE cases for diagnostic purposes at hospitals in Thailand from 2002 to 2004. The levels of specific IgM were assessed by IgM-capture ELISA in the 171 serum and 156 CSF samples. Anti-JEV IgM was detected in 26 of 44 serum samples collected on days 1 - 4 of the disease period, in 31 of 44 samples collected on days 5 - 8, in 23 of 26 samples collected on days 9 - 12, and in all the samples collected on day 13 or later. Specific IgM was detected in 60 of 66 CSF samples collected on days 1 - 4 of illness, and in all the CSF samples but one collected on day 7 or later. The results indicate that the detection of JEV-specific IgM in CSF by IgM-capture ELISA is a reliable laboratory diagnostic method for confirmation of JE throughout the disease period, while the detection of IgM in serum samples is a reliable method on day 9 or later.

In this prospective study, 93 intensive care unit (ICU)-acquired infections seen in 131 ICU patients were evaluated. Infection rates were found to be 70.9 in 100 patients and 56.2 in 1,000 patient-days. Pneumonia (35.4%) and bloodstream infections (18.2%) were the most common infections; Staphylococcus aureus (30.9%) and Acinetobacter spp. (26.8%) were the most frequently isolated microorganisms. The results of multivariate logistic regression analyses estimating the risk factors for ICU-acquired infections were as follows: length of stay in ICU (>7 days) (odds ratio [OR]: 7.02; 95% confidence interval [CI]: 2.80 - 17.56), respiratory failure as a primary cause of admission (OR: 3.7; 95% CI: 1.41 - 9.70), sedative medication (OR: 3.34; 95% CI: 1.27 - 8.79) and operation (before or after admission to ICU) (OR: 2.56; 95% CI: 1.06 - 6.18). In logistic regression analyses, age (>60 years) (OR: 3.65; 95% CI: 1.48 - 9.0), APACHE II score >15 (OR: 4.67; 95% CI: 1.92 - 11.31), intubation (OR: 3.60; 95% CI: 1.05 - 12.39) and central venous catheterization (OR: 7.85; 95% CI: 1.61 - 38.32) were found to be significant risk factors for mortality. The difference in mortality rates between patients with ICU-acquired infection and uninfected patients was not statistically significant (mortality rates: 42.3 and 45.6%, respectively). A high incidence of nosocomial infections was found, and the risk factors for ICU-acquired infections and mortality were determined.

Urinary tract infections are one of the most common infectious diseases diagnosed in outpatients as well as in hospitalized patients. Recently, urinary tract infections have become more complicated and difficult to treat. Therefore, the present study analyzed the occurrence and antimicrobial susceptibility of uropathogens isolated at Kobe University Hospital between 1983 and 2002. This study was performed with three patient groups: urology inpatients, urology outpatients, and inpatients of other departments. During the 20-year study period, we studied 15,925 urine isolates obtained from those patients who were diagnosed with urinary tract infection. Overall, Enterococcus faecalis was the most frequently isolated pathogen, followed by Pseudomonas aeruginosa and Escherichia coli. The frequency of Staphylococcus aureus increased over time, corresponding to an increase in the occurrence of methicillin-resistant S. aureus (MRSA). In addition, the rate of isolation of Serratia marcescens also increased over time, especially among patients with urinary tract catheters. Our results demonstrate that the uropathogens isolated at a single institution have shown a trend of increasing resistance to various classes of antimicrobial agents. In addition, serious problems should be anticipated in the treatment of multidrug-resistant P. aeruginosa, fluoroquinolone-resistant E. coli, and arbekacin-resistant MRSA.

The aim of this study was to use DNA sequencing analysis to analyze the mutations in the most commonly targeted genes (katG, inhA, rpoB, rpsL) in isoniazid (INH)-, rifampin (RIF)- and streptomycin (SM)-resistant Mycobacterium tuberculosis strains obtained from subjects in Düzce, Turkey. Four isolates were found to be INH-resistant, 3 were RIF- resistant and 5 were SM-resistant, out of a total of 52 M. tuberculosis strains. In 3 of the 4 INH-resistant strains, a mutation in the katG gene in codon 315 appeared as AGC→ ACC (Ser→ Thr), and the other INH-resistant strain showed a mutation in the katG gene in codon 314 as ACC→ CCC (Thr → Pro). There were no mutations in the inhA gene in INH-resistant isolates. Two of the 3 RIF-resistant strains were found to have mutations in the rpoB gene in codon 516 appearing as GAC→ GTC (Asp→ Val), and the other RIF-resistant strain has a mutation in the rpoB gene in codon 531 as TCG→ TTG (Ser→ Leu). These 3 RIF-resistant strains are also INH-resistant. All 5 SM-resistant strains have mutations in the rpsL gene in codon 43 appearing as AAG→ AGG (Lys→ Arg). Thus, we found common gene mutations that bring about the resistance of M. tuberculosis to antituberculosis drugs in all of our isolates from Düzce. To the best of our knowledge, the ACC→ CCC (Thr→ Pro) mutation in the katG gene in codon 314 has not been previously defined.

In this study, we investigated the in vivo genotoxicity of ribavirin in humans, studying 3 patients with Crimean-Congo hemorrhagic fever who were treated with high-dose ribavirin. In order to evaluate genotoxicity, both the micronucleus (MN) test and the sister chromatid exchange (SCE) test were used. In all patients, blood samples were taken during and after therapy. Whole blood cultures were performed for 72 h and the MN assay and SCE test were then carried out to demonstrate the genotoxicity. In all patients, both SCE and MN amounts were found to be higher in the samples which were taken during therapy than in those at 1 month after therapy. The results of our study reveal that ribavirin has a reversible in vivo genotoxic effect on humans.

The ehrlichial gene was detected in small rodents trapped in a Lyme disease-endemic area in Hokkaido, the northernmost island of Japan. Primer pairs of 16S rDNA targeting the genus Ehrlichia and other regions of the 16S rDNA specific for E. chaffeensis and E. muris were used for identification. The DNA fragment specific for 16S rDNA of Ehrlichia spp. was detected in 4 of 94 Apodemus speciosus mice (positive rate: 4.3%) and 5 of 73 Clethrionomys rufocanus bedfordiae mice (positive rate: 6.8%). The nucleotide sequence of the amplified 16S rDNA fragment was most similar to those of E. muris-like Ehrlichia, Ehrlichia spp. HF565 and Shizuoka-36, originating in the northern and central parts of Japan. In phylogenetic analysis based on 16S rDNA sequences, the northern, central and western groups of E. muris-like Ehrlichia from a cluster with microorganisms of the E. muris group. These results suggest that there are a group of E. muris microorganisms and a group of E. muris-like microorganisms in Japan.

Food contaminated by Listeria monocytogenes is a problem on a worldwide level because it is a serious food-borne pathogen. Although 3 evolutionary divisions have been reported for L. monocytogenes, the evolution of Japanese isolates has not yet been clarified. Thus, in order to determine the lineage of these Japanese isolates, we classified and conducted phylogenetic analysis of 407 bp (position 1116-1522) of the iap gene derived from 88 isolates from Japanese listeriosis patients, foods and environment. The isolates were classified into 18 types commonly accompanied by serotypes, and the types were divided into 3 lineages. Our results suggest that these Japanese isolates belong to the 3 lineages of L. monocytogenes isolated in other countries.

A 36-year-old, 7-week-gravida patient with catheter-related nosocomial infective endocarditis due to methicillin-resistant Staphylococcus aureus (MRSA) is presented in this paper. The patient was admitted to our hospital because of carbon monoxide intoxication. After 14 days, MRSA catheter-related bacteremia developed. The central venous catheter was immediately removed, and teicoplanin therapy was started. Because of persistent fever, leukocytosis, and high C-reactive protein values, endocarditis was suspected. A transesophageal echocardiogram revealed 19-mm vegetation on her mitral valve, confirming the diagnosis of endocarditis. Gentamicin and rifampicin were added to the therapy regimen, and the dose of teicoplanin was increased to 12 mg/kg/day. After 8 days, a splenic abscess was detected by ultrasonography. Vegetation excision, mitral valve replacement by open-heart surgery and splenectomy were performed in the same operation. Antibiotherapy was continued for 6 weeks after surgery, and the patient’s condition improved. The development of endocarditis could be prevented by proper clinical practices.