Characterization of Ba813 harbouring Bacillus cereus in patients with haematological malignancy and hospital environments at a medical centre in Japan.

Introduction. Bacillus cereus harbouring Ba813, a specific chromosomal marker of Bacillus anthtacis, is found in patients with severe manifestations and causes nosocomial outbreaks.Aim. We assessed the genetic characteristics and virulence of Ba813(+) B. cereus in a hospital setting.Methodology. Three neutropenic patients with haematological malignancy developed B. cereus bacteraemia within a short period. Fifteen B. cereus were isolated from different sites in a haematology ward. A total of 18 isolates were evaluated for Ba813- and B. anthracis-related virulence, food poisoning-related virulence, genetic diversity, bacteria motility and biofilm formation.Results. Ba813(+) B. cereus was detected in 33 % (1/3) of patients and 66 % (9/15) of the hospital environment. The 18 strains were divided into 2 major clusters (clade 1 and clade 2), and 14 strains were classified into clade 1. All Ba813(+) strains, including four sequence types, were classified into clade 1/the cereus III lineage, which is most closely related to the anthracis lineage. Two strains belonging to clade 1/non-cereus III carried the B. anthracis-associated cap gene, but not Ba813. B. cereus, including Ba813(+) strains, had significantly lower prevalence of enterotoxin genes than clade 2 strains. In clade 1, B. cereus, Ba813(+) strains showed significantly higher swimming motility and biofilm formation ability than Ba813(-) strains.Conclusion. Ba813(+) B. cereus, which are genetically closely related to B. anthracis, were abundant in a haematological ward. Ba813(+) B. cereus with high motility and biofilm formation abilities may spread easily in hospital environments, and could become a hospital-acquired infection.

Risk factors for catheter-related bloodstream infections in adult hospitalized patients - multicenter cohort study.

BACKGROUND: Risk factors for catheter-related bloodstream infections (CRBSIs) may change over time with progress in infection control. This study was undertaken to explore the current risk factors for CRBSIs in hospitalized patients. METHODS: Adult patients with non-tunneled central venous catheters (CVCs) in 12 Japanese referral hospitals were prospectively enrolled between December 2009 and January 2012. Patients were monitored for CRBSIs for up to 8 weeks from CVC insertion; data were collected regarding patient characteristics, the purpose of CVC insertion, insertion methods, mechanical complications during insertion, and post-insertion catheter care. RESULTS: A total of 892 patients were enrolled in this study. The overall incidence of CRBSIs was 0.40 infections per 1000 catheter-days. Univariate analysis using the Fisher's exact test identified one of the participating hospitals (hospital A; p < 0.001), internal jugular vein catheterization (IJVC) (p = 0.0013), not using maximal sterile barrier precautions (p = 0.030), and the Seldinger technique for catheter insertion (p = 0.025) as significant risk factors for CRBSI. After excluding data from hospital A, only IJVC remained a significant risk factor for CRBSI (p = 0.025). The cumulative probability of remaining without CRBSI was significantly lower in patients with IJVCs than in patients with other catheter routes (p < 0.001; log-rank test). Similarly, the cumulative probability of remaining without catheter removal due to a suspected infection was significantly lower in patients with IJVCs (p = 0.034; log-rank test). CONCLUSIONS: The current study suggests that IJVC might be a risk factor for CRBSI under current infection control conditions.

Three fatal cases of rapidly progressive infective endocarditis caused by Staphylococcus aureus: one case with huge vegetation.

Staphylococcus aureus (S. aureus) infective endocarditis (IE) is a severe disease with a high mortality despite intensive therapy. Three cases of S. aureus IE had a rapidly progressive fatal clinical course despite intensive antimicrobial therapy. One case was methicillin-sensitive S. aureus IE, which formed rapidly growing a huge vegetation on a prosthetic mitral valve, complicated with multiple systemic emboli. The other 2 cases were methicillin-resistant S. aureus IE without any predisposing heart disease.

Dynamic reconstruction of large abdominal defects using a free rectus femoris musculocutaneous flap with normal motor function.

Reconstruction of large abdominal wall defects with conventional reconstruction including the component separation technique is difficult because of strong transverse tension and loss or weakness of the rectus abdominis muscle. To overcome this problem, dynamic reconstruction of the abdominal wall using a free innervated rectus femoris musculocutaneous flap was performed for large defects with separation of the bilateral rectus abdominis muscles. The intact motor nerve of the rectus femoris muscle was transferred without transection, and only the pedicle vessels were anastomosed to the omental vessels. Four and one-half years after surgery, the rectus femoris muscle had voluntary strong muscle contraction and there was no abdominal protrusion, herniation, or donor morbidity. This new method with dynamic function can replace conventional techniques for large abdominal defects without rectus muscle function.