A new local variant (ST764) of the globally disseminated ST5 lineage of hospital-associated methicillin-resistant Staphylococcus aureus (MRSA) carrying the virulence determinants of community-associated MRSA.

The ST5 lineage of methicillin-resistant Staphylococcus aureus (MRSA) is one of the most globally disseminated hospital-associated MRSA (HA-MRSA) lineages. We isolated a new local variant (designated ST764) over at least 5 years that causes invasive infections, including necrotizing fasciitis, and is carried by medical students, as well as household members. Analysis of the genome sequence of one isolate compared to that of the reference ST5 strain revealed that ST764 had acquired virulence traits similar to those of community-associated MRSA (CA-MRSA) through the acquisition of two new mobile genetic elements, ACMEII and SaPInn54, which carried ACME arcA and the staphylococcal enterotoxin B gene (seb), respectively, and through enhanced expression of cytolytic peptide genes, although ST764 was negative for Panton-Valentine leukocidin. Other differences between ST764 and ST5 included the acquisition of an ACMEII-related cassette (cJR1), prophage φ2NN54, and streptococcal Tn5251 and decreased numbers of copies of Tn554. As for superantigen genes, although the two possessed seg, sei, sem, sen, and seo, ST764 lacked tst, sec, sel, and sep. The data suggest that ST764 MRSA is a novel hybrid variant of ST5 HA-MRSA with the characteristics of CA-MRSA and that the evolution of ST764 includes multiple steps, e.g., acquisition of novel or nonstaphylococcal mobile elements.

[Usefulness of the new version 3.02 of Vigileo monitor for anesthetic management in anaphylactic shock: a case report].

We studied the utility of Vigileo monitor for grasping hemodynamics with a patient in a state of anaphylactic shock. The stroke volume variation (SVV) predicts fluid responsiveness of normal cases. In the anaphylactic shock resulting from biased blood distribution, not only blood pressure but also pulse pressure markedly decreased within a couple of minutes. SVV is calculated from the standard deviation of pulse pressure. Therefore the SVV could be overestimated during anaphylactic shock. A former version of Vigileo monitor underestimated the arterial pressure-based cardiac output (APCO) due to the underrating of a single stroke volume (SV) in a range of systemic vascular resistance (SVR) below 800 dyne x sec(-1) x cm(-5). The version 3.02 Vigileo monitor allowed for more accurate estimation of SV because its new algorithm was able to revise the apparently low SVR derived from the arterial waveform characteristics and hence provided more realistic SV and APCO values. It was thus concluded that this ver. 3.02 is useful for anesthetic management of the anaphylactic case.

[Two cases of medicinal treatment of diabetic post treatment painful neuropathy].

Painful diabetic neuropathy is a common, difficult-to-manage complication of diabetes. We report two case of intractable painful diabetic neuropathy which occurred after the rapid lowering of blood sugar level. Although pregabalin, antidepressants, opioid analgetics and various nerve block did not improve their pain, clomipramine dramatically reduced their pain.

Super-sticky familial infections caused by Panton-Valentine leukocidin-positive ST22 community-acquired methicillin-resistant Staphylococcus aureus in Japan.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA), which often produces Panton-Valentine leukocidin (PVL), is an emerging threat in the community. In Japan, for example, PVL-positive ST8 CA-MRSA (USA 300), which originated from the United States, persisted in families for a year and caused severe invasive infection in a child. In this study, we describe a long-term familial infection cluster caused by novel PVL-positive CA-MRSA, which most probably originated from India. This MRSA persisted in related families for more than 2 years with colonization of, for example, the nares and cheek. At least 6 of 12 members (50%) developed deep cutaneous abscesses, including recurrent and multifocal abscesses, every 1.2 months on average. All MRSA isolates from colonization and abscesses were the same, albeit with a variant in pulsed-field gel electrophoresis analysis. The MRSA exhibited the genotype ST22/spa113(t005)/SCCmecIVa/coagulase gene (coa) novel type and strong hemolysis activity. Moreover, the MRSA exhibited high biofilm formation (which was markedly enhanced by sub-MICs of oxacillin). Some patients were treated with levofloxacin, with successful MRSA eradication even from the whole body surface sites; however, short-term patient follow-up was not sufficient to demonstrate eradication of the familial infection cluster. The data suggest that PVL-positive novel ST22 CA-MRSA emerged in Japan, causing a long-term familial infection cluster, and that the success of ST22 CA-MRSA as both a colonizer and a pathogen could result from the combination of its strong biofilm formation and other virulence factors. A long-term patient (or carrier) follow-up is needed in the community.

Bullous impetigo in children infected with methicillin-resistant Staphylococcus aureus alone or in combination with methicillin-susceptible S. aureus: analysis of genetic characteristics, including assessment of exfoliative toxin gene carriage.

Among bullous impetigo isolates, exfoliative toxin (ET) gene carriage was found in 61.5% of methicillin-resistant Staphylococcus aureus (MRSA) isolates versus 90.6% of methicillin-susceptible S. aureus (MSSA) isolates. MRSA-only cases were ETB or ETA positive, while MRSA/MSSA coinfection cases were ET negative for MRSA but ETA positive for MSSA. Collagen adhesin may facilitate some MRSA infections.

Molecular characteristics of the Taiwanese multiple drug-resistant ST59 clone of Panton-Valentine leucocidin-positive community-acquired methicillin-resistant Staphylococcus aureus from pediatric cellulitis.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA), which often produces Panton-Valentine leucocidin (PVL), has emerged worldwide as a life-threatening pathogen. Herein, we describe molecular characteristics of MRSA isolated from abdominal cellulitis in a 7-year-old Japanese boy. This MRSA was PVL-positive and belonged to the Taiwanese multiple drug-resistant CA-MRSA clone with the genotype of ST59, staphylococcal cassette chromosome mec (SCCmec) VII (SCCmecV, according to recent reclassification), agr1a (a novel agr1 subtype), and SaPI (which carried seb1, a newly designated variant seb gene). This study demonstrates the first isolation of the Taiwanese PVL-positive ST59 MRSA clone in Japan. The data also demonstrate novel subtypes in agr1 and seb and suggest that a combination of agr1a, seb1, and PVL could contribute to cellulitis (and its recurrence). Recently, a variety of PVL-positive MRSA clones are accumulating in Japan.

Sick Students: Presenteeism Among Nursing Students in 3 Countries.

BACKGROUND: Presenteeism, the act of going to work while sick, is associated with increases in medication errors, patient falls, diminished quality of care, and higher costs. To date, presenteeism has not been described among nursing students. PURPOSE: This study described presenteeism in nursing students from 3 different international nursing programs. METHOD: A self-administered survey with open-ended responses was used. RESULTS: While nearly all student respondents believed going to class and clinical experiences put their classmates and patients at risk, the overall presenteeism rate was 85.5% for class and 69.5% for clinical experiences. Although there were significant differences between universities for reasons for presenteeism, a lack of opportunity for making up missed lecture or clinical time predominated. CONCLUSION: Nursing students in 3 culturally different cities reported going to class and clinical experiences while sick despite recognizing the safety risk.

Streptococcus pneumoniae and Haemophilus influenzae at the initial stage of influenza.

BACKGROUND: Streptococcus pneumoniae and Haemophilus influenzae infections in children with influenza have been noted because of the severity of co-infection. In Japan, vaccination against S. pneumoniae and H. influenzae infections has been listed in the vaccine program in 2008, but the characteristics of the two organisms, colonizing at the initial stage of influenza infection, have not been investigated in detail. METHODS: Nasopharyngeal swabs from children with influenza (flu(+)) (n= 236; mean age, 6.2 years) were examined for bacterial pathogens, including S. pneumoniae and H. influenzae. They were then examined for serotypes, drug susceptibilities, and resistance genes (or gene mutations). As a reference, children with upper respiratory tract infection (URTI(+), flu(-); n = 189; mean age, 6.2 years) were also examined. RESULTS: S. pneumoniae, beta-streptococci (groups A, B, and G), methicillin-susceptible and -resistant S. aureus, Moraxella catarrhalis, and H. influenzae were isolated. For S. pneumoniae, nine serotypes were detected with prevalent types of 3, 6, 19 and 23. Penicillin resistance was detected in types 19 and 23, while resistance to macrolide and clindamycin was found in various types. For H. influenzae, only b serotype was detected, with marked ampicillin resistance. The majority was non-typeable. Very similar results were obtained even in URTI(+) (flu(-)) cases. CONCLUSION: Multiple drug-resistant S. pneumoniae with major serotypes, for example, 19 and 23 and H. influenzae with serotype b were already present at the initial stage of influenza infection, similar to URTI(+) flu(-) cases. They could be prevented by current vaccines, but drug-resistant non-typeable H. influenzae is troubling.

Molecular nature of methicillin-resistant Staphylococcus aureus derived from explosive nosocomial outbreaks of the 1980s in Japan.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) with Panton-Valentine leukocidin (PVL) genes is increasing worldwide. Nosocomial outbreak-derived (hospital-acquired) MRSA (HA-MRSA) in Japan in the 1980s was also largely PVL(+). PVL(+) HA-MRSA and CA-MRSA shared the same multi-locus sequence type (ST30) and methicillin resistance cassette (SCCmecIV), but were divergent in oxacillin resistance, spa typing, PFGE analysis or clfA gene analysis. PVL(+) HA-MRSA, which probably originated in PVL(+)S. aureus ST30, was highly adhesive (carrying cna and bbp genes), highly-toxic (carrying luk(PV) and sea genes) and highly drug-resistant. PVL(+) HA-MRSA was once replaced by other PVL(-) HA-MRSA (e.g., ST5), and is re-emerging as CA-MRSA.

[Anesthetic management with propofol, fentanyl TCI and BIS in two cases of secondary hyperthyroidism due to TSH secretion from pituitary adenomas].

We managed two patients with secondary hyperthyroidism due to TSH secretion from pituitary adenomas using total intravenous anesthesia with propofol and fentanyl. Both propofol and fentanyl were infused with target-controlled infusion (TCI) systems. The anesthesiologists controlled the target concentration of propofol to maintain the bispectral index (BIS) in a range from 40 to 60, and the target concentration of fentanyl was kept within a range of 2.0 to 3.0 ng.ml-1. Propranolol was injected in 0.4 mg increments to a total dosage of 2.4 to 3.2 mg. Prostaglandin E1 (PGE1) was infused at a rate from 0.01 to 0.04 microgram.kg-1.min-1 to maintain a stable heart rate and stable systemic blood pressure. The anesthetic effects were excellent in both patients. The necessary concentration of propofol during anesthesia was 2.5 to 4.0 micrograms.ml-1, and the emergence concentration of propofol was 1.4 to 1.7 micrograms.ml-1. These values were almost equal to those obtained in patients without thyroid disease. In conclusion, we could maintain the anesthesia for the patients with hyperthyroidism safely and stably by titrating the concentration of propofol and fentanyl based on the BIS value, and by administrating propranolol and PGE1 to avoid hypertension and tachycardia.

Genotypes, intrafamilial transmission, and virulence potential of nasal methicillin-resistant Staphylococcus aureus from children in the community.

Pediatric outpatients and healthy children in the community were examined for nasal methicillin-resistant Staphylococcus aureus (MRSA) in Japan. MRSA isolation frequencies were 0.7% (3/426) and 3.7% (5/136), respectively, in pediatric outpatients and healthy children in the community (overall frequency, 1.4%). The frequency of MRSA isolation was higher in children 5-9 years of age compared with the other age groups. All eight MRSA strains isolated were Panton-Valentine leukocidin-negative. Of these, three with the genotype multilocus sequence type (ST) 8/spa606/SCCmecIV (2 cases) and ST88/spa999/SCCmecIV/exfoliative toxin A gene (eta) were identical or similar to MRSA from bullous impetigo, determined by pulsed-field gel electrophoresis. One strain with ST764 (ST5 variant)/spa2/SCCmecII/staphylococcal enterotoxin B gene seb2 (seb variant) was similar to MRSA from bacteremia, and one with ST5/spa2/SCCmecII was the Pandemic New York/Japan clone. The remaining three strains, with ST22/spa998/SCCmecI, ST380/spa799/SCCmecIV, and ST857/spa416/SCCmecII, have not been identified. All MRSA strains were resistant to one or more non-beta-lactam antibiotics, and the ST5 and ST764 strains were multidrug-resistant. Family analysis demonstrated parent-to-child transmission (for ST8 and ST764), as well as acquisition from outside the family (for ST8 and ST380). The data suggest that young school-age children have a higher carriage rate of nasal MRSA than children of other ages, and that not only community-acquired MRSA strains but also MRSA strains with characteristics of hospital-acquired MRSA are spreading in the community.

A rapid screening method for Panton-Valentine leucocidin-positive community-acquired methicillin-resistant Staphylococcus aureus belonging to multilocus sequence type 30 and its related clone using a combination of multiplex PCR and pulsed-field gel electrophoresis.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA), which is often positive for Panton-Valentine leucocidin (PVL), is increasingly noted as an emerging pathogen worldwide. In Japan, PVL-positive CA-MRSA belonging to multilocus sequence type (ST) 30 has spread and caused, for example, pediatric death due to community-acquired pneumonia and severe pelvic abscesses in an athlete. In this study, we investigated a new rapid screening method for PVL-positive ST30 CA-MRSA and its related clone by a combination of multiplex polymerase chain reaction (M-PCR) and pulsed-field gel electrophoresis (PFGE). For M-PCR, the targets of the assay were the five genes for PVL, collagen adhesin, bone sialoprotein adhesin, methicillin resistance, and S. aureus-specific thermostable nuclease. Only PVL-positive ST30 CA-MRSA strains produced all five bands in M-PCR. With PFGE, Japanese strains and most foreign strains of PVL-positive ST30 CA-MRSA shared the same pattern. Moreover, PFGE distinguished current PVL-positive CA-MRSA ST30/spa19 strains from previous PVL-positive MRSA ST30/spa43 strains (which were isolated at the time of nosocomial MRSA outbreaks in the late 1980s and early 1990s) in Japan. Thus, the M-PCR assay rapidly, and the M-PCR/PFGE combination assay more precisely, discriminated between PVL-positive ST30 CA-MRSA (or its related clone) and PVL-positive CA-MRSA belonging to other ST types such as ST1, 8, 59, and 80, PVL-negative CA-MRSA, hospital-acquired MRSA, methicillin-susceptible S. aureus, or coagulase-negative staphylococci (CNS), including MRCNS. This screening method is more useful than genotyping for routine work in many clinical laboratories.

An outbreak and isolation of drug-resistant Pseudomonas aeruginosa at Niigata University Hospital, Japan.

Pseudomonas aeruginosa is an opportunistic pathogen that causes disease in patients with impaired host defenses; it is often a cause of life-threatening nosocomial infection in critically ill and immunocompromised patients. An increase in the prevalence of multiple-drug-resistant Pseudomonas aeruginosa (MDRP) in hospitals is thus a worldwide problem. These increases are frequently related to the high selective pressure of antimicrobials commonly used in hospitalized patients, particularly extended-spectrum cephalosporins, beta-lactamase-inhibitor combinations, carbapenems, fluoroquinolones, and aminoglycosides. We evaluated the clinical and microbiological characteristics of drug-resistant P. aeruginosa and MDRP strains that were isolated at Niigata University Hospital, Japan, from 2000 to 2004. We experienced an outbreak of MDRP in 2000, but colonization only was the main feature of the outbreak. Also, the isolation rate of MDRP has decreased since 2004; this reduction in the isolation rate seems to be a result of a move to newly built ward sections in 2001 and the establishment of an infection control team (ICT) in 2003.

Novel characteristics of community-acquired methicillin-resistant Staphylococcus aureus strains belonging to multilocus sequence type 59 in Taiwan.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) strains, which often produce Panton-Valentine leucocidin (PVL), are increasingly noted worldwide. In this study, we examined 42 MRSA strains (25 PVL-positive [PVL+] strains and 17 PVL-negative [PVL(-)] strains) isolated in Taiwan for their molecular characteristics. The PVL+ MRSA strains included CA-MRSA strains with multilocus sequence type (ST) 59 (major PVL+ MRSA in Taiwan), its variants, and worldwide CA-MRSA ST30 strains. The PVL(-) MRSA strains included the pandemic Hungarian MRSA ST239 strain, the Hungarian MRSA ST239 variant, MRSA ST59 (largely hospital-acquired MRSA strains) and its variants, the pandemic New York/Japan MRSA ST5 strain (Japanese type), and the MRSA ST8 strain. The major PVL+ CA-MRSA ST59 strain possessed a tetracycline resistance-conferring (tetK positive) penicillinase plasmid and a drug resistance gene cluster (a possible composite transposon) for multidrug resistance. Moreover, it carried a novel staphylococcal cassette chromosome mec (SCCmec) with two distinct ccrC genes (ccrC2-C8). This SCCmec (previously named SCCmec type V(T)) was tentatively designated SCCmec type VII. Sequencing of the PVL genes revealed the polymorphisms, and the PVL+ CA-MRSA ST59 strain possessed the ST59-specific PVL gene sequence. The data suggest that a significant amount of clonal spread is occurring in Taiwan and that the major PVL+ CA-MRSA ST59 Taiwan strain exhibits unique genetic characteristics, such as a novel SCCmec type and an ST59-specific PVL gene sequence.

Molecular characterization of methicillin-resistant Staphylococcus aureus in hospitals in Niigata, Japan: divergence and transmission.

The major methicillin-resistant Staphylococcus aureus(MRSA) distributed among hospitals in Japan is New York/Japan clone [multilocus sequence type 5 (ST5), agr type 2 and methicillin resistance locus type (SCC mec) II] which possesses both the toxic shock syndrome toxin 1 gene (tst) and staphylococcal enterotoxin C gene (sec). In this study, we collected 245 MRSA strains from four hospitals during 2001 to 2005 in Niigata, Japan, and analyzed tst and sec genes and SCC mec type among them. A total of 13 strains were further examined for their genotypes, virulence gene patterns and drug resistance. Among the 245 strains four tst sec genes patterns were observed; tst(+) sec(+) strains represented a majority of 86.5% and 9.4% were tst(-) sec(-). SCCmec typing revealed that 91.4% had type II, 4.1% type IV and 4.1% type I. Multilocus sequence typing (MLST) revealed that 10 of the 13 typed strains belonged to clonal complex 5 (7 had ST5 while 3 were single locus variants of ST5) with similar characteristics to the New York/Japan clone and possessed multi-drug resistance with high virulence gene content. The remaining 3 strains were ST8 (n=2) and ST91 (n=1). The ST91 strain had SCC mec IV and seemed to originate in the community, while ST8 strains exhibited SCC mec type I, which is distinct from community type IV. The data suggest that MRSA in hospitals in Niigata now mainly includes the New York/Japan clone (undergoing genomic divergence and clonal expansion) and other minor types (e.g. ST8) as well as the community type.

Anesthetic management of a pediatric patient on a ketogenic diet.

There are several specific considerations regarding seizure control during the perioperative period in patients who have been placed on a ketogenic diet (KD). A KD is high in fat and low in protein and carbohydrates and has a long history of use for the treatment of intractable seizures in children. Maintaining therapeutic ketosis and modifying the acid-base balance are particularly important for preventing seizures in patients on a KD. We report changes in the biochemical parameters of a patient with double cortex syndrome who was on a KD and who had been scheduled for the treatment of dental caries under sevoflurane anesthesia and acetate Ringer administration. Inhalation induction with a high concentration of sevoflurane should be reconsidered in view of recent reports describing the epileptogenic potential of sevoflurane.

A Panton-Valentine leucocidin (PVL)-positive community-acquired methicillin-resistant Staphylococcus aureus (MRSA) strain, another such strain carrying a multiple-drug resistance plasmid, and other more-typical PVL-negative MRSA strains found in Japan.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) was collected from children with bullous impetigo in 2003 and 2004. One strain collected in 2003 was Panton-Valentine leucocidin (PVL) positive. In 2004, a multiple-drug-resistant PVL(+) CA-MRSA strain was isolated from an athlete with a cutaneous abscess. These strains were analyzed by multilocus sequence typing, spa typing, agr typing, coagulase typing, staphylococcal cassette chromosome mec (SCCmec) typing, PCR assay for 30 virulence genes, drug susceptibility testing, pulsed-field gel electrophoresis, and for plasmids. The two Japanese PVL(+) CA-MRSA strains belonged to the globally extant ("pandemic") sequence type 30 (ST30) with SCCmec IV. A transmissible, multiple-drug resistance plasmid emerged in such ST30 strains. The PVL(-) CA-MRSA strains ("domestic" CA-MRSA) accumulated for bullous impetigo, exhibiting new genotypes. Hospital-acquired MRSA of ST91 (but not pandemic ST5) shared common features with the PVL(-) CA-MRSA strain.