Infection control for a methicillin-resistant Staphylococcus aureus outbreak in an advanced emergency medical service center, as monitored by molecular analysis.

A methicillin-resistant Staphylococcus aureus (MRSA) outbreak occurred in an advanced emergency medical service center between 2010 and 2011. Our objective was to evaluate the status of the MRSA outbreak, as monitored by molecular analysis. Twenty-eight MRSA strains were isolated from blood samples from 11 patients, from other specimens (pharynx, nasal cavity, etc.) from 12 patients, from two environmental samples, and from the skin, middle nasal meatus, and urine of one patient each from other wards. Pulsed-field gel electrophoresis (PFGE) was performed to evaluate horizontal transmission. Molecular typing by PFGE showed that the 28 MRSA strains presented 7 patterns in total, and that 11 of the MRSA strains had the same PGFE pattern. Unselective use of intranasal mupirocin ointment, MRSA monitoring for new inpatients, and prevention of direct or indirect contact infection were performed. However, the number of inpatients with MRSA did not quickly decrease, and additional molecular typing by PFGE showed that 10 of 19 MRSA strains found (5 of 6 from blood, 5 of 13 from other specimens) were the same as those found previously. Lectures and ward rounds were performed repeatedly, and staff participation in ward rounds was suggested. Finally, the number of inpatients with MRSA significantly decreased more than 6 months after the intervention. Although the MRSA outbreak was thought to have ended, follow-up molecular typing by PFGE showed that horizontal transmission persisted. Our data suggest that various combinations of infection control measures are essential when dealing with an MRSA outbreak, and monitoring by molecular analysis using PFGE is useful to identify the status of the outbreak.

Safety and immunogenicity of a 15-valent pneumococcal conjugate vaccine in Japanese healthy infants: A Phase I study (V114-028).

This Phase I study evaluated the safety, tolerability, and immunogenicity of V114, a 15-valent pneumococcal conjugate vaccine (PCV), via subcutaneous (SC) or intramuscular (IM) administration, in healthy Japanese infants 3 months of age. A total of 133 participants were randomized to receive four doses (3 + 1 regimen) of V114-SC (n = 44), V114-IM (n = 45), or 13-valent PCV (PCV13)-SC (n = 44) at 3, 4, 5, and 12-15 months of age. Diphtheria, tetanus, and pertussis-inactivated poliovirus (DTaP-IPV) vaccine was administered concomitantly at all vaccination visits. The primary objective was to assess the safety and tolerability of V114-SC and V114-IM. Secondary objectives were to assess the immunogenicity of PCV and DTaP-IPV at 1-month post-dose 3 (PD3). On days 1-14 following each vaccination, the proportions of participants with systemic adverse events (AEs) were comparable across interventions, whereas injection-site AEs were higher with V114-SC (100.0%) and PCV13-SC (100.0%) than with V114-IM (88.9%). Most AEs were mild or moderate in severity and no vaccine-related serious AEs or deaths were reported. Serotype-specific immunoglobulin G (IgG) response rates at 1-month PD3 were comparable across groups for most shared serotypes between V114 and PCV13. For additional V114 serotypes 22F and 33F, IgG response rates were higher with V114-SC and V114-IM than with PCV13-SC. DTaP-IPV antibody response rates at 1-month PD3 for V114-SC and V114-IM were comparable with PCV13-SC. Findings suggest that vaccination with V114-SC or V114-IM in healthy Japanese infants is generally well tolerated and immunogenic.

[Antibiotic therapy against acute tonsillopharyngitis in children due to group A beta-hemolytic streptococci: comparison of clinical efficacy, the bactericidal effects, and effects on oral flora between cefditoren pivoxil for 5 days and amoxicillin for 10 days].

We compared the clinical efficacy, the bactericidal effects, effect on the oral microbial flora, and adverse reactions between cefditoren pivoxil (CDTR-PI) for 5 days and amoxicillin (AMPC) for 10 days in children with acute group A beta-hemolytic streptococci (GAS) tonsillopharyngitis, and simultaneously examined the emm genotype and drug susceptibility of the isolated GAS. The results showed that the clinical efficacy was 100% for CDTR-PI and 97.9% for AMPC, with no difference between the two groups, and the bacterial elimination rate was 100% in both groups. No serious adverse event was noted in either group. On the other hand, concerning changes in the oral microbial flora between before and after treatment, the amount of bacteria showed no change in the CDTR-PI group (p = 0.5761) but clearly decreased in the AMPC group (p = 0.0049). This indicates that CDTR-PI does not disturb the oral microbial flora compared with AMPC. Also, the emm types determined in the 112 GAS strains isolated in this study were similar to those that have recently been isolated frequently in Japan. Concerning the drug resistance, none of the isolates showed resistance to beta-lactam antibiotics, but 45% of them were resistant to macrolides. The advantages of short-term treatment are considered to include a lower cost, improvement in drug compliance, decrease in the frequency of the occurrence of adverse reactions, decrease in the frequency of the appearance of drug-resistant strains, and alleviation of the psychological burden of patients and their parents. For these reasons, we conclude that CDTR-PI for 5 days is a useful option for the treatment of acute GAS tonsillopharyngitis in children.

Genotypes of macrolide-resistant pneumococci from children in southwestern Japan: raised incidence of strains that have both erm(B) and mef(A) with serotype 6B clones.

MICs of penicillin G, erythromycin, clarithromycin, clindamycin, azithromycin, and telithromycin were tested for 189 clinical isolates collected during 2002 to 2005 from children in southwestern Japan. Serotyping and polymerase chain reaction for presence of erm(B) and mef(A) were performed. All strains with erm(B) + mef(A) were analyzed by pulsed-field gel electrophoresis (PFGE) and compared to 3 global clones: Spain(23F)-1; Spain(9V)-3 and its variant -14; a South Korean strain same as Taiwan (19F)-14 clone and 5 strains with erm(B) + mef(A) from other countries. Of the 173 macrolide-resistant (erythromycin MIC > or =0.5 microg/mL) strains, 104 (60.1%) had erm(B), 47 (27.2%) had mef(A), and 22 (12.7%) had erm(B) + mef(A). Strains expressing erm(B) or both erm(B) and mef(A) had high macrolide MIC(90)s (>64 microg/mL), except telithromycin (MIC(90), 0.25 microg/mL). Of the 22 erm(B) + mef(A) strains, 10 had 4 distinct PFGE patterns and were mainly serotype 6B clones, which differed from those described in previous reports; 5 other strains had unique profiles.

[A case of bacterial meningitis due to Streptococcus bovis in an infant with normal cerebrospinal fluid findings at the first CSF examination].

Streptococcus bovis very occasionally causes rarely sepsis, endocarditis, and meningitis in newborns and the elderly. We report the case of infant meningitis caused by S. bovis despite normal cerebrospinal fluid (CSF) findings at the first CSF examination. A 77-day-old boy with 21-trisomy and patent foramen ovale and seen for a high fever underwent blood examination and lumbar puncture due to toxic appearance despite a lack of meningeal signs, and was admitted. His CSF findings were normal and he was given intravenous ceftriaxone against potential bacteremia. He had systemic seizures with continuous fever for 2 days after admission and a second CSF examination. Gram-positive coccus grew from his CSF at the first examination, and CSF cells from the second lumbar puncture increased to 4060/tL (86% neutrophils), so vancomycin was added against potential enterococcal meningitis. S. bovis was finally grown from the first CSF, ceftriaxone discontinued, and intravenous ampicillin added. He recovered after 20 days of antibiotic administration. S. bovis becomes a potential pathogen for meningitis in infants, and must be considered as a cause of meningitis despite its very rarity. CSF findings at the first lumbar puncture may be normal for meningitis in newborns and infants at the first CSF examination, so we must be very careful in the diagnosis of bacterial meningitis even with normal CSF findings, and considered antibiotic treatment against potential bacterial meningitis.

[Dipylidium caninum infection in an infant].

Dipylidium caninum, the dog tapeworm, is a common intestinal cestode of domestic dogs and cats, but few cases have been reported of human infection by this parasite in Japan. We repot a case of D. caninum infection in a 17 month-old girl, who sometimes had symptoms of abdominal pain, diarrhea, and dysphoria at night. Her mother noted the appearance of small white worms in her stool, and she was seen by a local pediatrician. Despite antiparasitic therapy wiht pyrantel pamoate, the problem persisted and was eventually referred for further workup to Kurume University Hospital. The diagnosis was made by microscopic examination of the excreted proglottids, which contained characteristic egg capsules. She was successfully treated with a singledose of praziquantel and four adult parasites were recovered. The longest intact worm was 32cm. Her family had household pets (a dog and a cat). The pets were seen by the local veterinary and both were evidenced D. caninum. Humans, primarily children, become infected when they accidentally ingest fleas. Parents usually find proglottids as multiple white objects, often described as cucumber, melon, or pumpkin seeds, in stool, diapers, or on the perineum. Most general practitioners and pediatricians may treat children with enterobiasis (pinworm) infection, and in case the treatment fails, other parasite infection should be considered such as this worm. A history of dog or cat pets, fleas, and flea bites may be important clues to diagnosis. Pets found to be infected should also be treated.

Potential drug interaction between warfarin and linezolid.

OBJECTIVE: Warfarin is known to interact with many drugs; however, there are currently no descriptions of an interaction with linezolid in the literature. It was recently brought to our attention, however, that several warfarin-medicated patients have experienced an increase in the prothrombin time international normalized ratio (PT-INR) following the administration of linezolid. We therefore performed a retrospective survey in order to investigate the possibility of an interaction between warfarin and linezolid. METHODS: The survey items included age, gender, underlying disease, type of surgery, type of infectious disease, duration of linezolid administration, laboratory values and the dose of warfarin. The PT-INR was observed over time before treatment and at days 4 or 5 and 10, completion and one week after the end of concomitant therapy. Patients The subjects included six patients who were recovering from recent heart-related surgery. RESULTS: The PT-INR increased from 1.62±0.32 before concomitant linezolid administration to 3.00±0.83 at day 4 or 5 after concomitant administration (p<0.01) and significantly decreased from 1.65±0.45 at the completion of the regimen to 1.26±0.1 one week later (p<0.05). With respect to the relationship between the dose of warfarin and the PT-INR in five cases, the PT-INR increased following concomitant linezolid treatment in all cases. CONCLUSION: Although it has been reported that linezolid does not influence the metabolism or protein binding of warfarin, our data showed potential drug interactions between warfarin and linezolid. Our data suggest that PT-INR monitoring after the completion of concomitant warfarin and linezolid therapy is important.