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This study was intended to investigate the trend in vancomycin susceptibility and correlation with molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) causing invasive infections. A total of 670 MRSA isolates were collected from patients with invasive infections as part of bacterial collection in the Tigecycline in vitro Surveillance in Taiwan (TIST) from 2006 to 2010. MICs of the isolates to vancomycin were determined using the agar dilution method. Characteristics of staphylococcal cassette chromosome mec (SCCmec), mec-associated hypervariable region (dru), and accessory gene regulator (agr) of the isolates were identified by polymerase chain reaction methods. MRSA isolates with SCCmec types I, II, and III were molecularly defined as hospital-associated MRSA (HA-MRSA), and those with SCCmec types IV, V, and VT were assigned as community-associated MRSA (CA-MRSA). All but 1 MRSA isolates exhibited vancomycin MICs ≤1 mg/L. A declining trend in vancomycin MICs among MRSA isolates was noted, which was associated with the decline in proportion of HA-MRSA. The percentage of CA-MRSA increased from 25.6% in 2006 to 46.0% in 2010. An increase in the geometric mean of vancomycin MICs was found in MRSA with particular molecular types such as SCCmec types II and III, agr groups I and II, and dru10-14. A significant correlation among particular molecular types was found, including SCCmecII-agr group II-dru4, SCCmecIII-agr group I-dru11-14, SCCmecIV-agr group II-dru9, and SCCmecVT-agr group I-dru9 and dru11. There was no vancomycin creep among MRSA isolates, and the declining trend of vancomycin MIC against MRSA was attributed to the increasing prevalence of CA-MRSA over time.

Summary Background Serratia marcescens is an important nosocomial pathogen causing significant outbreaks. Here we report an outbreak of bloodstream infection caused by S. marcescens at a 3500-bed hospital in Taiwan. The effective cooperative efforts of both laboratory personnel and infection control practitioners (ICPs) jointly contributed to the total control of the outbreak. Methods A sudden increase in the isolation of S. marcescens from blood cultures was noted in the Clinical Microbiology Laboratory. The information was passed to the ICPs and an investigation was initiated. Pulsed-field gel electrophoresis was used to study the relationships among the isolates. Results Pulsotype A was identified in 43 (82.7%) of the 52 blood isolates studied. They were isolated from 52 patients distributed across 22 wards that were surveyed by seven ICPs. All patients had undergone surgery before the infection, and fentanyl-containing intravenous fluids were used for pain control in 43 of them. Isolates from 42 belonged to pulsotype A. Three S. marcescens isolates, all from fentanyl-containing fluids and demonstrating pulsotype A, were identified from 251 environmental cultures. All fentanyl-containing fluids that were in use were withdrawn and the outbreak was stopped. Conclusions The outbreak of S. marcescens bloodstream infection apparently occurred through the use of fentanyl-containing fluids contaminated by a pulsotype A S. marcescens .

A total of 393 isolates of A. baumannii were collected from patients treated at 19 teaching hospitals in Taiwan. Minimum inhibitory concentrations (MICs) and inhibitory zone diameters for tigecycline were determined by the broth microdilution method and the disk diffusion method, respectively. The MIC results were interpreted using the US FDA tigecycline susceptibility breakpoints for Enterobacteriaceae (susceptible [S]or=2 microg/mL; intermediate [I] 4 microg/mL; resistant [R]or=8 microg/mL). The disk diffusion results were interpreted by criteria recommended by Jones et al. (Sor=16 mm; I 13-15 mm; Ror=12 mm) and also by those recommended by the US FDA for Enterobacteriaceae (Sor=19 mm; I 15-18 mm; Ror=14 mm). The percentages of susceptible, intermediate and resistant isolates determined by the broth microdilution method were 80.9%, 12.2%, and 6.9%, respectively. The rates of susceptible, intermediate and resistant isolates by the disk diffusion method using the criteria of Jones et al. were 88.3%, 9.9% and 1.8% and using the US FDA criteria were 44.0%, 51.7% and 4.3%. Using the criteria recommended by Jones et al., the total error rate of the disk diffusion method in comparison with the broth microdilution method was 14.2% (56/393). For routine susceptibility testing of tigecycline against A. baumannii the broth microdilution method, not the disk diffusion method, should be used due to the poor correlation of results between these two methods interpreted either by the Jones et al. or US FDA criteria.

Motor involvement in acute herpes zoster does occur,but is rare. Most causes of zoster paresis are due to the extension of the inflammation to the anterior horn and/or anterior motor roots. We report a female patient with an unusual diaphragmatic paralysis caused by cervical herpes zoster. The lesion, diagnosed by MRI, involved the anterior horn of the cervical spinal cord.