To determine the impact of an inpatient stewardship intervention targeting fluoroquinolone use on inpatient and postdischarge Clostridioides difficile infection (CDI).

We used an interrupted time series study design to evaluate the rate of hospital-onset CDI (HO-CDI), postdischarge CDI (PD-CDI) within 12 weeks, and inpatient fluoroquinolone use from 2 years prior to 1 year after a stewardship intervention.

An academic healthcare system with 4 hospitals.

All inpatients hospitalized between January 2017 and September 2020, excluding those discharged from locations caring for oncology, bone marrow transplant, or solid-organ transplant patients.

Introduction of electronic order sets designed to reduce inpatient fluoroquinolone prescribing.

Among 163,117 admissions, there were 683 cases of HO-CDI and 1,104 cases of PD-CDI. In the context of a 2% month-to-month decline starting in the preintervention period (P < .01), we observed a reduction in fluoroquinolone days of therapy per 1,000 patient days of 21% after the intervention (level change, P < .05). HO-CDI rates were stable throughout the study period. In contrast, we also detected a change in the trend of PD-CDI rates from a stable monthly rate in the preintervention period to a monthly decrease of 2.5% in the postintervention period (P < .01).

Our systemwide intervention reduced inpatient fluoroquinolone use immediately, but not HO-CDI. However, a downward trend in PD-CDI occurred. Relying on outcome measures limited to the inpatient setting may not reflect the full impact of inpatient stewardship efforts.

To evaluate intrahospital and interhospital clonal dissemination of extended-spectrum beta-lactamase (ESBL)-producing strains of Klebsiella pneumoniae.

Eight tertiary-care university hospitals and 16 regional hospitals in Taiwan.

Two hundred eleven confirmed ESBL-producing isolates of K. pneumoniae were collected from January 1998 to June 2000. The isolates were characterized by various typing methods, including antibiogram (9 antimicrobial agents), computer-based ribotyping, pulsed-field gel electrophoresis (PFGE), and isoelectric focusing of beta-lactamase.

Ribotyping identified 70 distinct ribogroups among 200 isolates evaluated. Forty-three of these ribogroups were unique. Eleven ribogroups, comprising 115 isolates, were detected in more than one hospital (interhospital dissemination), whereas 16 groups (42 isolates) were detected in more than one patient within a hospital (intrahospital dissemination). The combination of ribotyping and PFGE identified two large epidemic clones, which were called 691.5/PFGE-G and 595.7/PFGE-A. These epidemic clones were detected mainly in the hospitals located in the northern and central regions of Taiwan. However, variation of the profiles of antibiograms and isoelectric focusing was apparent within each clone. In addition, isolates with the same isoelectric focusing profile (isoelectric points 7.9, 8.2, and 8.4) and antibiogram (resistance to 9 compounds evaluated) were present among different molecular-typed clones.

Our results showed that clonal dissemination (both interhospital and intrahospital dissemination) is occurring in several regions of Taiwan. Rapid computer-based ribotyping associated with PFGE demonstrated multiple epidemic clones of ESBL-producing K. pneumoniae in Taiwan. The combination of phenotypic and molecular methods has proved useful to characterize these epidemic clones.

To characterize vancomycin-resistant enterococci (VRE) isolates and to evaluate the mode of dissemination of this pathogen in Brazil.

We collected 22 vancomycin-resistant Enterococcus faecium isolates from 6 medical centers in Sao Paulo, Brazil, and 1 isolate from a medical center in Curitiba, Brazil.

All Brazilian hospitals that had identified vancomycin-resistant E. faecium up to the beginning of this study (late 1999) contributed isolates to the study.

The isolates were susceptibility tested using the broth microdilution method and the E-test. The presence of vancomycin resistance genes (vanA, vanB, vanC1, vanC2-3, and vanD) was evaluated by polymerase chain reaction; molecular typing was performed by pulsed-field gel electrophoresis (PFGE).

The vanA gene was demonstrated in all vancomycin-resistant E. faecium, except for 1 isolate. None of the vancomycin resistance genes cited above was detected in the isolate from Curitiba, which was the first vancomycin-resistant E. faecium described in Brazil. All isolates were resistant to ampicillin and teicoplanin. The main clone remains susceptible to doxycycline and chloramphenicol, but intermediate to quinupristin-dalfopristin. PFGE analysis demonstrated 7 major PFGE patterns. A unique PFGE pattern with 4 subtypes was detected in 17 isolates from 4 different hospitals.

The results of our study indicate the occurrence of intra- and interhospital dissemination of VRE in Sao Paulo, Brazil.

To investigate a cluster of Serratia odorifera in a cardiothoracic surgery unit (CTSU) and to evaluate the applicability of three typing methods for this species.

During a surveillance surgical wound study, S odorifera was isolated from two patients in the CTSU. The patients' hospital charts were reviewed for the details of surgery and for common personnel, procedures, or medications. Cultures were obtained of water, soap, and unit dose medications from the CTSU, the operating room, and the surgical intensive care unit. The isolates' antibiograms, biotypes (Vitek identification card and API 20E), and patterns of chromosomal DNA (chrDNA) by pulsed-field gel electrophoresis (PFGE) were examined. S odorifera isolates from our organism collection were used as controls.

A 900-bed university hospital with a 22-bed CISU.

ChrDNA patterns of isolates from the two patients were identical, suggesting a possible nosocomial source. However, no source of organisms or mode of transmission was identified. Neither biotype nor antibiogram were useful for epidemiologically typing S odorifera, and PFGE was necessary to discriminate among isolates.

Although rarely isolated, S odorifera and other non- marcescens Serratia species may cause nosocomial outbreaks. PFGE of chrDNA seems to be a reliable method for epidemiologically typing this species.

To investigate the possibility of interhospital spread of multiresistant Staphylococcus aureus in Sao Paulo, Brazil.

We evaluated 13 nosocomial S aureus strains selected because of resistance to oxacillin and ciprofloxacin.

The strains were collected between March 1991 and September 1991 from four hospitals in Sao Paulo. Two were teaching hospitals, and two were private hospitals.

Each strain was isolated from a different patient. All patients were hospitalized when the strains were isolated.

The strains were typed by restriction endonuclease analyses of plasmid DNA (REAP) using EcoRI, HindIII, RsaI, and Alu1 and by extended antibiogram profile (34 drugs).

All strains had identical plasmid and antibiogram profile. They demonstrated the same plasmid pattern as previously described in one of the hospitals studied.

Our results suggest the dissemination of a unique oxacillin- and quinolone-resistant strain of S aureus in several hospitals of Sao Paulo, Brazil.