Using a stacker crane for sterile storage in the operating theatre: initial environmental microbiological qualification.

BACKGROUND: Adequate storage of sterile surgical devices must prevent contamination and the introduction of microbial contaminants inside the operating room. For functional and economic purposes, stacker cranes (STCs) could replace the traditional sterile storage room (TSSR). STCs are large, multi-stage, computer-assisted systems used to automatically store and retrieve loads from defined locations. However, their microbiological performance has not been evaluated. AIM: As part of the opening of a new building that included an operating theatre, we qualified a new STC and compared its microbiological control performance to that of the previous TSSR. METHODS: From December 2020 to March 2021, 590 environmental specimens (air, N = 56; surfaces, N = 534) were collected and interpreted according to the NF S90-351 French Association for Standardization standards. FINDINGS: Thorough surface disinfection was not sufficient for controlling microbial contamination in the STC. Thus, the initial qualification testing was conducted following an aggressive aerial chemical decontamination of the STC. Despite the lack of a HEPA filtered air system, the overall non-conformity rates were lower in the STC than in the TSSR (8.3% vs 21.4%, P=0.33 for air, respectively, and 9.7% vs 41.7% P<0.001 for surfaces). The air-controlled barrier in front of the loading zone appeared to be sufficient to prevent bacterial contamination. The presence of fungi must be carefully monitored. CONCLUSION: This is the first study supporting the contribution of STCs in saving space and improving the maintenance of sterile surgical device storage and availability under acceptable environmental conditions. Further studies are needed to assess the long-term microbiological contamination inside the STC.

Local outbreak of extended-spectrum ß-lactamase SHV2a-producing Pseudomonas aeruginosa reveals the emergence of a new specific sub-lineage of the international ST235 high-risk clone.

BACKGROUND: Pseudomonas aeruginosa is a major bacterial pathogen responsible for hospital-acquired infections. Although its epidemiology is considered as non-clonal, certain international high-risk multidrug-resistant clones have been recognized. AIM: From the first report of an intra-hospital outbreak due to an SHV2a-producing P. aeruginosa strain, to describe the emergence of a new ST235-specific lineage harbouring this rare extended-spectrum ß-lactamase (ESBL). METHODS: Between May and October 2018, four patients hospitalized in the cardiovascular intensive care unit of a French teaching hospital were infected by a multidrug-resistant P. aeruginosa isolate. Serotype and antimicrobial susceptibility were tested; multi-locus sequence type (MLST), core genome MLST, and resistome were determined through whole genome sequencing. A phylogenetic analysis based on single nucleotide polymorphism was performed using available ST235 genomes. FINDINGS: The four strains were susceptible to colistin, ciprofloxacin, ceftazidime-avibactam, and ceftolozane-tazobactam. blaSHV2a was identified in each genome of this ST235-O11 serotype cluster that showed an identical cgMLST profile (0-2 out of 4162 different alleles). The phylogenic analysis of 162 ST235 genomes showed that only four other strains harboured a blaSHV2a, originating from France and USA, clustering together although being different from the outbreak strains. CONCLUSIONS: Among the ST235 P. aeruginosa strains, a sub-lineage sharing a common genetic background and harbouring the blaSHV2a ESBL seems to emerge from different locations, yielding secondary local outbreaks.

Contribution and limits of clinical specimens for the screening of intestinal multi-drug-resistant bacteria in view of laboratory automation.

The detection of multi-drug-resistant bacteria carriers constitutes a race against time for infection preventionists. Alongside standard analysis for diagnostic purposes and a rectal screening strategy, the authors tested a heavy-loaded selective method against 562 clinical specimens from 439 patients to detect extended-spectrum beta-lactamase-producing (ESBL) or carbapenemase-producing Enterobacteriaceae (CPE) and vancomycin-resistant enterococci (VRE). The approach identified five more specimens positive for ESBL-producing Enterobacteriaceae than standard analysis, and six out of nine known VRE/CPE carriers (three new CPE/VRE strains were also identified in this cohort). In view of the ongoing automation of laboratories, this approach focusing on urine and stool specimens may be an alternative or complementary approach to dedicated rectal screening.

Misuse of gloves: the foundation for poor compliance with hand hygiene and potential for microbial transmission?

Improvement in hand hygiene compliance is important for reducing cross-infection by micro-organisms. The objective of this prospective observational study was to measure how the improper use of gloves limits compliance to hand hygiene and exposes patient's to infection. The study was conducted in five wards (three intensive care units and two medical wards) in a French university hospital. Staff-patient and staff-environment contacts were observed in 120 healthcare workers caring for patients colonized or infected with pathogenic bacteria. Hand hygiene was not undertaken due to improper gloving in 64.4% (95%CI, 64.1% to 65.1%) of instances. Possible microbial transmission might have occurred in 18.3% (95%CI, 17.8% to 18.8%) of all contacts because used gloves were not removed before performing care activities that necessitated strict aseptic precautions. Failure to change or remove contaminated gloves was a major component in the poor compliance with hand hygiene and carried a high-risk of microbial transmission. Improving hand hygiene compliance will require changing healthcare workers behaviour towards glove use.

Comparison of systematic versus selective screening for methicillin-resistant Staphylococcus aureus carriage in a high-risk dermatology ward.

OBJECTIVE: To compare two strategies for screening methicillin-resistant Staphylococcus aureus (MRSA) carriers in a high-risk dermatology ward: systematic screening of all admitted patients versus selective screening of patients at risk. DESIGN: The two strategies were applied prospectively during two consecutive periods. In period A (8.5 months), only patients transferred from other wards, or with a history of prior hospitalization, or presenting chronic wounds or disease with denuded skin were considered at high risk of MRSA carriage and sampled. In period B (7.5 months), all admitted patients were systematically screened. End-points were the number of patients having a MRSA-positive screening sample on admission during period B and having none of the risk factors used in period A, the rate of imported MRSA cases, and the rate of acquired cases. SETTING: A 1,032-bed university hospital with a 19-bed inpatient dermatology ward, a referral center for toxic epidermal necrolysis and severe extensive dermatoses. PATIENTS: The study included 729 dermatology inpatients (370 in period A and 359 in period B). RESULTS: During period A, screening samples were obtained on admission for 30% of patients (77% of the patients at risk) and identified 25 MRSA carriers. During period B, 90.5% of admitted patients were screened, and 26 MRSA carriers were detected on admission; all of these patients belonged to at least one predefined category at risk for carriage. Overall rates of imported and acquired cases were similar between the two periods (6.8% vs 7.5%, and 2.9% vs 2.4%, respectively). CONCLUSIONS: A screening strategy targeted to patients at risk of harboring MRSA has similar sensitivity and is more cost-effective than a strategy of systematic screening to identify MRSA carriers on admission.

Selective screening of carriers for control of methicillin-resistant Staphylococcus aureus (MRSA) in high-risk hospital areas with a high level of endemic MRSA.

Screening for methicillin-resistant Staphylococcus aureus (MRSA) carriage in patients at risk was evaluated as part of a control program in a 26-bed medical intensive care unit (ICU) of a university hospital with a high level of endemic MRSA. Control measures included isolation and barrier precautions, skin decolonization with chlorhexidine of patients from whom MRSA was recovered, and mupirocin treatment of nasal carriers of MRSA. Of 3,686 patients admitted during a 4-year period, 44% were screened, which occurred during admission for 38%; MRSA was recovered from 293 patients (8%). There were 150 imported cases and 143 ICU-acquired cases, of which 51% and 45%, respectively, were first identified through screening. Nasal swab cultures identified 84% of MRSA carriers. The incidence of all ICU-acquired cases and of acquired colonization or infection decreased from 5.8% and 5.6% to 2.6% and 1.4% (P = .002 and P < .001), respectively, whereas that of imported cases remained unchanged (range, 3.8% to 4.3%; P = .8). Selective screening for nasal carriage during admission to high-risk areas may contribute to identification of a substantial proportion of cases of MRSA and to early implementation of effective control measures.