In search of the best method to detect carriage of carbapenem-resistant Pseudomonas aeruginosa in humans: a systematic review.

BACKGROUND: Detection of carbapenem-resistant Pseudomonas aeruginosa (CR-PA) in humans is important to prevent transmission. However, the most optimal culture method to detect CR-PA is unknown. This systematic review aims to determine which culture method is most sensitive and which culture methods are used to detect CR-PA in humans. Second, to establish the most feasible culture method taking into account the turnaround time (TAT), and third, to provide an overview of the sampling sites used to detect carriage. METHODS: We systematically searched the electronic databases Embase, Medline Ovid, Cochrane, Scopus, CINAHL, and Web of Science until January 27, 2023. All diagnostic accuracy studies comparing two or more culture methods to detect CR-PA and recent outbreak or surveillance reports on CR-PA carriage or infection in humans, which describe culture methods and their results, were eligible for inclusion. We used QUADAS-2 guideline for diagnostic accuracy studies and the STROBE or ORION guideline for outbreak-surveillance studies to assess the risk of bias. RESULTS: Six diagnostic accuracy studies were included. An enrichment broth was found to increase the detection of CR-PA. Using an enrichment broth extended the TAT by 18-24 h, yet selective media could reduce the TAT by 24 h compared to routine media. In total, 124 outbreak-surveillance studies were included, of which 17 studies with surveillance samples and 116 studies with clinical samples. In outbreak-surveillance studies with surveillance samples, perianal, rectal swabs or stools were the most common sampling site/specimen (13/17, 76%). A large variety was observed in whether and which kind of enrichment broth and selective media were used. CONCLUSIONS: We found a benefit of using an enrichment step prior to inoculation of the material onto selective media for the detection of CR-PA. More research is needed to determine the most sensitive sampling site and culture method. TRAIL REGISTRATION: This study was registered in the PROSPERO International prospective register of systematic reviews (registration number: CRD42020207390, http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42020207390 ).

Detection of carbapenemase encoding genes in Enterobacteriace, Pseudomonas aeruginosa, and Acinetobacter baumanii isolated from patients at Intensive Care Unit Cipto Mangunkusumo Hospital in 2011.

AIM: to determine the prevalence of carbapenemase encoding genes (blaIMP-1, blaVIM-2, blaKPC-2, blaOXA-48, and blaNDM-1) of carbapenem-resistant Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter baumanii isolated from the intensive care unit patients as pathogens, in Cipto Mangunkusumo hospital (ICU-RSCM) in 2011. METHODS: we examined the carbapenemase encoding genes in the clinical microbiology laboratory (LMK FKUI/RSCM). Duplex- and simplex PCR methods were conducted to detect the resistant genes. RESULTS: we found 4 (5%) P. aeruginosa strains carry blaIMP-1 gene and all were isolated from sputum specimens. The prevalence of carbapenem resistant among Gram-negative bacilli isolated from ICU-RSCM, are Enterobacteriaceae 27.6%, P. aeruginosa 21.9%, and A. baumannii 50.5%. The New Delhi Metallo--lactamase encoding gene (blaNDM-1) was detected in 1 K. pneumonia isolated from sputum as well. The other genes, i.e. blaKPC-2, blaVIM-2, and blaOXA-48 were not found in any isolates. The absence of other genes indicated that other mechanisms may play a role in the occurrence of carbapenem resistance in pathogens isolated in ICU-RSCM. CONCLUSION: this study confirmed that the prevalence of carbapenems resistant Gram-negative bacilli in ICU-RSCM in 2011 was high. The carbapenemase encoding genes, which were detected among the carbapenems resistant Gram-negative bacilli, were blaIMP-1 and blaNDM-1.

Phenotype characterization of Beta-lactamase producing enterobacteriaceae in the intensive care unit (ICU) of Cipto Mangunkusumo Hospital in 2011.

AIM: the goal of this study is to understand the phenotype characteristic of beta-lactamase enzymes producing Enterobacteriaceae, such as ESBL, AmpC, and carbapenemase. METHODS: three different methods are performed to confirm those phenotypic characteristics, namely double disk diffusion method to confirm ESBL, AmpC disk test (cefoxitin-based) to confirm AmpC, and modified Hodge test to confirm carbapenemase. RESULTS: using double disk diffusion method, we found 58.42% isolates are ESBL-producing, whereas the outcomes of AmpC disk test shows 1.98% are AmpC-producing. By conducting modified Hodge test (MHT), 27.59% isolates are confirmed as carbapenemase-producing bacteria. CONCLUSION: this study confirmed the prevalence of beta-lactamase producing Klebsiella pneumoniae is very high. Nevertheless, AmpC and carbapenemase should not be ignored despite their low prevalence.