First literature review of carbapenem-resistant Providencia

Dissemination of extensively drug-resistant NDM-producing Providencia stuartii in Europe linked to patients transferred from Ukraine, March 2022 to March 2023

BackgroundThe war in Ukraine led to migration of Ukrainian people. Early 2022, several European national surveillance systems detected multidrug-resistant (MDR) bacteria related to Ukrainian patients.AimTo investigate the genomic epidemiology of New Delhi metallo-β-lactamase (NDM)-producing Providencia stuartii from Ukrainian patients among European countries.MethodsWhole-genome sequencing of 66 isolates sampled in 2022-2023 in 10 European countries enabled whole-genome multilocus sequence typing (wgMLST), identification of resistance genes, replicons, and plasmid reconstructions. Five bla NDM-1-carrying-P. stuartii isolates underwent antimicrobial susceptibility testing (AST). Transferability to Escherichia coli of a bla NDM-1-carrying plasmid from a patient strain was assessed. Epidemiological characteristics of patients with NDM-producing P. stuartii were gathered by questionnaire.ResultswgMLST of the 66 isolates revealed two genetic clusters unrelated to Ukraine and three linked to Ukrainian patients. Of these three, two comprised bla NDM-1-carrying-P. stuartii and the third bla NDM-5-carrying-P. stuartii. The bla NDM-1 clusters (PstCluster-001, n = 22 isolates; PstCluster-002, n = 8 isolates) comprised strains from seven and four countries, respectively. The bla NDM-5 cluster (PstCluster-003) included 13 isolates from six countries. PstCluster-001 and PstCluster-002 isolates carried an MDR plasmid harbouring bla NDM-1, bla OXA-10, bla CMY-16, rmtC and armA, which was transferrable in vitro and, for some Ukrainian patients, shared by other Enterobacterales. AST revealed PstCluster-001 isolates to be extensively drug-resistant (XDR), but susceptible to cefiderocol and aztreonam-avibactam. Patients with data on age (n = 41) were 19-74 years old; of 49 with information on sex, 38 were male.ConclusionXDR P. stuartii were introduced into European countries, requiring increased awareness and precautions when treating patients from conflict-affected areas.

Identification of a novel Providencia species showing multi-drug-resistant in three patients with hospital-acquired infection

Providencia species are important opportunistic pathogens for humans and are associated with several infectious diseases. In this study, we found three clinical strains belonging to a novel Providencia species, namely Providencia huashanensis, including strains CRE-3FA-0001T, CRE-138-0026, and CRE-138-0111. These strains were recovered from three patients, and all of them were associated with nosocomial infections, including incision infection, urinary tract infection, and intracranial infection. The three strains showed high-level resistance to many types of antimicrobials, including amikacin, aztreonam, ceftazidime, cefepime, ciprofloxacin, colistin, polymyxin B, imipenem, meropenem, ceftazidime-avibactam, imipenem-relebactam. Investigation of the resistance mechanism revealed that acquired resistance genes such as blaKPC, blaNDM, blaPER, blaOXA, aac, ant, and qnrD, played an important role in the multidrug-resistant phenotype for the three strains. The phylogenetic trees were reconstructed based on the 16S rRNA gene sequences, multi-locus sequence analysis, and core single nucleotide polymorphisms. The genome sequence of the strains had a range of 83.5%-85.8% average nucleotide identity and 21%-25.5% in silico DNA-DNA hybridization scores with other Providencia type strains. The average nucleotide identity and in silico DNA-DNA hybridization values and the phylogenetic trees indicated that the strains CRE-3FA-0001T, CRE-138-0026, and CRE-138-0111 strains should be considered as a novel species of the genus Providencia, for which the name P. huashanensis sp. nov. is proposed. The type strain is CRE-3FA-0001T = China Center for Type Culture Collection AB 2023186T = Korean Collection for Type Cultures 8373T.

Identification of Providencia spp. clinical isolates co-producing carbapenemases IMP-27, OXA-24, and OXA-58 in Mexico

Providencia rettgeri, belonging to the genus Providencia, had gained significant interest due to its increasing prevalence as a common pathogen responsible for healthcare-associated infections in hospitals. P. rettgeri isolates producing carbapenemases have been reported to reduce the efficiency of carbapenems in clinical antimicrobial therapy. However, coexistence with other resistance determinants is rarely reported. The goal of this study was the molecular characterization of carbapenemase-producing Providencia spp. clinical isolates. Among 23 Providencia spp. resistant to imipenem, 21 were positive to blaNDM-1; one positive to blaNDM-1 and blaOXA-58 like; and one isolate co-producing blaIMP-27, blaOXA-24/40 like, and blaOXA-58 like were identified. We observed a low clonal relationship, and the incompatibility groups Col3M and ColRNAI were identified in the plasmid harboring blaNDM-1. We report for the first time a P. rettgeri strain co-producing blaIMP-27, blaOXA-24-like, and blaOXA-58 like. The analysis of these resistance mechanisms in carbapenemase co-producing clinical isolates reflects the increased resistance.

Environmental microbial colistin resistance in an elderly south Brazilian long-term care facility

Colistin resistance is a global health concern, with antibiotics being the last treatment for Gram-negative bacteria infections. We aimed to identify colistin-resistant enterobacteria on environmental surfaces of a long-term care facility (LTCF) for the elderly in southern Brazil. Samples were collected and screened on MacConkey agar plus colistin, followed by API20E identification and PCR. Two isolates were founded and identified as Klebsiella pneumoniae and Providencia stuartii harboring mcr-1 gene with MICs > 128 µg mL-1 for colistin. This is the first isolation of microorganisms resistant to colistin in the environment of a LTCF for the elderly in south Brazil, urging monitoring programs to reduce environmental contamination by multiresistant microorganisms.

Genomic landscape of NDM-1 producing multidrug-resistant Providencia stuartii causing burn wound infections in Bangladesh

The increasing antimicrobial resistance in Providencia stuartii (P. stuartii) worldwide, particularly concerning for immunocompromised and burn patients, has raised concern in Bangladesh, where the significance of this infectious opportunistic pathogen had been previously overlooked, prompting a need for investigation. The two strains of P. stuartii (P. stuartii SHNIBPS63 and P. stuartii SHNIBPS71) isolated from wound swab of two critically injured burn patients were found to be multidrug-resistant and P. stuartii SHNIBPS63 showed resistance to all the 22 antibiotics tested as well as revealed the co-existence of blaVEB-6 (Class A), blaNDM-1 (Class B), blaOXA-10 (Class D) beta lactamase genes. Complete resistance to carbapenems through the production of NDM-1, is indicative of an alarming situation as carbapenems are considered to be the last line antibiotic to combat this pathogen. Both isolates displayed strong biofilm-forming abilities and exhibited resistance to copper, zinc, and iron, in addition to carrying multiple genes associated with metal resistance and the formation of biofilms. The study also encompassed a pangenome analysis utilizing a dataset of eighty-six publicly available P. stuartii genomes (n = 86), revealing evidence of an open or expanding pangenome for P. stuartii. Also, an extensive genome-wide analysis of all the P. stuartii genomes revealed a concerning global prevalence of diverse antimicrobial resistance genes, with a particular alarm raised over the abundance of carbapenem resistance gene blaNDM-1. Additionally, this study highlighted the notable genetic diversity within P. stuartii, significant informations about phylogenomic relationships and ancestry, as well as potential for cross-species transmission, raising important implications for public health and microbial adaptation across different environments.

Genomic epidemiology and heterogeneity of Providencia and their blaNDM-1-carrying plasmids

Providencia as an opportunistic pathogen can cause serious infection, and moreover the emergence of multi-drug-resistant Providencia strains poses a potentially life-threatening risk to public health. However, a comprehensive genomic study to reveal the population structure and dissemination of Providencia is still lacking. In this study, we conducted a genomic epidemiology analysis on the 580 global sequenced Providencia isolates, including 257 ones sequenced in this study (42 ones were fully sequenced). We established a genome sequence-based species classification scheme for Providencia, redefining the conventional 11 Providencia species into seven genocomplexes that were further divided into 18 genospecies, providing an extensively updated reference for Providencia species discrimination based on the largest Providencia genome dataset to date. We then dissected the profile of antimicrobial resistance genes and the prevalence of multi-drug-resistant Providencia strains among these genocomplexes/genospecies, disclosing the presence of diverse and abundant antimicrobial resistance genes and high resistance ratios against multiple classes of drugs in Providencia. We further dissected the genetic basis for the spread of blaNDM-1 in Providencia. blaNDM-1 genes were mainly carried by five incompatible (Inc) groups of plasmids: IncC, IncW, IncpPROV114-NR, IncpCHS4.1-3, and IncpPrY2001, and the last three were newly designated in this study. By tracking the spread of blaNDM-1-carrying plasmids, IncC, IncpPROV114-NR, IncpCHS4.1-3, and IncpPrY2001 plasmids were found to be highly involved in parallel horizontal transfer or vertical clonal expansion of blaNDM-1 among Providencia. Overall, our study provided a comprehensive genomic view of species differentiation, antimicrobial resistance prevalence, and plasmid-mediated blaNDM-1 dissemination in Providencia.

Whole-Genome Sequence and Pathogenicity Analysis of Providencia Heimbachae Causing Diarrhea in Weaned Piglets

Providencia heimbachae was previously identified in piglets with post-weaned diarrhea and associated with hindlimb paralysis. However, the pathogenic mechanisms and virulence factors of P. heimbachae are not fully known. Whole-genome sequence analysis will be helpful to extend our understanding of the characterization of P. heimbachae at a genomic level. In this study, we sequenced the whole genome of P. heimbachae for the first time using PacBio RS II sequencers and assembled de novo through hierarchical genome assembly process (HGAP). Furthermore, we performed further genome annotation. The genome of P. heimbachae 99101 consists of a circular chromosome (4,262,828 bp) and a circular plasmid (231,957 bp) with G + C contents of 40.43 and 47.16%, respectively. Genome-wide sequence analysis yielded a total of 286 predicted virulence factors, 178 resistance genes, 17 chaperone protein manipulators of fimbriae, 47 genes involved in the encoding of flagellin, 12 cell membrane-associated virulence genes, 18 Enterobacteriaceae common antigens, etc. Based on genome analysis, we preliminarily confirmed through animal experiments that the capsule was the virulence factor of P. heimbachae causing hindlimb paralysis in animals. Our study provides a genetic basis for further elucidation of the characteristics and functional mechanisms of P. heimbachae as a conditionally pathogenic bacterium, as well as a direction for research into the mechanism of action of P. heimbachae infecting humans, extending knowledge of P. heimbachae as an important zoonotic pathogen.

Analysis of resistance genes of carbapenem-resistant Providencia rettgeri using whole genome sequencing

OBJECTIVE

This study aimed to investigate the clinical infection characteristics and analyze the resistance gene carrying status of carbapenem-resistant Providencia rettgeri via whole genome sequencing (WGS).

METHODS

Carbapenem-resistant P. rettgeri were collected from clinical patients between January 2020 and December 2021, and their susceptibility to 19 antimicrobial drugs was determined using the VITEK 2 Compact system and Kirby-Bauer (KB) disk diffusion method. The Illumina platform was used to perform WGS of the P. rettgeri isolates, and the resistance genes carried by the Carbapenem-resistant P. rettgeri strains were detected via ABRicate software. The phylogenetic tree was constructed by thirty-four strains including twenty-eight strains downloaded from NCBI database and the carbapenem-resistant six P. rettgeri strains in this study. Which based on genomic single nucleotide polymorphism (SNP) to understand the affinities of the carbapenem-resistant P. rettgeri strains.

RESULTS

Six carbapenem-resistant P. rettgeri strains were isolated from five different clinical departments using the blood, urine, sputum, and secretion specimens. These infected patients are middle-aged and elderly people with a history of severe trauma, tumors, hypertension, and various other underlying diseases, and invasive procedures. Antimicrobial sensitivity testing showed that all strains presented resistance to ampicillin-sulbactam, ceftazidime, ciprofloxacin, levofloxacin, and ertapenem, whereas they exhibited full susceptibility to cefepime and amikacin. Most strains demonstrated high resistance to β-lactams, aminoglycosides, and sulfonamides. Thirty-five resistance genes were identified by ABRicate. All carbapenem-resistant P. rettgeri strains carried aminoglycoside, fluoroquinolone, chloramphenicol, rifampicin, sulfonamide, and β-lactam resistance genes, and most importantly, all strains possessed the carbapenem resistance gene blaNDM-1. The six P. rettgeri strains in this study and the 28 carbapenem-resistant P. rettgeri strains from the NCBI database were divided into four evolutionary groups. The WF3643, WF3849, WF3822, and WF3821 strains in this study were in the same evolutionary group (clade A), while the closely related WF3099 and WF3279 strains were in different evolutionary groups (clade B and clade D), respectively. The WF3099 strain was distantly related to the other five strains.

CONCLUSION

Carbapenem-resistant P. rettgeri strains were mostly isolated from middle-aged and older patients with a history of surgery or serious underlying diseases, and they were found to cause multisystem infections. All Carbapenem-resistant P. rettgeri strains in this study carried blaNDM-1 and multiple antimicrobial drug resistance genes. Furthermore, the P. rettgeri strains in this study were closely related, suggesting the possibility of nosocomial infections. Therefore, our study highlights the need for research on P. rettgeri to control the spread of these nosocomial infections.

Detection of NDM-1 and OXA-10 Co-Producing Providencia rettgeri Clinical Isolate

Background

The coexistence of blaNDM-1 with other resistance determinants is rarely reported for Providencia rettgeri. Therefore, this study investigates the phenotypic and genetic characteristics of a multidrug-resistant P. rettgeri strain YQ150713.

Methods

P. rettgeri YQ150713 was identified as carrying blaNDM-1. S1-pulsed-field gel electrophoresis (S1-PFGE), Southern blotting, and conjugation experiments were used to determine plasmid characteristics. An antimicrobial susceptibility test was conducted. The complete genomic sequence of YQ150713 was obtained using Illumina NovaSeq 6000 and Oxford nanopore platforms. To further characterize the phylogenetic structure of P. rettgeri YQ150713, average nucleotide identity (ANI) and phylogenetic analyses were conducted.

Results

The S1-PFGE, Southern blot, and conjugation assays have confirmed that the isolate P. rettgeri YQ150713 contains the blaNDM-1 gene on a conjugative plasmid pYQ150713-NDM-1. Antimicrobial susceptibility testing has indicated that strain YQ150713 was resistant to various common antibiotics, except aztreonam and fosfomycin. Bioinformatics analysis has further shown that pYQ150713-NDM-1 was a novel plasmid with a size of 265,883 bp, and blaNDM-1 and blaOXA-10 were co-located on it. Phylogenetic analysis suggesting P. rettgeri has spread widely throughout the world.

Conclusion

In this study, blaNDM-1 and blaOXA-10 were co-localized on a novel plasmid pYQ150713-NDM-1 with a horizontal transfer function. To reduce the risk of the dissemination of such P. rettgeri isolates in clinical settings, more surveillance will be required in the future.

Hospital-acquired infections due to carbapenem-resistant Providencia stuartii

Background & objectives

During the course of a retrospective survey on healthcare associated infections (HAIs) due to carbapenem-resistant organisms, an unusual prevalence of HAIs due to carbapenem-resistant Providencia stuartii (CRPS) was found. Hence this study aimed to conduct the occurrence of P. stuartii associated HAIs with special reference to the drug resistance profiling of these isolates.

Methods

Of the eight total HAI cases (7.5% of total HAIs and 33.3% of HAIs due to Enterobacterales) of CRPS infections included in this study, three were reported from ventilator-associated pneumonia (VAP), three were surgical site infections (SSIs), one was a catheter-associated urinary tract infection (CAUTI) and one was a bloodstream infection. All the eight CRPS isolates were tested for extended-spectrum β-lactamases production, AmpC hyperproduction as well as carbapenem resistance. Typing of the isolates was performed by repetitive extragenic palindromic polymerase chain reaction (REP-PCR).

Results

All the eight isolates of CRPS were found to be AmpC hyperproducers, carbapenemase producers, and harboured chromosomally located blaNDM in seven isolates and blaIMP genes in one. All the cases with CRPS infections had prior history of colistin therapy along with prolonged hospital stay (>20 days). The cases were located in five different wards/intensive care unit (ICU) within the hospital in one year. However, strain typing by REP-PCR revealed 100 per cent similarity and clonal relatedness in all the seven isolates carrying blaNDM genes. Interestingly, routine hospital surveillance revealed a high carriage of P. stuartii in the axilla of patients admitted to the ICU.

Interpretation & conclusions

The study findings suggest CRPS as an important cause of HAIs. This organism often goes unnoticed due to the burden of carbapenem resistance in other Enterobacterales and non-fermenters.

Ocular Bacterial Infections: A Ten-Year Survey and Review of Causative Organisms Based on the Oklahoma Experience

Ocular infections can be medical emergencies that result in permanent visual impairment or blindness and loss of quality of life. Bacteria are a major cause of ocular infections. Effective treatment of ocular infections requires knowledge of which bacteria are the likely cause of the infection. This survey of ocular bacterial isolates and review of ocular pathogens is based on a survey of a collection of isolates banked over a ten-year span at the Dean McGee Eye Institute in Oklahoma. These findings illustrate the diversity of bacteria isolated from the eye, ranging from common species to rare and unique species. At all sampled sites, staphylococci were the predominant bacteria isolated. Pseudomonads were the most common Gram-negative bacterial isolate, except in vitreous, where Serratia was the most common Gram-negative bacterial isolate. Here, we discuss the range of ocular infections that these species have been documented to cause and treatment options for these infections. Although a highly diverse spectrum of species has been isolated from the eye, the majority of infections are caused by Gram-positive species, and in most infections, empiric treatments are effective.

The Diversity, Resistance Profiles and Plasmid Content of Klebsiella spp. Recovered from Dairy Farms Located around Three Cities in Pakistan

The rise of antimicrobial resistance (AMR) in bacterial pathogens such as Klebsiella pneumoniae (Kp) is a pressing public health and economic concern. The 'One-Health' framework recognizes that effective management of AMR requires surveillance in agricultural as well as clinical settings, particularly in low-resource regions such as Pakistan. Here, we use whole-genome sequencing to characterise 49 isolates of Klebisella spp. (including 43 Kp) and 2 presumptive Providencia rettgeri isolates recovered from dairy farms located near 3 cities in Pakistan-Quetta (n = 29), Faisalabad (n = 19), and Sargodha (n = 3). The 43 Kp isolates corresponded to 38 sequence types (STs), and 35 of these STs were only observed once. This high diversity indicates frequent admixture and limited clonal spread on local scales. Of the 49 Klebsiella spp. isolates, 41 (84%) did not contain any clinically relevant antimicrobial resistance genes (ARGs), and we did not detect any ARGs predicted to encode resistance to carbapenems or colistin. However, four Kp lineages contained multiple ARGs: ST11 (n = 2), ST1391-1LV (n = 1), ST995 (n = 1) and ST985 (n = 1). STs 11, 1391-1LV and 995 shared a core set of five ARGs, including blaCTX-M-15, harboured on different AMR plasmids. ST985 carried a different set of 16 resistance genes, including blaCTX-M-55. The two presumptive P. rettgeri isolates also contained multiple ARGs. Finally, the four most common plasmids which did not harbour ARGs in our dataset were non-randomly distributed between regions, suggesting that local expansion of the plasmids occurs independently of the host bacterial lineage. Evidence regarding how dairy farms contribute to the emergence and spread of AMR in Pakistan is valuable for public authorities and organizations responsible for health, agriculture and the environment, as well as for industrial development.

Conjugation of plasmid harboring bla NDM-1 in a clinical Providencia rettgeri strain through the formation of a fusion plasmid

Providencia rettgeri has recently gained increased importance owing to the New Delhi metallo-β-lactamase (NDM) and other β-lactamases produced by its clinical isolates. These enzymes reduce the efficiency of antimicrobial therapy. Herein, we reported the findings of whole-genome sequence analysis and a comprehensive pan-genome analysis performed on a multidrug-resistant P. rettgeri 18004577 clinical strain recovered from the urine of a hospitalized patient in Shandong, China, in 2018. Providencia rettgeri 18004577 was found to have a genome assembly size of 4.6 Mb with a G + C content of 41%; a circular plasmid p18004577_NDM of 273.3 Kb, harboring an accessory multidrug-resistant region; and a circular, stable IncT plasmid p18004577_Rts of 146.2 Kb. Additionally, various resistance genes were identified in its genome, including bla _NDM-1, bla _OXA-10, bla _PER-4, aph(3')-VI, ant(2'')-Ia, ant(3')-Ia, sul1, catB8, catA1, mph(E), and tet. Conjugation experiments and whole-genome sequencing revealed that the bla _NDM-1 gene could be transferred to the transconjugant via the formation of pJ18004577_NDM, a novel hybrid plasmid. Based on the genetic comparison, the main possible formation process for pJ18004577_NDM was the insertion of the [ΔISKox2-IS26-ΔISKox2]-aph(3')-VI-bla _NDM-1 translocatable unit module from p18004577_NDM into plasmid p18004577_Rts in the Russian doll insertion structure (ΔISKox2-IS26-ΔISKox2), which played a role similar to that of IS26 using the "copy-in" route in the mobilization of [aph(3')-VI]-bla _NDM-1. The array, multiplicity, and diversity of the resistance and virulence genes in this strain necessitate stringent infection control, antibiotic stewardship, and periodic resistance surveillance/monitoring policies to preempt further horizontal and vertical spread of the resistance genes. Roary analysis based on 30 P. rettgeri strains pan genome identified 415 core, 756 soft core, 5,744 shell, and 12,967 cloud genes, highlighting the "close" nature of P. rettgeri pan-genome. After a comprehensive pan-genome analysis, representative biological information was revealed that included phylogenetic distances, presence or absence of genes across the P. rettgeri bacteria clade, and functional distribution of proteins. Moreover, pan-genome analysis has been shown to be an effective approach to better understand P. rettgeri bacteria because it helps develop various tailored therapeutic strategies based on their biological similarities and differences.

Complete Genome Sequence of Providencia stuartii CMC-4104, Isolated from a Human Splenic Abscess, Containing Multiple Copies of NDM-1 and PER-1 Carbapenem Resistance Genes

We report the complete genome sequence of a clinical isolate of Providencia stuartii strain CMC-4104, isolated from a splenic abscess. Oxford Nanopore Technologies (ONT) and Illumina sequencing reads were assembled using Geneious to generate a 4,504,925-bp circular chromosome containing multiple copies of the NDM-1 and PER-1 genes in a genomic resistance island.

Investigation of factors related to biofilm formation in Providencia stuartii

Providencia stuartii is one of the Enterobacteriaceae species of medical importance commonly associated with urinary infections, which can also cause other ones, including uncommon ones, such as liver abscess and septic vasculitis. This bacterium stands out in the expression of intrinsic and acquired resistance to antimicrobials. Besides, it uses mechanisms such as biofilm for its persistence in biotic and abiotic environments. This study investigated the cellular hydrophobicity profile of clinical isolates of P. stuartii. It also analyzed genes related to the fimbrial adhesin in this species comparing with other reports described for other bacteria from Enterobacteriaceae family. The investigated isolates to form biofilm and had a practically hydrophilic cell surface profile. However, fimH and mrkD genes were not found in P. stuartii, unlike observed in other species of Enterobacteriaceae. These results show that P. stuartii has specificities regarding its potential for biofilm formation, which makes it difficult to destabilize the infectious process and increases the permanence of this pathogen in hospital units.

Emergence and Evolution of Unique Plasmids Harboring blaIMP-70 and blaCTX-M-253 in Multidrug-Resistant Providencia rettgeri

Although the prevalence of carbapenem-resistant Enterobacterales remains low in Japan, these bacteria are a growing problem worldwide, owing to their multidrug resistance phenotype. We isolated a multidrug-resistant Providencia rettgeri strain, NR1418, harboring a rare bla_IMP variant, bla_IMP-70, a novel bla_CTX-M variant, designated bla_CTX-M-253, and bla_MOX-1. This strain is resistant to β-lactams, amikacin, levofloxacin, and colistin. Genomic analysis revealed that NR1418 carries two plasmids, designated pNR1418-1 and pNR1418-2. The pNR1418-1 plasmid harbors bla_CTX-M-253, bla_TEM-1, and bla_MOX-1, while the pNR1418-2 plasmid harbors bla_IMP-70, which is located in a class 1 integron. Both plasmids exhibit high similarities with the plasmid of the P. rettgeri isolate BML2526, which also harbors bla_IMP-70 and was identified in the same region of Japan as NR1418 at a different point in time. This indicates the possibility of the emergence and evolution of IMP-70-producing P. rettgeri and suggests that the plasmid of BML2526 may have occurred following recombination of the two plasmids harbored by NR1418. Further, bla_IMP-70 and bla_CTX-M-253 were found on unique plasmids, indicating that they likely evolved through mutations and recombination. IMPORTANCE Although Providencia rettgeri is an opportunistic pathogen, its intrinsic resistance to colistin and tigecycline makes the treatment of carbapenem-resistant P. rettgeri challenging. We isolated a multidrug-resistant P. rettgeri strain which harbored a rare bla_IMP variant, bla_IMP-70, a novel bla_CTX-M variant, bla_CTX-M-253, and bla_MOX-1 from a urinary sample obtained in Osaka, Japan. We investigated its genetic structure and evaluated the evolution of the plasmids carrying these genes. We show that bla_IMP-70, bla_CTX-M-253, and bla_MOX-1 are present on unique plasmids and that they have high similarities to the plasmid of another IMP-70-producing P. rettgeri isolate that was identified as being from the same location. The evolution of plasmids through mutations and recombination may play a role in the development and spread of multidrug resistance.

Providencia Causing UTIs: Are We Reaching a Dead End!!!

Background

Materials and methods

Results

Conclusion

How to cite this article

Identification and Characterization of vB_PreP_EPr2, a Lytic Bacteriophage of Pan-Drug Resistant Providencia rettgeri

Providencia rettgeri is an emerging opportunistic Gram-negative pathogen with reports of increasing antibiotic resistance. Pan-drug resistant (PDR) P. rettgeri infections are a growing concern, demonstrating a need for the development of alternative treatment options which is fueling a renewed interest in bacteriophage (phage) therapy. Here, we identify and characterize phage vB_PreP_EPr2 (EPr2) with lytic activity against PDR P. rettgeri MRSN 845308, a clinical isolate that carries multiple antibiotic resistance genes. EPr2 was isolated from an environmental water sample and belongs to the family Autographiviridae, subfamily Studiervirinae and genus Kayfunavirus, with a genome size of 41,261 base pairs. Additional phenotypic characterization showed an optimal MOI of 1 and a burst size of 12.3 ± 3.4 PFU per bacterium. EPr2 was determined to have a narrow host range against a panel of clinical P. rettgeri strains. Despite this fact, EPr2 is a promising lytic phage with potential for use as an alternative therapeutic for treatment of PDR P. rettgeri infections.

Association of Proteus mirabilis and Providencia stuartii Infections with Diabetes

Background and Objectives: Proteus and Providencia are related genera of opportunistic pathogens belonging to the Morganellaceae family, often a cause of infections in the immunocompromised hosts, such as diabetic patients. Their clinical significance has increased due to their intrinsic resistance to polymyxins, which is often associated with acquired resistance mechanisms. In this study we evaluated the infections caused by Proteus mirabilis and Providencia stuartii in two groups of patients, with diabetes (group 1) and without diabetes (group 2) admitted to the intensive care unit and surgical wards. The infections were investigated in terms of infection type, risk factors, clinical course, predictive factors for unfavourable outcomes and antibiotic resistance profile. Materials and Methods: An observational, retrospective, cross-sectional study was conducted, comprising all patients infected with these pathogens. Bacterial identification and antibiotic sensitivity testing were performed using the Vitek2C automated system. Results: Comparison of the two groups showed that the statistically significant common infectious risk factors were found less frequently among diabetic patients when compared with non-diabetic patients, and that antimicrobial resistance was significantly lower in the diabetic patient group. However, survival rates did not differ between the two groups, drawing attention to the implications of diabetes as comorbidity. Additionally, with regard to the antibiotic resistance profile, 38.89% of P. stuartii strains isolated from diabetic patients belonged to the difficult-to-treat (DTR) phenotype, contributing to the severity of these infections compared with those caused by P. mirabilis, of which 32% were wild type strains and 0% were DTR phenotype. The DTR/extended spectrum beta-lactamase producing P. stuartii isolates more than doubled the risk of mortality, while the presence of nasogastric nutrition tripled the risk. Conclusions: P. stuartii infections that occurred in diabetic patients proved to be more difficult to treat, the majority of them being healthcare-associated bacteremias.

Providencial Progression: Time to be Intolerant

How to cite this article: Gopal P. Providencial Progression: Time to be Intolerant. Indian J Crit Care Med 2022;26(4):409-410.

Genomic analysis of the nomenclatural type strain of the nematode-associated entomopathogenic bacterium Providencia vermicola

Background

Enterobacteria of the genus Providencia are mainly known as opportunistic human pathogens but have been isolated from highly diverse natural environments. The species Providencia vermicola comprises insect pathogenic bacteria carried by entomoparasitic nematodes and is investigated as a possible insect biocontrol agent. The recent publication of several genome sequences from bacteria assigned to this species has given rise to inconsistent preliminary results.

Results

The genome of the nematode-derived P. vermicola type strain DSM_17385 has been assembled into a 4.2 Mb sequence comprising 5 scaffolds and 13 contigs. A total of 3969 protein-encoding genes were identified. Multilocus sequence typing with different marker sets revealed that none of the previously published presumed P. vermicola genomes represents this taxonomic species. Comparative genomic analysis has confirmed a close phylogenetic relationship of P. vermicola to the P. rettgeri species complex. P. vermicola DSM_17385 carries a type III secretion system (T3SS-1) with probable function in host cell invasion or intracellular survival. Potentially antibiotic resistance-associated genes comprising numerous efflux pumps and point-mutated house-keeping genes, have been identified across the P. vermicola genome. A single small (3.7 kb) plasmid identified, pPVER1, structurally belongs to the qnrD-type family of fluoroquinolone resistance conferring plasmids that is prominent in Providencia and Proteus bacteria, but lacks the qnrD resistance gene.

Conclusions

The sequence reported represents the first well-supported published genome for the taxonomic species P. vermicola to be used as reference in further comparative genomics studies on Providencia bacteria. Due to a striking difference in the type of injectisome encoded by the respective genomes, P. vermicola might operate a fundamentally different mechanism of entomopathogenicity when compared to insect-pathogenic Providencia sneebia or Providencia burhodogranariea. The complete absence of antibiotic resistance gene carrying plasmids or mobile genetic elements as those causing multi drug resistance phenomena in clinical Providencia strains, is consistent with the invertebrate pathogen P. vermicola being in its natural environment efficiently excluded from the propagation routes of multidrug resistance (MDR) carrying genetic elements operating between human pathogens. Susceptibility to MDR plasmid acquisition will likely become a major criterion in the evaluation of P. vermicola for potential applications in biological pest control.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-08027-w.

A Multi-Point Surveillance for Antimicrobial Resistance Profiles among Clinical Isolates of Gram-Negative Bacteria Recovered from Major Ha'il Hospitals, Saudi Arabia

The devastating nosocomial resistance is an on-going global concern. Surveillance of resistance is crucial for efficient patient care. This study was aimed to conduct a surveillance in four major Ha'il Hospitals from September to December 2020. Using a multipoint program, records of 621 non-duplicate Gram-negative cultures were tested across 21 drugs belonging to different categories. Major species were Klebsiella pneumoniae (n = 187, 30%), E. coli (n = 151, 24.5%), Pseudomonas aeruginosa, (n = 84, 13.6%), Acinetobacter baumannii (n = 82, 13.3%), and Proteus mirabilis (n = 46, 7%). Based on recent resistance classifications, A. baumanni, P. aeruginosa, and enteric bacteria were defined as pan-resistant, extremely resistant, and multi-drug resistant, respectively. A. baumannii (35%) and K. pneumoniae (23%) dominated among coinfections in SARS-CoV2 patients. The "other Gram-negative bacteria" (n = 77, 12.5%) from diverse sources showed unique species-specific resistance patterns, while sharing a common Gram-negative resistance profile. Among these, Providencia stuartii was reported for the first time in Ha'il. In addition, specimen source, age, and gender differences played significant roles in susceptibility. Overall infection rates were 30% in ICU, 17.5% in medical wards, and 13.5% in COVID-19 zones, mostly in male (59%) senior (54%) patients. In ICU, infections were caused by P. mirabilis (52%), A. baumannii (49%), P. aeruginosa (41%), K. pneumoniae (24%), and E. coli (21%), and most of the respiratory infections were caused by carbapenem-resistant A. baumannii and K. pneumoniae and UTI by K. pneumoniae and E. coli. While impressive IC, hospital performances, and alternative treatment options still exist, the spread of resistant Gram-negative bacteria is concerning especially in geriatric patients. The high selective SARS-CoV2 coinfection by A. baumannii and K. pneumoniae, unlike the low global rates, warrants further vertical studies. Attributes of resistances are multifactorial in Saudi Arabia because of its global partnership as the largest economic and pilgrimage hub with close social and cultural ties in the region, especially during conflicts and political unrests. However, introduction of advanced inter-laboratory networks for genome-based surveillances is expected to reduce nosocomial resistances.

First Genome Description of Providencia vermicola Isolate Bearing NDM-1 from Blood Culture

In this paper, we describe the first complete genome sequence of Providencia vermicola species, a clinical multidrug-resistant strain harboring the New Delhi Metallo-β-lactamase-1 (NDM-1) gene, isolated at the Kinshasa University Teaching Hospital, in Democratic Republic of the Congo. Whole genome sequencing of an imipenem-resistant clinical Gram-negative P. vermicola P8538 isolate was performed using MiSeq and Gridion, and then complete genome analysis, plasmid search, resistome analysis, and comparative genomics were performed. Genome assembly resulted in a circular chromosome sequence of 4,280,811-bp and 40.80% GC and a circular plasmid (pPV8538_NDM-1) of 151,684-bp and 51.93%GC, which was identified in an Escherichia coli P8540 strain isolated in the same hospital. Interestingly, comparative genomic analysis revealed multiple sequences acquisition within the P. vermicola P8538 chromosome, including three complete prophages, a siderophore biosynthesis NRPS cluster, a Type VI secretion system (T6SS), a urease gene cluster, and a complete Type-I-F CRISPR-Cas3 system. Β-lactamase genes, including bla_CMY-6 and bla_NDM-1, were found on the recombinant plasmid pPV8538_NDM-1, in addition to other antibiotic resistance genes such as rmtC, aac6’-Ib3, aacA4, catA1, sul1, aac6’-Ib-cr, tetA, and tetB. Genome comparison with Providencia species revealed 82.95% of average nucleotide identity (ANI), with P. stuartii species exhibiting 90.79% of proteome similarity. We report the first complete genome of P. vermicola species and for the first time the presence of the bla_NDM-1 gene in this species. This work highlights the need to improve surveillance and clinical practices in DR Congo in order to reduce or prevent the spread of such resistance.

Occurrence and Transmission of bla NDM-Carrying Enterobacteriaceae from Geese and the Surrounding Environment on a Commercial Goose Farm

We investigated the prevalence and transmission of NDM-producing Enterobacteriaceae in fecal samples of geese and environmental samples from a goose farm in southern China. The samples were cultivated on MacConkey agar plates supplemented with meropenem. Individual colonies were examined for bla _NDM, and bla _NDM-positive bacteria were characterized based on whole-genome sequencing (WGS) data from the Illumina and Oxford Nanopore Technologies (ONT) platforms. Of 117 samples analyzed, the carriage rates for New Delhi metallo-β-lactamase (NDM)-positive Enterobacteriaceae were 47.1, 18, and 50% in geese, inanimate environments (sewage, soil, fodder, and dust), and mouse samples, respectively. Two variants (bla _NDM-1 and bla _NDM-5, in 4 and 40 isolates, respectively) were found among 44 bla _NDM-positive Enterobacteriaceae; these variants belonged to eight species, and Escherichia coli was the most prevalent (50%). WGS analysis revealed that bla _NDM coexisted with diverse antibiotic resistance genes (ARGs). Population structure analysis showed that most E. coli and Enterobacter sp. isolates were highly heterogeneous, while most Citrobacter sp. and P. stuartii isolates possessed extremely high genetic similarities. In addition, bla _NDM-5-positive ST4358/ST48 E. coli isolates were found to be clonally spread between geese and the environment and were highly genetically similar to those reported from ducks, farm environments, and humans in China. Plasmid analysis indicated that IncX3 pHNYX644-1-like (n = 40) and untypeable pM2-1-like plasmids (n = 4) mediated bla _NDM spread. pM2-1-like plasmids possessed diverse ARGs, including bla _NDM-1, the arsenical and mercury resistance operons, and the maltose operon. Our findings revealed that the goose farm is a reservoir for NDM-positive Enterobacteriaceae The bla _NDM contamination of wild mice and the novel pM2-1-like plasmid described here likely adds to the risk for dissemination of bla _NDM and associated resistance genes.IMPORTANCE Carbapenem-resistant bacteria, in particular NDM-producing Enterobacteriaceae, have become a great threat to global public. These bacteria have been found not only in hospital and community environments but also among food animal production chains, which are recognized as reservoirs for NDM-producing Enterobacteriaceae However, the dissemination of NDM-producing bacteria in waterfowl farms has been less well explored. Our study demonstrates that the horizontal spread of bla _NDM-carrying plasmids and the partial clonal spread of bla _NDM-positive Enterobacteriaceae contribute to the widespread contamination of bla _NDM in the goose farm ecosystem, including mice. Furthermore, we found a novel and transferable bla _NDM-1-carrying multidrug resistance (MDR) plasmid that possessed multiple environmental adaptation-related genes. The outcomes of this study contribute to a better understanding of the prevalence and transmission of bla _NDM-carrying Enterobacteriaceae among diverse niches in the farm ecosystem.

Difficult to Treat Proteeae strains in high risk Romanian hospital departments

Introduction: Resistance to first-line antibiotics of the Proteeae strains within the difficult-to-treat (DTR) phenotype is a cause of limitation of therapeutic options. The study aimed to characterize these strains, to identify the factors that influence their acquisition and the predictive factors for the patient’s evolution.

Material and methods: Between July 2017 and January 2019, 400 of Proteeae strains were isolated from samples of patients admitted to intensive care units (ICUs) and surgical wards of a university hospital in Romania. The identification and testing of antibiotic sensitivity was performed using the Vitek 2 Compact system. The DTR phenotype was defined as the resistance (or intermediate resistance) to all categories of β-lactams, carbapenems and fluoroquinolones.

Results: Out of 400 Proteeae strains, 21% were of the DTR type, most of them from the species Providencia stuartii and Proteus mirabilis, identified predominantly on the ICUs. The excess fatality in the DTR subsample compared to the non-DTR subsample was 16.37%. The multivariate analysis identified as independent risk factors: the number of antibiotics administered, the number of days of urinary catheterization, the presence of tracheostomy, nasogastric nutrition, respectively belonging to the species P. stuartii. The probabilities of survival were reduced by the presence of the central venous catheter (CVC), tracheostomy, by the increase of the number of hospitalization days respectively of the number of antibiotics administered.

Conclusion: The DTR phenotype in the case of Proteeae strains has been associated especially with the species P. stuartii, with invasive exogenous factors and with an increased fatality.

Isolation of Morganella Morganii and Providencia Species from Clinical Samples in a Tertiary Care Hospital in North India

INTRODUCTION

The members of the tribe Proteeae, Morganella and Providencia are being increasingly recognized as important pathogens. The spectrum of disease caused by them is wide and in reported cases, the mortality is high. Previously both of these pathogens were considered to be rare pathogens as the potential to cause nosocomial transmission and infection was not much studied. But their phenomenal evolution and increase in multidrug-resistance (MDR) strains of these pathogens are posing a major threat toward public health throughout the world.

METHODS

This present study was carried out from July 2018 to December 2018 on all the pus and body fluid samples that were received in the Department of Microbiology. Samples were processed as per the standard Microbiological guidelines and also were analyzed for their antimicrobial susceptibility profile as per Clinical Laboratory Standards Institute.

RESULTS

Out of 8425 samples received, 2140 were culture positive, amongst which 19 samples (0.89%) were positive for Providencia species (9) and Morganella morganii(10). The male : female ratio of these 19 patients was 2.8 : 1 and maximum patients (13) belonged to 20-60 years. As far as risk factors are concerned, maximum patients were diabetics (7) followed by abnormal liver function tests (6), concomitant UTI (6), history of invasive procedure (5), prior exposure to antibiotics (5) and urinary catheterization (4). About 6 were polymicrobial infections. Antibiotic susceptibility patterns revealed that Providencia strains were sensitive to ampicillin- sulbactum (77.7%) and amikacin (77.7%), while all Morganella strains were 100% sensitive to tobramycin and piperacillintazobactam.

CONCLUSION

This study heralds in need for more research in this area as infections caused by these two pathogens are on the rise. Moreover, resistance to antimicrobials is also an increasingly common problem thus delaying the treatment and prognosis of the disease.

Distribution of NDM1 Carbapenemase-Producing Proteeae Strains on High-Risk Hospital Wards

Background

Carbapenem-resistant Proteeae (CRP) is a group of multidrug-resistant (MDR) microorganisms that raise special treatment problems due to their intrinsic resistance to colistin. In this study, our aim is to provide a phenotypic and molecular characterization of the carbapenemases secreted by CRP strains isolated from inpatients from an intensive care unit (ICU) and surgical wards, as well as the identification of the risk factors involved in their acquisition.

Methods

An observational, cross-sectional study was performed which included all Proteeae strains isolated in samples from inpatients on high-risk wards of the largest university hospital in Western Romania, from July 2017 to April 2019. Meropenem-resistant strains (N=65) with MIC ≥16 µg/mL were subjected to a singleplex PCR assay for the detection of blaNDM, blaVIM and blaCTX-M genes. The analysis of risk factors was performed by logistic regression.

Results

Out of 8317 samples that were processed, 400 Proteeae strains were isolated: 64% belonging to the genus Proteus, 26.75% to the genus Providencia and 9.25% to the genus Morganella. Most CRP strains (N=56) were of MBL type, and 55 had the blaNDM gene as the prevalent gene substrate. P. stuartii was the main species that provided the circulating MDR strains. Most CRP strains came from patients admitted to ICU, being isolated mainly from bronchial aspirates and blood cultures. Multivariate analysis revealed 3 independent risk factors – mechanical ventilation>96h (HR: 40.51 [13.65–120.25], p <0.001), tracheostomy (HR: 2.65 [1.14–6.17], p = 0.024) and prolonged antibiotic therapy (HR: 1.01 [1.00–1.02], p = 0.03).

Conclusion

There is a significant increase in the incidence of CR P. stuartii strains, the MBL-blaNDM type being predominant. These strains presented various other resistance mechanisms, being often extremely difficult to treat and led to an excess of lethality of 27.16%.

First report of the aac(6')-Ib-cr gene in Providencia stuartii isolates in Brazil

INTRODUCTION

The aac(6')-Ib-cr and bla KPC genes are spreading among Enterobacteriaceae species, including Providencia stuartii, in some countries of world.

METHODS

These genes were investigated in 28 P. stuartii isolates from a public hospital in Recife, Pernambuco, Brazil, by PCR and sequencing.

RESULTS

The aac(6')-Ib-cr gene was detected in 16 resistant isolates, and the bla KPC gene was seen in 14.

CONCLUSIONS

The presence of these genes in P. stuartii multi- and extensively drug-resistant isolates indicates that the resistance arsenal of this species is increasing, thus limiting the therapeutic options.

Comparative Genomic Analysis Reveals Genetic Mechanisms of the Variety of Pathogenicity, Antibiotic Resistance, and Environmental Adaptation of Providencia Genus

The bacterial genus Providencia is Gram-negative opportunistic pathogens, which have been isolated from a variety of environments and organisms, ranging from humans to animals. Providencia alcalifaciens, Providencia rettgeri, and Providencia stuartii are the most common clinical isolates, however, these three species differ in their pathogenicity, antibiotic resistance and environmental adaptation. Genomes of 91 isolates of the genus Providencia were investigated to clarify their genetic diversity, focusing on virulence factors, antibiotic resistance genes, and environmental adaptation genes. Our study revealed an open pan-genome for the genus Providencia containing 14,720 gene families. Species of the genus Providencia exhibited different functional constraints, with the core genes, accessory genes, and unique genes. A maximum-likelihood phylogeny reconstructed with concatenated single-copy core genes classified all Providencia isolates into 11 distant groups. Comprehensive and systematic comparative genomic analyses revealed that specific distributions of virulence genes, which were highly homologous to virulence genes of the genus Proteus, contributed to diversity in pathogenicity of Providencia alcalifaciens, Providencia rettgeri, and Providencia stuartii. Furthermore, multidrug resistance (MDR) phenotypes of isolates of Providencia rettgeri and Providencia stuartii were predominantly due to resistance genes from class 1 and 2 integrons. In addition, Providencia rettgeri and Providencia stuartii harbored more genes related to material transport and energy metabolism, which conferred a stronger ability to adapt to diverse environments. Overall, our study provided valuable insights into the genetic diversity and functional features of the genus Providencia, and revealed genetic mechanisms underlying diversity in pathogenicity, antibiotic resistance and environmental adaptation of members of this genus.

Emergence of Carbapenem-Resistant Providencia rettgeri and Providencia stuartii Producing IMP-Type Metallo-β-Lactamase in Japan

Four Providencia rettgeri isolates and one Providencia stuartii isolate were obtained from urine samples of five patients in 2018 in Japan. All of the isolates were resistant to imipenem and meropenem, and three were highly resistant to both carbapenems, with MICs of 512 μg/ml. The three highly carbapenem-resistant isolates harbored bla_IMP-70, encoding a variant of IMP-1 metallo-β-lactamase with two amino acid substitutions (Val67Phe and Phe87Val), and the other two harbored bla_IMP-1 and bla_IMP-11, respectively. Whole-genome sequencing revealed that an isolate harbored two copies of bla_IMP-1 on the chromosome and that the other four harbored a copy of bla_IMP-11 or bla_IMP-70 in a plasmid. Expression of bla_IMP-70 conferred carbapenem resistance in Escherichia coli Recombinant IMP-70 and an IMP-1 variant with Val67Phe but without Phe87Val had significant higher hydrolytic activities against meropenem than recombinant IMP-1, indicating that an amino acid substitution of Val67Phe affects increased activities against meropenem in IMP-70. These results suggest that Providencia spp. become more highly resistant to carbapenems by acquisition of two copies of bla_IMP-1 or by mutation of bla_IMP genes with amino acid substitutions, such as bla_IMP-70.

Genomic Analysis of two NDM-1 Providencia stuartii Strains Recovered from a Single Patient

In the last years, an increasing number of untreatable infections caused by drug-resistant microbes have impacted the health care system. Worldwide, infections caused by carbapenem-resistant (CR) Gram-negative bacilli have dramatically increased. Among the CR-Gram-negative bacilli, those producing carbapenemases, such as NDM-1, are the main concern. Different Enterobacterales harboring NDM-1 have been reported lately. Providencia stuartii, a member of the Morganellaceae family, is ubiquitous in the environment, but is also known to cause nosocomial infections. Here we describe the genomic analysis of two NDM-1- producing P. stuartii strains recovered from the same patient as well as other carbapenem resistant strains recovered from the same hospital. As a result of the genomic analysis thirteen resistance genes, including three to β-lactams (bla_OXA-1, bla_TEM-1, bla_NDM-1), four to aminoglycosides (aphA6, aac(3)-IId, aac(2')-Ia, aac(6')-Ib-cr5), one to sulfonamides (sul1), two to chloramphenicol (catB3, catA3), one to rifampicin, one to bleomycin (ble), and one to tetracycline (tet(B)) were found. Moreover, a variety of mobile genetic elements, such as insertion sequences, plasmids and phage- related sequences, were found within P. stuartii genomes. The spread of carbapenem-resistant isolates remains a significant clinical and public health concern. Therefore, we considered that the detection of CR isolates is an essential step in addressing this problem.

Genomic analysis of a multidrug-resistant clinical Providencia rettgeri (PR002) strain with the novel integron ln1483 and an A/C plasmid replicon

Whole-genome sequence analysis was performed on a multidrug-resistant Providencia rettgeri PR002 clinical strain isolated from the urine of a hospitalized patient in Pretoria, South Africa, in 2013. The resistome, mobilome, pathogenicity island(s), as well as virulence and heavy-metal resistance genes of the isolate, were characterized using whole-genome sequencing and bioinformatic analysis. PR002 had a genome assembly size of 4,832,624 bp with a GC content of 40.7%, an A/C₂ plasmid replicase gene, four integrons/gene cassettes, 17 resistance genes, and several virulence and heavy metal resistance genes, confirming PR002 as a human pathogen. A novel integron, In1483, harboring the gene bla_OXA-2 , was identified, with other uncharacterized class 1 integrons harboring aacA4cr and dfrA1. Aac(3')-IIa and bla_SCO-1 , as well as bla_PER-7 , sul2, and tet(B), were found bracketed by composite Tn3 transposons, and IS91, IS91, and IS4 family insertion sequences, respectively. PR002 was resistant to all antibiotics tested except amikacin, carbapenems, cefotaxime-clavulanate, ceftazidime-clavulanate, cefoxitin, and fosfomycin. PR002 was closely related to PR1 (USA), PRET_2032 (SPAIN), DSM_1131, and NCTC7477 clinical P. rettgeri strains, but not close enough to suggest it was imported into South Africa from other countries. Multidrug resistance in P. rettgeri is rare, particularly in clinical settings, making this case an important incident requiring urgent attention. This is also the first report of an A/C plasmid in P. rettgeri. The array, multiplicity, and diversity of resistance and virulence genes in this strain are concerning, necessitating stringent infection control, antibiotic stewardship, and periodic resistance surveillance/monitoring policies to preempt further horizontal and vertical spread of these resistance genes.

Present and Future of Carbapenem-resistant Enterobacteriaceae (CRE) Infections

Carbapenem-resistant Enterobacteriaceae (CRE) have become a public health threat worldwide. There are three major mechanisms by which Enterobacteriaceae become resistant to carbapenems: enzyme production, efflux pumps and porin mutations. Of these, enzyme production is the main resistance mechanism. There are three main groups of enzymes responsible for most of the carbapenem resistance: KPC (Klebsiella pneumoniae carbapenemase) (Ambler class A), MBLs (Metallo-ß-Lactamases) (Ambler class B) and OXA-48-like (Ambler class D). KPC-producing Enterobacteriaceae are endemic in the United States, Colombia, Argentina, Greece and Italy. On the other hand, the MBL NDM-1 is the main carbapenemase-producing resistance in India, Pakistan and Sri Lanka, while OXA-48-like enzyme-producers are endemic in Turkey, Malta, the Middle-East and North Africa. All three groups of enzymes are plasmid-mediated, which implies an easier horizontal transfer and, thus, faster spread of carbapenem resistance worldwide. As a result, there is an urgent need to develop new therapeutic guidelines to treat CRE infections. Bearing in mind the different mechanisms by which Enterobacteriaceae can become resistant to carbapenems, there are different approaches to treat infections caused by these bacteria, which include the repurposing of already existing antibiotics, dual therapies with these antibiotics, and the development of new ß-lactamase inhibitors and antibiotics.

Dissemination of NDM-1 carbapenemase-producer Providencia stuartii strains in Romanian hospitals: a multicentre study

Several Romanian hospitals have noted increasing isolation of Providencia stuartii strains in recent years, with an alarming rate of carbapenem resistance. In order to provide molecular epidemiological data regarding their dissemination, 77 P. stuartii strains collected from five hospitals located in different regions of Romania were analysed. All strains harboured IncA/C plasmid, and 67 carried the blaNDM-1 gene. Six clonal clusters were differentiated by pulsed-field gel electrophoresis. The predominant subtype was found in all five hospitals. Our study highlights the need for efficient infection-control measures, the optimization of antibiotic use and the targeted surveillance for carbapenemase-producing P. stuartii.

First report of carbapenem-resistant Providencia stuartii in Saudi Arabia

We present the case of 31-year-old man who developed hospital-acquired pneumonia in the intensive care unit. Pathogens were identified to be carbapenem-resistant isolates of Providencia stuartii and Klebsiella pneumoniae. The patient was treated with an extended infusion of double-dose meropenem (targeting the carbapenem-resistant P. stuartii) and colistin (targeting the carbapenem-resistant K. pneumoniae) for 2 weeks. The patient's disease responded well to the prescribed regimen; his chest X-ray became normal, and all other signs of infection subsided. To our knowledge, this is the first description of the emergence of carbapenem-resistant P. stuartii due to AmpC hyperproduction in Saudi Arabia.