Intestinal Carriage Research Articles

Antibiotic Susceptibility Patterns and Extended Spectrum Beta-Lactamase (ESBL) production in Enterobactericeae Isolated from Stool Samples of HIV and AIDS Patients in Ibadan, Nigeria

Background and Objectives: Abuse and indiscriminate use of antibiotics, prolong hospital admission, travel history, organ transplants, immunocompromised conditions and age are parts of the factors that contribute to development of antibiotic resistance and intestinal carriage of Extended Spectrum Beta-Lactamases (ESBL) Enterobacteriaceae. These bacteria affect the course and outcome of an infection and continue to pose a challenge to infection management worldwide. This study was carried out to determine the antimicrobial susceptibility patterns and prevalence of ESBL-producing Enterobacteriaceae isolated from stool samples of HIV and AIDS patients in Ibadan, Nigeria.
 Materials and Methods: One hundred stool samples were collected from consenting HIV and AIDS patients accessing care in Antiretroviral (ARV) Clinic in a secondary and a tertiary health care facility in Ibadan, Nigeria. Gram-negative bacteria were isolated and identified using conventional methods. Antimicrobial susceptibility test was carried out using the Kirby Bauer disc diffusion technique. Phenotypic detection of ESBL-producing isolates was carried out using Double Disc Synergy Test (DDST).
 Results: A total of 240 Gram-negative bacteria were isolated comprising 100 (41.6%) Escherichia coli, 33(13.8%) Klebsiella pneumonia, 27(11.3%) Serratia marcescens, 20(8.3%) Salmonella enterica, 9(3.8%) Proteus vulgaris, 13(5.4%) Proteus mirabilis, 21(8.8%) Citrobacter freundii and 17(7.1%) Enterobacter aerogenes. Out these, 56 (23.3%) were ESBL-producers; comprising 23(41.0%) Escherichia coli, 9(16.0%) Klebsiella pneumonia, 6(10.7%) Serratia marcescens, 5(8.9%) Salmonella enterica, 3(5.3%) Proteus vulgaris, 5(8.9%) Proteus mirabilis, 2(3.6%) Citrobacter freundii and 3(5.4%) Enterobacter aerogenes. Among the ESBL producers, 45 (80.3%) and 38 (67.8%) showed resistance to trimethoprim/sulfamethoxazole and aztreonam while 3 (3.5%) showed resistance to ertapenem. Also, 96.4% (54/56) of the ESBL producers were multidrug resistant.
 Conclusion: This study showed that HIV and AIDS patients are reservoirs of ESBL-producing Enterobacteriaceae through faecal carriage, presenting them as likely source of dissemination of ESBL producer in community and hospital settings.

Intense intestinal carriage and subsequent acquisition of multidrug-resistant enterobacteria in neonatal intensive care unit in Morocco.

This study was conducted in order to know the colonization rate of MDR enterobacteria in neonates during their hospitalization in neonatal intensive care unit (NICU). Furthermore, we investigated risk factors for potential colonization and molecular epidemiology of isolated resistant bacteria. This prospective study was carried out in the neonatology and intensive care unit department of the University Hospital of Fez (Morocco) from February 2013 to July 2015. All consecutive admitted newborns were screened for intestinal and nasal carriage of MDR enterobacteria at admission of the babies and during the hospitalization. During the study period, a total of 641 Enterobacteriaceae were isolated and Klebsiella pneumoniae was the predominated bacteria. Bacterial identification and antibiograms were performed according to the international standards. On admission, 455 newborns were screened. A median age of these newborns was 1 day with an extended 147 days and their average weight was 2612 ± 1023 grams. 22.4% of neonates were found colonized by an ESBL producing Enterobacteriaceae (ESBL-E), 8.7% by a carbapenemases producing Enterobacteriaceae (CPE). During hospitalization, 207 of newborns were included in the acquisition study. 59.4% of newborns acquired an ESBL-E during their stay, 12.5% has acquired CPE. The blaCTXM-15 gene was the most frequently detected (81.2%) among ESBL-E. While, all CPE has expressed the blaOXA-48 gene exclusively. Two risk factors have been significantly associated with MDR enterobacteria colonization at admission which are newborns admission from maternity of the university hospital (95% CI, 1.859–5.129, P = 0.000) and neurological distress (95% CI, 1.038 to 4.694, P = 0.040). During hospitalization, the none risk factor was significantly associated with the carriage of MDR-E. The high rate of colonization, the MDR enterobacteria and the resistance genes found represent good indicator of cross-transmission in the NICU. An active strategy to control the spread of MDR enterobacteria should be applied.

Does an Antibiotic Stewardship Applied in a Pig Farm Lead to Low ESBL Prevalence?

Background. The aim of the present study was to prospectively evaluate the prevalence of intestinal carriage of colistin-resistant and extended-spectrum β-lactamase (ESBL)-producing Enterobacterales among pigs from a Swiss farm attending an animal health and antibiotic stewardship program and to determine the associated mechanisms of resistance. Materials/Methods. Eighty-one fecal samples were recovered and screened for either β-lactam-resistant, colistin-resistant, or aminoglycoside-resistant Enterobacterales, using respective screening media. All recovered isolates were tested for antimicrobial susceptibility and their clonal relationship (PFGE and MLST). Plasmid typing was performed by plasmid-based replicon typing (PBRT). Resistance genes were searched by PCR and sequencing. Results. A total of 38 ESBL-producing Escherichia coli and a single ESBL-producing Enterobacter cloacae were recovered from 81 pigs, corresponding to a prevalence of 50%, no other β-lactamase producer being identified. Among the 38 ESBL-producing E. coli, all belonged to sequence type (ST) ST10, except two ST34 and ST744 isolates. Among the ST10-blaCTX-M-1 isolates, three subclones (n = 22, n = 13, and n = 1, respectively) were identified according to the PFGE analysis. The most commonly identified IncI1 plasmid harboring the blaCTX-M-1 gene was 143 kb in size and coharbored other resistance genes. Only three colistin-resistant Enterobacterales isolates were recovered, namely two Klebsiella pneumoniae isolates and a single E. cloacae isolate. Screening for the plasmid-borne mcr-1 to mcr-9 genes in these three isolates gave negative results. The two K. pneumoniae isolates were clonally related, belonged to ST76, and harbored a truncated mgrB chromosomal gene being the source of colistin resistance. Conclusion. A high prevalence of fecal carriage of ESBL-producing E. coli was found, being mainly caused by the spread of a clonal lineage within the farm. By contrast, a low prevalence of colistin-resistant Enterobacterales was found.

Monitoring antibiotic resistance profiles of faecal isolates of Enterobacteriaceae and the prevalence of carbapenem-resistant isolates among food handlers in Kuwait

Carbapenem-resistant Enterobacteriaceae (CRE) have become one of the most challenging problems in infectious diseases worldwide. Unrecognised personnel such as food handlers (FHs) colonised with CRE serve as a reservoir for transmission. This study assessed the prevalence and susceptibility patterns of CRE isolates from FHs working in commercial eateries in the community (CFHs) and healthcare settings (HCFHs) in Kuwait over the period 2016-2018. Representative colonies from faecal samples were identified by API 20E and a VITEK®2 ID System. Susceptibility testing against 21 antibiotics was performed by Etest and agar dilution. A total of 681 isolates of the family Enterobacteriaceae were isolated from 405 FHs, of which 425 (62.4%) were Escherichia coli and 126 (18.5%) were Klebsiella pneumoniae. The prevalence of CRE among FHs was 7.7% (31/405), comprising 32% CFHs (10/31) and 68% HCFHs (21/31). Ampicillin, tetracycline and cefalotin showed very poor activities against most isolates with resistance rates of 63.3%, 41.7% and 40.8%, respectively. The prevalence of multidrug-resistant (MDR) isolates was 30.5%, including 130 E. coli (30.6%) and 22 K. pneumoniae (17.5%). An alarming level of colistin resistance (11.3%) was noted. A significant proportion of FH isolates (13.2%) exhibited extended-spectrum β-lactamases (ESBL) phenotypes, including 80 E. coli (18.8%) and 5 K. pneumoniae (4.0%). This study revealed that asymptomatic intestinal carriage of CRE, including MDR and ESBL isolates, was relatively common in our community. It is conceivable that FHs may pose a significant risk to consumers for the acquisition and spread of resistant strains.

Occurrence of Salmonella in the Cattle Production in France.

Salmonella is among the most common foodborne pathogens worldwide, and can lead to acute gastroenteritis. Along with poultry, cattle production is recognized as an important source of human infection. Salmonella transmission from cattle to humans can occur through the environment, or through close contact with sick animals or their derived products. This study aimed to investigate the intestinal carriage of Salmonella spp. within French cattle production. A total of 959 cattle intestinal samples, from one of the largest French slaughterhouses, were analyzed. Isolated strains were genotyped by pulsed field gel electrophoresis (PFGE), and a sub-selection was taken by whole genome sequencing (WGS). Twenty-nine samples were positive for Salmonella spp., yielding an estimated prevalence of 3% in cattle production. Eight different Salmonella serotypes were found: Montevideo was the most prevalent (34%), followed by Mbandaka (24%) and Anatum (14%). PFGE genotyping allowed the clustering of Salmonella isolates according to their serotype. Within the clusters, some isolates presented 100% similarity. To investigate potential epidemiological links between them, WGS and core genome multilocus sequence typing (cgMLST) were used, revealing identical profiles between isolates originating from different areas and/or different animal breeds. This investigation provides new insights on Salmonella serotype epidemiology in cattle production in France.

Evaluation of Thymol-β-d-Glucopyranoside as a Potential Prebiotic Intervention to Reduce Carriage of Zoonotic Pathogens in Weaned and Feeder Pigs.

The gut of food-producing animals is a reservoir for foodborne pathogens. Thymol is bactericidal against foodborne pathogens but rapid absorption of thymol from the proximal gut precludes the delivery of effective concentrations to the lower gut where pathogens mainly colonize. Thymol-β-d-glucopyranoside is reported to be more resistant to absorption than thymol in everted jejunal segments and could potentially function as a prebiotic by resisting degradation and absorption in the proximal gut but being hydrolysable by microbial β-glycosidase in the distal gut. Previous in vitro studies showed bactericidal effects of thymol-β-d-glucopyranoside against Campylobacter, Escherichia coli, and Salmonella enterica serovar Typhimurium in the presence but not absence of intestinal microbes expressing β-glycosidase activity, indicating that hydrolysis was required to obtain antimicrobial activity. Presently, the oral administration of thymol-β-d-glucopyranoside was studied to examine the effects on intestinal carriage of Campylobacter, E. coli, and S. Typhimurium in swine. The effects of thymol-β-d-glucopyranoside or thymol on antimicrobial sensitivity of representative E. coli isolates and characterized Salmonella strains were also explored. Results from two in vivo studies revealed little antimicrobial effects of thymol-β-d-glucopyranoside on Campylobacter, E. coli, or S. Typhimurium in swine gut. These findings add credence to current thinking that hydrolysis and absorption of thymol-β-d-glucopyranoside and thymol may be sufficiently rapid within the proximal gut to preclude delivery to the distal gut. Antibiotic susceptibilities of selected bacterial isolates and strains were mainly unaffected by thymol. Further research is warranted to overcome obstacles, preventing the delivery of efficacious amounts of thymol-β-d-glucopyranoside to the lower gut.

Organic Cation Transporter 1 an Intestinal Uptake Transporter: Fact or Fiction?

Intestinal transporter proteins are known to affect the pharmacokinetics and in turn the efficacy and safety of many orally administered drugs in a clinically relevant manner. This knowledge is especially well-established for intestinal ATP-binding cassette transporters such as P-gp and BCRP. In contrast to this, information about intestinal uptake carriers is much more limited although many hydrophilic or ionic drugs are not expected to undergo passive diffusion but probably require specific uptake transporters. A transporter which is controversially discussed with respect to its expression, localization and function in the human intestine is the organic cation transporter 1 (OCT1). This review article provides an up-to-date summary on the available data from expression analysis as well as functional studies in vitro, animal findings and clinical observations. The current evidence suggests that OCT1 is expressed in the human intestine in small amounts (on gene and protein levels), while its cellular localization in the apical or basolateral membrane of the enterocytes remains to be finally defined, but functional data point to a secretory function of the transporter at the basolateral membrane. Thus, OCT1 should not be considered as a classical uptake transporter in the intestine but rather as an intestinal elimination pathway for cationic compounds from the systemic circulation.

Intestinal carriage of vancomycin\u2010resistant Enterococcus spp. among high\u2010risk patients in university hospitals in Serbia: first surveillance report

BackgroundThe screening for intestinal carriage of vancomycin-resistant Enterococcus spp. (VRE) among high risk patients in the Balkan region and molecular epidemiology of VRE is insufficiently investigated, yet it could be of key importance in infection control. The aim of this study was to provide baseline data on VRE intestinal carriage among high-risk patients in Serbian university hospitals, to determine the phenotypic/genotypic profiles of the isolated VRE, to obtain knowledge of local resistance patterns and bridge the gaps in current VRE surveillance.MethodsThe VRE reservoir was investigated using stool samples from 268 inpatients. Characterization of isolated VRE stains consisted of BD Phoenix system, genotypic identification, glycopeptide and quinupristin–dalfopristin (Q–D) resistance probing, virulence gene (esp, hyl, efaA, asa1, gelE, cpd) detection and MLVA. Biofilm formation was evaluated by the microtiter plate method.ResultsVRE carriage prevalence among at-risk patients was 28.7%. All VRE strains were vanA positive multidrug-resistant Enterococcus faecium (VRfm), harboring ermB-1 (38.9%), esp (84%), efaA (71.2%), hyl (54.5%), asa1 (23.4%), gelE and cpd (11.6%) each. Ability of biofilm production was detected in 20.8%. Genetic relatedness of the isolates revealed 13 clusters, heterogeneous picture and 25 unique MTs profiles.ConclusionThe obtained prevalence of VRE intestinal carriage among high-risk inpatients in Serbia is higher than the European average, with high percentage of multidrug resistance. The emergence of resistance to Q–D is of particular concern. Close monitoring of pattern of resistance and strict adherence to specific guidelines are urgently needed in Serbia.

The Intestinal Carriage of Plasmid-Mediated Colistin-Resistant Enterobacteriaceae in Tertiary Care Settings.

Background: In order to estimate the prevalence of plasmid borne colistin resistance and to characterize in detail the mcr-positive isolates, we carried out a sentinel testing survey on the intestinal carriage of plasmid-mediated colistin-resistant Enterobacteriaceae in hospitalized patients. Methods: Between June 2018 and September 2019, 1922 faecal samples from hospitalised patients were analysed by selective culture in presence of colistin (3.5 mg/L), and in parallel by direct detection of the mcr-1 to mcr-8 genes by qPCR. The mcr-positive isolates were characterised by whole-genome sequencing. Results: The prevalence of the mcr-1 gene was 0.21% (n = 4/1922); the mcr-2 to 8 genes were not detected. The mcr-1 gene was found to be localised in the IncX4 (n = 3) and IncHI2 (n = 1) plasmid type. One Escherichia coli isolate was susceptible to colistin due to the inactivation of the mcr-1 gene through the insertion of the IS2 element; however, the colistin resistance was inducible by culture in low concentrations of colistin. One human mcr-1 positive E. coli isolate was related genetically to the mcr-1 E. coli isolate derived from turkey meat of Czech origin. Conclusions: mcr-mediated colistin resistance currently poses little threat to patients hospitalised in Czech healthcare settings. The presence of the mcr-1 gene in the human population has a possible link to domestically produced, retail meat.

High Frequency of Enterocytozoon bieneusi Genotype WL12 Occurrence among Immunocompromised Patients with Intestinal Microsporidiosis.

Microsporidiosis is an emerging opportunistic infection causing severe digestive disorders in immunocompromised patients. The aim of this study was to investigate the prevalence of intestinal microsporidia carriage among immunocompromised patients hospitalized at a major hospital complex in the Tunis capital area, Tunisia (North Africa), and perform molecular epidemiology and population structure analyses of Enterocytozoon bieneusi, which is an emerging fungal pathogen. We screened 250 stool samples for the presence of intestinal microsporidia from 171 patients, including 81 organ transplant recipients, 73 Human Immunodeficiency Virus (HIV)-positive patients, and 17 patients with unspecified immunodeficiency. Using a nested PCR-based diagnostic approach for the detection of E. bieneusi and Encephalitozoon spp., we identified 18 microsporidia-positive patients out of 171 (10.5%), among which 17 were infected with E. bieneusi. Microsporidia-positive cases displayed chronic diarrhea (17 out of 18), which was associated more with HIV rather than with immunosuppression other than HIV (12 out of 73 versus 6 out of 98, respectively, p = 0.02) and correlated with extended hospital stays compared to microsporidia-negative cases (60 versus 19 days on average, respectively; p = 0.001). Strikingly, internal transcribed spacer (ITS)-based genotyping of E. bieneusi strains revealed high-frequency occurrence of ITS sequences that were identical (n = 10) or similar (with one single polymorphic site, n = 3) to rare genotype WL12. Minimum-spanning tree analyses segregated the 17 E. bieneusi infection cases into four distinct genotypic clusters and confirmed the high prevalence of genotype WL12 in our patient population. Phylogenetic analyses allowed the mapping of all 17 E. bieneusi strains to zoonotic group 1 (subgroups 1a and 1b/1c), indicating loose host specificity and raising public health concern. Our study suggests a probable common source of E. bieneusi genotype WL12 transmission and prompts the implementation of a wider epidemiological investigation.

Study Protocol: Seven vs. 14 days treatment for afebrile men with urinary tract infection

The optimal treatment duration for men with urinary tract infection (UTI) is poorly defined. Observational data suggests that shorter-duration therapy may perform as well as longer-duration therapy, but trial data are lacking. We present the protocol and methods for a Department of Veterans Affairs-funded trial of seven vs. 14 days of antimicrobial therapy for afebrile men with UTI, with the primary outcome of symptom resolution 14 days after completing active antimicrobial treatment. An optional sub-study will investigate the effect of treatment duration on the intestinal carriage of antimicrobial-resistant microorganisms. Subjects are enrolled after their UTI is diagnosed and treatment initiated, using a combination of in-person and mail enrollment to maximize participation and minimize resource utilization. This trial will provide high-quality evidence to guide the management of a common infectious disease and potentially limit unnecessary antimicrobial use.

Antibiotic-Resistant Gram-negative Bacteria Carriage in Healthcare Workers Working in an Intensive Care Unit.

Little is known about antibiotic-resistant Gram-negative bacteria (GNB) intestinal carriage among healthcare workers (HCWs) in Vietnam. All HCWs at a tertiary intensive care units were asked to undertake weekly rectal swabs. Among 40 participants, 65% (26/40) carried extended spectrum β-lactamases (ESBL)/AmpC β-lactamase-producing Escherichia coli. Two HCWs colonized with ESBL/AmpC β-lactamase-producing Klebsiella pneumoniae. One HCW colonized with Acinetobacter baumannii. No one carried Pseudomonas spp.. A quarter (10/40) of HCWs were identified as persistent and frequent carriers. There is an urgent need to screen antibiotic-resistant GNB among HCWs and improve HCWs’ hand hygiene compliance to reduce the transmission of antibiotic-resistant GNB in the hospital.

Asymptomatic Carriage of Salmonella and Intestinal Parasites in Pupils in Yaounde

Background: Feco-oral transmitted diseases (FOTD) remain a public health issue, particularly in developing countries. Data concerning the carriage of Salmonella and intestinal parasites in children are available worldwide but are lacking in Cameroon. This study aimed to determine the asymptomatic carriage of Salmonella and intestinal parasites in children of two primary schools in Yaoundé. Methods: A cross-sectional descriptive study was conducted from October 2017 to May 2018 in two primary schools (from rural and urban areas) in the 7th precinct of Yaoundé. Sociodemographic, clinical and paraclinical (rectal swab, direct examination of fresh stool and bacteriological culture on Hektoen medium) data were collected. Results: We included 368 (192 boys) pupils from both schools (184 in each school) with a mean age of 8.99 ± 2.21 years. None of the children was infected by Salmonella spp. Intestinal parasite prevalence was 9.80% (6.52% of children from the urban school vs 13.04% from the rural ones). The intestinal parasite prevalence tended to be higher in girls than in boys (11.98% vs. 7.39%). Among intestinal parasites, protozoa were the most widely found. Entamoeba histolytica and Giardia intestinalis were the most prevalent pathogenic intestinal protozoa (11.11% vs. 25% of all positive stool exams). The helminths, less frequent, were represented by Ascaris lumbicoides and Enterobius vermicularis. The factors associated with intestinal parasite carriage were mainly rural school location and age between 11 - 13 years. Conclusion: Among children in primary school, Salmonella infection was absent, while intestinal parasites are frequent, represented mostly by protozoa. This parasitism is in our cohort associated with the rural school location and the 11 - 13 years age group. This suggests that there is additional room for the implementation of prevention measures for intestinal parasite infections in our setting.

Characterization of an outbreak due to extended-spectrum β-lactamase-producing Klebsiella pneumoniae in a neonatal intensive care unit

Background: The epidemiological–microbiological characteristics and effective intervention measures in an outbreak due to extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae in a neonatal intensive care unit are described. Materials and methods: Cases from June 22, 2018 to February 11, 2019 were analyzed. Microbiological analysis of intestinal carriage of ESBL-producing K. pneumoniae and environmental samples was conducted. Strain relationships were studied by pulsed-field gel electrophoresis (PFGE). Results: A 35-week outbreak affecting 41 patients, with eight infected, 33 colonized, and two deceased patients occurred. Two stages of the outbreak were observed with differences in the frequency of intestinal carriage of ESBL-producing K. pneumoniae. The same genetic subtype was seen in patient strains and was different from strains isolated from the environment. Deficiencies in contact precautions, hand hygiene, and handling of breast milk were observed. Conclusions: A monoclonal outbreak by ESBL-producing K. pneumoniae that occurred in two phases and the different control measures in each of the stages is described. Effective control measures are mainly based on improving compliance with standard precautions and contact precautions, and other complementary measures are described such as proper handling of breast milk, periodic carriage studies, and the generation of three patient cohorts.

Urban Migrant Labourers as Potential Source for Transfer of Antimicrobial Resistance to Rural Community

The aim of the study was to investigate potential evidence for spread of antimicrobial resistance (AMR) from urban migrant labourers to labourers from local resident rural community due to sharing of common residential premises and other civic amenities. Two groups of unskilled labourers, enrolled for civil construction in a peri-urban area viz. (i) labourers having migrated from urban zone and (ii) labourers from local resident village community were compared in terms of demographic profile, history of various risk factors towards acquisition of AMR and prevalence of extended-spectrum beta-lactamase (ESBL), carbapenemase and New Delhi metallo-beta-lactamase type 1 (NDM-1) categories of AMR at enrolment and after one year of sharing of common residential premises with associated sanitation facilities using Escherichia coli as indicator organism. Higher percentage of urban migrant labourers were characterised by low literacy level, history of inhabitation in makeshift shelters without dedicated access to drinking water or cooking space, practice of defecation in open, episodes of illness suggestive of bacterial infections, faulty treatment seeking behaviour and intestinal carriage rate of E. coli with various categories of AMR compared to the non-migrant labourers from rural community. The later group showed an increase in the prevalence of carbapenem resistance with NDM-1 production during the duration of co-inhabitation with urban migrant labourers. The present study provided potential evidence for transfer of AMR by urban migrant labourers to non-migrant labourers from rural community that may serve as vehicle for further transmission of AMR to the rural community hitherto unexposed or less exposed to the problem.

Molecular characterization of Prototheca in 11 symptomatic dogs.

Protothecosis is an uncommon disease caused by algae of the genus Prototheca. In dogs, the infection is usually first localized to the colon but has the propensity to later disseminate hematogenously to many other organs, with marked tropism for the eyes and central nervous system. Diagnosis is established by culture and/or evidence of Prototheca organisms in cytologic or histologic preparations. Species characterization, however, requires molecular investigations. Our laboratory set up a real-time PCR targeting portion D1/D2 of the 28S rRNA for identification of Prototheca species from both positive cultures (of rectal swabs and urine) and formalin-fixed, paraffin-embedded tissue. Prototheca bovis, P. ciferrii, and P. wickerhamii were characterized in 11 dogs with systemic or cutaneous protothecosis. Prototheca identifications were phylogenetically consistent with the new taxonomy proposed for this genus based on the mitochondrial cytochrome b gene. As a pilot study, we screened feces and rectal scrapes from 200 asymptomatic dogs, using 2 cohorts of stray and owned animals, to determine the prevalence of intestinal carriage of Prototheca spp. The Prototheca-negative results from both cohorts of healthy dogs suggest that predisposing factors related to the host probably contribute more to the acquisition of clinical disease than exposure to contaminated environments.

Impact of systematic screening for AmpC-hyperproducing Enterobacterales intestinal carriage in intensive care unit patients

BackgroundEmpirical antimicrobial therapy (EAT) is a challenge for community-acquired, hospital-acquired and ventilator-associated pneumonia, particularly in the context of the increasing occurrence of third-generation cephalosporin-resistant Enterobacterales (3GCR-E), including extended-spectrum beta-lactamase Enterobacterales (ESBL-E) and high-level expressed AmpC cephalosporinase-producing Enterobacterales (HLAC-E). To prevent the overuse of broad-spectrum antimicrobial therapies, such as carbapenems, we assessed the performance of screening for intestinal carriage of HLAC-E in addition to ESBL-E to predict 3GCR-E (ESBL-E and/or HLAC-E) presence or absence in respiratory samples in ICU, and to evaluate its potential impact on carbapenem prescription.Materials and methodsThis monocentric retrospective observational study was performed in a surgical ICU during a 4-year period (January 2013–December 2016). Patients were included if they had a positive culture on a respiratory sample and a previous intestinal carriage screening performed by rectal swabbing within 21 days. Sensitivity, specificity, positive (PPV) and negative (NPV) predictive values and likelihood ratios were calculated for the screening for intestinal carriage of ESBL-E, HLAC-E and 3GCR-E (ESBL-E and/or HLAC-E) as predictor of their absence/presence in respiratory samples. Impact of HLAC-E and ESBL-E reporting on EAT was also studied.Results765 respiratory samples, retrieved from 468 patients, were analyzed. ESBL-E prevalence was 23.8% in rectal swab and 4.4% in respiratory samples. HLAC-E prevalence was 9.0% in rectal swabs and 3.7% in respiratory samples. Overall, the 3GCR-E prevalence was 31.8% in rectal swabs and 7.7% in respiratory samples. NPVs were 98.8%, 98.0% and 96.6% for ESBL-E, HLAC-E and 3GCR-E, respectively. Over the study period, empirical antimicrobial therapy was initiated for 315 episodes of respiratory infections: 228/315 (72.4%) were associated with negative intestinal carriage screening for both HLAC-E and ESBL-E, of whom 28/228 (12.3%) were treated with carbapenems. Of 23/315 (7.3%) cases with screening for positive intestinal carriage with HLAC-E alone, 10/23 (43.5%) were treated with carbapenems.ConclusionSystematic screening and reporting of HLAC-E in addition to ESBL-E in intestinal carriage screening could help to predict the absence of 3GCR-E in respiratory samples of severe surgical ICU patients. This could improve the appropriateness of EAT in ICU patients with HAP and may prevent the overuse of carbapenems.

Extended-Spectrum β-Lactamase- and Carbapenemase-Producing Enterobacterales Intestinal Carriage Among Outpatients: Microbiological and Epidemiological Differences Between Private Dwelling Residents and Nursing Home Residents.

The aim of this work was to assess the prevalence of carbapenemase-producing and extended-spectrum β-lactamase-producing Enterobacterales (ESBLPE) intestinal carriage among private dwelling residents (PDR) and nursing home residents (NHR) from the catchment area of Hospital Verge de la Cinta (Tortosa. North-Eastern Spain), and to depict clinicoepidemiological features of colonized individuals. Prevalence of ESBLPE carriage amid 762 PDR (0-94 years) who had feces collected for routine culture was 7.3% and 31% among 71 NHR (68-98 years) screened upon hospital admission. The mean age of colonized and noncolonized subjects was 30 and 32.8 years in PDR (p = 0.58) and 85 and 87 years in NHR (p = 0.32). The predominant ESBLPE was CTX-M-15-producing Escherichia coli (42.8% in PDR and 68.2% in NHR [25% and 86.7% belonging to O25b-ST131 clone; p < 0.0001]), followed by CTX-M-9-group- and SHV-producing E. coli and by CTX-M-15-producing Klebsiella pneumoniae. Overall, 72.7% of ESBLPE were multidrug resistant and 46.2% carried transferable quinolone determinants. Institutionalization in a nursing home was a risk factor for ESBLPE and extended-spectrum β-lactamase (ESBL)-producing O25b-ST131 E. coli carriage in individuals over 67 years (odds ratio 7.7 and 14.1). Previous antibiotic use and skin ulcers were significantly associated with ESBLPE carriage in NHR. Age <25 years in PDR and amoxicillin/clavulanate exposure in NHR protected against ESBL-producing O25b-ST131 E. coli colonization. Only two PDR, with known risk factors, bore OXA-48-producing isolates. These results highlight the role of nonhospitalized intestinal carriers, particularly NHR, as ESBLPE reservoirs and the preponderance of CTX-M-15, mainly linked to O25b-ST131 clone, as well as the emergence of carbapenemase-producing Enterobacterales carriers.

Clonal relatedness in the acquisition of intestinal carriage and transmission of multidrug resistant (MDR) Klebsiella pneumoniae and Escherichia coli and its risk factors among preterm infants admitted to the neonatal intensive care unit (NICU)

Gastrointestinal carriage of multidrug resistant (MDR) Gram-negative bacilli, especially Klebsiella pneumoniae and Escherichia coli, was highly associated with severe nosocomial infections. The main objectives of this study were to determine the clonal relatedness of intestinal carriage and transmission risk factors of MDR E. coli and K. pneumoniae amongst preterm infants admitted to the neonatal intensive care unit (NICU). A prospective cohort study of preterm infants with gestational age<37 weeks was conducted in the NICU of the University of Malaya Medical Centre (UMMC). Infants' stool specimens were collected on day 1 (meconium), week 1, week 2, week 8 and week 10 during their admission (from 1st June to 31st August 2017) until discharge. The presence and antibiotic resistance pattern of MDR E. coli and K. pneumoniae were determined. Strain clonality and relatedness were explored via pulsed-field gel electrophoresis (PFGE) fingerprints. The risk factors for MDR strains acquisition were evaluated using the Cox proportional-hazards model and Firth logistic regression. A total of 139 stool specimens were obtained from 50 subjects. Twenty-six (52%) infants were colonized with MDR K. pneumoniae and/or E. coli. High clonal dissemination between two clusters of ESBL-producing K. pneumoniae strains was seen from PFGE profile. We detected a persistent, dominant, aminoglycosides-resistant strains cluster (cluster B), which harbored blaTEM, blaSHV, blaOXA-1, blaCTX-M-1, ompK35 and ompK36 genes. Infants born to women who were anemic in pregnancy [OR=0.01 (CI=0.00-0.39), P-value=0.042] and infants exposed to penicillin/β-lactams group antibiotics during the first week of life [OR=0.02 (CI=0.02-0.32), P-value=0.013] were found to have a lower risk of MDR K. pneumoniae and E. coli colonization. The prevalence of dominant aminoglycosides-resistant strains cluster in the NICU is alarming. Awareness of and vigilance for the dominant cluster found will enable the reduction of cross-transmission amongst high-risk infants.

The global prevalence and trend of human intestinal carriage of ESBL-producing Escherichia coli in the community.

Intestinal colonization by ESBL Escherichia coli and its association with community-acquired MDR infections is of great concern. This review determined the worldwide prevalence of human faecal ESBL E. coli carriage and its trend in the community over the past two decades. A systematic literature search was conducted using PubMed, EMBASE and Google Scholar to retrieve articles published between 1 January 2000 and 13 February 2020 that contained data on the prevalence of faecal carriage of ESBL E. coli among healthy individuals. A cumulative (for the whole period) meta-analysis was used to estimate the global and regional pooled prevalence rates. Articles were grouped into study periods of 3 years, and subgroup meta-analyses were undertaken to examine the global pooled prevalence over time. Sixty-two articles covering 29 872 healthy persons were included in this meta-analysis. The cumulative (2003-18) global pooled prevalence of ESBL E. coli intestinal carriage in the community was 16.5% (95% CI 14.3%-18.7%; P < 0.001). The pooled prevalence showed an upward trend, increasing from 2.6% (95% CI 1.6%-4.0%) in 2003-05 to 21.1% (95% CI 15.8%-27.0%) in 2015-18. Over the whole period, the highest carriage rate was observed in South-East Asia (27%; 95% CI 2.9%-51.3%), while the lowest occurred in Europe (6.0%; 95% CI 4.6%-7.5%). Globally, an 8-fold increase in the intestinal carriage rate of ESBL E. coli in the community has occurred over the past two decades. Prevention of its spread may require new therapeutic and public health strategies.