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BACKGROUND: Inflammatory Bowel Diseases (IBD) are a major public health issue with unclear aetiology. Changes in the composition and functionality of the intestinal microbiota are associated with these pathologies, including the depletion of strict anaerobes such as Feacalibacterium prausnitzii. Less evidence is observed for depletion in other anaerobes, among which bifidobacteria. This study characterized the taxonomic and functional diversity of bifidobacteria isolated from the human intestinal microbiota in active and non-active IBD patients by a culturomics approach and evaluated if these bifidobacteria might be used as probiotics for gut health. RESULTS: A total of 341 bifidobacteria were isolated from the intestinal microbiota of IBD patients (52 Crohn's disease and 26 ulcerative colitis patients), with a high proportion of Bifidobacterium dentium strains (28% of isolated bifidobacteria). In ulcerative colitis, the major species identified was B. dentium (39% of isolated bifidobacteria), in active and non-active ulcerative colitis. In Crohn's disease, B. adolescentis was the major species isolated from non-active patients (40%), while similar amounts of B. dentium and B. adolescentis were found in active Crohn's disease patients. The relative abundance of B. dentium was increased with age, both in Crohn's disease and ulcerative colitis and active and non-active IBD patients. Antibacterial capacities of bifidobacteria isolated from non-active ulcerative colitis against Escherichia coli LF82 and Salmonella enterica ATCC 14028 were observed more often compared to strains isolated from active ulcerative colitis. Finally, B. longum were retained as strains with the highest probiotic potential as they were the major strains presenting exopolysaccharide synthesis, antibacterial activity, and anti-inflammatory capacities. Antimicrobial activity and EPS synthesis were further correlated to the presence of antimicrobial and EPS gene clusters by in silico analysis. CONCLUSIONS: Different bifidobacterial taxonomic profiles were identified in the microbiota of IBD patients. The most abundant species were B. dentium, mainly associated to the microbiota of ulcerative colitis patients and B. adolescentis, in the intestinal microbiota of Crohn's disease patients. Additionally, the relative abundance of B. dentium significantly increased with age. Furthermore, this study evidenced that bifidobacteria with probiotic potential (antipathogenic activity, exopolysaccharide production and anti-inflammatory activity), especially B. longum strains, can be isolated from the intestinal microbiota of both active and non-active Crohn's disease and ulcerative colitis patients.
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Bifidobacterium , Microbioma Gastrointestinal , Probióticos , Humanos , Bifidobacterium/aislamiento & purificación , Bifidobacterium/clasificación , Bifidobacterium/genética , Adulto , Femenino , Masculino , Persona de Mediana Edad , Enfermedades Inflamatorias del Intestino/microbiología , Adulto Joven , Anciano , Colitis Ulcerosa/microbiología , Enfermedad de Crohn/microbiología , Filogenia , Heces/microbiología , ARN Ribosómico 16S/genética , Fenotipo , Adolescente , Antibacterianos/farmacologíaRESUMEN
The therapeutic management of Crohn's disease (CD), a chronic relapsing-remitting inflammatory bowel disease (IBD), is highly challenging. Surgical resection is sometimes a necessary procedure even though it is often associated with postoperative recurrences (PORs). Tofacitinib, an orally active small molecule Janus kinase inhibitor, is an anti-inflammatory drug meant to limit PORs in CD. Whereas bidirectional interactions between the gut microbiota and the relevant IBD drug are crucial, little is known about the impact of tofacitinib on the gut microbiota. The HLA-B27 transgenic rat is a good preclinical model used in IBD research, including for PORs after ileocecal resection (ICR). In the present study, we used shotgun metagenomics to first delineate the baseline composition and determinants of the fecal microbiome of HLA-B27 rats and then to evaluate the distinct impact of either tofacitinib treatment, ileocecal resection or the cumulative effect of both interventions on the gut microbiota in these HLA-B27 rats. The results confirmed that the microbiome of the HLA-B27 rats was fairly different from their wild-type littermates. We demonstrated here that oral treatment with tofacitinib does not affect the gut microbial composition of HLA-B27 rats. Of note, we showed that ICR induced an intense loss of bacterial diversity together with dramatic changes in taxa relative abundances. However, the oral treatment with tofacitinib neither modified the alpha-diversity nor exacerbated significant modifications in bacterial taxa induced by ICR. Collectively, these preclinical data are rather favorable for the use of tofacitinib in combination with ICR to address Crohn's disease management when considering microbiota.
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Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , Microbiota , Piperidinas , Pirimidinas , Ratas , Animales , Enfermedad de Crohn/tratamiento farmacológico , Enfermedad de Crohn/cirugía , Enfermedad de Crohn/complicaciones , Ratas Transgénicas , Antígeno HLA-B27 , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/complicaciones , Manejo de la EnfermedadRESUMEN
BACKGROUND: The microbiological safety of donor milk (DM) is commonly ensured by Holder pasteurization (HoP, 62.5 °C for 30 min) in human milk banks despite its detrimental effects on bioactive factors. We compared the antimicrobial properties of DM after Holder pasteurization treatment or High Hydrostatic Pressure processing (HHP, 350 MPa at 38 °C), a non-thermal substitute for DM sterilization. METHODS: We assessed lactoferrin and lysozyme concentrations in raw, HHP- and HoP-treated pools of DM (n = 8). The impact of both treatments was evaluated on the growth of Escherichia coli and Group B Streptococcus in comparison with control media (n = 4). We also addressed the effect of storage of HHP treated DM over a 6-month period (n = 15). RESULTS: HHP milk demonstrated similar concentrations of lactoferrin compared with raw milk, while it was significantly decreased by HoP. Lysozyme concentrations remained stable regardless of the condition. Although a bacteriostatic effect was observed against Escherichia coli at early timepoints, a sharp bactericidal effect was observed against Group B Streptococcus. Unlike HoP, these results were significant for HHP compared to controls. Stored DM was well and safely preserved by HHP. CONCLUSION: Our study demonstrates that this alternative sterilization method shows promise for use with DM in human milk banks. IMPACT: Antimicrobial activity of donor milk after High Hydrostatic Pressure treatment has not been clearly evaluated. Donor milk lactoferrin is better preserved by High Hydrostatic Pressure than conventional Holder pasteurization, while lysozyme concentration is not affected by either treatment. As with Holder pasteurization, High Hydrostatic Pressure preserves donor milk bacteriostatic activity against E. coli in addition to bactericidal activity against Group B Streptococcus. Donor milk treated by High Hydrostatic Pressure can be stored safely for 6 months.
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Escherichia coli , Presión Hidrostática , Lactoferrina , Bancos de Leche Humana , Leche Humana , Muramidasa , Pasteurización , Pasteurización/métodos , Leche Humana/química , Humanos , Muramidasa/análisis , Escherichia coli/crecimiento & desarrollo , Lactoferrina/análisis , Esterilización/métodos , Streptococcus agalactiae , Microbiología de AlimentosRESUMEN
INTRODUCTION: The GeneXpert® MRSA/SA SSTI (Methicillin Resistant Staphylococcus aureus/S. aureus skin and soft tissue infection) PCR test allows early detection of methicillin resistance in staphylococci. This test was developed for skin infections and has been evaluated for prosthetic joint infections but, to our knowledge, has not been evaluated for hardware infections outside of arthroplasties. Furthermore, we conducted a retrospective study in patients with non-prosthetic osteosynthesis hardware aiming: (1) to identify the diagnostic values of the PCR test compared to conventional cultures and the resulting rate of appropriate antibiotic therapy; (2) to identify the rate of false negative (FN) results; (3) to identify and compare the rates of failure of infectious treatment (FN versus others); (4) to search for risk factors for FN of the PCR test. HYPOTHESIS: The PCR test allowed early and appropriate targeting of antibiotic therapy. MATERIAL AND METHODS: The results of PCR tests and conventional cultures for osteoarticular infections of non-prosthetic hardware over four years (2012-2016) were compared to identify the diagnostic values of using the results of conventional culture as a reference and the rate of appropriate antibiotic therapies. Infectious management failures between the results of the FN group and the others were compared, and variables associated with a FN of the PCR test were identified. RESULTS: The analysis of 419 PCR tests allowed us to establish a sensitivity of 42.86%, a specificity of 96.82%, a positive predictive value of 60% and a negative predictive value of 93.83%. Using the results of the PCR test for the targeting of postoperative antibiotic therapy, it was suitable for staphylococcal coverage in 90.94% (381/419). The rates of patients for whom infectious treatment failed were not significantly different between the FN group and the other patients (20.8% versus 17.7%, respectively; Hazard Ratio=1.12 (95%CI 0.47-2.69, p=0.79)). A skin opening during the initial trauma (p=0.005) and a polymicrobial infection were significantly associated with a risk of FN from the PCR test (p<0.001). CONCLUSION: The PCR test makes it possible to reduce the duration of empirical broad-spectrum antibiotic therapy during the treatment of an infection of osteosynthesis hardware but causes a lack of antibiotic coverage in 9.06% of cases. LEVEL OF EVIDENCE: III; diagnostic case control study.
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The rise of antimicrobial resistance has led to renewed interest in evaluating phage therapy. In murine models highly effective treatment of acute pneumonia caused by Pseudomonas aeruginosa relies on the synergistic antibacterial activity of bacteriophages with neutrophils. Here, we show that depletion of alveolar macrophages (AM) shortens the survival of mice without boosting the P. aeruginosa load in the lungs. Unexpectedly, upon bacteriophage treatment, pulmonary levels of P. aeruginosa were significantly lower in AM-depleted than in immunocompetent mice. To explore potential mechanisms underlying the benefit of AM-depletion in treated mice, we developed a mathematical model of phage, bacteria, and innate immune system dynamics. Simulations from the model fitted to data suggest that AM reduce bacteriophage density in the lungs. We experimentally confirmed that the in vivo decay of bacteriophage is faster in immunocompetent compared to AM-depleted animals. These findings demonstrate the involvement of feedback between bacteriophage, bacteria, and the immune system in shaping the outcomes of phage therapy in clinical settings.
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BACKGROUND: Bacteria and their viruses, bacteriophages, are the most abundant entities of the gut microbiota, a complex community of microorganisms associated with human health and disease. In this ecosystem, the interactions between these two key components are still largely unknown. In particular, the impact of the gut environment on bacteria and their associated prophages is yet to be deciphered. RESULTS: To gain insight into the activity of lysogenic bacteriophages within the context of their host genomes, we performed proximity ligation-based sequencing (Hi-C) in both in vitro and in vivo conditions on the 12 bacterial strains of the OMM12 synthetic bacterial community stably associated within mice gut (gnotobiotic mouse line OMM12). High-resolution contact maps of the chromosome 3D organization of the bacterial genomes revealed a wide diversity of architectures, differences between environments, and an overall stability over time in the gut of mice. The DNA contacts pointed at 3D signatures of prophages leading to 16 of them being predicted as functional. We also identified circularization signals and observed different 3D patterns between in vitro and in vivo conditions. Concurrent virome analysis showed that 11 of these prophages produced viral particles and that OMM12 mice do not carry other intestinal viruses. CONCLUSIONS: The precise identification by Hi-C of functional and active prophages within bacterial communities will unlock the study of interactions between bacteriophages and bacteria across conditions (healthy vs disease). Video Abstract.
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Bacteriófagos , Profagos , Ratones , Humanos , Animales , Profagos/genética , Ecosistema , Bacteriófagos/genética , Genómica , Cromosomas , Bacterias/genéticaRESUMEN
INTRODUCTION: The relationship between the occurrence of a periprosthetic hip or knee joint infection, a post-surgical hematoma and the time to surgical revision, along with the need to take samples for microbiology analysis has not been clearly defined. This led us to perform a retrospective study to: 1) define the rate of infected hematoma and subsequent infection after surgical revision for hematoma and 2) analyze in which time frame the hematoma was likely to be infected. HYPOTHESIS: The more time elapsed before the postoperative hematoma is drained surgically after hip or knee replacement, the higher the hematoma infection rate and the late infection rate. PATIENTS AND METHODS: Between 2013 and 2021, 78 patients (48 hip and 30 knee replacements) who had a postoperative hematoma without signs of infection upon draining were included in the study. Surgeons decided whether samples for microbiology were collected (33/78 patients (42%)). The data compiled consisted of the patient's demographics, the risk factors for infection, number of infected hematomas, number of subsequent infections at a minimum follow-up of 2 years, and the time to revision surgery (lavage). RESULTS: Of the 27 samples collected from the hematoma during the first lavage, 12/27 (44%) were infected. Of the 51 that did not have samples collected initially, 6/51 (12%) had them collected during the second lavage; 5 were infected and 1 was sterile. Overall, 17/78 (22%) of the hematomas were infected. Conversely, there were no late infections at a mean follow-up of 3.8 years (min 2, max 8) after the hematoma was drained in any of the 78 patients. The median time to revision was 4 days (Q1=2, Q3=14) for non-infected hematomas that were drained surgically versus 15 days (Q1=9, Q3=20) for hematomas that were found to be infected (p=0.005). No hematoma was infected when it was drained surgically within 72hours post-arthroplasty (0/19 (0%)). The infection rate went up to 2/16 (12.5%) when it was drained 3 to 5 days later and 15/43 (35%) when it was drained after more than 5 days (p=0.005). We believe this justifies collecting microbiology samples immediately when the hematoma is drained more than 72hours after the joint replacement procedure. Diabetes was more prevalent in patients who had an infected hematoma (8/17 [47%] versus 7/61 [11.5%], p=0.005). The infection was due to a single bacterium in 65% of cases (11/17); S. epidermidis was found in 59% (10/17) of infections. CONCLUSION: The occurrence of a hematoma after hip or knee replacement that requires surgical revision is associated with increased risk of infection, since the hematoma infection rate was 22%. Since hematomas drained within 72hours are less likely to be infected, samples do not need to be collected for microbiology at that time. Conversely, any hematomas being drained surgically beyond this time point should be considered as infected, thus microbiology samples should be collected, and empirical postoperative antibiotic therapy initiated. Early revision may prevent the occurrence of late infections. The standard treatment of infected hematomas appears to resolve the infection at a minimum follow-up of 2 years. LEVEL OF EVIDENCE: Level IV Retrospective study.
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Artroplastia de Reemplazo de Cadera , Infecciones Relacionadas con Prótesis , Humanos , Estudios Retrospectivos , Reoperación/efectos adversos , Estudios de Seguimiento , Infecciones Relacionadas con Prótesis/etiología , Artroplastia de Reemplazo de Cadera/efectos adversos , Hematoma/etiología , Hematoma/cirugíaRESUMEN
BACKGROUND: Postoperative recurrence (POR) after ileocecal resection (ICR) affects most Crohn's disease patients within 3-5 years after surgery. Adherent-invasive Escherichia coli (AIEC) typified by the LF82 strain are pathobionts that are frequently detected in POR of Crohn's disease and have a potential role in the early stages of the disease pathogenesis. Saccharomyces cerevisiae CNCM I-3856 is a probiotic yeast reported to inhibit AIEC adhesion to intestinal epithelial cells and to favor their elimination from the gut. AIM: To evaluate the efficacy of CNCM I-3856 in preventing POR induced by LF82 in an HLA-B27 transgenic (TgB27) rat model. METHODS: Sixty-four rats [strain F344, 38 TgB27, 26 control non-Tg (nTg)] underwent an ICR at the 12th wk (W12) of life and were sacrificed at the 18th wk (W18) of life. TgB27 rats were challenged daily with oral administration of LF82 (109 colony forming units (CFUs)/day (d), n = 8), PBS (n = 5), CNCM I-3856 (109 CFUs/d, n = 7) or a combination of LF82 and CNCM I-3856 (n = 18). nTg rats receiving LF82 (n = 5), PBS (n = 5), CNCM I-3856 (n = 7) or CNCM I-3856 and LF82 (n = 9) under the same conditions were used as controls. POR was analyzed using macroscopic (from 0 to 4) and histologic (from 0 to 6) scores. Luminal LF82 quantifications were performed weekly for each animal. Adherent LF82 and inflammatory/regulatory cytokines were quantified in biopsies at W12 and W18. Data are expressed as the median with the interquartile range. RESULTS: nTg animals did not develop POR. A total of 7/8 (87%) of the TgB27 rats receiving LF82 alone had POR (macroscopic score ≥ 2), which was significantly prevented by CNCM I-3856 administration [6/18 (33%) TgB27 rats, P = 0.01]. Macroscopic lesions were located 2 cm above the anastomosis in the TgB27 rats receiving LF82 alone and consisted of ulcerations with a score of 3.5 (2 - 4). Seven out of 18 TgB27 rats (39%) receiving CNCM I-3856 and LF82 had no macroscopic lesions. Compared to untreated TgB27 animals receiving LF82 alone, coadministration of CNCM I-3856 and LF82 significantly reduced the macroscopic [3.5 (2 - 4) vs 1 (0 - 3), P = 0.002] and histological lesions by more than 50% [4.5 (3.3 - 5.8) vs 2 (1.3 - 3), P = 0.003]. The levels of adherent LF82 were correlated with anastomotic macroscopic scores in TgB27 rats (r = 0.49, P = 0.006), with a higher risk of POR in animals having high levels of luminal LF82 (71.4% vs 25%, P = 0.02). Administration of CNCM I-3856 significantly reduced the levels of luminal and adherent LF82, increased the production of interleukin (IL)-10 and decreased the production of IL-23 and IL-17 in TgB27 rats. CONCLUSION: In a reliable model of POR induced by LF82 in TgB27 rats, CNCM I-3856 prevents macroscopic POR by decreasing LF82 infection and gut inflammation.
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Enfermedad de Crohn , Infecciones por Escherichia coli , Ratas , Animales , Enfermedad de Crohn/patología , Escherichia coli , Saccharomyces cerevisiae , Ratas Transgénicas , Antígeno HLA-B27 , Mucosa Intestinal/patología , Ratas Endogámicas F344 , Adhesión BacterianaRESUMEN
BACKGROUND: Primary immunodeficiencies (PIDs) in adults are mainly revealed by recurrent and/or severe bacterial infections. The objective of this study was to evaluate a systematic research strategy of PIDs in adults with unexplained bacterial infections, with a special focus on specific polysaccharide antibody deficiency (SPAD). METHODS: In this prospective multicenter study, inclusion criteria were recurrent benign upper and lower respiratory tract infections (RTIs) for at least two years (group 1), at least one upper or lower RTI requiring hospitalization (group 2), and/or at least one invasive infection documented with encapsulated bacteria (group 3). Main exclusion criteria were all local and general conditions that could explain infections. If no PID diagnosis was made, response to polysaccharide antigens was assessed using a pneumococcal polysaccharide vaccine. RESULTS: From March 2015 to March 2020, 118 patients were included (37 males, median age of 41 years): 73, 17, and 28 in groups 1, 2, and 3, respectively. Forty-seven PIDs were diagnosed, giving an estimated frequency of 39.8% (95% confidence interval [CI] [30.4, 48.8]). SPAD was the most frequent diagnosis by far (n = 37/47, 78.7%), and was made in 23, 5, and 9 patients from groups 1 to 3, respectively. All SPAD patients received conjugate vaccines and, according to their infectious history, were on surveillance or treated with preventive antibiotics (n = 6) and/or with immunoglobulins replacement therapy (n = 10), the latter being dramatically efficient in all cases. CONCLUSIONS: Considering its high prevalence among adults with unexplained recurrent and/or severe bacterial infections, SPAD should be screened in those patients. CLINICAL TRIALS REGISTRATION: NCT02972281.
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Infecciones Bacterianas , Síndromes de Inmunodeficiencia , Infecciones Neumocócicas , Enfermedades de Inmunodeficiencia Primaria , Masculino , Humanos , Adulto , Estudios Prospectivos , Síndromes de Inmunodeficiencia/complicaciones , Síndromes de Inmunodeficiencia/epidemiología , Síndromes de Inmunodeficiencia/diagnóstico , Polisacáridos , Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/tratamiento farmacológico , Enfermedades de Inmunodeficiencia Primaria/tratamiento farmacológico , Bacterias , Vacunas Neumococicas , Anticuerpos Antibacterianos , Infecciones Neumocócicas/prevención & controlRESUMEN
Microbial agents have promise for the bioremediation of Pb(II)-polluted environments and wastewater, the biodecontamination of foods, and the alleviation of toxicity in living organisms. The dairy bacterium Propionibacterium freudenreichii is poorly able to remove Pb(II) from aqueous solution at 25 ppm, ranging from 0 to 10% of initial concentration. Here, we report on an original strong enhancement of this activity (ranging from 75% to 93%, p < 0.01) following the addition of a polysorbate detergent (Tween® 80) during or either shortly after the growth of a P. freudenreichii culture. We evaluated the optimal Tween® 80 concentration for pretreatment conditions, documented the role of other detergents, and explored the possible mechanisms involved. Our results reveal a novel, environmentally friendly, low-cost pretreatment procedure for enhancing the selective removal of lead from water by probiotic-documented bacteria.
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Propionibacterium freudenreichii , Propionibacterium , Plomo , Polisorbatos , AguaRESUMEN
BACKGROUND AND AIMS: Adherent invasive Escherichia coli [AIEC] are recovered with a high frequency from the gut mucosa of Crohn's disease patients and are believed to contribute to the dysbiosis and pathogenesis of this inflammatory bowel disease. In this context, bacteriophage therapy has been proposed for specifically targeting AIEC in the human gut with no deleterious impact on the commensal microbiota. METHODS: The in vitro efficacy and specificity of a seven lytic phage cocktail [EcoActive™] was assessed against [i] 210 clinical AIEC strains, and [ii] 43 non-E. coli strains belonging to the top 12 most common bacterial genera typically associated with a healthy human microbiome. These data were supported by in vivo safety and efficacy assays conducted on healthy and AIEC-colonized mice, respectively. RESULTS: The EcoActive cocktail was effective in vitro against 95% of the AIEC strains and did not lyse any of the 43 non-E. coli commensal strains, in contrast to conventional antibiotics. Long-term administration of the EcoActive cocktail to healthy mice was safe and did not induce dysbiosis according to metagenomic data. Using a murine model of induced colitis of animals infected with the AIEC strain LF82, we found that a single administration of the cocktail failed to alleviate inflammatory symptoms, while mice receiving the cocktail twice a day for 15 days were protected from clinical and microscopical manifestations of inflammation. CONCLUSIONS: Collectively, the data support the approach of AIEC-targeted phage therapy as safe and effective treatment for reducing AIEC levels in the gut of IBD patients.
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Bacteriófagos , Colitis , Animales , Humanos , Ratones , Adhesión Bacteriana , Colitis/patología , Modelos Animales de Enfermedad , Disbiosis/complicaciones , Escherichia coli , Infecciones por Escherichia coli/complicaciones , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/patología , Mucosa Intestinal/patologíaRESUMEN
Abundance and diversity of bacteria and their viral predators, bacteriophages (phages), in the digestive tract are associated with human health. Particularly intriguing is the long-term coexistence of these two antagonistic populations. We performed genome-wide RNA sequencing on a human enteroaggregative Escherichia coli isolate to identify genes differentially expressed between in vitro conditions and in murine intestines. We experimentally demonstrated that four of these differentially expressed genes modified the interactions between E. coli and three virulent phages by either increasing or decreasing its susceptibility/resistance pattern and also by interfering with biofilm formation. Therefore, the regulation of bacterial genes expression during the colonization of the digestive tract influences the coexistence of phages and bacteria, highlighting the intricacy of tripartite relationships between phages, bacteria, and the animal host in intestinal homeostasis.
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Bacteriófagos , Animales , Bacterias/genética , Bacteriófagos/fisiología , Escherichia coli/genética , Expresión Génica , Genes Bacterianos , RatonesRESUMEN
INTRODUCTION: Osteoarticular infections (OAIs) of native joints lead to cartilage damage which may require subsequent arthroplasty. There is no consensus on systematic intraoperative microbiological sampling when performing an arthroplasty on a native joint with a history of OAI. We carried out a retrospective study to: (1) identify the frequency of the persistence of the microorganism(s) involved during the initial, presumed cured OAI, when performing an arthroplasty for sequelae of osteoarthritis, (2) to find an association between the length of time between the OAI and arthroplasty, and the recurrence of bacterial infection, (3) to assess the influence of the presence of hardware on the risk of infectious recurrence. HYPOTHESIS: Systematic sampling is justified during a subsequent arthroplasty after an OAI, even after a prolonged period. MATERIAL AND METHOD: This single-center, retrospective descriptive study included all patients whose indication for arthroplasty resulted from osteoarthritis, osteitis or bacterial osteomyelitis of a native joint, or in the aftermath of an infection post osteosynthesis. All patients were considered to have recovered from the initial infection at the time of the arthroplasty. Between 2008 and 2019, 92 patients were included in the study, with an average age of 56.5years (range: 21-97years). OAI occurred at a mean age of 35years (range: 1-84years). The average time from OAI to implantation was 15years (range: 1-65years). The bacteria most frequently found in the initial OAI was Staphylococcus aureus, involved in 35.8% of cases (n=33/92). RESULTS: The intraoperative samples came back positive in 17% of cases (n=16/92), including 9 positive for the same bacteria as the OAI (56%, n=9/16). For these 16 cases, the time between the OAI and the arthroplasty was 1year for 5 patients, between 1 and 15years for 5 patients and greater than 15years for 6 patients. For 3 positive patients, the information on the initial microorganism was not known and 4 patients were positive for a bacterium different from the initial one. The time from the initial OAI to the arthroplasty was not associated with positive results (p=0.38). There was no significant difference between a positive culture at the time of arthroplasty and the initial type of OAI [native joint versus presence of hardware and/or open fracture (p=0.41)]. CONCLUSION: The results of this work suggest there is value in microbiological sampling when performing an arthroplasty on a previously infected joint, regardless of the duration of the infection. LEVEL OF EVIDENCE: IV; retrospective study.
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Artritis Infecciosa , Osteoartritis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Artritis Infecciosa/microbiología , Artritis Infecciosa/cirugía , Artroplastia , Niño , Preescolar , Humanos , Lactante , Extremidad Inferior , Persona de Mediana Edad , Osteoartritis/complicaciones , Osteoartritis/cirugía , Estudios Retrospectivos , Adulto JovenRESUMEN
The adherent-invasive Escherichia coli (AIEC) pathotype has been implicated in the pathogenesis of inflammatory bowel diseases in general and in Crohn's disease (CD) in particular. AIEC strains are primarily characterized by their ability to adhere to and invade intestinal epithelial cells. However, the genetic and phenotypic features of AIEC isolates vary greatly as a function of the strain's clonality, host factors, and the gut microenvironment. It is thus essential to identify the determinants of AIEC pathogenicity and understand their role in intestinal epithelial barrier dysfunction and inflammation. We reasoned that soil nematode Caenorhabditis elegans (a simple but powerful model of host-bacterium interactions) could be used to study the virulence of AIEC vs. non- AIEC E. coli strains. Indeed, we found that the colonization of C. elegans (strain N2) by E. coli impacted survival in a strain-specific manner. Moreover, the AIEC strains' ability to invade cells in vitro was linked to the median lifespan in C. elegans (strain PX627). However, neither the E. coli intrinsic invasiveness (i.e., the fact for an individual strain to be characterized as invasive or not) nor AIEC's virulence levels (i.e., the intensity of invasion, established in % from the infectious inoculum) in intestinal epithelial cells was correlated with C. elegans' lifespan in the killing assay. Nevertheless, AIEC longevity of C. elegans might be a relevant model for screening anti-adhesion drugs and anti-invasive probiotics.
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BACKGROUND: The optimal length of the intravenous antibiotic treatment of periprosthetic joint infections (PJIs) generally ranges from one to six weeks and is a matter of debate. Most antibiotics active against Gram-positive cocci (GPC) exhibit both high oral bioavailability and bone diffusion. Thus, early oral therapy may be a reasonable option in GPC-related PJIs. METHODS: A 2 year before and after monocentric study that aimed to compare two antibiotic strategies. Empirical intravenous postoperative antibiotic treatment was followed by 7 to 10 days of intravenous targeted therapy ('before' group) or by full orally targeted antibiotic treatment ('after' group). The primary outcome was a treatment failure during follow-up. RESULTS: A total of 93 patients were analysed, 43 and 50 in the before and the after groups, respectively. Both groups were comparable in terms of surgical procedures, comorbidities, microbiological documentation and infection site. Antibiotics prescribed to our patients had high oral bioavailability and bone diffusion with rifampicin/fluoroquinolone combinations being the most frequent antibiotic regimens. Both hospital stay and intravenous antibiotic treatment mean durations were shorter in the before group than in the after group [15.0 versus 11.0 days; (Pâ<â0.01) and 13.0 versus 7.0 days; Pâ<â0.001, respectively]. The remission rate assessed after at least a year of follow-up was comparable in the before and the after groups (hazard ratioâ=â0.70; 95% CI 0.30-1.58). CONCLUSIONS: Full oral targeted antibiotic therapy using a drug regimen with high oral bioavailability and good bone diffusion is an option for the treatment of patients with GPC-related PJIs.
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Cocos Grampositivos , Administración Intravenosa , Administración Oral , Antibacterianos/uso terapéutico , Humanos , RifampinRESUMEN
The genus Staphylococcus is the main causative agent of bone and joint infections (BJI) in which outcomes are impacted by both effective surgical and appropriate antimicrobial management. In this context, methicillin resistance (MR) detection is a microbiological challenge to optimize the anti-staphylococcal drug coverage and to secure the surgical procedure. During the last decade, molecular tools have been developed to rapidly detect bacterial-resistant strains in clinical samples. The GeneXpert MRSA/SA SSTI® assay (Cepheid, Sunnyvale, CA, USA) is a real-time PCR method aimed at detecting methicillin-resistant Staphylococcus aureus (MRSA) in skin and soft tissues infections. In the literature, this test has been reported to be diverted from its original purpose to be evaluated in surgical samples. Within the current review, we update the GeneXpert MRSA/SA SSTI® assay performance in staphylococcal species determination (i.e., S. aureus vs. coagulase-negative species) together with MR genotype detection, when performed in osteoarticular infections.
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Toxic metals (such as lead, cadmium, and, to a lesser extent, aluminum) are detrimental to health when ingested in food or water or when inhaled. By interacting with heavy metals, gut and food-derived microbes can actively and/or passively modulate (by adsorption and/or sequestration) the bioavailability of these toxins inside the gut. This "intestinal bioremediation" involves the selection of safe microbes specifically able to immobilize metals. We used inductively coupled plasma mass spectrometry to investigate the in vitro ability of 225 bacteria to remove the potentially harmful trace elements lead, cadmium, and aluminum. Interspecies and intraspecies comparisons were performed among the Firmicutes (mostly lactic acid bacteria, including Lactobacillus spp., with some Lactococcus, Pediococcus, and Carnobacterium representatives), Actinobacteria, and Proteobacteria. The removal of a mixture of lead and cadmium was also investigated. Although the objective of the study was not to elucidate the mechanisms of heavy metal removal for each strain and each metal, we nevertheless identified promising candidate bacteria as probiotics for the intestinal bioremediation of Pb(II) and Cd(II).
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A recently developed, automated blood culture system and medium improve the time-to-positivity (TTP) for bacteremia. However, there have thus far been no genus-level analyses using this novel system. We evaluated and compared the changes in blood culture TTP between two systems: BacT/Alert 3D with a blood culture medium containing activated charcoal versus the more recent BacT/Alert Virtuo with a blood culture medium containing polymeric beads. This before-and-after study included blood cultures collected between July 2010 and April 2014 (3D, activated charcoal) and between July 2015 and April 2018 (Virtuo, polymeric beads). A total of 554,732 blood cultures were included, 267,935 (48.30%) during the first period and 286,797 (51.70%) during the second period. Overall, 55,611 (10.02%) tested positive for at least one microorganism. The incubation of the blood culture medium in the Virtuo system was associated with reduced TTP for the most prevalent bacteria, those representing 91.72% (n=51,006) of all the positive blood cultures. The median TTP was reduced by 0.99 h for Staphylococcus, Enterococcus, Streptococcus, Pseudomonadales, and most of the genera within the order Enterobacterales (except the family Morganellaceae). However, strictly anaerobic bacteria belonging to the genus Bacteroides, representing 0.85% (n=474) of all positive blood cultures, were detected 4.53 h later using the Virtuo system. Virtuo was associated with a shorter TTP for most bacteria, but this improvement was heterogeneous to the genus level.
Asunto(s)
Bacteriemia/diagnóstico , Cultivo de Sangre/métodos , Automatización , Bacterias/clasificación , Bacterias/aislamiento & purificación , Técnicas Bacteriológicas , Carbón Orgánico , Medios de Cultivo , Humanos , Microesferas , Factores de TiempoRESUMEN
Clostridium spp. are recovered from 25% of the blood culture positive with anaerobes. However, the clinical relevance of Clostridium bacteremia has been controverted in the literature, particularly for C. perfringens. We aimed to evaluate the clinical relevance of Clostridium bacteremia, either due to C. perfringens or other Clostridium species, and to identify the risk factors of mortality in these patients. A retrospective cohort study was conducted from January 2010 to April 2018. All the patients with at least one blood culture positive with any Clostridium species were included. Eighty-one patients with a least one blood culture positive with any Clostridium species were included. Seventy patients (86.4%) fulfilled the criteria for clinically relevant bacteremia. Bacteremia due to C. perfringens tended to be less clinically relevant than other Clostridium species but this was not statistically significant (76% vs 91.2%, Pâ¯=â¯0.09). In case of clinically relevant bacteremia, the 30-day mortality rate was 31.4%. In multivariate analysis, adequate empiric antimicrobial therapy was significantly associated with survival (Pâ¯=â¯0.03). In conclusion, bacteremia due to C. perfringens or other Clostridium species is usually clinically relevant. This finding was also supported by an improved survival at 30 days when adequate empiric antimicrobial therapy was administered.