Penicillin G Research Articles

Effects of therapeutic levels of dietary antibiotics on the cecal microbiome composition of broiler chickens

Dietary antibiotics, including antibiotic growth promoters (AGPs), have been commonly used to improve health and growth of poultry. The present study investigated the effects of therapeutic doses of dietary antibiotics, including bacitracin methylene disalicylate (BMD), penicillin G potassium (PP) and an ionophore (salinomycin, SA), on the cecal microbiome of chickens. BMD and SA treatments were given as dietary supplements from d 1 to 35 of age. The SAPP (salinomycin+ penicillin G potassium) group was given SA as a dietary supplement from d 1 to 35 of age and PP was added to drinking water from d 19 to 24 of age to simulate common practices for control of necrotic enteritis in broilers. The cecal contents were collected from all treatment groups on d 10, 24, and 35 of age and DNA was extracted for metagenomic analysis of the cecal microbiome. The results revealed that dietary or water supplementation of therapeutic levels of antibiotics and ionophores to chickens significantly altered the cecal microbial homeostasis during different stages of the chicken life. The alpha diversity analysis showed that BMD, SA, and SAPP treatments decreased diversity and evenness of the cecal microbiome of treated chickens on d 10 of age. Species richness was also reduced on d 35 following treatment with BMD. Beta diversity analyses revealed that SAPP and BMD induced significant changes in the relative abundance of Gram-positive and -negative bacteria on d 10, while no significant differences were observed on d 24. On d 35, the non-treated control group had higher relative abundance of unclassified Gram-positive and -negative bacteria compared to SA, SAPP, and BMD treatment groups. Overall, despite their beneficial role in controlling necrotic enteritis outbreaks, the findings of this study highlight the potential negative effects of dietary supplementation of therapeutic levels of antibiotics on the gut microbiome and suggest that adjusting gut bacteria may be required to restore microbial richness and diversity of the gut microbiome following treatment with these antibiotics.

Detection Of Serum Specific IgE By Fluoro-Enzyme Immunoassay For The Diagnosis Of Immediate Allergic Reactions To Penicillins

Diagnosis of IgE-mediated allergic reactions to penicillins is based on the clinical history, skin tests (STs), and drug provocation tests (DPTs). Among in vitro complementary tests, the fluoro-enzyme immunoassay (FEIA) ImmunoCAP® (Thermo-Fisher) is the most widely used commercial method for detecting drug specific IgE (sIgE). The aim of this study is to analyze ImmunoCAP® usefulness for detecting sIgE to penicillin G (PG) and amoxicillin (AX), in patients with confirmed penicillin allergy.

Multiclass and multi-residue screening of mycotoxins, pharmacologically active substances, and pesticides in infant milk formulas through ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry analysis

Infant milk formulas are designed to substitute human milk when breastfeeding is unavailable. In addition to human milk and milk-derived products, these formulas can be a vehicle of contaminants. In this work, a multiclass method based on the QuEChERS (quick, easy, cheap, effective, rugged, and safe) approach was developed for the simultaneous determination of contaminants (n = 45), including mycotoxins and veterinary drug residues, occurring in infant milk formulas. By using an ultra-high-performance liquid chromatography quadrupole-Orbitrap coupled with high-resolution mass spectrometry analysis (UHPLC-Q-Orbitrap HRMS; Thermo Fisher Scientific), further retrospective analysis of 337 contaminants, including pesticides, was achieved. The method was validated in accordance with European regulations and applied for the analysis of 54 infant milk samples. Risk assessment was also performed. Dexamethasone was detected in 16.6% of samples (range: 0.905-1.131 ng/mL), and procaine benzyl penicillin in 1 sample at a concentration of 0.295 ng/mL. Zearalenone was found in 55.5% of samples (range: 0.133-0.638 ng/mL) and α-zearalenol in 16.6% of samples (range: 1.534-10.408 ng/mL). Up to 49 pesticides, 11 veterinary drug residues, and 5 mycotoxins were tentatively identified via retrospective analysis based on the mass spectral library. These findings highlight the necessity of careful evaluation of contaminants in infant formulas, considering that they are intended for a vulnerable part of the population.

Synthesis of Novel 6-(chloromethyl) - N2- (1 - (4-substituted phenyl) - 3-phenyl - 1H-pyrazol - 4-yl) methylene)-N4- aryl-1, 3, 5-triazine - 2, 4-diamine derivatives and their Antimicrobial Activity

A series of 6-(chloromethyl)-N2-(1-(4-substituted phenyl)-3-phenyl-1H-pyrazol-4-yl) methylene)-N4-aryl-1, 3, 5-triazine - 2, 4-diamine 7(Aa-Gd) were synthesized using the appropriate synthetic procedure and characterized by spectral analysis. All the synthesized compounds were evaluated for their antibacterial and antifungal activities. The antibacterial activity was evaluated against Gram-positive strains (Staphylococcus aureus, Streptococcus aureus) and Gram-negative strains (Escherichia coli, Pseudomonas aeruginosa) using benzyl penicillin and streptomycin as standard drugs. Further, these compounds were studied for antifungal activity against three strains of fungi (Candida albicans, Aspergillus fumigate and Aspergillus flavus) using Ketoconazole as a standard drug. In the presented study all the synthesized compounds showed significant antibacterial and antifungal activities.

ИЗМЕНЕНИЕ КРИСТАЛЛИЧЕСКОГО СТРОЕНИЯ ПОРОШКООБРАЗНОГО БЕНЗИЛПЕНИЦИЛЛИНА НАТРИЕВОЙ СОЛИ ПОД ВОЗДЕЙСТВИЕМ ИМПУЛЬСНОГО МАГНИТНОГО ПОЛЯ ВЫСОКОЙ НАПРЯЖЕННОСТИ

To understand the nature of the influence of a pulsed magnetic field on the antibacterial properties of benzylpenicillin sodium salt against Escherichia coli M-17 bacteria, an exploratory study of benzylpenicillin sodium salt powder under X-ray radiation was performed. Corresponding diffraction patterns were obtained, reflecting the changes occurring in the antibiotic molecule after the impact of a PMF on the drug. The fact of disorganization of the crystal lattice of powdered benzylpenicillin under the influence of a pulsed magnetic field with a strength of (2÷7) 106 A/m has been established.

Impact of antibiotics on spermatozoa quality and bacterial load of chilled-stored camels (Camelus dromedarius) semen.

This experiment was conducted to assess the effect of different antibiotics in tris-fructose egg yolk-based diluent on bacterial load and sperm quality of dromedary camels during processing and cold storage. Ten semen ejaculates were collected from five male dromedary camels. Each sample was fractioned into four equally divided aliquots and diluted in one of four tris-fructose egg yolk. The first extender contained no antibiotic (NC). The second extender included streptomycin sulphate (1000 μg/ml) and benzyl penicillin (1000 IU/ml) (SP). The third extender was supplied with 250 μg/ml gentamicin sulphate (Gent). The fourth extender contained 500 μg/ml gentamicin sulphate,100 μg/ml tylosin tartrate, 300 μg/ml lincomycin hydrochloride and 600 μg/ml spectinomycin hydrochloride (GTLS). After dilution, the extended semen samples were cooled to 5 °C within 2 h and finally stored at 5 °C for 72 h. Microbial concentration, motility of spermatozoa, live spermatozoa, plasma membrane and acrosome integrity percentages were evaluated just after dilution at 35 °C, 0, 24, 48 and 72 h from the start of cooling to 5 °C. The results revealed that the diluent containing gentamicin had significantly (P<0.05) maximum motility percentage at the different examination intervals. The pattern of live spermatozoa percentage was varied between the different treatments at different examination intervals. The diluent supplied with Gent was distinguished with a significant peak percentage (P<0.05) of swelled spermatozoa among the other antibiotics supplied diluents. The number of colony-forming units isolated from the semen samples kept in diluent containing no antibiotics was significantly (P<0.05) higher than that isolated from the diluents supplemented with antibiotics. In conclusion, the semen diluents fortified with gentamicin generally keep the motility, acrosomal and plasma membrane integrity and live spermatozoa for 72-h preservation of dromedary semen.

Synthesis and Antibacterial Activity of Hydroxy and Chloro-Substituted Chalcone Derivatives

Chalcones are a class of natural products reported with a wide range of biological activities. Among them antibacterial is much promising and many potent chalcones have been emerged as useful antibacterial agents. In view of this, we synthesized 15 chalcones (3a-3o) containing both hydroxyl and chlorine substituents and studied them by using spectroscopic methods. The compounds were tested for antibacterial efficacy against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Proteus vulgaris, among other harmful microorganisms. The compounds have moderate to high antibacterial activity, among them heteroaromatic ring containing compounds (3m, 3n, and 3o) elicited higher activity than the standard drug benzyl penicillin. The compound 3m having the pyridinyl compound displayed the maximum activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Proteus vulgaris, with zone of inhibition (in mm) values of 27.52±0.16, 28.85±0.11, 22.05±0.16, and 23.18±0.17, respectively. The synthesized compounds could be used as lead molecules in the development of novel antibacterial medicines.

Selective Detection of Penicillin G Antibiotic in Milk by Molecularly Imprinted Polymer-Based Plasmonic SPR Sensor.

Molecularly imprinted polymer-based surface plasmon resonance sensor prepared using silver nanoparticles was designed for the selective recognition of Penicillin G (PEN-G) antibiotic from both aqueous solution and milk sample. PEN-G imprinted sensors (NpMIPs) SPR sensor was fabricated using poly (2-hydroxyethyl methacrylate-N-methacroyl-(L)-cysteine methyl ester)-silver nanoparticles-N-methacryloyl-L-phenylalanine methyl ester polymer by embedding silver nanoparticles (AgNPs) into the polymeric film structure. In addition, a non-imprinted (NpNIPs) SPR sensor was prepared by utilizing the same polymerization recipe without addition of the PEN-G template molecule to evaluate the imprinting effect. FTIR-ATR spectrophotometer, ellipsometer, contact angle measurements were used for the characterization of NpMIPs SPR sensors. The linear concentration range of 0.01–10 ng/mL PEN-G was studied for kinetic analyses. The augmenting effect of AgNPs used to increase the surface plasmon resonance signal response was examined using polymer-based PEN-G imprinted (MIPs) sensor without the addition of AgNPs. The antibiotic amount present in milk chosen as a real sample was measured by spiking PEN-G into the milk. According to the Scatchard, Langmuir, Freundlich and Langmuir–Freundlich adsorption models, the interaction mechanism was estimated to be compatible with the Langmuir model.

English

Platform tests are usually simple and rapid quality control tests which serve as a basis for accepting, setting aside or rejecting raw milk. Some of the rapid antibiotic residues test kits available in the Kenyan market include: Delvo test Fast BL, Delvo Sulphadiazine Penicillin No Tablet (SPNT), Mtusbio Beta-lactam BLQ Rapid Test Kit and Ringbio beta-lactam, tetracycline, sulfa drugs, BTS 3 in 1 TriTest S. Ndungu Antibiotic residues (NAR) is a colour comparison test that is simple, rapid and does not require electric power in its analysis procedure. This study compared these four rapid antibiotics tests with novel NAR test method in terms of sensitivity and specificity. A total of 28 samples were prepared; 8 milk samples without residues were spiked with milk known to have beta-lactam residues while 10 had no residues and 10 had known beta-lactam (benzyl penicillin) residues. The four analysis methods were carried out as described in their technical bulletins and manuals. For the NAR test, 50 mg of its active ingredient was mixed with 3 ml of milk and colour change observations made. The sensitivity and specificity of the NAR test was found to be 66.7 and 100% respectively while for all the other four tests, sensitivity and specificity was established to be 100% for each. The Kappa coefficient was 0.5882 which indicates moderate agreement, between NAR test method and the other test methods, according to Landis-Koch scale. The odds ratio exhibited positive association between the NAR test and the four methods. NAR test is best applicable at the milk collection routes or farm level before bulking for transportation. &nbsp; Key words: Antibiotic residues, rapid test kit, beta-lactam, beta-lactamase, NAR test.

Penicillins' Solubility in Supercritical Carbon Dioxide: Modeling by Cubic Equations of States Revisited.

Development of processes using green solvents as supercritical fluids (SCFs) depends on the accuracy of modeling and predicting phase equilibrium which is of considerable importance to exploit the use of SCF process at the level of pharmaceutical industries. Solid-Fluid equilibrium modeling is associated to many drawbacks when compressed gas-based models as cubic equations of states (cEoSs) are used. The unavailability of experimental values of solute’s sublimation pressure presents one of the major obstacles to the solubility modeling with this type of models, and thus, its estimation is essential and inevitable. This work is an attempt to address a question regarding “accurate estimated value” of sublimation pressure of two antibiotics Penicillin G (benzyl penicillin) and Penicillin V (phenoxymethyl penicillin). Toward that, first, cEoSs are provided as the thermodynamics modeling framework and fundamental approach. Second, a discussion and a review of some literature results are given. Third, results are invoked to present a criticism analysis that comes from the use of modified form of Peng-Robinson (PR) equation of states. Finally, considerable improvement of modeling results by using a new sublimation pressure is shown.

Evaluation of developmental toxicity of ammonium dinitramide by micromass culture and embryonic stem cells models

Objective: To evaluated the potential developmental toxicity and teratogenicity of ammonium dinitroamide (ADN) by micromass test (MM Test) and embryonic stem cell test models. Methods: In September 2018, rat embryos were isolated and limb bud cells were collected. The limb bud cells were treated with different concentrations of ADN (0, 312.50, 625.00, 1250.00, 2500.00, 5000.00, 10000.00 μg/ml) . Half proliferation inhibitory concentration and half differentiation inhibitory concentration were calculated and the teratogenic effects were evaluated according to the criteria. For the embryonic stem cell test, the effects of different concentrations of ADN (0, 39.06, 78.13, 156.25, 312.50, 625.00, 1250.00, 2500.00 μg/ml) on the differentiation of mouse embryonic stem cells (mESCs) into myocardial cells and the cytotoxicity of mESCs and 3T3 cells were detected. The embryonic toxicity was evaluated according to the criteria. In this study, both 5-fluorouracil (5-FU) , a known strong embryonic toxic drug, and penicillin-G (P-G) , a non-embryonic toxic drug, were used to verify the effectiveness of the model, and the validated test model was applied to evaluate the embryonic toxicity of ADN. Results: In the MM Test, the inhibition rates of proliferation and differentiation of limb bud cells in ADN groups were higher than that in control group (P<0.05) . And the half proliferation inhibitory concentration and half differentiation inhibitory concentration of ADN on limb bud cells were 7480.32 and 4526.09 μg/ml, respectively. ADN was determined to be non-teratogenic by standard. In the embryonic stem cell test, the inhibition rates of mESCs proliferation in ADN groups were higher than that in control group, and the inhibition rates of 3T3 cells in 156.25, 312.50, 625.00, 1250.00, 2500.00 μg/ml ADN groups were higher than that in control group (P<0.05) . The half proliferation inhibitory concentration and half differentiation inhibitory concentration of ADN on mESCs were 1851.73 and 1796.39 μg/ml, respectively, and the half proliferation inhibitory concentration on 3T3 cells was 3334.35 μg/ml. ADN was determined to be non-embryotoxic by standard. Conclusion: After evaluation by MM Test and embryonic stem cell models, ADN has no embryo toxicity and is a non-teratogenic substance.

Intraspecific and interspecific quorum sensing of bacterial community affects the fate of antibiotic resistance genes during chicken manure composting under penicillin G stress

In this study, the effects of penicillin G (PENG) on the fate of bacterial communities and β-lactamase antibiotic resistance genes (ARGs) during chicken manure composting were assessed, to illustrate the roles of PENG in ARGs behavior. The results showed that the total absolute abundances of 9 ARGs and 4 mobile genetic elements (MGEs) was significantly increased by PENG (P < 0.05). Dozens of potential hosts for ARGs were predominantly affiliated with Firmicutes, Proteobacteria, and Actinobacteria. Meanwhile, the higher concentration of PENG significantly increased the abundance of luxI and luxS in quorum sensing (QS) (P < 0.05), which enhanced the frequency of inter/intraspecific gene “communication.” Redundancy analysis and structural equation modeling further revealed that QS had a strong regulatory role in horizontal gene transfer of ARGs mediated via MGEs. These results provide new insight into the mechanism of ARGs propagation in aerobic composting modified by PENG.

MRSA REMAINS A GREAT PRIORITY DUE TO THE TREMENDOUS MORTALITY --- A BIRD'S EYE VIEW

Methicillin-resistant Staphylococcus aureus (MRSA) is difcult to treat with methicillin, amoxicillin, penicillin, oxacillin, and other commonly used antibiotics because of its resistance. Staphylococcus organisms rapidly develop drug resistance as many as 50% of the domiciliary and 80% of the hospital strains are now penicillin resistant. Staphylococcus aureus also show multiple drug resistance. Therefore, Staphylococcal isolates should always be tested for antimicrobial sensitivity and chronic infection should be treated by more than one drug. Before 1960,when methicillin, is the rst penicillin's-resistant penicillin's, was brought into use, about 1%of the strains of the Staphylococcus aureus were "methicillin resistant" and by 1970 in Britain their proportion has risen to about 5%.These strains are tolerant of, low therapeutic concentrations of methicillin, cloxacillin, benzyl penicillin and ampicillin.They do not destroy methicillin and cloxacillin, but most of them are penicillinase-producing as well as being "methicillin resistant" and therefore inactivate benzyl penicillin and ampicillin. Its resistance is uncertain since infections may be cured with a high dose of methicillin.

Degradation performance and mechanism of penicillin G in aqueous solution by ionizing radiation

Penicillin G (PG), a frequently detected β-lactam antibiotic in aquatic environment, has attracted extensive concerns because of its extensive application and potential to develop antimicrobial resistance. In this study, gamma radiation was used to degrade PG in water. The main influencing factors, such as initial PG concentration, pH value, absorbed dose, as well as water matrix (inorganic anions and organic matters) were investigated. Results showed that lower initial concentration, acidic condition (pH = 5.57), and higher absorbed dose was conducive to PG degradation. Besides, NO3−, HCO32−, SO42− and HPO42− had negative influence on PG degradation, while Cl− had positive influence. Organic matters had negative influence. Twelve transformation intermediate products (TPs) were identified during PG degradation. Together with the density functional theory (DFT) calculation, four possible pathways of PG degradation were proposed. The results of antibacterial activity test demonstrated that the transformation of PG to TPs eliminated the antibacterial activity. Notably, except some para-modified products of PG, the toxicity of other TPs was reduced PG degradation. Moreover, no potential risk of bacterial mutagenicity during PG degradation was observed. In summary, ionizing radiation has good performance in PG degradation in the real wastewater.

Mushroom ( Amanita phalloides) Poisoning: Mechanisms, Pathogenesis, Prognosis and Strategies of Treatment

Poisoning due to mushroom consumption is uncommon, but it causes death by causing acute liver failure (ALF). The ingestion of Amanita phalloides, is one of the ultimate frequent causes of mushroom poisoning globally. This type has three main categories of toxins: amatoxins, phallotoxins, and virotoxins. From these toxins amatoxins and its metabolite α-amanitin, is the main cause of toxicity in population which cause deterioration in synthesis of protein and consequent cell necrosis and inhibition of RNA polymerase II ,so finally cause cell death. Liver is the chief organ involved in toxicity, kidneys and central nervous system also involved. Latent period has been proceeds the poisoning symptoms, which includes gastrointestinal symptoms followed by liver failure symptoms, coma and ultimately death. Management including supportive cares, gastrointestinal decontamination, special medications (Benzyl penicillin, N-acetyl cyctien, cimetidine, silibinin and others) and, finally liver transplantation if clinical condition deteriorated.&#x0D;

Clinical Profile and Outcome of Group B Streptococcal Colonization in Mothers and Neonates in Ras Al Khaimah, United Arab Emirates: A Prospective Observational Study.

Background:Maternal Group B Streptococcus (GBS)/Streptococcus agalactiae colonization rates vary worldwide; however, no such recent data are available from the United Arab Emirates (UAE).Objective:The objective of this study was to determine the prevalence of GBS colonization among pregnant women attending an antenatal clinic of a hospital in Ras Al Khaimah, UAE, along with the antibiotic sensitivity pattern, the clinical profile and pregnancy (maternal and fetal) outcome.Methods:This prospective observational study routinely offered rectovaginal swab for GBS to all women attending the antenatal clinic at 35–37 weeks of pregnancy between January and December 2019. MASTASTREP kit and Vitek-2 identification system was used for culture and identification. Women with positive cultures were followed up for any maternal and neonatal complications and the use of intrapartum antibiotic prophylaxis (IAP).Results:A total of 2295 women were included, of which 158 (6.9%) had positive cultures for GBS colonization. The carriage rate was higher in women without any risk factors for early-onset GBS disease (EOGBS) (P < 0.01). The GBS isolates were about 97% susceptible to linezolid and vancomycin, 90% to benzyl penicillin and 95% to ampicillin. Resistance to trimethoprim/sulfamethoxazole, clindamycin, erythromycin, and levofloxacin were about 77%, 57%, 57%, and 10%, respectively. Urinary tract infection in GBS colonized women were more common in those aged ≤30 years (P = 0.009). Fetal outcome was favorable in women receiving IAP for GBS colonization. No neonate had culture proven EOGBS.Conclusion:The prevalence of GBS colonization in pregnant women as well as the overall maternal and neonatal complications is low in Ras Al Khaimah, UAE. IAP is effective in preventing early-onset sepsis in newborn, and thus should be initiated in those with GBS colonization. The cultured GBS showed sensitivity to most antibiotics.

Detection of benzylpenicillin sodium and ampicillin residue based on flower-like silver nanostructures using surface-enhanced Raman spectroscopy

Detection of benzylpenicillin sodium and ampicillin residue based on flower-like silver nanostructures using surface-enhanced Raman spectroscopy

Preparation of gold core and silver shell substrate with inositol hexaphosphate inner gap for Raman detection of trace Penicillin G

The abuse of Penicillin G (PG) in the feeds of livestock resulted in health risk for human being via the food chain. It is urged to develop the rapid and sensitive method for monitoring PG residue in food products. In this work, silver shell was formed on the core gold nanoparticles protected with inositol hexaphosphate (IP6), designated as Ag@IP6@AuNPs, which is used as surface enhanced Raman scattering (SERS) substrate. Thanks to the presence of IP6 between silver shell and core gold, Ag@IP6@AuNPs show high storage stability. The great surface plasmon resonance of hot spot field generated in the molecular gap between core-shell extends to nanoparticle surface results in synergistic enhancement of Raman scattering effect. Ag@IP6@AuNPs-based SERS assay is employed to successfully detect trace PG residue in milk with a wide linear quantitative range from 10−5 to 10-11 mol/L and the limit of detection at 10-12 mol/L. The sensitivity of such Raman protocol meets the requirement for the maximum residue limit (MRL, 4 μg/kg or 1.2 × 10−8 mol/L) of PG in milk products set by the European Union. Additionally, the detection recoveries in the range from 92.18 % to 101.4 % mean the acceptable robustness of such SERS method. The proposed SERS method could be advanced to realize the on-field determination of PG in milk for guarantee of food safety.

Photocatalytic degradation of Penicillin G in aqueous solutions: Kinetic, degradation pathway, and microbioassays assessment

The photocatalytic degradation of pharmaceutical micropollutants of Penicillin G (PG) was investigated in a photoreactor at a laboratory scale. The impact of type of catalyst, pH, and initial concentration of PG were studied. Maximum removal efficiency was obtained at pH = 6.8, [ZnO]0 = 0.8 g L−1, and [PG]0 = 5 mg L−1 and reaction time of 150 min. The addition of persulfate sodium (PPS) enhanced the efficiency of the photocatalytic reaction. The efficiency of photolysis process in the presence of PPS was significantly improved to 72.72% compared to the classical photocatalysis system (56.71%). Optimum concentration of PPS to completely degraded PG was found to be 500 mg L−1. The QuEChERS extraction, GC-MS/MS method, and concentration technique showed favorable performance identification of the possible mechanism of PG degradation pathway. Toxicity of PG and its by-products were evaluated using microbioassays assessment based on nine selected bacterial strains. Results confirmed the effectiveness of the implemented system and its safe use via the bacteria Bacillus subtilis, which has illustrated significant activity. Due to the high efficiency, facility benefits, and low-cost of the suggested process, the process can be considered for the degradation of various pharmaceutical contaminants in pharmaceutical industry treatment under the optimal conditions.

A rare case of periprosthetic Trueperella bernardiae following a total hip arthroplasty and antimicrobial stewardship

Trueperella bernardiae is a rare, anaerobic Gram-positive bacillus. Very few published clinical reports1 of Trueperella infections, eludes its true incidence and pathogenicity. We share a case of a 70-year-old woman with recurrent peri-prosthetic joint infection (PJI) following a total hip arthroplasty. A month after hip replacement, she presented with PJI, which was treated with extensive debridement and oral Ciprofloxacin in community for ESBL Enterobacteriaceae from peri-prosthetic samples. Five months later, she represented with peri-prosthetic collection which grew Trueperella bernardiae, during stage 1 hip revision. This was treated in hospital with six-weeks intravenous (IV) benzyl penicillin. A month after the second stage revision, she presents with hip re-collection that grew ciprofloxacin resistant Escherichia coli. She was managed in community with a 6-week IV carbapenem. However, 12 months later she developed a psoas abscess and subsequently elected for cessation of active management, leading to her demise. This report emphasises on the emergence of antimicrobial resistance2 Enterobacteriaceae due to constant antibiotic pressure, possibly causing a prosthetic joint infection by a rare Trueperella bernardiae, which was treated effectively by a narrow spectrum penicillin. This case report calls the need for antimicrobial stewardship3 while elucidating the existence of rare pathogens. 1.Loïez C, Tavani F, Wallet F, et al. An unusual case of prosthetic joint infection due to Arcanobacterium bernardiae. J Med Microbiol 2009; 58: 842–3.2.Serwecińska L. Antimicrobials and antibiotic-resistant bacteria: a risk to the environment and to public health. Water 2020; 12: 3313.3.McKenzie D, Rawlins M, Del Mar C. Antimicrobial stewardship: what’s it all about? Aust Prescr 2013; 36: 116–20.