Photodynamic black phosphorus nanosheets functionalized with polymyxin B for targeted ablation of drug-resistant mixed-species biofilms.

Biofilms, particularly those formed by multiple bacterial species, pose significant economic and environmental challenges, especially in the context of medical implants. Addressing the urgent need for effective treatment strategies that do not exacerbate drug resistance, we developed a novel nanoformulation, Ce6&PMb@BPN, based on black phosphorus nanosheets (BPN) for targeted treatment of mixed-species biofilms formed by Acinetobacter baumannii (A. baumannii) and methicillin-resistant Staphylococcus aureus (MRSA).The formulation leverages polymyxin B (PMb) for bacterial targeting and chlorin e6 (Ce6) for photodynamic action. Upon near-infrared (NIR) irradiation, Ce6&PMb@BPN efficiently eliminates biofilms by combining chemotherapy, photodynamic therapy (PDT) and photothermal therapy (PTT), reducing biofilm biomass significantly within 30 min. In vivo studies on mice infected with mixed-species biofilm-coated catheters demonstrated the formulation's potent antibacterial and biofilm ablation effects. Moreover, comprehensive biosafety evaluations confirmed the excellent biocompatibility of Ce6&PMb@BPN. Taken together, this intelligently designed nanoformulation holds potential for effectively treating biofilm-associated infections, addressing the urgent need for strategies to combat antibiotic-resistant biofilms, particularly mixed-species biofilm, in medical settings.

Evaluation and management of febrile neutropenia in patients with cancer.

ABSTRACT: Febrile neutropenia is a common oncologic emergency that increases the risk for serious infection. This article reviews a joint American Society of Clinical Oncology and Infectious Diseases Society of America guideline for the evaluation and management of patients with cancer who present with fever and neutropenia. Knowledge and use of available risk assessment tools may reduce unnecessary hospitalizations, decrease inappropriate antibiotic use, and improve patient outcomes.

Enhancing Sepsis Outcomes: A 7-Year Multidisciplinary Endeavor.

Regulatory bodies in the United States have implemented quality metrics aimed at improving outcomes for patients with severe sepsis and septic shock. The current study was a quality improvement (QI) project in a community-based academic center aimed at improving adherence to sepsis quality metrics, time to antibiotic administration, and patient outcomes. Electronic health record systems were utilized to capture sepsis-related data. Regular audits and feedback sessions were conducted to identify areas for improvement, with a focus on the timely administration of antibiotics. Interventions included improving access to antibiotics, transitioning from intravenous piggyback to intravenous push formulations, and providing continuous staff education and training. This multidisciplinary QI initiative led to significant improvements in the mortality index, length of stay index, and direct cost index for patients with sepsis. Targeted multidisciplinary QI interventions resulted in improved quality metrics and patient outcomes.

Effect of Cymbopogon olivieri-based herbal vaginal product on bacterial vaginosis.

OBJECTIVE: Bacterial vaginosis is the most common vaginal infection in reproductive-age women. If it is not treated, the quality of life will be reduced. In this study, the herbal medicine product Cymbopogon olivieri was used for its treatment. METHODS: This study was conducted with 90 women. The patients were randomly divided into two groups of 45: Cymbopogon olivieri and metronidazole. The treatment period was 7 days for each group. Improvement status was determined by eliminating at least three out of four of Amsel's criteria. A new variable with two order levels (negative and positive) was constructed. This new variable shows the status of the treatment process. Chi-square and Fisher's exact tests were used to examine the relationship between the new variable and treatment status. RESULTS: The results demonstrate that Cymbopogon olivieri and metronidazole significantly reduced the burning, itching, malodor, abnormal vaginal discharge, pH, clue cell, and positive whiff test (p<0.05). The findings also demonstrate that neither treatment was statistically different from the other for at least three of Amsel's criteria. CONCLUSION: This study shows that the effect of Cymbopogon olivieri on bacterial vaginosis is similar to that of metronidazole. Hence, Cymbopogon olivieri is a suitable option to treat bacterial vaginosis.

Is routine antibiotic prophylaxis warranted in dental implant surgery to prevent early implant failure? - a systematic review.

BACKGROUND: The question of whether antibiotic prophylaxis should be administered routinely for dental implant surgery is unresolved. Despite the lack of conclusive supportive evidence, antibiotics are often administered to reduce the risk of infection, which could lead to early implant failure. Increasing antibiotic resistance is a major concern and it is therefore important to reduce the overall use of antibiotics, including in dentistry. The aim of the present systematic review and meta-analysis was to evaluate the efficacy of preoperative antibiotics in preventing early implant failure, in overall healthy patients undergoing dental implant surgery. METHODS: An electronic search was undertaken of PubMed (Medline), Web of Science and the Cochrane Library up to October 1st, 2023, to identify randomized clinical trials (RCTs). All RCTs comparing antibiotic prophylaxis with no antibiotics/placebo in overall healthy patients receiving dental implants were included. The primary outcome was patients with early implant failure. Risk of bias was assessed, data were extracted, a meta-analysis was done, and GRADE certainty-of-evidence ratings were determined. The risk ratio (RR), the risk difference (RD) and 95% confidence intervals (CI) were estimated. RESULTS: After removal of duplicates, 1086 abstracts were screened, and 17 articles were reviewed in full text. Seven RCTs with moderate or low risk of bias and with a total of 1859 patients and 3014 implants were included in the meta-analysis. With reference to early implant failure at patient level, the meta-analysis failed to disclose any statistically significant difference (RR: 0.66, 95% CI: 0.30-1.47) between antibiotic prophylaxis and a placebo. The risk difference was -0.007 (95% CI: -0.035-0.020) leading to a number needed to treat (NNT) of 143. CONCLUSION: Antibiotic prophylaxis for dental implant surgery does not seem to have any substantial effect on early implant failure ( ). The results do not support routine antibiotic prophylaxis for dental implant surgery.

Penetration of Antibiotics into Subcutaneous and Intramuscular Interstitial Fluid: A Meta-Analysis of Microdialysis Studies in Adults.

BACKGROUND AND OBJECTIVE: The interstitial fluid of tissues is the effect site for antibiotics targeting extracellular pathogens. Microdialysis studies investigating these concentrations in muscle and subcutaneous tissue have reported notable variability in tissue penetration. This study aimed to comprehensively summarise the existing data on interstitial fluid penetration in these tissues and to identify potential factors influencing antibiotic distribution. METHODS: A literature review was conducted, focusing on subcutaneous and intramuscular microdialysis studies of antibiotics in both adult healthy volunteers and patients. Random-effect meta-analyses were used to aggregate effect size estimates of tissue penetration. The primary parameter of interest was the unbound penetration ratio, which represents the ratio of the area under the concentration-time curve in interstitial fluid relative to the area under the concentration-time curve in plasma, using unbound concentrations. RESULTS: In total, 52 reports were incorporated into this analysis. The unbound antibiotic exposure in the interstitial fluid of healthy volunteers was, on average, 22% lower than in plasma. The unbound penetration ratio values were higher after multiple dosing but did not significantly differ between muscle and subcutaneous tissue. Unbound penetration ratio values were lower for acids and bases compared with neutral antibiotics. Neither the molecular weight nor the logP of the antibiotics accounted for the variations in the unbound penetration ratio. Obesity was associated with lower interstitial fluid penetration. Conditions such as sepsis, tissue inflammation and tissue ischaemia were not significantly associated with altered interstitial fluid penetration. CONCLUSIONS: This study highlights the variability and generally lower exposure of unbound antibiotics in the subcutaneous and intramuscular interstitial fluid compared with exposure in plasma. Future research should focus on understanding the therapeutic relevance of these differences and identify key covariates that may influence them.

Pharmacokinetics of ceftiofur crystalline-free acid in plasma and seminal plasma in beef bulls.

The objective of this study was to compare the plasma (PL) and seminal plasma (SP) pharmacokinetic profile of ceftiofur (CEFT) and desuroylceftiofur acetamide (DFCA) after administration of CEFT crystalline-free acid (CCFA) by SC route in two sites of the ear in beef bulls. Four clinically healthy Hereford bulls received a comprehensive physical exam and subsequently a breeding-soundness examination, CBC, and chemistry profile panel. All bulls were diagnosed healthy and satisfactory potential breeders. In one group (n = 2), a single dose of CCFA was administered SC route at the base of the ear (BOE) at a dose of 6.6 mg/kg of body weight. The second group (n = 2) was also administered by SC route in the middle third of the posterior aspect of the ear (MTE). The concentrations of CEFT and DFCA in PL and SP were determined by a high-performance liquid chromatography mass spectrometry (HPLC-MS). Blood and semen samples were collected before the administration of CCFA and at 12, 24, 36, 48, 72, 96, 120, 144, and 168 h after injection. No levels of CEFT were detected in PL and only in 20 of the 40 SP samples (P = 0.0001). The mean level of CEFT in SP was 0.11 % in comparison with the DFCA level. DFCA was found in all PL and SP samples. Therefore, DFCA was chosen to be utilized in the study of the pharmacokinetics parameters both in PL and SP. There were no differences in the mean PL levels of DFCA for the two sites of SC administration between the BOE (102.9 ± 78.9 ng/mL; X ± SD) and to MTE (116.1 ± 70.2 ng/mL; P = 0.58). The mean SP levels of DFCA after administration in the BOE was 857 ± 747 ng/mL, and for the MTE was 549 ± 488 ng/mL without differences between both sites (P = 0.15). The mean level of DFCA in PL was 109.5 ± 74.0 ng/mL, which was lower than the mean SP levels of 695 ± 103 ng/mL (P = 0.001). Moreover, the PL peak DFCA concentration (Cmax) was 229 ± 46 ng/mL at 36.0 ± 29.4 h (Tmax) post-administration. The SP Cmax was 1851 ± 533 ng/mL at 30.0 ± 28.6 h (Tmax) post-administration. The Cmax between PL and SP were distinctive (P = 0.004) without any differences in Tmax between PL and SP (P = 0.60). The terminal half-life for PL DFCA (47.4 ± 29.3 h) was not different than in SP (53.1 ± 23.6 h; P = 0.77). The PL area under the curve concentration time from the first to the last sample (AUC0-last) was 18,984 ± 4841 ng/mL/h, which was significatively smaller compared with 125,677 ± 59,445 ng/mL/h for SP AUC0-last (P = 0.04). The PL mean residence time from the first to the last sample (MRT0-last) was 69.7 ± 15.1 h, and it was similar than for SP of 66.5 ± 7.7 h (P = 0.69). From the present investigation, based in its pharmacokinetic features, it was concluded that CCFA should be an appropriate antibiotic that could be used for the treatment of bull genital infections when its indication is properly outlined. To study the pharmacokinetics of CCFA in SP, DFCA metabolite was appropriated.

Pharmacokinetics and Histotoxic Profile of a Novel Azithromycin-Loaded Lipid-Based Nanoformulation.

Azithromycin traditional formulations possesses poor oral bioavailability which necessitates development of new formulation with enhanced bioavailability of the drug. The objective of current research was to explore the kinetics and safety profile of the newly developed azithromycin lipid-based nanoformulation (AZM-NF). In the in-vitro study of kinetics profiling, azithromycin (AZM) release was assessed using dialysis membrane enclosing equal quantity of either AZM-NF, oral suspension of azithromycin commercial product (AZM-CP), or azithromycin pure drug (AZM-PD) in simulated intestinal fluid. The ex-vivo study was performed using rabbit intestinal segments in physiological salts solution in a tissue bath. The in-vivo study was investigated by oral administration of AZM to rabbits while taking blood samples at predetermined time-intervals, followed by HPLC analysis. The toxicity study was conducted in rats to observe histopathological changes in rat's internal organs. In the in-vitro study, maximum release was 95.38 ± 4.58% for AZM-NF, 72.79 ± 8.85% for AZM-CP, and 46.13 ± 8.19% for AZM-PD (p < 0.0001). The ex-vivo investigation revealed maximum permeation of 85.68 ± 5.87 for AZM-NF and 64.88 ± 5.87% for AZM-CP (p < 0.001). The in-vivo kinetics showed Cmax 0.738 ± 0.038, and 0.599 ± 0.082 µg/ml with Tmax of 4 and 2 h for AZM-NF and AZM-CP respectively (p < 0.01). Histopathological examination revealed compromised myocardial fibers integrity by AZM-CP only, liver and kidney showed mild aberrations by both formulations, with no remarkable changes in the rest of studied organs. The results showed that AZM-NF exhibited significantly enhanced bioavailability with comparative safer profile to AZM-CP investigated.

Eradication Therapy for Helicobacter pylori Infection in Patients Receiving Hemodialysis: Review.

Patients receiving hemodialysis (HD) often develop gastrointestinal diseases. Recently, although in general population, clinical guidelines for Helicobacter pylori have strongly recommended its eradication in patients to prevent gastric cancer, optimal eradication regimen and optimal dosage of drugs for patients receiving HD have not been established, due to possible incidence of adverse events. Some antimicrobial agents used in eradication therapy, particularly amoxicillin, can exacerbate renal dysfunction. Given the delayed pharmacokinetics of drugs in patients receiving HD compared with those in healthy individuals, drug regimen and dosage should be considered to minimize adverse effects. Although previous studies have investigated the benefits of eradication therapy for patients receiving HD, because most studies were small in terms of the number of enrolled patients, it is hard to show evidence. The numbers of eradication in HD patients have recently increased, and it is important to provide an optimal regimen. The consideration of eradication in patients undergoing HD with a reduction in the drug dose by 1/2-1/3 may prevent adverse events. Additionally, another important consideration is whether adverse events can be prevented while maintaining a similar eradication rate with reduced drug dosages. Recent meta-analysis findings indicate comparable eradication rates in patients receiving HD and healthy individuals, both with the same dosage regimen and at a reduced dosage regimen, with no significant differences (relative risk [RR] for successful eradication: 0.85 [95% confidence interval (CI): 0.48-1.50]). Unlike with the same dosage regimen (RR for adverse events: 3.15 [95% CI: 1.93-5.13]), the adverse events in the dosage reduction regimen were similar to those in healthy individuals (RR: 1.26 [95% CI: 0.23-6.99]). From a pharmacological perspective, the eradication regimen in patients receiving HD should consider the dosage (1/2-1/3 dosage), dosing number (bid), dosing timing of drugs (after HD), and susceptibility to antimicrobial agents.

Portal vein thrombosis associated with acute cholecystitis.

ABSTRACT: Portal venous thrombosis (PVT) is an uncommon clinical problem and is rare following cholecystectomy. This article describes a patient who developed PVT after an initially uneventful laparoscopic cholecystectomy. The patient was successfully treated with IV antibiotics and anticoagulation.

Lemierre Syndrome: Clinical Challenges And The Anticoagulation Dilemma In Adolescent Care.

Lemierre syndrome is a rare, life-threatening condition characterized by an acute otorhinolaryngologic infection with septic thrombophlebitis of the internal jugular vein and septic embolism, particularly to the lungs. We describe a case of a previously healthy 15-year-old female patient who initially presents fever and odynophagia but quickly develops neck and pleuritic chest pain. Computed tomography was performed and the radiological findings confirmed the diagnosis of a Lemierre syndrome. She was managed with antibiotics, anticoagulant for three days and symptomatic treatment, with a gradually improving condition. After 17 days of hospitalisation, due to reappearance of pleuritic pain, a new imaging assessment was performed and showed additional septic emboli in the lungs, which prompted the reintroduction of anticoagulant therapy. Awareness of the existence of this syndrome is essential to ensure a radiological evaluation with computed tomography and thus timely diagnosis and treatment.

Integration of individual preclinical and clinical anti-infective PKPD data to predict clinical study outcomes.

The AIDA randomized clinical trial found no significant difference in clinical failure or survival between colistin monotherapy and colistin-meropenem combination therapy in carbapenem-resistant Gram-negative infections. The aim of this reverse translational study was to integrate all individual preclinical and clinical pharmacokinetic-pharmacodynamic (PKPD) data from the AIDA trial in a pharmacometric framework to explore whether individualized predictions of bacterial burden were associated with the trial outcomes. The compiled dataset included for each of the 207 patients was (i) information on the infecting Acinetobacter baumannii isolate (minimum inhibitory concentration, checkerboard assay data, and fitness in a murine model), (ii) colistin plasma concentrations and colistin and meropenem dosing history, and (iii) disease scores and demographics. The individual information was integrated into PKPD models, and the predicted change in bacterial count at 24 h for each patient, as well as patient characteristics, was correlated with clinical outcomes using logistic regression. The in vivo fitness was the most important factor for change in bacterial count. A model-predicted growth at 24 h of ≥2-log10 (164/207) correlated positively with clinical failure (adjusted odds ratio, aOR = 2.01). The aOR for one unit increase of other significant predictors were 1.24 for SOFA score, 1.19 for Charlson comorbidity index, and 1.01 for age. This study exemplifies how preclinical and clinical anti-infective PKPD data can be integrated through pharmacodynamic modeling and identify patient- and pathogen-specific factors related to clinical outcomes - an approach that may improve understanding of study outcomes.

Oral Hygiene With Neutral Electrolyzed Water and Systemic Therapy Increases Gastric Helicobacter pylori Eradication and Reduces Recurrence.

OBJECTIVES: Helicobacter pylori gastric infection strongly correlates with gastric diseases such as chronic gastritis, functional dyspepsia, and complications such as peptic ulcers and gastric cancer. In developing countries, systemic therapies are not usually successful due to elevated antibiotic resistance. Additionally, oral H. pylori infection and periodontal disease correlate with gastric treatment failures. This study aimed to explore the effect of an integral therapy, comprising oral hygiene and concomitant systemic treatment, to increase the eradication of gastric infection and recurrences. MATERIALS AND METHODS: A prospective, randomized, four-arm, parallel-group, open-label clinical trial was conducted to investigate the efficacy of integral therapy to eradicate gastric H. pylori infection and avoid recurrences in double-positive (real-time PCR oral and gastric infection) patients. Oral hygiene involved mouthwash with neutral electrolyzed water (NEW), with or without periodontal treatment. One hundred patients were equally distributed into four groups: NS, NS-PT, NEW, and NEW-PT. All patients had concomitant systemic therapy and additionally, the following oral treatments: mouthwash with normal saline (NS), periodontal treatment and mouthwash with normal saline (NS-PT), mouthwash with NEW (NEW), and periodontal treatment and mouthwash with NEW (NEW-PT). Gastric and oral infection and symptoms were evaluated one and four months after treatments. RESULTS: Integral therapy with NEW-PT increased gastric eradication rates compared with NS or NS-PT (84%-96% vs. 20%-56%; p < 0.001). Even more, a protective effect of 81.2% (RR = 0.1877; 95% CI: 0.0658-0.5355; p = 0.0018) against recurrences and 76.6% (RR = 0.2439; 95% CI: 0.1380-0.4310; p < 0.001) against treatment failure (eradication of infection and associated symptoms) was observed in patients from the NEW and NEW-PT groups. CONCLUSIONS: Implementation of oral hygiene and systemic treatment can increase the eradication of gastric infection, associated symptoms, and recurrences. NEW is recommended as an antiseptic mouthwash due to its efficacy and short- and long-term safety.

Antibacterial and oral tissue effectiveness of a mouthwash with a novel active system of amine + zinc lactate + fluoride.

OBJECTIVES: Reflecting the need for an effective support for the daily oral hygiene routine of patients experiencing (symptoms of) gum inflammation, a new mouthwash has been developed containing an amine + zinc lactate + fluoride system. The in vitro efficacy of this product was assessed using traditional laboratory methods, as well as novel experimentation. MATERIALS AND METHODS: This mouthwash has been evaluated in a series of laboratory tests including two short interval kill tests (SIKTs), a 12-h (longer term) biofilm regrowth assay, a plaque glycolysis assay, and an aerobic, repeated exposure biofilm model, as well as tests for soft tissue uptake and LPS neutralization. RESULTS: Several laboratory studies demonstrate that a mouthwash containing an amine + zinc lactate + fluoride system provides short-term and long-term antibacterial activity. While the immediate efficacy of this formula has been shown to be driven by the presence of the amine, zinc lactate provides a long-term antibacterial effect, as well as is able to inhibit bacterial metabolism. CONCLUSIONS: This research provides the basis for understanding the mode of action of this new mouthwash formulation and explains the previously observed clinical efficacy of this formula against plaque and gingivitis.

Bacterascites caused by Salmonella spp. following a cesarean section: A case report.

RATIONALE: Bacterascites are a rare complication of cesarean sections (C/S). Here, we report the case of a patient with bacterascites after an emergent C/S. PATIENT CONCERN: A 41-year-old female reported diffuse abdominal tightness and pain for a week after C/S, who received C/S at 38 4/7 weeks due to superimposed preeclampsia and prolonged labor. DIAGNOSES: Bacterascites caused by Salmonella species after C/S was diagnosed. INTERVENTIONS: Initial treatment included cefmetazole and metronidazole. On day 2, paracentesis was performed, followed by albumin and hydroxyethyl starch administration. By day 3, the patient developed pulmonary edema, necessitating Lasix administration. On day 6, ascites culture revealed Salmonella species resistant to third-generation cephalosporins, leading to meropenem therapy adjustment. This resulted in improved symptoms. Meropenem was continued for 14 days to complete the treatment regimen. OUTCOMES: Follow-up ultrasonography revealed a decrease in ascites. As the patient clinical condition improved, she was discharged on day 20 and scheduled for outpatient department follow-up. No recurrence of ascites was observed during the subsequent follow-up period of 3 months. No ascites were noted 8 days after discharge. LESSONS: Postoperative bacterascites with Salmonella were diagnosed. Antibiotic treatment and therapeutic paracentesis were effective for this condition.

Use of the DMAIC Lean Six Sigma quality improvement framework to improve beta-lactam antibiotic adequacy in the critically ill.

Beta-lactam antibiotics are widely used in the intensive care unit due to their favorable effectiveness and safety profiles. Beta-lactams given to patients with sepsis must be delivered as soon as possible after infection recognition (early), treat the suspected organism (appropriate), and be administered at a dose that eradicates the infection (adequate). Early and appropriate antibiotic delivery occurs in >90% of patients, but less than half of patients with sepsis achieve adequate antibiotic exposure. This project aimed to address this quality gap and improve beta-lactam adequacy using the Define, Measure, Analyze, Improve, and Control Lean Six Sigma quality improvement framework. A multidisciplinary steering committee was formed, which completed a stakeholder analysis to define the gap in practice. An Ishikawa cause and effect (Fishbone) diagram was used to identify the root causes and an impact/effort grid facilitated prioritization of interventions. An intervention that included bundled education with the use of therapeutic drug monitoring (TDM; i.e. drug-level testing) was projected to have the highest impact relative to the amount of effort and selected to address beta-lactam inadequacy in the critically ill. The education and TDM intervention were deployed through a Plan, Do, Study, Act cycle. In the 3 months after "go-live," 54 episodes of beta-lactam TDM occurred in 41 unique intensive care unit patients. The primary quality metric of beta-lactam adequacy was achieved in 94% of individuals after the intervention. Ninety-four percent of clinicians gauged the education provided as sufficient. The primary counterbalance of antimicrobial days of therapy, a core antimicrobial stewardship metric, was unchanged over time (favorable result; P = .73). Application of the Define, Measure, Analyze, Improve, and Control Lean Six Sigma quality improvement framework effectively improved beta-lactam adequacy in critically ill patients. The approach taken in this quality improvement project is widely generalizable to other drugs, drug classes, or settings to increase the adequacy of drug exposure.

Defining complicated urinary tract infection and route of antibiotics in children presenting to the emergency department: a cohort study using the Melbourne RUPERT clinical score.

OBJECTIVES: Most children with uncomplicated urinary tract infections (UTI) can be managed with oral antibiotics. However, identifying those likely to fail oral and need intravenous antibiotics due to complicating features at presentation is challenging. We aimed to derive, validate and test a score to guide initial antibiotic route. DESIGN: This cohort study enrolled children both prospectively and retrospectively. Patients were divided into two groups based on whether they received intravenous or oral antibiotics after 24 hours, including those who switched between routes. Children diagnosed with confirmed UTI were used to derive then validate the score, comparing complicating clinical features between the two groups. Combinations of significantly differentiating features generated receiver operating characteristic curves and the optimal cut-off for intravenous antibiotic use was selected. SETTING: The emergency department of a tertiary paediatric hospital. PARTICIPANTS: All children aged 3 months-17 years with suspected UTI were eligible, and were included if they fulfilled the diagnostic criteria for UTI. OUTCOME MEASURES: The effectiveness of the derived clinical score to differentiate patients at presentation who had complicated UTI requiring ongoing intravenous antibiotics. RESULTS: There were 1240 patients, of whom 167 children aged 12 months-11 years with confirmed UTI comprised the derivation cohort. The combination of features that performed optimally (area under curve 0.85, 95% CI 0.79 to 0.91) were: rigors, urological abnormality, fever (≥38°C), emesis, recurrent (≥3) UTI, tachycardia: the RUPERT score (1 point each, maximum 6). A score ≥3 accurately classified route of antibiotics after 24 hours for 80% patients (sensitivity 77%, specificity 81%). For the 168 patients in the validation cohort, the score accurately classified 76% (sensitivity 67%, specificity 78%). The score tested well in 'probable' UTI and adolescents, and less well in infants. CONCLUSION: The Melbourne RUPERT score provides the first standardised, easy-to-use score to aid clinicians in deciding route of antibiotics for more complicated UTI in children. It now needs prospective validation.

L-carnitine co-administration prevents colistin-induced mitochondrial permeability transition and reduces the risk of acute kidney injury in mice.

Colistin is a polymyxin antibiotic currently experiencing renewed clinical interest due to its efficacy in the treatment of multidrug resistant (MDR) bacterial infections. The frequent onset of acute dose-dependent kidney injury, with the potential of leading to long-term renal damage, has limited its use and hampered adequate dosing regimens, increasing the risk of suboptimal plasma concentrations during treatment. The mechanism of colistin-induced renal toxicity has been postulated to stem from mitochondrial damage, yet there is no direct evidence of colistin acting as a mitochondrial toxin. The aim of this study was to evaluate whether colistin can directly induce mitochondrial toxicity and, if so, uncover the underlying molecular mechanism. We found that colistin leads to a rapid permeability transition of mitochondria isolated from mouse kidney that was fully prevented by co-incubation of the mitochondria with desensitizers of the mitochondrial transition pore cyclosporin A or L-carnitine. The protective effect of L-carnitine was confirmed in experiments in primary cultured mouse tubular cells. Consistently, the relative risk of colistin-induced kidney damage, calculated based on histological analysis as well as by the early marker of tubular kidney injury, Kim-1, was halved under co-administration with L-carnitine in vivo. Notably, L-carnitine neither affected the pharmacokinetics of colistin nor its antimicrobial activity against relevant bacterial strains. In conclusion, colistin targets the mitochondria and induces permeability transition thereof. L-carnitine prevents colistin-induced permeability transition in vitro. Moreover, L-carnitine co-administration confers partial nephroprotection in mice treated with colistin, without interfering with its pharmacokinetics and antibacterial activity.