Antibiotic Suppression Research Articles

Infectious Aortitis Due to Salmonella Species Masquerading as Lung Malignancy

Infectious aortitis is a rare but devastating vascular infection with mortality exceeding 40%. Early diagnosis is crucial but often hampered by radiographic mimickers. We report a patient who was thought to have lung cancer but ultimately found to have an infected aortic aneurysm and bacteremia owing to Salmonella species. Owing to surgical contraindications, he was treated palliatively with an initial regimen of intravenous ampicillin/sulbactam followed by lifelong oral antibiotic suppression. He ultimately rejected his diagnosis, discontinued medications, and was lost to follow-up. (Level of Difficulty: Intermediate.)

Spontaneous Pancreatic Pseudocyst-Superior Mesenteric Vein Fistula

ABSTRACT Pancreatic pseudocyst formation is a common complication of chronic pancreatitis. Rarely, a fistula develops between the pseudocyst and the portal venous system. We present a case of a 50-year-old man who was found to have a pancreatic pseudocyst-superior mesenteric vein fistula after being evaluated for several months of abdominal pain and weight loss. The patient was treated with endoscopic stenting of the pancreatic duct along with early enteral nutrition and suppressive antibiotics, which resulted in improvement in his condition. This case report highlights clinical presentation and the complexity of treatment of this rare diagnosis.

Very Long-term Outcomes After Electrofulguration for Antibiotic-refractory Recurrent Urinary Tract Infections in a Predominantly Menopausal Cohort of Women.

Antibiotic-refractory recurrent urinary tract infections are challenging to manage. Prior studies have shown that, in selected patients, electrofulguration of cystitis may disrupt potential nidus of recurrent urinary tract infections. We report on long-term outcomes of electrofulguration in women with at least 5 years of follow-up. Following Institutional Review Board approval, we analyzed a cohort of nonneurogenic women with ≥3 symptomatic recurrent urinary tract infections/y and inflammatory lesions on cystoscopy who underwent electrofulguration, excluding those with alternate identifiable etiology for recurrent urinary tract infections or less than 5-year follow-up. Preoperative characteristics, antibiotic regimens, and annual urinary tract infections were reported. Primary outcome was clinical cure (0-1 urinary tract infection/y), improvement (>1 and <3/y) or failure (≥3/y) at last follow-up. Secondary outcomes included need for antibiotics or repeat electrofulguration. A subanalysis was performed for women with >10-year follow-up. From 2006 to 2012, 96 women met study criteria with median age 64. Median follow-up was 11 years (IQR: 10-13.5); 71 women had >10-year follow-up. Prior to electrofulguration, 74% used daily antibiotic suppression, 5% used postcoital prophylaxis, 14% used self-start therapy, and 7% were not on prophylaxis. At last post-electrofulguration visit, 72% of women were cured, 22% improved, and 6% failed. Antibiotic usage decreased post-electrofulguration (P < .05). Five percent were on continuous antibiotics at last follow-up as compared to 74% on continuous antibiotics pre-electrofulguration (McNemar P < .05). Nineteen percent of women underwent a repeat electrofulguration. In menopausal women with over 5-year follow-up after electrofulguration for antibiotic-refractory recurrent urinary tract infections, there appears to be durable clinical cure and improvement, with decreased need for long-term antibiotics.

Dalbavancin as suppressive antibiotic therapy in patients with prosthetic infections: efficacy and safety.

Suppressive antibiotic therapy (SAT) is a strategy to alleviate symptoms and/or to reduce the progression of an infection when other treatment options cannot be used. Dalbavancin, due to its prolonged half-life, enables (bi) weekly dosing. Here, we report our multicenter real-life clinical experience with dalbavancin used as SAT in patients with prosthetic joint or vascular infections. Medical records of all adult patients with documented vascular or orthopedic chronic prosthetic infections, who received dalbavancin as SAT between 2016 and 2018 from four Spanish hospitals were reviewed for inclusion. Descriptive analysis of demographic characteristics, Charlson Comorbidity index, Barthel index, isolated pathogens and indication, concomitant antibiotic use, adverse events, and clinical outcome of SAT were performed. Eight patients were eligible for inclusion, where six patients had prosthetic vascular infections (aortic valve) and two patients had knee prosthetic joint infections. The most common pathogens were methicillin-susceptible Staphylococcus aureus and Enterococcus faecium. All patients had a history of prior antibiotic treatment for the prosthetic infection [median duration of antibiotic days 125days (IQR, 28-203days)]. The median number of dalbavancin doses was 29 (IQR, 9-61) and concomitant antibiotic use (n = 5, 62.5%). Clinical success was reported in 75% (n = 6) of patients. Adverse events were reported in two patients (mild renal and hepatic impairment). The median estimated cost savings due to the avoided hospital days was €60185 (IQR, 19,916-94984) per patient. Despite the limitations of our study, this preliminary data provides valuable insight to support further evaluation of dalbavancin for SAT in patients with prosthetic infections in the outpatient setting when alternative treatments are not feasible.

Reevaluación del diagnóstico y el tratamiento de las infecciones de dispositivos de electroestimulación cardiaca mediante [18F]FDG-PET/TC

Introduction and objectivesThe role of [18F]FDG-PET/CT in cardiac implantable electronic device (CIED) infections requires better evaluation, especially in the diagnosis of systemic infections. We aimed to determine the following: a) the diagnostic accuracy of [18F]FDG-PET/CT in each CIED topographical region, b) the added value of [18F]FDG-PET/CT over transesophageal echocardiography (TEE) in diagnosing systemic infections, c) spleen and bone marrow uptake in differentiating isolated local infections from systemic infections, and d) the potential application of [18F]FDG-PET/CT in follow-up. MethodsRetrospective single-center study including 54 cases and 54 controls from 2014 to 2021. The Primary endpoint was the diagnostic yield of [18F]FDG-PET/CT in each topographical CIED region. Secondary analyses described the performance of [18F]FDG-PET/CT compared with that of TEE in systemic infections, bone marrow and spleen uptake in systemic and isolated local infections, and the potential application of [18F]FDG-PET/CT in guiding cessation of chronic antibiotic suppression when completed device removal is not performed. ResultsWe analyzed 13 (24%) isolated local infections and 41 (76%) systemic infections. Overall, the specificity of [18F]FDG-PET/CT was 100% and sensitivity 85% (79% pocket, 57% subcutaneous lead, 22% endovascular lead, 10% intracardiac lead). When combined with TEE, [18F]FDG-PET/CT increased definite diagnosis o fsystemic infections from 34% to 56% (P=.04). Systemic infections with bacteremia showed higher spleen (P=.05) and bone marrow metabolism (P=.04) than local infections. Thirteen patients without complete device removal underwent a follow-up [18F]FDG-PET/CT, with no relapses after discontinuation of chronic antibiotic suppression in 6 cases with negative follow-up [18F]FDG-PET/CT. ConclusionsThe sensitivity of [18F]FDG-PET/CT for evaluating CIED infections was high in local infections but much lower in systemic infections. However, accuracy increased when [18F]FDG-PET/CT was combined with TEE in endovascular lead bacteremic infection. Spleen and bone marrow hypermetabolism could differentiate bacteremic systemic infection from local infection. Although further prospective studies are needed, follow-up [18F]FDG-PET/CT could play a potential role in the management of chronic antibiotic suppression therapy when complete device removal is unachievable.

Irrigation and Debridement With Chronic Antibiotic Suppression for the Management of Acutely Infected Aseptic Revision Total Joint Arthroplasties

BackgroundMost data on irrigation and debridement with component retention (IDCR) as a treatment for acute periprosthetic joint infections (PJIs) focuses on primary total joint arthroplasties (TJAs). However, the incidence of PJI is greater after revisions. We investigated the outcomes of IDCR with suppressive antibiotic therapy (SAT) following aseptic revision TJAs. MethodsThrough our total joint registry, we identified 45 aseptic revision TJAs (33 hips, 12 knees) performed from 2000 to 2017 that were treated with IDCR for acute PJI. Acute hematogenous PJI was present in 56%. Sixty-four percent of PJIs involved Staphylococcus. All patients were treated with 4 to 6 weeks of intravenous antibiotics with the intention to treat with SAT (89% received SAT). The mean age was 71 years (range, 41 to 90), with 49% being women and a mean body mass index of 30 (range, 16 to 60). The mean follow-up was 7 years (range, 2 to 15). ResultsThe 5-year survivorships free from re-revision for infection and reoperation for infection were 80% and 70%, respectively. Of the 13 reoperations for infection, 46% involved the same species as the initial PJI. The 5-year survivorships free from any revision and any reoperation were 72% and 65%, respectively. The 5-year survivorship free from death was 65%. ConclusionAt 5 years following IDCR, 80% of implants were free from re-revision for infection. As the penalty for implant removal is often high in revision TJAs, IDCR with SAT is a viable option for acute infection after revision TJAs in select patients. Level of EvidenceIV.

P.139 Cerebral toxoplasmosis in an HIV-negative patient

Background: Toxoplasma gondii is a protozoan parasite with the ability to infect any nucleated cell in humans. Most immunocompetent infected individuals are asymptomatic. Latent toxoplasma can become reactivated in immunocompromised individuals though this is exceptionally rare in HIV-negative individuals. Methods: We present the case of a 47-year-old male with chronic immunosuppression secondary to marginal zone lymphoma and steroid therapy. Results: The patient presented to hospital with a 1-week history of word-finding difficulties, intermittent right facial numbness and leg weakness, and tonic-clonic seizures. CT head showed a left temporal heterogenous mass measuring 2.8 × 2.8 × 3.5 cm. Biopsy of the lesion showed Multiple tachyzoites and rare bradyzoites with strong positivity for the toxoplasma specific immunostain. The patient was treated with trimethoprim/sulfamethoxazole which resulted in complete neurologic recovery. Conclusions: Our literature review included 32 cases of cerebral toxoplasmosis in HIV-negative patients with an overall mortality rate of 48%. Cerebral toxoplasmosis has a predilection for immunosuppressed patients with an underlying hematologic malignancy (74%, n= 23). Successful treatment requires early recognition of the disease and prompt treatment with sulfamethoxazole and trimethoprim, pyrimethamine, or sulfadiazine. Patients who recover from acute toxoplasmosis should remain on lifelong suppressive antibiotic therapy to prevent relapse.

What's New in Musculoskeletal Infection.

What's New in Musculoskeletal Infection.

Reappraisal of [18F]FDG-PET/CT for diagnosis and management of cardiac implantable electronic device infections

Introduction and objectivesThe role of [18F]FDG-PET/CT in cardiac implantable electronic device (CIED) infections requires better evaluation, especially in the diagnosis of systemic infections. We aimed to determine the following: a) the diagnostic accuracy of [18F]FDG-PET/CT in each CIED topographical region, b) the added value of [18F]FDG-PET/CT over transesophageal echocardiography (TEE) in diagnosing systemic infections, c) spleen and bone marrow uptake in differentiating isolated local infections from systemic infections, and d) the potential application of [18F]FDG-PET/CT in follow-up. MethodsRetrospective single-center study including 54 cases and 54 controls from 2014 to 2021. The Primary endpoint was the diagnostic yield of [18F]FDG-PET/CT in each topographical CIED region. Secondary analyses described the performance of [18F]FDG-PET/CT compared with that of TEE in systemic infections, bone marrow and spleen uptake in systemic and isolated local infections, and the potential application of [18F]FDG-PET/CT in guiding cessation of chronic antibiotic suppression when completed device removal is not performed. ResultsWe analyzed 13 (24%) isolated local infections and 41 (76%) systemic infections. Overall, the specificity of [18F]FDG-PET/CT was 100% and sensitivity 85% (79% pocket, 57% subcutaneous lead, 22% endovascular lead, 10% intracardiac lead). When combined with TEE, [18F]FDG-PET/CT increased definite diagnosis o fsystemic infections from 34% to 56% (P=.04). Systemic infections with bacteremia showed higher spleen (P=.05) and bone marrow metabolism (P=.04) than local infections. Thirteen patients without complete device removal underwent a follow-up [18F]FDG-PET/CT, with no relapses after discontinuation of chronic antibiotic suppression in 6 cases with negative follow-up [18F]FDG-PET/CT. ConclusionsThe sensitivity of [18F]FDG-PET/CT for evaluating CIED infections was high in local infections but much lower in systemic infections. However, accuracy increased when [18F]FDG-PET/CT was combined with TEE in endovascular lead bacteremic infection. Spleen and bone marrow hypermetabolism could differentiate bacteremic systemic infection from local infection. Although further prospective studies are needed, follow-up [18F]FDG-PET/CT could play a potential role in the management of chronic antibiotic suppression therapy when complete device removal is unachievable.

MP19-06 ANTIBIOTIC USE, BEST PRACTICE STATEMENT ADHERENCE, AND UTI RATE FOR INTRADETRUSOR ONABOTULINUMTOXIN A INJECTION FOR OVERACTIVE BLADDER: A MULTI-INSTITUTIONAL COLLABORATION FROM THE SUFU RESEARCH NETWORK

You have accessJournal of UrologyCME1 Apr 2023MP19-06 ANTIBIOTIC USE, BEST PRACTICE STATEMENT ADHERENCE, AND UTI RATE FOR INTRADETRUSOR ONABOTULINUMTOXIN A INJECTION FOR OVERACTIVE BLADDER: A MULTI-INSTITUTIONAL COLLABORATION FROM THE SUFU RESEARCH NETWORK Katherine Shapiro, Monica van Til, Stephanie Daignault-Newton, Giulia Lane, Ariana Smith, Una Lee, Anne Suskind, Jennifer Anger, Doreen Chung, W. Stuart Reynolds, Anne Cameron, Christopher Tenggardjaja, Priya Padmanabhan, Benjamin Brucker, and Sufu Research Network Katherine ShapiroKatherine Shapiro More articles by this author , Monica van TilMonica van Til More articles by this author , Stephanie Daignault-NewtonStephanie Daignault-Newton More articles by this author , Giulia LaneGiulia Lane More articles by this author , Ariana SmithAriana Smith More articles by this author , Una LeeUna Lee More articles by this author , Anne SuskindAnne Suskind More articles by this author , Jennifer AngerJennifer Anger More articles by this author , Doreen ChungDoreen Chung More articles by this author , W. Stuart ReynoldsW. Stuart Reynolds More articles by this author , Anne CameronAnne Cameron More articles by this author , Christopher TenggardjajaChristopher Tenggardjaja More articles by this author , Priya PadmanabhanPriya Padmanabhan More articles by this author , Benjamin BruckerBenjamin Brucker More articles by this author , and Sufu Research Network More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003244.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Onabotulinumtoxin A (BTX-A) is a well-established treatment for overactive bladder (OAB). The American Urological Association (AUA) 2008 Antibiotic Best Practice Statement recommended trimethoprim-sulfamethoxazole or fluoroquinolone for cystoscopy with manipulation. The aim of the study was to evaluate concordance with antibiotic best practices at the time of BTX-A injection and urinary tract infection (UTI) rates based on antibiotic regimen. METHODS: We included men and women undergoing first-time BTX-A injection for idiopathic OAB with 100 units in 2016 within the SUFU Research Network multi-institutional retrospective database. Patients on suppressive antibiotics were excluded. The primary outcome was concordance of periprocedural antibiotic use with the AUA 2008 Best Practice Statement. As a secondary outcome we compared the incidence of UTI at 15 days and 30 days after BTX-A among women. 15 days was used as a cutoff for a UTI attributed to BTX-A injection procedure, whereas a UTI within 30 days was considered a chronic effect of BTX-A. We assumed that patients who were not seen in the first 15 days did not have a UTI within 15 days. Fisher’s exact tests were applied for categorical variables. RESULTS: Of the cohort of 216 patients (175 women, 41 men) undergoing BTX-A, 24 different periprocedural antibiotic regimens were utilized. Among patients who had in-office visits within 15 days of BTX-A, 87% received periprocedural antibiotics and 47% received best practice statement-concordant antibiotics. There was no significant difference in UTI events between patients who received any antibiotics and those that did not at 15 day follow up (N=173, 6% vs 9%, p=0.4). Of patients who received antibiotics, UTI rates did not vary significantly depending on concordance with recommendations or not (N=133, 5% vs 7%, p=0.7). 81% of the 216 patients with 30-day follow up received periprocedural antibiotics. Of those, 47% received best practice statement-concordant antibiotics. At 30 days, there was no significant difference in UTI events based on antibiotic use (N=173, 11% antibiotics vs 16% no antibiotics, p=0.5) or best practice statement concordance or not 8% vs 16% (N=133, p=0.13). CONCLUSIONS: This retrospective multi-institutional study demonstrates that antibiotic regimens and adherence to the AUA Best Practice Statement was variable among providers and that UTI rates at 15 or 30 days following BTX-A did not vary significantly regardless of antibiotic use or alignment with best practices. Source of Funding: SUFU Research Network © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e266 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Katherine Shapiro More articles by this author Monica van Til More articles by this author Stephanie Daignault-Newton More articles by this author Giulia Lane More articles by this author Ariana Smith More articles by this author Una Lee More articles by this author Anne Suskind More articles by this author Jennifer Anger More articles by this author Doreen Chung More articles by this author W. Stuart Reynolds More articles by this author Anne Cameron More articles by this author Christopher Tenggardjaja More articles by this author Priya Padmanabhan More articles by this author Benjamin Brucker More articles by this author Sufu Research Network More articles by this author Expand All Advertisement PDF downloadLoading ...

High rate of failure after revision extensor mechanism allograft reconstruction

BackgroundPatients who fail initial extensor mechanism allograft (EMA) reconstruction for extensor mechanism disruption after total knee arthroplasty (TKA) are left with few options. This study evaluated outcomes in patients that underwent revision EMA reconstruction following a failed EMA. MethodTen patients that underwent revision EMA for failed index EMA with minimum 1-year follow-up were retrospectively reviewed. Patients receiving fresh-frozen EMA (quadriceps tendon, patella, patellar tendon, and tibial tubercle) at index and revision EMA were included. The primary outcome was EMA failure defined as revision surgery, extensor lag > 30°, or Knee Society Score (KSS) < 60 at last follow-up. Descriptive statistics were performed, with p < 0.05. ResultsMean extensor lag improved from 55.6°±26.7° pre-revision to 32.8°±29.6° (p = 0.13) at mean follow-up of 43.8 months (range, 12–124 months). Mean KSS improved from 41.0 ± 9.5 pre-revision to 73.4 ± 14.5 at last follow-up (p < 0.001). All patients required assistive devices for ambulation at final follow-up: one (10.0%) required a wheelchair, five (50.0%) required a walker, and four (40.0%) required a cane. Seven (70.0%) patients experienced EMA failure at a mean of 33.6 months (range, 2–124) following revision EMA: three (30.0%) were revised for periprosthetic joint infection (one of which also had extensor lag > 30°), three (30.0%) additional patients had extensor lag > 30°, and one (10.0%) patient had KSS < 60 (this patient developed PJI and was treated nonoperatively with chronic antibiotic suppression). ConclusionsRevision EMA reconstruction fails at a high rate despite leading to improvements in KSS. Further research is needed to develop effective prevention and treatment strategies for failure after initial EMA reconstruction.

Poor outcome after debridement and implant retention for acute hematogenous periprosthetic joint infection: a cohort study of 43 patients

The management of acute hematogenous periprosthetic joint infection (AHI) is challenging and the optimal treatment is not clearly defined. The aim of this study was to evaluate the treatment outcome of AHI, and secondarily to investigate potential risk factors that affect outcome. We retrospectively analyzed 43 consecutive AHIs in a total hip or knee arthroplasty between 2013 and 2020 at a single center. We used the Delphi international consensus criteria to define infection. Patients were treated by either debridement, antibiotics, and implant retention (DAIR) (n = 25), implant exchange/removal (n = 15), or suppressive antibiotics only (n = 3). AHI was defined as abrupt symptoms of infection ≥ 3 months after implantation in an otherwise well-functioning arthroplasty. AHI was most often caused byStaphylococcus aureus(16/43) and streptococcal species (13/43), but a broad spectrum of microbes were identified. 25 of 43 were treated with DAIR, with success in 10 of 25, which was significantly lower than in patients treated with removal of the implant with success in 14 of 15.S. aureusinfection, knee arthroplasty, and implant age < 2 years were associated with treatment failure. The 2-year mortality rate was 8 of 43. The outcome following DAIR in AHIs was poor. The majority of infections were caused by virulent microbes, and we found a high mortality rate. Removal of the implant should more often be considered.

Ocular toxoplasmosis during frontline venetoclax therapy for chronic lymphocytic leukaemia - more than meets the eye.

A 67-year-old woman presented with a right central scotoma and reduced Snellen visual acuity (<6/60), 4 months after commencing frontline obinutuzumab–venetoclax (Ven–O) therapy for 13q-deleted, IGHV-mutated, chronic lymphocytic leukaemia (CLL). At the time of ocular symptoms, her full blood count comprised haemoglobin 131 g/L, lymphocytes 0.7 × 109/L, neutrophils 0.8 × 109/L, platelets 40 × 109/L and total IgG < 3.2 g/L. Repeat bone marrow trephine revealed minor residual CLL only (5%–10%). She received valaciclovir only as supportive therapy. Serial ophthalmic examinations demonstrated an enlarging macular lesion with mild vitritis consistent with retinochoroiditis (retinal photograph, Figure 2 without satellite lesions or evidence of pre-existing retinal scarring. Spectral-domain optical coherence tomography Figure 1 revealed full-thickness retinal necrosis with hyper-reflectivity and disorganisation of retinal layers. Polymerase chain reaction (PCR) of aqueous humour demonstrated the presence of Toxoplasma gondii, consistent with active ocular toxoplasmosis. T. gondii IgG but no IgM antibodies were detected both pre-treatment and 4 weeks from the onset of ocular symptoms. Computed tomography imaging of the brain was normal, and serum T. gondii PCR was negative. T. gondii is a common infectious cause of retinochoroiditis. Both acquired ocular toxoplasmosis and reactivation of previous infection may be observed in immune-competent individuals. Ocular toxoplasmosis has also been described in relapsed/refractory CLL, including those treated with continuous venetoclax. Prior fludarabine exposure has been cited as a risk factor for opportunistic infection. However, reports of toxoplasmosis during frontline CLL therapy are limited and, to our knowledge, have not included the Ven–O combination. The patient completed systemic and intra-vitreal clindamycin with topical prednisolone drops, noting gradual improvement of her visual acuity to 6/36 and slow healing of the macular lesion on serial examination. Given the quantitative immune dysfunction observed and evidence of past T. gondii infection, opportunistic reactivation of toxoplasmosis was considered. However, the absence of pre-existing toxoplasmosis retinal scar or bilateral ocular involvement argued against infection reactivation. Absence of infection dissemination, including no central nervous system involvement as seen with acquired immune deficiency syndromes such as HIV, also argue against infection occurring as a function of immune compromise. Nonetheless, our patient remains on suppressive antibiotic therapy during Ven–O therapy and 4-weekly prophylactic intravenous immunoglobulin. This case highlights the complexities of infection diagnoses and management in the context of frontline novel therapies in CLL. Appropriate supportive treatments remain uncertain. Rory Bennett, Lyndell L. Lim, Constantine S. Tam interpreted the case information and wrote the manuscript. CST: Honoraria for AbbVie, AstraZeneca, Janssen, BeiGene and LOXO. Research funding from AbbVie, Janssen and BeiGene Documented verbal consent obtained from the patient prior to preparation of manuscript.

Macrolactin A mediated biocontrol of Fusarium oxysporum and Rhizoctonia solani infestation on Amaranthus hypochondriacus by Bacillus subtilis BS-58.

Plant diseases are one of the main hurdles for successful crop production and sustainable agriculture development world-wide. Though several chemical measures are available to manage crop diseases, many of them have serious side effects on humans, animals and the environment. Therefore, the use of such chemicals must be limited by using effective and eco-friendly alternatives. In view of the same, we found a Bacillus subtilis BS-58 as a good antagonist towards the two most devastating phytopathogens, i.e., Fusarium oxysporum and Rhizoctonia solani. Both the pathogens attack several agricultural crops (including amaranth) and induce a variety of infections in them. The findings of scanning electron microscopy (SEM) in this study suggested that B. subtilis BS-58 could inhibit the growth of both the pathogenic fungi by various means such as perforation, cell wall lysis, and cytoplasmic disintegration in the fungal hyphae. Thin-layer chromatography, LC-MS and FT-IR data revealed the antifungal metabolite to be macrolactin A with a molecular weight of 402 Da. Presence of the mln gene in the bacterial genome further endorsed that the antifungal metabolite produced by BS-58 was macrolactin A. Pot trial conducted in the present study showed that seed treatment by BS-58 effectively reduced seedling mortality (54.00 and 43.76%) in amaranth, when grown in pathogen infested soil (F. oxysporum and R. solani, respectively), when compared to their respective negative controls. Data also revealed that the disease suppression ability of BS-58 was almost equivalent to the recommended fungicide, carbendazim. SEM analysis of roots of the seedlings recovered from pathogenic attack substantiated the hyphal disintegration by BS-58 and prevention of amaranth crop. The findings of this study conclude that macrolactin A produced by B. subtilis BS-58 is responsible for the inhibition of both the phytopathogens and the suppression of the diseases caused by them. Being native and target specific, such strains under suitable conditions, may result in ample production of antibiotic and better suppression of the disease.

Safety of total elbow arthroplasty in patients with rheumatoid arthritis and prior hip or knee periprosthetic joint infection

BackgroundThe volumes of upper and lower extremity arthroplasty are increasing. Periprosthetic joint infection (PJI) after TEA remains a substantial cause of morbidity, with certain studies reporting primary total elbow arthroplasties (TEA) PJI rates over 10%. The odds ratio for hip and knee PJI after previous hip or knee PJI is 3 times, and it rises to 15 times for patients on chronic suppressive antibiotics. The risk of PJI for primary TEA in patients with a history of lower extremity PJI is unknown. The purpose of this study, therefore, was to compare the incidence of PJI after primary TEA in patients with a history of lower extremity PJI in a case-control study. MethodsOur institutional joint registry database was queried to identify all patients who underwent primary TEA and had previously undergone treatment for lower extremity PJI between 1974 and 2021. Twelve elbows (10 patients) with a mean follow-up of 8.2 years were identified. There were 9 female elbows (75%) and 3 male elbows (25%) with a mean age of 63 years (range,44-78 years), and all patients had a diagnosis of rheumatoid arthritis. This cohort was 1:7 matched (age, sex, side, indication, and surgical year) to 84 elbows (83 patients) with no history of lower extremity PJI. There were no statistically significant differences between the cohorts with regard to body mass index or operative time. Survivorship analysis free of TEA PJI with death as a competing risk was calculated. ResultsNone of the 12 TEA included in the study group developed PJI. The cumulative incidence of PJI in the matched cohort at 10 years was 6.4% (5 elbows). There was 1 superficial infection in the study group (9.1%) and 5 (5.8%) in the matched cohort. In the study group, 2 elbows underwent revision and 4 underwent reoperation. Eight elbows in the matched cohort underwent revision and 23 underwent reoperation. The study cohort was associated with higher risk of revision and reoperation for any cause, but these differences did not reach statistical significance. ConclusionIn this relatively small case control study, there was no incidence of PJI in patients who underwent primary TEA for rheumatoid arthritis and had previously undergone treatment for lower extremity PJI. The cumulative incidence of PJI in the matched cohort at 10 years was 6.4%. Although underpowered to make firm conclusions, it does draw from a very large population of patients and did not reveal an association between infection after TEA and a prior history of lower extremity PJI.

AUSTRALIAN CAPITAL TERRITORY PROSTHETIC JOINT INFECTION DATABASE: ANALYSIS OF THE FIRST 100 PATIENTS

Prosthetic joint infections (PJI) are one of the most devastating complications of joint replacement surgery. They are associated with significant patient morbidity and carry a significant economic cost to treat. The management of PJI varies from antibiotic suppression, debridement, antibiotics, and implant retention (DAIR) procedures through to single/multiple stage revision procedures. Concerns have been raised recently in relation to the rising number of revision arthroplasty procedures that are being undertaken in relation to infection. This database aims to collect data on all PJIs that have been managed in the Australian Capital Territory (ACT) region. This will allow us to investigate the microbial trends, outcomes of surgical intervention and patient outcomes within our local population.This database will incorporate diagnostic, demographic, microbiological and treatment information in relation to local PJI cases. The data will be collated from the local infectious diseases database, hospital medical records, and where available the Australian Orthopaedic Association National Joint Replacement Registry Data.The first 100 cases of PJI were assessed. 76% were defined as being acute. 56% of the patients received antibiotics prior to their diagnosis however only 3% were culture negative. 89% were monomicrobial and 11% polymicrobial. The intended management strategy was a DAIR in 38% of patients and a 2-stage revision in 12% of cases. The intended management strategy was successful in 46% of the patients.The ACT is uniquely placed to analyze and create a local PJI database. This will allow us to guide further treatment and local guidelines in terms of management of these complex patients.

MANAGEMENT OF PERIPROSTHETIC JOINT INFECTION FOLLOWING TOTAL JOINT ARTHROPLASTY: EXPERIENCE FROM A RURAL CENTRE

Prosthetic joint infection (PJI) remains one of the most challenging complications to manage following total joint arthroplasty (TJA). There is a paucity of published data on the management of PJI in smaller, rural hospital settings. In this study, we investigate [1] the success rate of surgical management for PJI following TJA and [2] the microbiology of infecting organisms in this unique geographical environment.We performed a retrospective single-centre study at a rural hospital (Southland Hospital, Invercargill, New Zealand) over a 3-year period (2019 to 2022). All patients presenting with a first episode of PJI fulfilling Musculoskeletal Infection Society criteria after hip or knee arthroplasty were included. All patients had a minimum follow up of 6 months. Treatment success was defined eradication of infection.Twenty-one cases (14 hips and 7 knees) were identified. These were managed with Debridement, antibiotics, and implant retention (DAIR) procedure (n=14, 67%), single-stage revision (n=6, 29%), or long-term suppressive antibiotics (n=1, 4%). Of the DAIR patients, infection recurred in 50% and underwent subsequent revision. Of the single-stage revision patients, 17% failed and underwent subsequent revision. The overall success rate was 90%. Methicillin-sensitive Staphylococcus aureus (MSSA) was the most isolated pathogen (57%,) with no methicillin-resistance Staphylococcus aureus (MRSA) identified. Overall, 90% of infecting organisms were cefazolin sensitive.These results suggest that management of PJI is a safe and viable treatment option when performed in a rural hospital setting, with comparable treatment success rates to urban centres. The incidence of MRSA is low in this setting. Rates of antibiotic resistance were relatively low and most organisms were sensitive to cefazolin, the routine antibiotic used in prophylaxis.

Risk factors for recurrent infection in the surgical treatment of infected massive endoprostheses implanted for musculoskeletal tumours

BackgroundInfection is a devastating complication of endoprosthetic replacement (EPR) in orthopaedic oncology. Surgical treatments include debridement and/or one- or two-stage exchange. This study aims to determine the infection-free survival after surgical treatment for first and recurrent EPR infections and identify the risk factors associated with infection recurrence.MethodsThis single-centre cohort study included all patients with primary bone sarcomas or metastatic bone disease treated for infected EPR between 2010 and 2020. Variables included soft tissue status using McPherson classification, tumour type, silver coating, chemotherapy, previous surgery and microorganisms identified. Data for all previous infections were collected.Survival analysis, with time to recurrent infection following surgical treatment, was calculated at 1, 2 and 4 years. Cox regression analysis was used to assess the influence of different variables on recurrent infection.ResultsThe cohort included 99 patients with a median age of 44 years (29–58 IQR) at the time of surgical treatment. The most common diagnoses were osteosarcoma and chondrosarcoma.One hundred and thirty-three surgical treatments for first or subsequent infections were performed. At 2 years of follow-up, overall success rates were as follows: two-stage exchange 55.3%, one-stage exchange 45.5%, DAIR with an exchange of modular components 44.6% and DAIR without exchange of modular components 24.7%.Fifty-one (52%) patients were infection-free at the most recent follow-up. Of the remaining 48 patients, 27 (27%) were on antibiotic suppression and 21 (21%) had undergone amputation.Significant risk factors for recurrent infection were the type of surgical treatment, with debridement alone as the highest risk (HR 4.75: 95%CI 2.43–9.30; P < 0.001); significantly compromised soft tissue status (HR 4.41: 95%CI 2.18–8.92; P = 0.001); and infections due to Enterococcus spp.. (HR 7.31: 95%CI 2.73–19.52); P = 0.01).ConclusionsTwo-stage exchange with complete removal of all components where feasible is associated with the lowest risk of recurrent infection. Poor soft tissues and enterococcal infections are associated with higher risks of recurrent infection. Treatment demands an appropriate multidisciplinary approach. Patients should be counselled appropriately about the risk of recurrent infection before embarking on complex treatment.

Real-life temocillin use in Greater Paris area, effectiveness and risk factors for failure in infections caused by ESBL-producing Enterobacterales: a multicentre retrospective study.

Temocillin is a β-lactam that is not hydrolysed by ESBLs. To describe the real-life use of temocillin, to assess its effectiveness in infections caused by ESBL-producing Enterobacterales, and to identify risk factors for treatment failure. Retrospective multicentric study in eight tertiary care hospitals in the Greater Paris area, including patients who received at least one dose of temocillin for ESBL infections from 1 January to 31 December 2018. Failure was a composite criterion defined within 28 day follow-up by persistence or reappearance of signs of infection, and/or switch to suppressive antibiotic treatment and/or death from infection. A logistic regression with univariable and multivariable analysis was performed to identify risks associated with failure. Data on 130 infection episodes were collected; 113 were due to ESBL-producing Enterobacterales. Mean age was 65.2 ± 15.7 years and 68.1% patients were male. Indications were mostly urinary tract infections (UTIs) (85.8%), bloodstream infections (11.5%), respiratory tract infections (RTIs) (3.5%) and intra-abdominal infections (3.5%). Bacteria involved were Escherichia coli (49.6%), Klebsiella pneumoniae (44.2%) and Enterobacter cloacae (8.8%). Polymicrobial infections occurred in 23.0% of cases. Temocillin was mostly used in monotherapy (102/113, 90.3%). Failure was found in 13.3% of cases. Risk factors for failure in multivariable analysis were: RTI (aOR 23.3, 95% CI 1.5-358.2) and neurological disease (aOR 5.3, 95% CI 1.5-18.6). The main use of temocillin was UTI due to ESBL-producing E. coli and K. pneumoniae, with a favourable clinical outcome. The main risk factor for failure was neurological disease.

999. Clinical Outcomes of Off-label Dalbavancin Use within an Outpatient Parenteral Antibiotic Therapy (OPAT) Program

Abstract Background Dalbavancin is approved for the treatment of acute bacterial skin and soft structure infections (ABSSSI). There is less data on outcomes of off-label use of dalbavancin for orthopedic and other complex infections. In this case series, we aim to analyze clinical outcomes of deep-seated infections treated with IV dalbavancin instead of long-term IV antibiotics post-discharge. Methods We conducted a retrospective review of adult patients treated with off-label IV dalbavancin between January 2020 and February 2022 at an academic center in the Bronx, NY within a long-standing outpatient parenteral antibiotic therapy (OPAT) program. Outcomes of interest included 90-d infection recurrence, prothesis retention, mortality, adverse events, and characteristics of antibiotic regimens. Results Nineteen patients received dalbavancin for off-label indications. Dalbavancin was used primarily for hardware, bone and joint, and complicated soft tissue infections (table 1). The predominant pathogen was Staphylococcus aureus. Source control was achieved in 12 (63%) patients via debridement alone (5), debridement with prosthetic device retention (4), or debridement and complete hardware removal (3). The most common dosing regimen was two-doses (1000-mg, 500-mg) one week apart. Two (11%) patients (both with initial prosthesis retention) had infection recurrence within 90 days of dalbavancin and eventually required removal (table 2). One patient experienced recurrence after 90 days and required removal. The remaining patient with prothesis retention has not experienced infection recurrence to date. Concomitant antibiotics while on dalbavancin and suppressive antibiotics following therapy were common. No patient died within 90 days of therapy and no adverse drug effects were reported. Conclusion Dalbavancin use for hardware infections, osteomyelitis, complicated soft tissue infections, and spinal infections is associated with favorable cure rates, safety profile, and tolerability. Improved outcomes may be achieved with hardware removal. Dalbavancin off-label use within an OPAT program may facilitate early discharge or prevent admissions in eligible patients, although further study is needed. Disclosures All Authors: No reported disclosures.