Antibiotic Suppression Research Articles

The gut microbiota prime systemic antiviral immunity via the cGAS-STING-IFN-I axis

The microbiota are vital for immune homeostasis and provide a competitive barrier to bacterial and fungal pathogens. Here, we investigated how gut commensals modulate systemic immunity and response to viral infection. Antibiotic suppression of the gut microbiota reduced systemic tonic type I interferon (IFN-I) and antiviral priming. The microbiota-driven tonic IFN-I-response was dependent on cGAS-STING but not on TLR signaling or direct host-bacteria interactions. Instead, membrane vesicles (MVs) from extracellular bacteria activated the cGAS-STING-IFN-I axis by delivering bacterial DNA into distal host cells. DNA-containing MVs from the gut microbiota were found in circulation and promoted the clearance of both DNA (herpes simplex virus type 1) and RNA (vesicular stomatitis virus) viruses in a cGAS-dependent manner. In summary, this study establishes an important role for the microbiota in peripheral cGAS-STING activation, which promotes host resistance to systemic viral infections. Moreover, it uncovers an underappreciated risk of antibiotic use during viral infections.

MP02-16 LONG-TERM OUTCOMES AFTER ELECTROFULGURATION FOR ANTIBIOTIC-REFRACTORY RECURRENT URINARY TRACT INFECTIONS

You have accessJournal of UrologyCME1 May 2022MP02-16 LONG-TERM OUTCOMES AFTER ELECTROFULGURATION FOR ANTIBIOTIC-REFRACTORY RECURRENT URINARY TRACT INFECTIONS Shivani Gaitonde, Alana L. Christie, and Philippe E. Zimmern Shivani GaitondeShivani Gaitonde More articles by this author , Alana L. ChristieAlana L. Christie More articles by this author , and Philippe E. ZimmernPhilippe E. Zimmern More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002514.16AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Antibiotic-refractory recurrent urinary tract infections (rUTI) are challenging to manage. Prior studies have shown that in well-selected patients, electrofulguration (EF) of chronic trigonitis may disrupt a potential nidus of rUTI [1,2]. We report on long-term outcomes for women with at least five years of follow-up after EF. METHODS: Following IRB approval, we analyzed a cohort of non-neurogenic women with >3 symptomatic UTI/yr and cystoscopic evidence of trigonitis, who underwent EF from 2006 to 2011. Those with alternate identifiable source of rUTI (upper tract, prior mesh, stage 2 prolapse) or less than 5yr follow-up were excluded. Preoperative characteristics (demographics, antibiotic regimens, UTI/yr) were reported. The primary outcomes at 5yr post-EF were clinical cure (0-1 UTI/yr), improvement (2/yr) or unchanged (>3/yr), and endoscopic cure (no lesions on cystoscopy), improvement (persistent trigonitis), or progression (lesions beyond the trigone). Secondary outcomes were need for antibiotics prophylaxis or repeat EF. RESULTS: Of 44 women, median age was 65yr (56-74), parity was 2 (1-3), and BMI was 24.2 (20.7-29.3). Mean follow-up was 117 months (60-180); 22 women had >10yr follow-up. Prior to EF, 80% used daily antibiotic suppression, 9% used post-coital prophylaxis, and 14% used additional self-start therapy if symptomatic. 6 patients required IV antibiotics for pyelonephritis or multidrug resistance. By 5yr post-EF, 57% were clinically cured, 32% were improved, and 11% were unchanged. 86% had endoscopic cure, 7% had improvement and 7% had progression. 45% of all women did not need any antibiotic regimen, 35% used self-start therapy as needed, 18% used daily prophylaxis, and 9% used post-coital prophylaxis. All clinically cured patients also had endoscopic cure, and 79% did not use any antibiotic therapy. In contrast, both improved and unchanged patients were more likely to continue post-EF prophylaxis (p<0.05) and have endoscopic persistence or progression (p<0.05). 80% of clinically unchanged patients underwent repeat EF; median time to repeat EF was 12 months (6-58). CONCLUSIONS: In women with over 5yr follow-up after EF for antibiotic-refractory rUTI and trigonitis, there appears to be durable clinical cure and improvement, with decreased need for long-term antibiotics.

Long-term survival of fully cemented stem in re-revision total knee arthroplasty performed on femur with diaphyseal deformation due to implant loosening

The study aims to analyze long-term clinical and radiographic results, and survival of re-revision total knee arthroplasty (TKA) using fully cemented stems performed on femurs with diaphyseal deformation. Thirty-seven re-revision TKAs using fully cemented stems performed in femoral diaphyseal deformations, characterized as diaphyseal canal enlargement and cortex deformation due to aseptic loosening of previously implanted stems, between 2003 and 2015 were retrospectively reviewed. The mean follow-up period was 10.0years. Clinically, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and range of motion (ROM) were evaluated. Radiographically, mechanical axis (MA) and component positions were measured. Complications and survival rates were also analyzed. Clinically, the WOMAC significantly improved at final follow-up (61.2 vs 47.2, p < 0.001), but not the ROM (95.5 vs 102.5, p = 0.206). Radiographically, the MA and component positions were appropriate, with no changes in component positions from immediately post-operative to final follow-up, but with MA change from varus 2.9° to 3.7° (p = 0.020). Two cases (5.4%) with history of previous infections developed periprosthetic joint infection (PJI). Debridement with polyethylene insert exchange following antibiotic suppression were performed in those cases because of concern for difficult implant-cement removal. The fiveand tenyear survival rates were 100% and 93.2%, respectively. Fully cemented stems are viable in providing long-term satisfactory survival after re-revision TKA in patients with femoral diaphyseal deformation. However, it should be used carefully for those with previous infections.

Outcomes of Concurrent Endocarditis and Periprosthetic Joint Infection: A Retrospective Case Series of 16 Patients.

IntroductionConcurrent diagnosis of periprosthetic joint infection (PJI) of total hip arthroplasty (THA) or total knee arthroplasty (TKA) with infectious endocarditis is a devastating clinical scenario infrequently documented in the literature. To date, no studies have fully described the orthopedic and infectious outcomes of patients with these concurrent diagnoses. The purpose of this study was to conduct a case series of patients with these diagnoses and document the orthopedic and infectious outcomes so that surgeons may effectively counsel patients regarding the gravity of the condition and the expected course of treatment.MethodsThis study is a retrospective case series using patient data from five hospitals within an academic healthcare system in the northeastern United States. Cases of concurrent endocarditis and THA or TKA PJI with a minimum of one-year follow-up were identified from January 2000 to January 2021. Basic statistics such as means, standard deviations, and percentages were used to identify trends within our series. Kaplan-Meier survivorship curves with log-rank tests were performed to determine if there were any differences in two-year mortality and joint survival (defined as needing explant) between patients who had cardiac surgery prior to surgical management for their PJI and those who had surgical management for PJI prior to cardiac surgery.ResultsA total of 18 joints in 16 patients with endocarditis and concurrent TKA or THA PJI were identified. All PJIs were managed surgically, with 14/18 (77.77%) of joint infections initially being managed by debridement, antibiotics, and implant retention (DAIR) and 4/18 (22.22%) of joint infections initially being managed by explant. Within the first six months of PJI diagnosis, 25% (4/16) of patients died of complications related to their infection, and one additional patient died of bacteremia just over a year after the initial PJI diagnosis. Of the 18 PJIs, 72.23% (13/18) had treatment failure, defined as any outcome equal to or worse than requiring chronic suppressive antibiotics for the infection. Due to low statistical power, we were not able to identify any differences in two-year mortality from PJI diagnosis (p=0.311) or joint survival (in terms of requiring explant) (p=0.420) depending on whether cardiac surgery or DAIR was performed first.ConclusionsConcurrent infectious endocarditis and prosthetic joint infection is associated with high morbidity and mortality. Patients with these concurrent infections should be counseled that not only the associated mortality rate is high, but also the surgical treatment of their PJI has a high rate of treatment failure, including an explant following an initial DAIR, an explant with retained spacer, or a requirement of lifelong antibiotic suppression.

Isothermal Microcalorimetry Improves the Time to Diagnosis of Fracture-related Infection Compared With Conventional Tissue Cultures.

Isothermal Microcalorimetry Improves the Time to Diagnosis of Fracture-related Infection Compared With Conventional Tissue Cultures.

The presence of a draining sinus is associated with failure of re-implantation during two-stage exchange arthroplasty.

Background: Reinfection rates after two-stage exchange arthroplasty for prosthetic joint infection (PJI) have been reported as high as 33 % in the literature. Understanding risk factors for treatment failure will help to preoperatively counsel patients on the likelihood of successful treatment and possibly influence the surgeon's treatment algorithm. This study aimed to delineate whether the presence of a draining sinus tract is associated with risk of failure of two-stage exchange arthroplasty. Methods: We performed a single institution, multi-center retrospective chart review of outcomes of patients treated for PJI with two-stage exchange arthroplasty between June 2006 and May 2016. For patients treated prior to 2011, PJI was defined based on the preoperative work-up and intraoperative findings as determined by the attending surgeon. After 2011, PJI was defined using MSIS consensus criteria. All patients had a minimum of follow-up of 2 years or treatment failure prior to 2 years. Treatment failure was defined as reinfection or failure to complete two-stage exchange secondary to persistent infection or other host factors. Operative reports and clinical notes were reviewed to assess for presence of a draining sinus tract. Results: 240 patients were treated for PJI with intended two-stage exchange arthroplasty. The overall rate of treatment failure was 29.6 % (), while the overall rate of reinfection was 13.3 % (). A total of 39 patients did not complete second stage revision; final treatment for these patients was amputation, fusion, or chronic antibiotic suppression. A total of 52 of 240 patients (21.7 %) had a draining sinus tract at presentation. Patients with a sinus tract were significantly less likely to be replanted compared to those without a sinus tract at presentation (13.3 % vs. 26.9 %, ). However, when accounting for all mechanisms of treatment failure, including reinfection following replantation, there was no statistically significant difference detected between the sinus and no-sinus groups (27.7 % vs. 36.5 %, ). Discussion: A draining sinus tract represents a chronic, deep infectious process with ultimate compromise of overlying soft tissues. Thus we hypothesized it would be associated with failure in a two-stage exchange arthroplasty. These data demonstrate that patients with a draining sinus are significantly less likely to undergo re-implantation. This provides evidence to the paucity of data surrounding draining sinuses and two-stage PJI treatment.

Reconstruction with a cage outlives patients with metastatic disease involving the acetabulum.

The aim of this study was to determine whether patients treated with a caged reconstruction for metastatic acetabular disease would have a construct survival superior to that of their life expectancy. We undertook a retrospective study, in a single centre in the United Kingdom, reviewing outcomes for 19 patients (20 hips) treated with a cage reconstruction for metastatic disease of their acetabulum over 6 years. Inclusion criteria were those with an impending fracture of the acetabulum, metastatic dissociation, fracture of the acetabulum and or femur and those whose life expectancy was considered by the oncology team to be >6 months. In all patients the Restoration GAP II acetabular cage (Stryker, Howmedica Osteonics Corp, NJ, USA) was used in conjunction with a cemented acetabular cup and cemented femoral stem. The mean age at the time of surgery was 68 (44-87) years with breast cancer being the most common primary malignancy (31%) followed by prostate cancer (26%).Radiological survivorship estimates were 94.1% (95% CI, 99.2-65.0) at 12 and 24 months, 70.6% (95% CI, 93.6-16.0) at 36 months and 35.3% (95% CI, 78.2-1.2) at 48 months. There were 3 radiological failures of the implant due to disease progression. Complications occurred in 3 patients with 2 developing deep infection which was treated with suppressive antibiotic therapy following aspiration of the hip. 1 patient suffered a hip dislocation following trauma which was successfully reduced closed and no further intervention was required. This study represents the first published case series of the use of the GAP II cage in patients with metastatic acetabular disease. The construct generally outlives the patient and hence is suitable for the treatment of acetabular metastases.

Driveline Infection in Left Ventricular Assist Device Patients: Effect of Standardized Protocols, Pathogen Type, and Treatment Strategy.

Driveline infection (DLI) is common after left ventricular assist device (LVAD). Limited data exist on DLI prevention and management. We investigated the impact of standardized driveline care initiatives, specific pathogens, and chronic antibiotic suppression (CAS) on DLI outcomes. 591 LVAD patients were retrospectively categorized based on driveline care initiatives implemented at our institution (2009-2019). Era (E)1: nonstandardized care; E2: standardized driveline care protocol; E3: addition of marking driveline exit site; E4: addition of "no shower" policy. 87(15%) patients developed DLI at a median (IQR) of 403(520) days. S. aureus and P. aeruginosa were the most common pathogens. 31 (36%) of DLI patients required incision and drainage (I&D) and 5 (5.7%) device exchange. P. aeruginosa significantly increased risk for initial I&D (HR 2.7, 95% CI, 1.1-6.3) and recurrent I&D or death (HR 4.2, 95% CI, 1.4-12.5). Initial I&D was associated with a significant increased risk of death (HR 2.92 (1.33-6.44); P = 0.008) when compared to patients who did not develop DLI. Implementation of standardized driveline care protocol (E2) was associated with increased 2-year freedom from DLI compared to nonstandardized care (HR 0.36, 95% CI, 0.2-0.6, P < 0.01). Additional preventive strategies (E3&E4) showed no further reduction in DLI rates. 57(65%) DLI patients received CAS, 44% of them required escalation to intravenous antibiotics and/or I&D. Presence of P. aeruginosa DLI markedly increased risk for I&D or death. Conditional survival of patients progressing to I&D is diminished. Standardized driveline care protocol was associated with a significant reduction in DLI, while additional preventive strategies require further testing.

Minimizing Antibiotic Use in Urethral Reconstruction.

There are no established guidelines regarding management of antibiotics for patients specifically undergoing urethral reconstruction. Our aim was to minimize antibiotic use by following a standardized protocol in the pre-, peri- and postoperative setting, and adhere to American Urological Association antibiotic guidelines. We hypothesized that prolonged suppressive antibiotics post-urethroplasty does not prevent urinary tract infection and/or wound infection rates. We prospectively treated 900 patients undergoing urethroplasty or perineal urethrostomy at 11 centers over 2 years. The first-year cohort A received prolonged postoperative antibiotics. Year 2, cohort B, did not receive prolonged antibiotics. A standardized protocol following the American Urological Association guidelines for perioperative antibiotics was used. The 30-day postoperative infectious complications were determined. We used chi-square analysis to compare the cohorts, and multivariate logistic regression to identify risk factors. The mean age of participants in both cohorts was 49.7 years old and the average stricture length was 4.09 cm. Overall, the rate of postoperative urinary tract infection and wound infection within 30 days was 5.1% (6.7% in phase 1 vs 3.9% in phase 2, p=0.064) and 3.9% (4.1% in phase 1 vs 3.7% in phase 2, p=0.772), respectively. Multivariate logistic regression analysis of patient characteristics and operative factors did not reveal any factors predictive of postoperative infections. The use of a standardized protocol minimized antibiotic use and demonstrated no benefit to prolonged antibiotic use. There were no identifiable risk factors when considering surgical characteristics. Given the concern of antibiotic over-prescription, we do not recommend prolonged antibiotic use after urethral reconstruction.

Predictors of Success With Chronic Antibiotic Suppression for Prosthetic Joint Infections

BackgroundManagement of recurrent prosthetic joint infection (PJI) after attempted surgical eradication remains a challenge. Chronic antibiotic suppression (CAS) is regarded as a reasonable treatment option for select patients with persistent infection or multiple comorbidities. The study seeks to compare cohorts who succeed and fail with CAS. MethodsThis retrospective cohort study assesses patients who were treated with CAS for a PJI. Patients were included if they had a culture-proven PJI and received chronic suppressive antibiotics. Failure of suppression was defined as reoperation after initiating CAS or death occurring as result of infection. A Cox proportional hazards multivariate regression model was used to estimate risk of reoperation as a function of risk factors related to patient comorbidities, surgical history, affected joint, and infecting organism. ResultsWe identified 45 PJIs (31 knees, 14 hips) managed with CAS with a median follow-up of 50 (95% confidence interval [CI] 33.61-74.02) months. The overall success rate of managing PJI with CAS was 67% (30/45). Controlling for body mass index and Gram status of the organism, total hip arthroplasty patients were less likely than total knee arthroplasty patients to require reoperation (hazard ratio 0.18, 95% CI 0.01-0.96, P = .04). Patients with Gram-positive infections were less likely than those with a Gram-negative infections to require reoperation (hazard ratio 0.22, 95% CI 0.05-0.88, P = .03). Severe antibiotic side effects were rare. Patients who experienced multiple changes to their antibiotic regimen were more likely to fail with CAS. ConclusionCAS is a reasonable strategy in patients with PJI who lack or refuse further surgical treatment options. Most hips and Gram-positive infections treated with CAS successfully avoided reoperation in this cohort.

Medicosurgical management of deep wound infections after thoracolumbar instrumentation: risk factors of poor outcomes.

Surgical site infection (SSI) after thoracolumbar osteosynthesis is a common complication. Its management relies on surgical revision and antibiotic therapy, but treatment failure is not uncommon. The aim of our study was to assess the frequency of SSI management failure and its risk factors. A retrospective study of patients hospitalized from 2011 to 2019 at the University Hospital of Caen was carried out. The infection rate and the time to onset of failure were assessed over a minimum follow-up of 1year. Treatment failure was defined as the occurrence of a new intervention in the spine in the year following the end of antibiotic therapy, the establishment of long-term suppressive antibiotic therapy, or death from any cause within 1year of the end of antibiotic therapy. We compared the treatment failure group with the treatment success group to determine risk factors for treatment failure. A total of 2881 patients underwent surgery during the study period, and 92 developed an SSI, corresponding to an SSI rate of 3.19%. Thirty-six percent of the patients with an SSI presented treatment failure. The median time to failure was 31days. On multivariate analysis, diabetes mellitus was identified as a risk factor for treatment failure, whereas prolonged postoperative drainage for 4 to 5days was a protective factor. The number of failures was significant, and failure occurred mainly during the early phase. To decrease the risk of treatment failure, prolonged duration of postoperative drainage seems to be helpful. Additionally, as diabetes is a risk factor for treatment failure, good control of glycemia in these patients might impact their outcomes.

Results of 'two-in-one' single-stage revision total knee arthroplasty for infection with associated bone loss : prospective five-year follow up.

AimsPeriprosthetic joint infection (PJI) occurs in approximately 1% to 2% of total knee arthroplasties (TKA) presenting multiple challenges, such as difficulty in diagnosis, technical complexity, and financial costs. Two-stage exchange is the gold standard for treating PJI but emerging evidence suggests 'two-in-one' single-stage revision as an alternative, delivering comparable outcomes, reduced morbidity, and cost-effectiveness. This study investigates five-year results of modified single-stage revision for treatment of PJI following TKA with bone loss.MethodsPatients were identified from prospective data on all TKA patients with PJI following the primary procedure. Inclusion criteria were: revision for PJI with bone loss requiring reconstruction, and a minimum five years’ follow-up. Patients were followed up for recurrent infection and assessment of function. Tools used to assess function were Oxford Knee Score (OKS) and American Knee Society Score (AKSS).ResultsA total of 24 patients were included with a mean age of 72.7 years (SD 7.6), mean BMI of 33.3 kg/m2 (SD 5.7), and median ASA grade of 2 (interquartile range 2 to 4). Mean time from primary to revision was 3.0 years (10 months to 8.3 years). At revision, six patients had discharging sinus and three patients had negative cultures from tissue samples or aspirates. Two patients developed recurrence of infection: one was treated successfully with antibiotic suppression and one underwent debridement, antibiotics, and implant retention. Mean AKSS scores at two years showed significant improvement from baseline (27.1 (SD 10.2 ) vs 80.3 (SD 14.8); p < 0.001). There was no significant change in mean AKSS scores between two and five years (80.3 (SD 14.8 ) vs 74.1 (SD 19.8); p = 0.109). Five-year OKS scores were not significantly different compared to two-year scores (36.17 (SD 3.7) vs 33.0 (SD 8.5); p = 0.081).Conclusion‘Two-in-one’ single-stage revision is effective for treating PJI following TKA with bone loss, providing patients with sustained improvements in outcomes and infection clearance up to five years post-procedure.Cite this article: Bone Jt Open 2022;3(2):107–113.

Local antibiotic treatment with calcium sulfate as carrier material improves the outcome of debridement, antibiotics, and implant retention procedures for periprosthetic joint infections after hip arthroplasty - a retrospective study.

Purpose: Debridement, antibiotics, and implant retention (DAIR) is an established treatment modality in periprosthetic joint infections (PJIs), but success rates vary. This study compared the success of DAIR for PJIs after a total hip arthroplasty (THA), with or without local antibiotic delivery with CaSO as the carrier material. Methods: A retrospective review of DAIR for PJIs after THA performed between 2010 and 2018, including 41 patients is conducted. A total of 27 patients were treated by DAIR with local antibiotics with CaSO as the carrier material, and 14 patients were treated by a standard DAIR. The endpoints were treatment failure, defined as the need for a reoperation, either a second DAIR or a prosthesis removal or exchange due to persistent or recurrent infection, the initiation of a long-term suppressive antibiotic treatment, or death related to infection. Results: Considering any reoperation as an outcome, 11 of 14 cases treated without AB-CaSO (79 %) and 4 of the 27 cases treated with AB-CaSO failed (15 %). Considering revision as an outcome, 9 out of 14 cases treated without AB-CaSO (64 %) and 4 of the 27 cases treated with AB-CaSO (15 %) failed. A Kaplan–Meier survival analysis showed that local antibiotic delivery with CaSO as the carrier material led to a significantly longer infection-free survival, considering any surgical revision (; hazard ratio 8.9 (95 % CI 2.8–28.2)) or revision with component exchange (; hazard ratio 5.6 (95 % CI 1.7–18.2)) as the endpoint. Conclusion: The addition of local antibiotics with CaSO as the carrier material to DAIR for PJIs after THA significantly increases success rates, such as infection-free survival, any reoperation, and revision with component exchange in particular.

Allograft Vesicoureteral Reflux after Kidney Transplantation.

Allograft vesicoureteral reflux (VUR) is a leading urological complication of kidney transplantation. Despite the relatively high incidence, there is a lack of consensus regarding VUR risk factors, impact on renal function, and management. Dialysis vintage and atrophic bladder have been recognized as the most relevant recipient-related determinants of post-transplant VUR, whilst possible relationships with sex, age, and ureteral implantation technique remain debated. Clinical manifestations vary from an asymptomatic condition to persistent or recurrent urinary tract infections (UTIs). Voiding cystourethrography is widely accepted as the gold standard diagnostic modality, and the reflux is generally graded following the International Reflux Study Committee Scale. Long-term transplant outcomes of recipients with asymptomatic grade I-III VUR are yet to be clarified. On the contrary, available data suggest that symptomatic grade IV-V VUR may lead to progressive allograft dysfunction and premature transplant loss. Therapeutic options include watchful waiting, prolonged antibiotic suppression, sub-mucosal endoscopic injection of dextranomer/hyaluronic acid copolymer at the site of the ureteral anastomosis, and surgery. Indication for specific treatments depends on recipient’s characteristics (age, frailty, compliance with antibiotics), renal function (serum creatinine concentration < 2.5 vs. ≥ 2.5 mg/dL), severity of UTIs, and VUR grading (grade I-III vs. IV-V). Current evidence supporting surgical referral over more conservative strategies is weak. Therefore, a tailored approach should be preferred. Properly designed studies, with adequate sample size and follow-up, are warranted to clarify those unresolved issues.

Successive new-pathogen prosthetic joint reinfections: Observational cohort study on 61 patients.

Prosthetic joint infection (PJI) treatment failure may be due to relapsing infection (same microorganism) or new-pathogen reinfection (npPJI). The aim was to describe npPJI epidemiological, clinical and microbiological characteristics, their treatments and outcomes, and identify their risk factors. This observational, single-center, cohort study was conducted in a French Referral Center for Bone-and-Joint Infections between September 2004 and December 2015. Patients treated for at least two successive hip or knee PJIs in the same joint with a different pathogen were identified in the prospective database. We compared each patient's first PJI and subsequent npPJI(s) to analyze the type and microbiological characteristics of npPJIs. To search for npPJI risk factors, we compared those cases to a random selection of 122 "unique-episode" PJIs treated during the study period. Among 990 PJIs, 79 (8%) npPJIs occurring in 61 patients were included. New-pathogen prosthetic joint infections (npPJIs) developed more frequently in knee (14%) than hip prostheses (5%). Median interval from the first PJI to the npPJI was 26 months. New-pathogen prosthetic joint reinfections (npPJIs) more frequently spread hematogenously (60% vs 33%) and were predominantly caused by Staphylococcus (36%) or Streptococcus (33%) species. Multivariate analysis identified two risk factors: chronic dermatitis (odds ratio: 6.23; P<0.05) and cardiovascular diseases (odds ratio: 2.71; P<0.01). A curative strategy was applied to 70%: DAIR (29%), one-stage (28%), two-stage exchange arthroplasty (7%) or other strategies (7%). The others received prolonged suppressive antibiotic therapy (30%). New-pathogen prosthetic joint infections (npPJIs) are complex infections requiring management by multidisciplinary teams that should be adapted to each clinical situation.

Case Series of the Management of Surgical Site Infection following Thoracic Spinal Surgeries during COVID Pandemic

Introduction: Post-operative spinal wound infection increases the morbidity of the patient and the cost of healthcare. Despite the development of prophylactic antibiotics and advances in surgical technique and post-operative care, wound infection continues to compromise patient outcome after spinal surgery. This kind of infection places the patient at risk for pseudoarthrosis, adverse neurologic sequelae, chronic pain, deformity, and even death. In spite of all preventive measures, the SSI following spinal surgeries are 1% among operated spinal instrumentation. Case Series: Here, we present a series of three patients who presented to us with post-operative surgical site infection (SSI) in spine surgery in the form of wound, discharge, and other complaints. Out of all, two of them were operated with debridement and skin closure followed by broad spectrum IV antibiotics and one of them managed with vacuum-assisted closure dressing and high antibiotics sensitive to organisms found in wound culture. Optimization by building up hemoglobin, supplementing micronutrients including Vitamin C, D, and B12 and high protein diet was started as adjuvant therapy and all of them was discharged with healthy wound. Conclusion: SSI in spine surgery is a common but challenging complication, particularly after instrumental spinal arthrodesis. Using meticulous aseptic technique, intra-operative irrigation, prophylactic antibiotics, and optimizing patient factors preoperatively are key to preventing a SSI. In patients who still develop an infection despite efforts at prevention, timely diagnosis and treatment are critical. Instrumentation can be retained while still successfully clearing an early infection, although following fusion, instrumentation can be removed if lifetime oral antibiotic suppression is either not indicated or undesirable. Keywords: Spine surgery, Postoperative infections, Surgical site infection, Spinal instrumentation.

252. Joint Decisions: Optimal Duration of Chronic Suppressive Antibiotics in Adults with Prosthetic Joint Infections Who Underwent Debridement, Antibiotics, Irrigation, and Retention of Prostheses

Abstract Background Hip and knee arthroplasties are associated with complications including prosthetic joint infections (PJI). Management ranges from explantation to debridement, antibiotics, irrigation, and retention of prostheses (DAIR). In DAIR, patients receive intravenous antibiotics followed by chronic suppressive antibiotics. Current guidelines on suppressive antibiotic use after DAIR are unclear and based on expert consensus. This study seeks to elucidate the optimal duration of chronic suppressive antibiotics after DAIR. Methods This is a retrospective cohort study of adults in the Southern California Kaiser Permanente System with hip and knee prosthetic joint infections who underwent DAIR from 2007-2017. Culture data and durations of suppressive antibiotics were collected and patients were followed for 1 year after completion. Treatment failure was determined by mortality, re-infection, or prosthesis removal. Patients who received no antibiotics vs. less than 3 months vs 3 to 6 months vs greater than 1 year were compared. Results 350 charts were reviewed and 145 patients were included. There were 87 knee and 58 hip PJIs with 32 patients (22%) who failed treatment. There were more cases of failure when patients didn’t receive suppressive antibiotics (27%) vs those who received any (19%), however the results were not significant. There were no significant differences in failure rates between short vs longer suppressive antibiotic courses regardless of the duration (Staph vs non-Staph, hip vs knee). Patients with Staphyloccocal infections and knee infections were significantly more likely to fail treatment (p=0.0196 &amp; 0.0150, logistic regression). Conclusion This study shows the importance of suppression with oral antibiotics after PJIs are treated with DAIR. The lack of difference in treatment failure between the durations of suppressive antibiotics makes it prudent to consider shorter courses of antibiotics, while placing attention on patients with knee and Staphylococcal infections as they are more likely to fail treatment. Limitations include sample size, difficulty in quantifying extent of initial infection and debridement, and provider dependent prolonging of antibiotic duration. Disclosures All Authors: No reported disclosures

94. Infectious Complications of Left Ventricular Assist Devices

BackgroundLeft ventricular assist devices (VAD) have significantly increased survival for patients with advanced heart failure. While advancements in devices during the past 10 years have improved thrombotic and bleeding complications, infection remains a significant cause of morbidity and mortality. We assessed the incidence and risk factors of VAD infections at our institution.MethodsA single center, retrospective study of patients who had VAD implanted between January 2007 and December 2020 was performed. Patients with concurrent right sided mechanical circulatory support devices were excluded. Patient demographics, clinical characteristics, labs, microbiology data, and antimicrobials were obtained from the electronic medical records. Clinical outcomes were adjudicated by 2 independent physicians. VAD infections were classified using the ISHLT 2011 guidelines.Results241 patients had durable VAD implanted in this 14-year period, with a median time of 3 years follow-up. 134 (56%) patients had a clinically significant infection; 42 (31.3%) were VAD specific infections, 42 (31.3%) were VAD related, and 50 (37.4%) were non-VAD related. 95% of VAD specific infections were driveline site infections. 98% of patients with VAD related infections had a concurrent blood stream infection. Of the 50 non-VAD infections, 72% involved either a lower respiratory, urinary tract, or Clostridium difficile infection. Median time from VAD implantation to infection was 5 months. 44 (32.8%) had their first infection during the index hospitalization, of which 27 (61.4%) were non-VAD infections. 78 (58.2%) had one infection, compared with 38 (28.4%) who had two or more infections. 17 (12.7%) had recurrence of their initial infection and 6 (35%) occurred despite being on suppressive antibiotics. 48 of 134 (36%) infected patients were transplanted. 57 of 134 (42.5%) died compared to 33 of 107 (31%) without an infection. ConclusionMore than half of VAD patients at our center during a 14-year time period had an infectious complication and higher mortality rate compared to those without an infectious complication. Further studies are needed to assess the immunologic risk factors for the increased risk of non-device associated infections in VAD patients.Disclosures Mandeep R. Mehra, MD, Abbott (Consultant)Baim Institute for Clinical Research (Consultant)FineHeart (Consultant)NupulseCV (Consultant) Ann E. Woolley, MD, MPH, COVAX (Consultant)

183. Management of Left Ventricular Assist Device Infections at a Large Academic Medical Center

Abstract Background Left ventricular assist device infections (LVADIs) contribute significantly to morbidity and mortality. The lack of evidenced-based treatment recommendations results in substantial variability in clinical practice. The purpose of this study was to evaluate the management of LVADIs at our institution to better assess practice patterns and standardize treatment decisions. Methods This was a retrospective study including adults diagnosed with an initial LVADI from January 1, 2013 to July 1, 2019. Exclusion criteria included concomitant non-LVADI, patients with other mechanical circulatory systems, or pregnancy. Pertinent patient, LVAD, infection, management, and clinical outcome data was collected and described with descriptive statistics. Results A total of 49 patients were included, 37 of which had at least one recurrence, resulting in 57 recurrent and 106 total LVADIs. The majority of LVADIs were driveline infections (DLIs) (92%). There was an increase in the incidence of deep DLIs (35% vs. 10%) and bloodstream infections (26% vs. 4%) amongst recurrent vs. initial LVADIs. Staphylococcus aureus (51%) and nosocomial gram-negatives (20%) were the most common causative pathogens. Surgical interventions were common (55%). LVADIs treated predominately with oral antibiotics (54%) or IV antibiotics (46%) received a median duration of therapy of 31 and 35 days, respectively. Antibiotic regimens included anti-methicillin-resistant S.aureus coverage and anti-pseudomonal coverage in 49% and 22% of total cases, respectively. Suppressive antibiotics were commonly prescribed (54%). LVADI-related readmission (69%) and recurrence (76%) within one year of initial LVADI was frequent. Recurrent LVADI occurred regardless of receiving suppressive therapy in 60% of total recurrent cases. Conclusion This study offers unique insight into initial vs. recurrent LVADIs as well as infection characteristics and clinical outcomes at a large academic medical center. Future studies with additional focus on risk factors for recurrence would be beneficial for drawing conclusions on the efficacy of current practices and shaping future treatment guidelines. Disclosures All Authors: No reported disclosures

92. Characteristics and Outcomes of Deep Brain Stimulation Device Related Infections: Experience from Quaternary Centers

BackgroundIncreasing use of deep brain stimulation (DBS) over the past 20 years is paralleled by a rise in DBS infections. There is a paucity of data on the diagnosis, management, and outcomes in such infections. We describe our center’s experience with DBS infections. MethodsAdults ( >18 years) diagnosed with DBS associated infection between January 1, 2000 and May 1, 2020 were retrospectively reviewed. Data on patient demographics, clinical presentation, microbiology, and management was collected. ResultsSeventy cases were identified (table 1). The mean age at diagnosis was 58.9 ± 16.5 years. The bulk were free of comorbidities. Parkinson’s disease and essential tremors were the most common indications for DBS placement. The median time from implantation to infection was 4 months [IQR 1,24]. The neurotransmitter and extension wires were the most frequently infected parts. A microbiological diagnosis was made in 89% of cases, 47% of which were polymicrobial. The most commonly identified organisms were Staphylococcus aureus, Cutibacterium acnes, and coagulase-negative staphylococci. For patients with deep infection, 71% had complete device extraction, 20% partial extraction, and 9% device retention; clinical cure at 3 months occurred in 97%, 64% and 100%, respectively (figure 1). On the other hand, 93% of patients with superficial infection had device retention; cure at 3 months was seen in 64% (figure 2). Suppressive oral antibiotics were rarely used, 45% of patients with partial extraction and 26% with device retention. DBS was reimplanted in 71% of patients after complete extraction and led to reinfection in 30% at 1 year follow up. Median time to reimplantation was 2.7 months. All patients who failed at 3 months in the partial extraction and device retention cohorts subsequently underwent complete device removal leading to clinical cure sustained at 1 year follow up. ConclusionAll patients who had complete extraction achieved clinical cure at 3-months follow-up, while high failure rates occurred in those with device retention. Most infections were polymicrobial and predominantly caused by gram-positive pathogens. Thirty percent of patients with re-implantation after complete device extraction developed re-infection within 1 year. Disclosures All Authors: No reported disclosures