High Frequency of Low-Virulent Microorganisms Detected by Sonication of Implanted Pulse Generators: So What?

INTRODUCTION: Deep brain stimulation (DBS) has become a well-established treatment modality for a variety of conditions over the last decades. Multiple surgeries are an essential part in the postoperative course of DBS patients if nonrechargeable implanted pulse generators (IPGs) are applied. So far, the rate of subclinical infections in this field is unknown. In this prospective cohort study, we used sonication to evaluate possible microbial colonization of IPGs from replacement surgery. METHODS: All consecutive patients undergoing IPG replacement between May 1, 2019 and November 15, 2020 were evaluated. The removed hardware was investigated using sonication to detect biofilm-associated bacteria. Demographic and clinical data were analyzed. RESULTS: A total of 71 patients with a mean (±SD) of 64.5 ± 15.3 years were evaluated. In 23 of these (i.e., 32.4%) patients, a positive sonication culture was found. In total, 25 microorganisms were detected. The most common isolated microorganisms were Cutibacterium acnes (formerly known as Propionibacterium acnes) (68%) and coagulase-negative Staphylococci (28%). Within the follow-up period (5.2 ± 4.3 months), none of the patients developed a clinical manifest infection. DISCUSSIONS/CONCLUSIONS: Bacterial colonization of IPGs without clinical signs of infection is common but does not lead to manifest infection. Further larger studies are warranted to clarify the impact of low-virulent pathogens in clinically asymptomatic patients.

Detection of bacterial DNA on neurostimulation systems in patients without overt infection.

OBJECTIVE: Hardware-related infection remains a major problem in patients with neurostimulation systems. The role of bacterial colonization and the formation of biofilm on the surface of implanted devices remain unclear. Here, we analysed the incidence of bacterial DNA on the surface of implantable pulse generators (IPGs) using 16S rRNA gene sequencing in a consecutive series of patients who underwent routine IPG replacement without clinical signs of infection. PATIENTS AND METHODS: We included 36 patients who underwent scheduled replacement surgery of 44 IPGs. The removed IPGs were processed and whole genomic DNA was extracted. The detection of bacterial DNA was carried out by Polymerase Chain Reaction (PCR) using universal bacterial primers targeting the 16S rRNA gene. The DNA strands were analysed by single-strand conformation polymorphism (SSCP) analysis. RESULTS: Indications for chronic neurostimulation were Parkinson disease, tremor, dystonia, neuropathic pain and peripheral artery occlusion disease. Mean age of patients at the time of implantation was 48 ±â€¯17.6 years. The mean interval between implantation and replacement of the IPG was 24.8 months. PCR/SSCP detected bacterial DNA of various species in 5/36 patients (13.9%) and in 5/44 pacemakers (11.4%), respectively. There was no evidence of clinical infection or wound healing impairment during follow-up time of 45.6 ±â€¯19.6 months. CONCLUSION: Bacterial DNA can be detected on the surface of IPGs of neurostimulation systems in patients without clinical signs of infection by using PCR techniques. It remains unclear, similar to other permanently implanted devices, which mechanisms and processes promote progression to the point of overt infection.

Life-threatening DBS withdrawal syndrome in Parkinson's disease can be treated with early reimplantation.

INTRODUCTION: The deep brain stimulation (DBS) withdrawal syndrome (DBS-WDS) is a rare, life-threatening complication in Parkinson's disease (PD) patients with long disease duration and stimulation when stimulation is terminated for extended periods mostly due to infection of the DBS-hardware. METHODS, RESULTS: In five patients explantation became necessary because of infection after a mean of 11.4 years (range 4-15 years) of DBS and a mean disease duration of 24.6 years (range 3-22 years). Mean UPDRS motor-score pre-explantation was 38 points (range 24-55 points) which increased to a mean of 78.4 points (range 58-90 points) after explantation, despite optimal Levodopa dosing. Reimplantation of the hardware after 23 days (range 3-45 days) under antibiotic treatment led to an improvement to a mean of 40 points (range 25-73 points) and a complication free survival. CONCLUSION: Early reimplantation of the DBS-hardware is a treatment option of the DBS-WDS when the life-threatening urgency overrides surgical standards. Observation of the syndrome indicates pharmacological unresponsiveness of the dopaminergic system in advanced PD and long-term DBS.

Recommendations on nuclear and multimodality imaging in IE and CIED infections.

In the latest update of the European Society of Cardiology (ESC) guidelines for the management of infective endocarditis (IE), imaging is positioned at the centre of the diagnostic work-up so that an early and accurate diagnosis can be reached. Besides echocardiography, contrast-enhanced CT (ce-CT), radiolabelled leucocyte (white blood cell, WBC) SPECT/CT and [18F]FDG PET/CT are included as diagnostic tools in the diagnostic flow chart for IE. Following the clinical guidelines that provided a straightforward message on the role of multimodality imaging, we believe that it is highly relevant to produce specific recommendations on nuclear multimodality imaging in IE and cardiac implantable electronic device infections. In these procedural recommendations we therefore describe in detail the technical and practical aspects of WBC SPECT/CT and [18F]FDG PET/CT, including ce-CT acquisition protocols. We also discuss the advantages and limitations of each procedure, specific pitfalls when interpreting images, and the most important results from the literature, and also provide recommendations on the appropriate use of multimodality imaging.

The "Subtle" connection between development of cardiac implantable electrical device infection and survival after complete system removal: An observational prospective multicenter study.

BACKGROUND: Despite the improvements in transvenous lead extraction (TLE), patients with cardiac implantable device related infection (CIEDI) have a poor prognosis at long term. We explored the possible role of factors associated with development of CIEDI as predictors of post-TLE survival. METHODS: We performed a multi-center prospective observational study in a population of consecutive patients referred for TLE for CIEDI. We adopted a previously developed 10-point scale for CIEDI risk stratification and assessed its performance in predicting post-TLE survival. RESULTS: We enrolled 169 consecutive patients with CIEDI (systemic infection in 48.5% and vegetations in 24.5%). A Shariff score ≥3 was present in 102/169 (60.4%) of the enrolled patients. Complete radiological success of TLE was obtained in 163 patients. Twenty-seven patients (15.9%) died after a mean follow-up of 20.8±12.0months. Two factors were independently associated with post-TLE death: a Shariff score ≥3 (HR 10.833, 95% CI 2.544-46.129; p=0.001) and the presence of vegetations at transesophageal echocardiography (HR 3.324, 95% CI 1.530-7.221; p=0.002). CONCLUSIONS: Risk factors for development of CIEDI are also predictive of post TLE mortality, together with the presence of vegetations. Improvement of our preventive strategies for CIEDI is crucial for enhancing the outcomes of CIED patients overall.

Deep Brain Stimulation-Related Infections: Analysis of Rates, Timing, and Seasonality.

BACKGROUND: Infection is one of the most common complications of deep brain stimulation (DBS). Long-term infection rates beyond the immediate postoperative period are rarely evaluated. OBJECTIVE: To study short- and long-term DBS-related infection rates; to evaluate any potential seasonality associated with DBS-related infections. METHODS: We retrospectively reviewed all DBS surgeries performed in a 5-yr period at 1 hospital by a single surgeon. Infection rates and clinical characteristics were analyzed. Postoperative "infections" were defined as occurring within 6 mo of implantation of DBS hardware, while "erosions" were defined as transcutaneous exposure of hardware at ≥6 mo after implantation. Based on the date of surgery preceding an infection, rates of infection were calculated on a monthly and seasonal basis and compared using Chi square and logistic regression analyses. RESULTS: A total of 443 patients underwent 592 operations; 311 patients underwent primary DBS placement with 632 electrodes. Primary DBS placement infection incidence was 2.6%. DBS procedure infection and infection rate by electrode were 2.9% and 3.2%, respectively. Infectious complications presented later than 6 mo postoperatively in 38% of infected patients Summer (July-September) infection rate was significantly higher than other seasons (P = .002). The odds ratio of an infection related to a surgery performed in August was found to be 4.15 compared to other months (P = .021). CONCLUSION: There is a persistent risk of DBS infection and erosion beyond the first year of DBS implantation. Start of the academic year was associated with increased infection rate at our institution.

Systematic review of hardware-related complications of Deep Brain Stimulation: Do new indications pose an increased risk?

INTRODUCTION: Deep Brain Stimulation (DBS) is an effective treatment extended broadly to many neurological and psychiatric disorders. Nevertheless, complications may arise during DBS procedures or following implantation due to implanted hardware. This may result in both minor and major adverse events that may necessitate hardware removal and/or compromise maximal therapeutic benefit for the patient. OBJECTIVES AND METHODS: To identify relevant literature on hardware-related complications from DBS procedures by performing a systematic review, and propose how to identify at-risk group and possible preventive approaches. RESULTS: Of 4592 abstract screened, 96 articles fulfilled the selection criteria and were reviewed. Overall, the most common hardware-related complications were infections (5.12% of patients), followed by lead migration (1.60%), fracture or failure of the lead or other parts of the implant (1.46% and 0.73%, respectively), IPG malfunctions (1.06% of patients), and skin erosions without infections (0.48% of patients). New indications for DBS, including Tourette's syndrome, cluster headache, and refractory partial epilepsy, were found to bear a higher incidence of hardware-related infections than established indications such as Parkinson's disease. The highest rate of lead fracture or failure was found in dystonia patients (4.22%). Ultimately, the highest rate of pain at the implantation sites was found in refractory partial epilepsy patients (16.55%). CONCLUSION: Our analysis identified a variety of potential hardware-related complications among patients who underwent DBS procedures. Patients who were at risk of complications, such as patients with dystonia and off-label indications (e.g. Tourette's syndrome) should be informed prior to surgery and closely followed thereafter.

Spinal Cord Stimulator Implant Infection Rates and Risk Factors: A Multicenter Retrospective Study.

OBJECTIVES: Spinal cord stimulation is an evidence-based treatment for a number of chronic pain conditions. While this therapy offers improvement in pain and function it is not without potential complications. These complications include device failure, migration, loss of therapeutic paresthesia, and infection. This article looked to establish a modern infection rate for spinal cord stimulators, assess the impact of known risk factors for surgical site infections and to determine the impact of certain preventative measures on the rate of infection. METHODS: After institutional review board approval, a multisite, retrospective review was conducted on 2737 unique implants or revisions of SCS systems. Patient demographics, risk factors including diabetes, tobacco use, obesity, revision surgery, trial length, implant location, implant type, surgeon background, prophylactic antibiotic use, utilization of a occlusive dressing, and post-operative antibiotic use were recorded and analyzed. RESULTS: The overall infection rate was 2.45% (n = 67). Diabetes, tobacco use, and obesity did not independently increase the rate of infection. Revision surgeries had a trend toward higher infection rate; however, this did not meet statistical significance. There was no difference in the rate of infection between implants performed by physicians of different base specialties, cylinder leads vs. paddle leads, or between different prophylactic antibiotics. Implants performed at academic centers had a higher rate of infection when compared to implants performed in nonacademic settings. When patients received an occlusive dressing or post-operative antibiotics they had a lower rate of infection. CONCLUSIONS: The infection rate (2.45%) reported in this study is lower than the previously reported rates (3-6%) and are on par with other surgical specialties. This study did not show an increased rate of infection for patients that used tobacco, had diabetes or were obese. It's possible that given the low overall infection rate a larger study is needed to establish the true impact of these factors on infection. In addition, this study did not address the impact of poorly controlled diabetes mellitus (elevated hemoglobin A1c) vs. well-controlled diabetes. It can be concluded from this study that utilizing an occlusive dressing over the incision in the post-operative period decreases the rate of infection and should become the standard of care. This study also demonstrated the positive impact of post-operative antibiotics in decreasing the rate of infection. Studies in other surgical specialties have not shown this impact which would suggest that further research is needed.

Subsequent Pulse Generator Replacement Surgery Does Not Increase the Infection Rate in Patients With Deep Brain Stimulator Systems: A Review of 1537 Unique Implants at a Single Center.

INTRODUCTION: Deep brain stimulation (DBS) is a well-recognized treatment for patients with movement disorders and other neurological diseases. The implantable pulse generator (IPG) is a fundamental component of the DBS system. Although IPG implantation and replacement surgeries are comparatively minor procedures relative to the brain lead insertion, patients often require multiple IPG replacements during their lifetime with each operation carrying a small but possibly cumulative risk of complications. To better educate our patients and improve surgical outcomes, we reviewed our series of patients at our institution. METHODS: Using electronic health record data, we retrospectively reviewed all initial and subsequent IPG surgeries from patients who underwent at least one IPG surgery between the years of 2010 and 2015 at the Cleveland Clinic main campus. We calculated infection rates for initial IPG implantation surgeries and the infection rate for subsequent replacements. Fisher's exact tests were used to evaluate the chance of an infection between the initial implantation and replacement. Fisher's exact tests and simple logistic regression analyses were used to determine the predictive ability of selected demographic and clinical variables RESULTS: Our final sample included 697 patients and 1537 surgeries. For all patients, the infection rate at the first surgery was 2.01%; at the second surgery, it was 0.44%; and at the third surgery, it was 1.83%. When considering only patients that underwent at least three replacement surgeries (n = 114) the infection rate did not change in a significant manner with subsequent interventions compared to the first replacement. No other variable of interest was a significant predictor of infection. CONCLUSION: We did not find increasing rates of infection with subsequent IPG replacement procedures.

Chronic infection of a Brindley sacral nerve root stimulator.

The Finetech-Brindley sacral anterior root stimulator (SARS) is implanted for the treatment of bladder dysfunction following spinal cord injury (SCI) and has been successful in improving micturition in many patients with SCI. This case describes a 62-year-old man who presented with a chronic Staphylococcus aureus infection of a Brindley SARS 26 years after implantation following a T5 American Spinal Injury Association A spinal cord injury (T5 ASIA A SCI). He presented with chronic sacral osteomyelitis with a history of periodic implant erosion through the skin. Following a series of interventions, definitive management involved removal of the intradural electrodes and epidural and intradural phlegmon, ligation of the thecal sac and flap reconstruction. In the case of delayed infection of a Brindley SARS, removal of the entire system should be considered, especially if extension of the infection to the intradural compartment is suspected.

Frame-based stereotactic neurosurgery in children under the age of seven: Freiburg University's experience from 99 consecutive cases.

INTRODUCTION: Stereotactic frame-based procedures proved to be precise, safe and are of widespread use among adult patients. Regarding pediatric patients few data is available, therefore the use of the stereotactic frame remains controversial in this population. This motivated us to report our experience in stereotactic procedures in the youngest patients and review the literature concerning this subject. METHODS: All frame-based procedures performed in patients younger than seven years in the University of Freiburg during the last 10 years were retrospectively analyzed and discussed under the light of the current literature. RESULTS: The studied population was composed of 72 patients under the age of seven (mean 3.4±2.1 years-old), in whom 99 stereotactic procedures were performed. Brain tumor was present in 60 patients, hydrocephalus in five, cystic lesions in three, intracranial abscess in three and epilepsy in one patient. Stereotactic surgery was performed in 36 cases for brachytherapy, in 29 for biopsy, in 20 cases for cyst puncture, in eight for stereotactically guided endoscopic ventriculostomy, in five for catheter placement and in one case for depth electrode insertion. The overall complication rate was 5%. There were three cases of pin penetration through the skull, one case of frame dislocation after extensive cyst drainage and two skull fractures. Neurologic deficit related to frame fixation was observed in none of the cases. In disagreement with other authors, no case of pin related infection, air embolism, hematoma or CSF leak was observed. CONCLUSION: Frame-based stereotactic neurosurgery is a safe technique also in the youngest patients. Rather than the simple use of torque-limiting devices training and experience in the manual adjustment of the stereotactic frame in children have been proven to be crucial factors that contribute to reducing pin related complications.

Pacemaker endocarditis caused by Propionibacterium acnes in an adult patient with Ebstein's anomaly: a report of a rare case.

We report a rare case of a Brazilian adult woman with Ebstein's Anomaly who presented with pacemaker endocarditis caused by Propionibacterium acnes. Ebstein's Anomaly is a rare congenital malformation of the heart. Infective endocarditis is defined as an infection of heart valves, of the mural endocardium, of a septal defect, or of a cardiac electronic implantable device. Propionibacterium acnes is a skin commensal bacterium, that is usually considered as a contaminant, but can, on rare occasions, cause serious infections including endocarditis of prosthetic valves, native valves and cardiac electronic implantable devices. Diagnosis was made after nearly two years of investigation by identification of the organism by the MALDI-TOF technique and transoesophageal echocardiogram. The patient was successfully treated with daptomycin and device removal. She remains free of endocarditis after 32 months of follow-up.

Influence of vegetation size on the clinical presentation and outcome of lead-associated endocarditis: results from the MEDIC registry.

OBJECTIVES: The purpose of this study was to determine whether the clinical presentation of lead-associated endocarditis (LAE) is related to the size of lead vegetations and how size is related to bacteriology and clinical outcomes. BACKGROUND: Cardiac implantable electronic device (CIED) infection may present as either local pocket infection or bloodstream infection with or without LAE. LAE is associated with significant morbidity and mortality. METHODS: The clinical presentation and course of LAE were evaluated by the MEDIC (Multicenter Electrophysiologic Device Cohort) registry, an international registry enrolling patients with CIED infection. Consecutive LAE patients enrolled in the MEDIC registry between January 1, 2009 and December 31, 2012 were analyzed. The clinical features and outcomes of 2 groups of patients were compared based on the size of the lead vegetation detected by echocardiography (> or <1 cm in diameter). RESULTS: There were 129 patients with LAE enrolled into the MEDIC registry. Of these, 61 patients had a vegetation <1 cm in diameter (Group I) whereas 68 patients had a vegetation ≥1 cm in diameter (Group II). Patients in Group I more often presented with signs of local pocket infection, whereas Group II patients presented with clinical evidence of systemic infection. Staphylococcus aureus was the organism most often responsible for LAE, whereas infection with coagulase-negative staphylococci was associated with larger vegetations. Outcomes were improved among those who underwent complete device removal. However, major complications were associated with an open surgical approach for device removal. CONCLUSIONS: The clinical presentation of LAE is influenced by the size of the lead vegetation. Prompt recognition and management of LAE depends on obtaining blood cultures and echocardiography, including transesophageal echocardiography, in CIED patients who present with either signs of local pocket or systemic infection.

Reuse of internal pulse generator in cases of infection after deep brain stimulation surgery.

BACKGROUND: Hardware-related infection after deep brain stimulation (DBS) is one of the most serious complications and may need additional interventions. OBJECTIVES: To reuse the internal pulse generator (IPG) after DBS infection and to reduce the economic costs. METHODS: A database of 102 patients who underwent DBS surgery was used in the study. The incidence, clinical characteristics and management of infections while reusing the IPG after DBS-related infection were analyzed and reported. RESULTS: The overall infection rate was 5.9% (6 of 102 patients). Management consisted of total hardware removal followed by intravenous antibiotics. The IPG was at first kept in a solution, then rinsed with water and dried following sterilization with ethylene oxide gas at 38 °C for 18 h. When the treatment of the infection was finished, we reused the IPG and reimplanted the DBS. No hardware-related infection or other complications were observed after reimplantation. CONCLUSIONS: Management of hardware-related infections can be challenging. The medical and economic costs associated with these infections are enormous. The IPG can often be saved in infected patients. Thus, a significant cost burden is eliminated. Properly executed, reuse of IPG should markedly reduce the costs of these devices.

Surgical lead extraction for total occlusion of the superior vena cava by chronic lead infection after mustard procedure.

We present a case of total occlusion of the superior vena cava (SVC) with extensive thrombosis of the adjacent large veins secondary to multiple abandoned pacemaker leads with a superimposed chronic lead infection by Corynebacterium jeikeium. A surgical lead extraction was performed with an extensive en-bloc resection of the SVC together with the right subclavian vein and the right innomate vein. No venous reconstruction was required because of an unobstructed runoff via a well-developed azygos system.

Comparative outcomes of transvenous extraction of sprint fidelis and riata defibrillator leads: a single center experience.

INTRODUCTION: The FDA has issued class I advisories for Medtronic Sprint Fidelis(®) and St. Jude Medical Riata(TM) ICD lead families. Transvenous Riata(TM) ICD lead extraction is typically considered higher risk than Fidelis(®) extraction, based on longer duration from implant, presence of externalized conductors and lack of silicone backfill in the SVC and RV coils. However, published data comparing procedural outcomes between these leads are limited. METHODS: Records were reviewed for all patients undergoing transvenous extraction of Sprint Fidelis(®) or Riata(TM) ICD leads at the Vanderbilt Heart and Vascular Institute from July 2006 to April 2013 to ascertain indication for extraction, procedural details, complications, and 30-day mortality. RESULTS: There were significant differences between those undergoing extraction of a Sprint Fidelis(®) (n = 145) or Riata(TM) lead (n = 47). In the Riata(TM) group, device-related endocarditis was a more common indication for extraction, the mean duration of implant was longer, and larger excimer laser sheaths were required. Lead malfunction was a more common indication in the Fidelis(®) group. There were no statistically significant differences in median procedure duration, procedural success (97.9% vs 95.7%, P = 0.41), median length of hospital stay (1 day vs 1 day, P = 0.23), procedural complication rate (5.5% vs 10.6%, P = 0.23) or 30-day mortality (2.1% vs 2.1%, P = 0.98). Analyses excluding patients with device infection revealed similar results. CONCLUSION: Despite differences in baseline characteristics, this study indicates that Medtronic Sprint Fidelis(®) and St. Jude Riata(TM) ICD leads have similar procedural outcomes with transvenous lead extraction.