Generator Pocket Research Articles

Abstract 19654: Absence of Cardiovascular Implantable Electronic Device Infection in Remote Implantations Demonstrated by Fluorine-18 Positron Emission Tomography

Background: Cardiovascular implantable electronic device (CIED) infection can be very challenging and unnecessary device extraction can expose the patient to significant morbidity and mortality. Recent publications suggests that fluorine-18 ( 18 F-FDG) positron emission tomography (PET) has a high sensitivity and specificity to differentiate pocket and/or lead infections from non-infected devices older than 6 months. However, control groups were small (n≤10 patients) and the prevalence of increased 18 F-FDG uptake in not-infected CIED patients is unknown. Method: All patients with remote (>6month) ICD implantation and no clinical/laboratory evidence of infection undergoing 18FDG-PET in preparation for VT ablation from 2006 to 2011 were identified in a single tertiary center. Semi-quantiative ssessment of 18 F-FDG uptake was assessed in 4 sites (generator pocked, innominate vein, superior vena cava (SVC), and intracardiac space (right atrium/ventricle). using a semi-quantitative score assessing .Uptake was categorized in none (score = 0), mild (≤thoracic background activity[t1] ; score = 1), moderate (>thoracic background activity; score = 2), and severe hypermetabolism (very intense uptake; score = 3). Results: 65 contiguous patients were enrolled in this study. 18FDG PET signal uptake scores were 0 in 0%, 0%, 0%, 0% for generator pocket, innominate vein, SVC and intracardiac position, respectively. Resulting semiquantitative scores were 0.0±0.0 in (locations) and 0.1±0. Conclusion This as far as we know largest series on 18FDG PET scans in patients with remote device implantation demonstrates no incidence of increased tracer uptake in non-infected patients localized in ¼ This supports a potential use of 18 F-FDG PET/CT in differentiating patients with CIED infection from chronic implant changes, providing a new potentially new path in management of CIED infection.

EComment. Surgical complications of permanent cardiac pacemaker insertion

We read with interest the manuscript by Wu and Chen and we would like to comment on the surgical complications of intracardiac pacemaker implantation [1]. The use of permanent pacemakers (PPM) and implantable cardioverter-defibrillators (ICD) is increasing due to the expansion of indications and aging of the population. As a consequence, cardiologists and cardiothoracic surgeons have to deal with a broad spectrum of complications, which are sometimes under-estimated and life-threatening. The surgical complications of PPM and ICD may occur during the immediate or early post-operative period and can be related to venous access process (pneumothorax, hemothorax, air embolism, haematoma, arterial puncture, wound healing problems, infection, pain), to the pacemaker lead (cardiac perforation, tamponade, malposition or dislodgement of the lead), or to the generator device. In addition, other complicationed that may occur during the late post-operative period are related to infections, thrombosis, endocarditis, pulmonary embolism, superior vena cava (SVC) syndrome (due to thrombus formation and/or fibrosis of the pacing wires within the SVC) and pericarditis [2-5]. Ostovan and Aslani have reported on the successful treatment of massive pulmonary air embolism during a PPM implantation with air suctioning by the guide catheter inserted into main pulmonary artery via the left femoral vein. Treatment for air embolisms includes oxygen treatment, haemodynamic support and prevention of further air entry in the systemic circulation. The left lateral decubitus position can prevent the air obstruction of the pulmonary outflow tract (air can be moved toward the right ventricular apex) [2]. Aggarwal et al. found no difference in the incidence of intraoperative and early postoperative complications (up to two months after implantation) between single and dual chamber pacing systems [3]. Sohail et al., in their retrospective review of 189 patients with pacemaker related infections, found out that the most common clinical presentations were generator pocket infection (69%) and device-related endocarditis (23%). The leading pathogens were Coagulase-negative Staphylococci and Staphylococcus aureus, in 42% and 29% of cases, respectively. There was a broad spectrum of related complications such us septic arthritis, sternal or vetebral or femoral osteomyelitis, and abscesses in lung, spleen, liver, brain and perinephric area. Twenty-two (11.6%) patients had thrombosis of the subclavian vein or superior vena cava and 6 of them developed clinical manifestations of pulmonary embolism. Ninety-eight percent of patients underwent complete device removal combined with antibiotic treatment and 96% of patients were treated successfully [4]. Nineteen patients had lead extraction via a median sternotomy and the rest underwent percutaneous lead extraction. Interventional complications were more common in patients with a history of multiple device-related procedures and were related to tricuspid valve failure, laceration of subclavian vein, hemothorax, haematoma, fracture of lead tip, ventriculotomy and bleeding [4]. Right atrial thrombosis and pulmonary embolism are infrequent complications (0.6%-3.5%) and its therapeutic modalities include anticoagulation, thrombolysis and or surgery [5]. In conclusion, the knowledge of all potential complications of the PPM/ICD and its multidisciplinary approach is very important for its prevention and definitive treatment. Conflict of interest: none declared

Surgical Placement of Permanent Epicardial Pacing Systems in Very Low-Birth Weight Premature Neonates

Few studies have characterized the surgical outcomes following epicardial pacemaker placement in very low-birth weight infants with congenital complete heart block. This study was undertaken to review the surgical experience with this patient population based on data from a large multi-institutional registry. The Pediatric Cardiac Care Consortium (PCCC) multi-institutional database was retrospectively reviewed to identify premature, low-birth weight neonates that underwent surgical placement of an epicardial pacing system for heart block. We reviewed 179 patients with birth weights less than 1.5 kg that underwent a major operative procedure. Of these, 10 patients underwent surgical placement of an epicardial pacing system for heart block. Patients had heart block in otherwise structurally normal hearts (n = 6) or heart block associated with complex structural congenital cardiac anomalies (n = 4). There were no deaths directly related to the surgical placement of the epicardial pacing system. There were no immediate complications with either lead or generator placement. One generator pocket was revised three months following placement. Survival to discharge was 60%. The four deaths occurred at a mean of 11 days (range 1-45 days) following the procedure. Neonates born with prematurity and congenital heart block represent a challenging subset of patients with significant mortality. Generator pocket breakdown and infection have been considered barriers to optimal short- and long-term outcomes. Among cases in the PCCC, there were no deaths or major complications that could be attributed to permanent epicardial pacemaker placement. These data suggest that an aggressive surgical strategy may be justified.

Effect of a Novel Fixation Method for Spinal Cord Stimulators

Spinal cord stimulation is a well-established treatment for recalcitrant pain syndromes such as failed back surgery syndrome. Techniques minimizing surgical time and incision size and increasing lead stability are of great value to both the patient and implanting physician. We present a consecutive case series review of ten permanent percutaneous spinal cord implants utilizing a novel lead fixation device. The purpose of this case series review is to present initial findings of the minimized incision size and thoughts surrounding the new device and technique. Ten cases were performed utilizing the new device (fiXate) and technique. Incision size was dictated by adequate visualization of the fascial stratum as well as technical working space required for lead fixation and redirection to the generator pocket. Each spinal cord stimulator lead was affixed to the thoracodorsal fascia utilizing the novel device. In this consecutive series, the average midline incision size was 2.2 cm (range = 1.9-2.6 cm) which is greatly minimized through the use of the device. Not only may fiXate directly affect incision size, operating room and anesthesia time may also be lessened due to the semiautomated nature of the device. Of the cases performed, there were no complications or adverse events. Of note, there have been no reports of lead migrations during this case series, the average follow-up time being 18 weeks (range 11-26 weeks). These data suggest a new method of fixation can be utilized for percutaneous spinal cord stimulation that allows a reduction in incision size. Intuitively, reduction in incision size is relevant with regard to tissue morbidity and may also have implications with regard to infection. Use of the device may also reduce operating room and anesthesia time as well as provide greater stability than standard suture.

Axillary sub-pectoral pulse generator pocket for lowering defibrillation threshold

Axillary sub-pectoral pulse generator pocket for lowering defibrillation threshold

Rapidly Growing Mycobacteria (RGM) and Pacemaker Infection

Case Presentation  A 68-year-old male with dilated cardiomyopathy s/p defibrillator placement 3 years prior was admitted with a five-month history of fever, chills, and myalgias.  Outside records: • Blood culture positive for M. fortuitum, 5 months prior  On admission: • BP: 93/53 mmHg • No focal signs of infection of generator pocket • WBC: 4900 /μl • Hb: 10.1 g/dl • Platelets: 83000/μl • Blood culture grew M. fortuitum  Device infection was suspected.  Defibrillator was removed and a temporary pacemaker placed.  Defibrillator leads grew M. fortuitum.  Therapy started with amikacin 10mg/kg IV daily, cefoxitin 2 grams IV q 8 hours, and Levaquin 750 mg IV daily.  Blood culture was negative after one week of therapy. Mycobacterium Fortuitum Blood Agar Discussion  RGM are ubiquitous in the environment and have an indolent disease course.  It shows clinical signs after trauma or surgery.  Disseminated disease is seen in immuno-compromised patients.  Review of the English literature revealed 5 cases of RGM pacemaker infection.  Infections are mainly nosocomial (within 6 months), but delayed onset was also reported (>1 year).  Suspect infection in patients with implanted cardiovascular devices even with absence of localized signs of infection on the generator site.  Optimal treatment is removal of all device hardware, with empirical antibiotics until susceptibility results.  RGM are in general susceptible to amikacin, fluoroquinolones, cefoxitin and linezolid  The duration of therapy is 6 to 12 months.

Risk factors associated with early- versus late-onset implantable cardioverter-defibrillator infections

The infection rates of implantable cardioverter-defibrillators systems (ICDs) are higher than that of permanent pacemaker. Risk factors associated with ICD infection have not been characterized and are the subject of the current investigation. All patients who had an ICD implanted at Mayo Clinic Rochester between 1991 and 2008 were retrospectively reviewed. Each case of ICD infection was matched with two non-infected controls. Cases of ICD infection were further stratified by early- (≤ 6 months) versus late-onset (>6 months) infection. Multivariable analysis was performed to identify significant risk factors for ICD infection. Sixty-eight patients with ICD infection and 136 matched controls met the inclusion criteria. Thirty-five cases presented with early-onset infection and 33 had late-onset device infection. Staphylococcal species were the most common pathogens in both groups of patients. Patients with early-onset infection were more likely to present with generator pocket infection (p = 0.02). Patients with multiple comorbid conditions (high Charlson index) tended to have longer hospital stay during implantation admission (p = 0.009). In a multivariable logistic regression model, the presence of epicardial leads (odds ratio (OR) = 9.7, p = 0.03) and postoperative complications at the generator pocket (OR = 27.2, p < 0.001) were significant risk factors for early-onset ICD infection, whereas longer duration of hospitalization at the time of implantation (2 days versus 1 day: OR = 33.1, p < 0.001; ≥ 3 days versus 1 day: OR = 49.0, p < 0.001) and chronic obstructive pulmonary disease (OR = 9.8, p = 0.02) were associated with late-onset infections. Our study findings suggest that risk factors associated with early- and late-onset ICD infection are different. While circumstances that may increase the chances of pocket contamination in the perioperative period are more likely to be associated with early-onset ICD infection, overall poor health of the host may increase the likelihood of late-onset ICD infection. These factors should be considered when developing strategies to minimize risk of device infection.

A hybrid ICD extraction approach using laser and transfemoral extraction technique

Indications for pacemaker and implantable cardioverter defibrillator (ICD) implantations are rapidly expanding. Hence, device-related complications have increased the need for lead extraction. Lead extractions are performed percutaneously or by open surgery. We present a patient with isolated left ventricular noncompaction cardiomyopathy suffering from ICD pulse generator pocket and lead infection with aggregatibacter actinomycetem comitans bacteremia. The complete device was successfully removed by a hybrid two-step approach using excimer laser and transfemoral lead extraction technique in combination with mechanical traction via the subclavian vein. Thereby, open surgery with possible need for cardiopulmonary bypass could be avoided in this patient. A 55-year-old male was referred to the hospital due to exertional dyspnea, fatigue and pain in the ICD pulse generator pocket. ICD implantation was performed due to sustained ventricular tachycardia in isolated left ventricular noncompaction cardiomyopathy 10 years ago. ICD pulse generator was replaced due to battery depletion 3 years ago. On admission, the patient was hemodynamically stable, and the ICD pulse generator pocket was reddened and swollen. Laboratory chemistry revealed slightly elevated C-reactive protein levels (22 mg/l). No intracardiac vegetations were visualized by transesophageal echocardiography, left ventricular noncompaction was documented with a left ventricular ejection fraction of 51%. Coronary computed tomography revealed normal coronary arteries. The ICD pulse generator pocket was punctured and purulent material could be aspirated. Hence, diagnosis of …

Clinical Predictors of Cardiovascular Implantable Electronic Device‐Related Infective Endocarditis

Cardiovascular implantable electronic device (CIED)-related infective endocarditis (CIED-IE) is a serious complication of cardiac device infection and is associated with increased mortality. At present, there exist no criteria to predict CIED-IE in patients who present with CIED infection. We retrospectively reviewed all cases of CIED infection seen at Mayo Clinic Rochester between 1991 and 2008. CIED-IE was classified using pathologic and clinical criteria. Clinical predictors of CIED-IE were identified using logistic regression, and quantified using a summary score and plotted against the distribution of CIED-IE. Ninety-three (22.4%) of the 416 patients with CIED infection had CIED-IE. Host factors including chronic immunomodulator therapy exclusive of corticosteroid (odds ratio [OR], 3.79 [confidence interval (CI) 1.10, 13.04]), chronic corticosteroid therapy (OR, 2.15 [CI 0.93, 5.00]), hemodialysis (OR, 3.24 [CI 1.39, 7.55]), or remote infection (OR, 1.77 [CI 0.99, 3.14]) were associated with increased odds of CIED-IE. Patients with CIED-IE were at increased odds of presenting with fever (OR, 3.78 [CI 1.93, 7.40]), or malaise (OR, 1.87 [CI 1.02, 3.41]), and have findings of leukocytosis (OR, 3.61 [CI 1.51, 8.62]). In marked contrast, they were at decreased odds of exhibiting signs/symptoms of infection at the generator pocket site (OR, 0.19 [CI 0.10, 0.36]). Summary scores of 6 and 11 predicted CIED-IE in approximately 50% and 90% of cases, respectively. Certain comorbid conditions and systemic manifestations of infection were associated with CIED-IE. In contrast, pocket site infection was negatively associated with CIED-IE. These findings should assist clinicians in identifying patients who would more likely benefit from further investigation of CIED-IE with transesophageal echocardiography.

Implantation Success and Infection in Cardiovascular Implantable Electronic Device Procedures Utilizing an Antibacterial Envelope

Cardiovascular implantable electronic device (CIED) infection rates are increasing faster than implantation rates. More effective antimicrobial prophylaxis may help reduce CIED infections and improve clinical outcomes. The AIGIS(Rx)(®) antibacterial envelope is a polymer mesh implanted in the generator pocket with the CIED. After implantation it releases two antibiotics, minocycline and rifampin, that have been shown to reduce infections associated with other medical devices. The purpose of this retrospective cohort study is to determine the rate of CIED implantation success and CIED infection in procedures utilizing the antibacterial envelope. This study enrolled consecutive CIED procedures utilizing the antibacterial envelope at 10 US academic, community, and Veterans Affairs medical centers. Procedures following an explantation for a prior CIED infection or off-label use of the antibacterial envelope were excluded. The 624 eligible procedures (age 70 ± 13 years, 68.1% men, 27.2% renal insufficiency, 35.4% oral anticoagulant use, 67.8% replacement/revision procedures) utilized pacemakers (35%), implantable cardioverter-defibrillators (ICD)(29%), and cardiac resynchronization therapy with defibrillator devices (CRT-D)(36%). Nearly half of the patients (49%) had at least three predefined risk factors for CIED infection. CIED implantation was successful in 621 procedures (99.5%[95% confidence interval (CI) 98.8-99.9]). There were three major infections (0.48%[95%CI 0.17-1.40]) after 1.9 ± 2.4 months follow-up. The infections followed one ICD revision and two CRT-D replacements. There were seven deaths; none was a result of the antibacterial envelope or the CIED procedure. CIED procedures that utilized an antibacterial envelope had a high rate of CIED implantation success (>99%). Although the follow-up to date is short, there was also a low rate of infection (<0.50%) in this population at high risk for CIED infection.

Removal of an Infected Permanent Pacemaker through a Right Atriotomy without Cardiopulmonary Bypass Via a Right Thoracotomy

Kwang Ho Choi, M.D.*, Young-Chul Yoon, M.D.*, Kyung-Taek Park, M.D.*, Yang-Haeng Lee, M.D.*, Youn-Ho Hwang, M.D.*, Kwang-Hyun Cho, M.D.*. Korean J Thorac Cardiovasc Surg 2010;43:421-3. https://doi.org/10.5090/kjtcs.2010.43.4.421

Treatment of an Infected Pacemaker Pocket With an Antimicrobial Envelope

This article reports the successful treatment of an infected permanent pacemaker pocket after pulse generator replacement in an immunosuppressed patient by means of localized surgical revision of the pulse generator pocket and placement of a sustained-release combination antibacterial envelope in the revised pocket.

Prevalence of bacterial colonization of generator pockets in implantable cardioverter defibrillator patients without signs of infection undergoing generator replacement or lead revision

This study was designed to evaluate the prevalence of bacterial colonization of generator pockets in implantable cardioverter defibrillator (ICD) patients without signs of infection and to analyse the impact of bacterial colonization on the incidence of device infection during follow-up. In 122 ICD patients undergoing generator replacement or surgical lead revision between January 2006 and July 2008, microbiological cultures of generator pockets and extracted leads were consecutively obtained. Patients with clinical evidence of a device infection were excluded. Positive cultures from the generator pocket and leads were found in 40 (33%) patients. The most common bacteria isolated were coagulase negative staphylococci (68%). During a median follow-up time of 203 days after the revision device infection occurred in three [7.5%, confidence interval (CI) 1.6-20.4%] patients with a positive culture vs. two (2.4%, CI 0.3-8.5%) patients with a negative culture (P = 0.33). Time from revision to infection was 108 +/- 73 days in patients with positive culture vs. 60 +/- 39 days in patients with negative culture (P = 0.50). A third of ICD patients undergoing generator replacement or lead revision have an asymptomatic bacterial colonization of generator pockets. After revision 7.5% of these patients develop a device infection with the same species of microorganism.

Cardiovascular Implantable Electronic Device Infection in Patients withStaphylococcus aureusBacteremia

Staphylococcus aureus bacteremia (SAB) in patients with cardiovascular implantable electronic devices (CIED), including permanent pacemakers (PPMs) and implantable cardioverter-defibrillators (ICD), can be the sole manifestation of device infection. To assess clinical factors associated with CIED infection, we retrospectively reviewed all patients with both CIED and SAB seen at Mayo Clinic Rochester between 2001 through 2006. CIED infection was defined using microbiological and clinical criteria. Of the 62 patients with SAB and a CIED, 22 patients (35.5%) had CIED infection. The generator pocket was identified as the source of bacteremia in seven (11%) patients. The majority of CIED infections were device-related infective endocarditis (12 of 22, 55%). Thirty percent of patients presenting with SAB greater than 1 year after device implantation had CIED infection; all but one had CIED-related infective endocarditis. Sixty percent of ICD patients (12 of 20) with SAB had CIED infection, compared with 24% of PPM patients (10 of 42, P = 0.01). On univariate analysis factors associated with CIED-related infective endocarditis included device type [odds ratio (OR) for ICD 13.3, 95% confidence interval [CI] 2.1, 84.9) and presence of a prosthetic heart valve (OR 6.8 95% CI 1.1, 43.4). CIED infection is common in patients with SAB. The presence of an ICD and prosthetic heart valve were associated with CIED-related infective endocarditis. Subsequent work should focus on prospectively characterizing the subset of patients with CIED infection who present with SAB as the sole manifestation of their device infection. (PACE 2010; 407-413).

A case of total pacemaker extrusion

Pacemaker extrusion is an extremely rare but serious complication. It is a consequence of an infection and/or small pacemaker pocket. We report a case of a total pacemaker extrusion due to a small pulse generator pocket.

Efficacy of Antibiotic Prophylaxis Before the Implantation of Pacemakers and Cardioverter-Defibrillators

Although routinely administered, definitive evidence for the benefits of prophylactic antibiotics before the implantation of permanent pacemakers and implantable cardioverter-defibrillators from a large double-blinded placebo-controlled trial is lacking. The purpose of this study was to determine whether prophylactic antibiotic administration reduces the incidence of infection related to device implantation. This double blinded study included 1000 consecutive patients who presented for primary device (Pacemaker and implantable cardioverter-defibrillators) implantation or generator replacement randomized in a 1:1 fashion to prophylactic antibiotics or placebo. Intravenous administration of 1 g of cefazolin (group I) or placebo (group 2) was done immediately before the procedure. Follow-up was performed 10 days, 1, 3, and 6 months after discharge. The primary end point was any evidence of infection at the surgical incision (pulse generator pocket), or systemic infection related to be procedure. The safety committee interrupted the trial after 649 patients were enrolled due to a significant difference in favor of the antibiotic arm (group I: 2 of 314 infected patients-0.63%; group II: 11 of 335 to 3.28%; RR=0.19; P=0.016). The following risk factors were positively correlated with infection by univariate analysis: nonuse of preventive antibiotic (P=0.016); implant procedures (versus generator replacement: P=0.02); presence of postoperative hematoma (P=0.03) and procedure duration (P=0.009). Multivariable analysis identified nonuse of antibiotic (P=0.037) and postoperative hematoma (P=0.023) as independent predictors of infection. Antibiotic prophylaxis significantly reduces infectious complications in patients undergoing implantation of pacemakers or cardioverter-defibrillators.

Management of infections involving implanted cardiac electrophysiologic devices

Indications for cardiac electrophysiologic device implantation have expanded, and the target demographic has widened. Unfortunately, these changes have been accompanied by an increase in cardiac device-associated infections out of proportion to the increase in implantation rate. Diagnosing a cardiac device infection may be challenging because of the spectrum of clinical manifestations, ranging from isolated generator pocket pain to frank sepsis with clear evidence of endocarditis. Any component of the device may be involved, but the cornerstone of therapy remains extraction of the device and its leads along with appropriate antibiotic treatment. Given the inherent risks of lead extraction, making the correct diagnosis is paramount. This review outlines the epidemiology, pathophysiology, clinical manifestations, diagnosis, and management of cardiac device infections.

Pacemaker infection due to Vibrio alginolyticus

We report a case of pacemaker infection due to Vibrio alginolyticus, after exposure to sea water. V. alginolyticus has been seldom responsible for human infections, but may be an emerging pathogen, most of the time implicated in gastroenteritis and skin and soft tissue infections after exposure to sea water. In this case, the patient was infected because of a persistent wound dehiscence at the generator pocket, after implantation of a pacemaker. Modalities of treatment for achieving bacterial eradication are discussed.

Infections of electrophysiologic cardiac devices

Infections related to electrophysiologic cardiac device placement are increasing dramatically and are associated with adverse outcomes. With the US population aging and living longer, cardiac devices are utilized in an older population with significant comorbidities, making the threat from infectious complications significant. Electrophysiologic cardiac devices typically include an implanted pulse generator and an intravascular lead. Infection may occur at any component of the device, resulting in varied presentations. Bacteremia in cardiac device recipients may reflect primary generator pocket infection, or alternate sources of bacteremia may result in secondary hematogenous lead infection. This review focuses on the pathology, diagnosis, management and prevention of electrophysiologic cardiac device infections.

Pacemaker infection with propionibacterium and a nephritic sediment

Like any other implanted foreign body, the different parts of pacemakers (pulse generator pocket, epicardial or transvenous leads) can become infected. Staphylococcus aureus and coagulase-negative staphylococci are the causative organisms in most of the cases (65 â 75%), propionibacterium is described to be involved in only 1% of cases. This report describes a case of nephritic sediment in a young female patient with a pacemaker implantation 9 years ago because of a third degree atrioventricular block, in which a battery exchange was necessary 2.5 years ago. This young patient was referred from a nephrologist for renal biopsy because of a nephritic sediment and diffuse complaints including low-grade fever with a suspected underlying autoimmune disease. The laboratory examinations were all negative with the exception of a diminished C3 complement level. Blood cultures were positive for propionibacterium, but the microbiologists were considering it as a contamination. 11 more blood cultures collected thereafter were all positive and a transesophageal ultrasound revealed a small vegetation at 1 of the transvenous electrodes of the pacemaker. Because of a penicillin allergy she was treated with clindamycin, and the blood cultures were negative after a few days. After a full course (7 weeks) of antibiotic treatment the C3 complement level normalized and a series of 10 blood cultures remained negative 10 â 15 days after discontinuation of antibiotic therapy. Discussing all the differential diagnoses of a nephritic sediment combined with hypocomplementemia, positive blood cultures and a vegetation on a pacemaker electrode in the transesophageal ultrasound, the diagnosis of an immune complex glomerulonephritis due to a propionibacterium pacemaker infection needs no confirmation by renal biopsy.