Current best practices and guidelines. Assessment and management of complications in infective endocarditis

The unique clinical features and outcome of infectious endocarditis and vertebral osteomyelitis co-infection

OBJECTIVE

The clinical significance of vertebral osteomyelitis and infectious endocarditis co-infection is unclear. This study investigates the rate, clinical features, and outcome of vertebral osteomyelitis with and without concomitant infectious endocarditis.

METHODS

A retrospective study of all cases of osteomyelitis with spinal imaging (n = 176), from January 2007 to April 2013, that were diagnosed as vertebral osteomyelitis. Sixty-two patients with spontaneous vertebral osteomyelitis were identified after excluding postsurgical, decubitus ulcers and spinal metastases. Seventeen (27%) were identified with concomitant infectious endocarditis.

RESULTS

All patients presented with back pain and 59% were diagnosed with infectious endocarditis subsequent to vertebral osteomyelitis. Distinguishing features among the co-infection group include the increased use of transesophageal echocardiography (94% vs 58%, P = .004), predisposing cardiac conditions (59% vs 16%, P = .001), and Gram-positive bacteremia, of which Streptococcus sp. and Enterococcus sp. were more common (35% vs 11%, P = .026). Adverse neurologic events were increased significantly in the co-infection group (59% vs 22%, P = .006). On transesophageal echocardiography, 88% of co-infection patients had highly mobile vegetations, 9 of which measured 10 mm or more. The overall mortality was 41% and 29% in the co-infection and lone vertebral osteomyelitis groups, respectively (P = .356). One-year mortality was identical for both groups at 24% (P = .999), and higher than previously reported (11.3% for lone vertebral osteomyelitis).

CONCLUSIONS

Patients with vertebral osteomyelitis, in whom infectious endocarditis is not excluded, are at increased risk for adverse neurologic events and mortality. The prompt diagnosis of infectious endocarditis, and associated high-risk features that may benefit from surgical intervention, require early evaluation by transesophageal echocardiography.

Infective endocarditis in an Indian setup: Are we entering the 'modern' era?

Background:

The clinical profile of infective endocarditis (IE) has been continuously evolving over last 3-4 decades as highlighted by many studies from developed world.

Objectives:

To evaluate the recent changes in the spectrum and clinical profile, and outcome of IE in an Indian setup.

Materials and Methods:

This was a descriptive, cross-sectional study. Demographic, clinical, characteristics, treatment, and outcome were examined in ‘definite’ cases of IE admitted at our institute between July 2005 and December 2010.

Results:

61 ‘definite’ cases were identified. Mean patient age was 49.3 ± 13.7 years. Male to female ratio was 3.3:1. Rheumatic heart disease was the underlying heart disease in 23 (37.7%) patients. 33 (54.1%) patients had already received antibiotic therapy before presentation to us. Blood cultures were positive in 41 (67.2%) patients. Streptococci and staphylococci were the commonest microbial isolates, 9 (21.4%) patients each. Transesophageal echocardiography (TEE) was done for all the patients. Vegetations were detected in 54 (88%) patients. Surgery was done in 30 (49.2%) patients. In-hospital mortality happened in 4 (6.5%) patients.

Conclusions:

We recorded several new trends, like: 1) an increasing age, 2) an increasing proportion of patients with no previously known heart disease, 3) improving culture positivity rates, 4) rise in staphylococcal infections, 5) increased usage of TEE, 6) high elective surgical rate, and 7) apparent improved survival rates. These changes point to the fact that ‘modern era’ changes in the profile of IE have started to appear in a selected population in India.

Infective endocarditis presenting with loin pain

A 28-year-old previously healthy man presented to a peripheral hospital several hours after onset of acute right flank pain. A kidney stone was suspected clinically as the patient was otherwise well appearing, afebrile and normotensive. Renal function was normal and urinalysis showed no haematuria or white blood cells. A contrast CT scan of the abdomen revealed a filling defect in the ventral branch of the right renal artery with no distal perfusion suggesting a renal embolus. Subsequent investigations revealed blood cultures positive for coagulase negative staphylococcus and echocardiogram showed a bicuspid aortic valve, a dilated aortic root and moderately dilated ascending aorta. The patient was transferred to a tertiary care hospital and transesophageal echocardiogram revealed severe aortic insufficiency and thickening of the aortic valve suggestive of endocarditis. Following antibiotic treatment, blood cultures became negative and the patient underwent successful semi-urgent aortic root replacement. Renal function remained normal throughout.

Bacterial endocarditis presenting with unilateral renal artery occlusion treated with the Rinspirator Thrombus Removal System rinsing and thrombectomy device and suction thrombectomy

We report a 36-year-old man who presented with unilateral flank pain caused by renal artery occlusion with ischemia and infarction from septic emboli secondary to bacterial endocarditis. We treated the occlusion with a novel rinsing and aspiration device, the Rinspirator Thrombus Removal System (ev3, Plymouth, Minn) and suction thrombectomy, which resulted in significant revascularization of the kidney and relief of symptoms. Postprocedural imaging demonstrated marked improvement in renal vascularization, with only small areas of infarction. This technique may be useful in patients where the embolic material is chronic or thrombolytic agents are contraindicated.

Gallbladder infarction complicating infective endocarditis

Infective endocarditis with systemic embolization of the gallbladder vasculature is very rare. We describe a case of subacute infective endocarditis in an adult complicated by embolization of the right hepatic artery with subsequent gallbladder infarction. In these cases, appropriate antibiotic therapy should be given before and after cholecystectomy. Gallbladder resection should be performed before valve replacement to decrease the potential seeding of a prosthetic valve.

Severity of gentamicin's nephrotoxic effect on patients with infective endocarditis: a prospective observational cohort study of 373 patients

BACKGROUND

Gentamicin is often used to treat infective endocarditis (IE). Gentamicin is highly effective, but its applicability is reduced by its nephrotoxic effect. The aim of this study was to quantify the nephrotoxic effect of gentamicin and the association between the nephrotoxic effect and mortality in patients with IE.

METHODS

A prospective observational cohort study was performed at 2 tertiary university hospitals in Copenhagen from October 2002 through October 2007; 373 consecutive patients with IE were included. A total of 287 (77%) of the patients received gentamicin treatment (median duration, 14 days); dosage was adjusted according to daily serum creatinine and trough serum gentamicin levels. Kidney function was determined by estimated endogenous creatinine clearance (EECC). Statistical correlation between gentamicin and EECC change was analyzed, and the association between mortality and nephrotoxicity was investigated.

RESULTS

The primary bacteriological etiologies were as follows: Streptococcus species (37.1%), Staphylococcus aureus (18.2%), and Enterococcus species (16.1%). In the gentamicin group, the mean EECC change was an 8.6% decrease, but in the no-gentamicin group, the mean change was an increase of 2.3% (P = .05). The decrease in EECC was significantly correlated with the duration of gentamicin treatment: a 0.5% EECC decrease per day of gentamicin treatment (P = .002). The decrease in EECC during hospitalization was not related to postdischarge mortality. The mean duration of follow-up was 562 days.

CONCLUSIONS

The nephrotoxic effect of gentamicin is directly related to treatment duration, with a decrease in EECC of 0.5% per day of gentamicin treatment. In patients treated with gentamicin, the in-hospital decrease in EECC was not related to postdischarge mortality. Consequently, this study does not support abolishment of gentamicin in treatment of IE.

Radiologic manifestations of extra-cardiac complications of infective endocarditis

Infective endocarditis (IE) is a disease with high morbidity and a mortality rate of 9-30%, even with appropriate diagnosis and therapy. Septic emboli, caused by IE, can affect any organ or tissue in the body with an arterial supply and occur in 12-40% of IE cases. The most common extra-cardiac organ system involved in IE is the central nervous system. Other organs frequently involved are the lungs (especially in right-sided IE), spleen, kidneys, liver, and the musculoskeletal system. In addition, the arterial system itself is susceptible to the development of potentially fatal mycotic aneurysms. As extra-cardiac complications often antedate the clinical diagnosis of IE, it is important that the diagnosis is suggested when characteristic findings are encountered during imaging. In addition, imaging is often used to monitor the extent of complications in patients with a known diagnosis of IE.

Surgery for infective endocarditis

Infective endocarditis (IE) is estimated to have an incidence of five to seven cases per 100,000 person-years. Although not a common clinical entity, IE is associated with substantial morbidity and risk of mortality. IE, especially infections due to Staphylococcus aureus, are increasingly healthcare-associated infections. Despite significant advances in diagnosis and management, mortality from IE has changed little since the availability of penicillin; however, this lack of improvement in mortality is likely due to an increasing number of infections from more virulent and drug-resistant pathogens coupled with infections that occur in patients with other comorbidities and those associated with prosthetic valves. Surgery is an important part of therapy for many patients, but surprisingly, little evidence is available to help clinicians determine which patients will benefit most from surgical therapy for the management of IE.

Septic pulmonary embolism in Korea: Microbiology, clinicoradiologic features, and treatment outcome

OBJECTIVES

The aim of this study was to investigate the clinicoradiologic features, microbiologic data, primary sites of infection, and treatment results for patients with septic pulmonary embolism (SPE) in Korea.

METHODS

We retrospectively analyzed 21 SPE patients including "definite" and "probable" cases.

RESULTS

On CT scan, peripheral nodules were the most common lesions (89.0%), followed by non-nodular infiltrates (7.0%) and wedge-shaped peripheral lesions (3.2%). Cavitation and feeding vessel sign, more specific to SPE were identified in 10.4% and 6% of all the lesions, respectively. Transthoracic echocardiography revealed significant abnormalities in three of 13 patients with an additional finding of vegetation in only one of five patients when studied by transesophageal echocardiography. In 15 patients, primary sites of infection were found, and three causative organisms were isolated in 16: K. pneumoniae (8); S. aureus (6); and viridans streptococci (2). All patients received parenteral antimicrobial therapy with or without drainage of the extrapulmonary infection and 18 recovered.

CONCLUSIONS

Although the pathogens of SPE may differ depending on the primary foci of infection, early diagnosis and prompt antimicrobial therapy with radiologic or surgical intervention can lead to a successful treatment outcome.

Spontaneous pyogenic vertebral osteomyelitis and endocarditis: incidence, risk factors, and outcome

PURPOSE

The relationship between pyogenic vertebral osteomyelitis and infectious endocarditis is uncertain. This study investigates the incidence and risk factors of infectious endocarditis in patients with pyogenic vertebral osteomyelitis, and the outcome of pyogenic vertebral osteomyelitis with and without associated infectious endocarditis.

METHODS

A retrospective record review was conducted of all cases of vertebral osteomyelitis from January 1986 to June 2002, occurring in a tertiary referral hospital. Patients were followed for at least 6 months with careful attention to detection of infectious endocarditis and relapses.

RESULTS

Among 606 patients with infectious endocarditis, 28 (4.6%) had pyogenic vertebral osteomyelitis. Among 91 cases of pyogenic vertebral osteomyelitis, 28 (30.8%) had infectious endocarditis. In 6 patients with no clinical signs of infectious endocarditis, the disease was established by routine echocardiography. Infectious endocarditis was more common in patients with predisposing heart conditions and streptococcal pyogenic vertebral osteomyelitis infection. Overall, pyogenic vertebral osteomyelitis in-hospital mortality was 11% (7.1% with infectious endocarditis). Twelve of 25 patients with infectious endocarditis with uncomplicated pyogenic vertebral osteomyelitis were treated for 4 to 6 weeks (endocarditis protocol), with no pyogenic vertebral osteomyelitis relapses.

CONCLUSIONS

When specifically sought, the incidence of infectious endocarditis is high in patients with pyogenic vertebral osteomyelitis. Oral therapy may be an option for uncomplicated pyogenic vertebral osteomyelitis; nevertheless, in gram-positive infections, this approach should only be considered after excluding infectious endocarditis. Favorable outcome with shorter treatment in uncomplicated pyogenic vertebral osteomyelitis associated with infectious endocarditis suggests that prolonged therapy may not be needed in this subgroup except for those infected by difficult to treat microorganisms, such as methicillin-resistant Staphylococcus aureus or Candida spp.

Septic Pulmonary Embolism

BACKGROUND

Septic pulmonary embolism (SPE) is an uncommon disorder with an insidious onset and is difficult to diagnose.

STUDY OBJECTIVES

To characterize the presenting features and clinical course of patients with SPE.

DESIGN

Retrospective study.

SETTING

Tertiary care, referral medical center.

PATIENTS

Fourteen subjects with SPE diagnosed during a 6-year period between 1996 and 2002.

INTERVENTIONS

None.

RESULTS

The median age of these patients was 37.5 years (range, 14 to 81 years) and included five women. Presenting symptoms included fever (93%), dyspnea (36%), pleuritic chest pain (29%), cough (14%), and hemoptysis (7%). The median duration of symptoms before diagnosis was 18 days (range, 5 to 180 days). A potential source or underlying condition that predisposed to SPE was identified in all 14 patients and included Lemierre syndrome (4 patients), central venous catheter infection (3 patients), prosthetic cardiac valve (2 patients), and pacemaker infection (2 patients). Two patients had a focal extrapulmonary infection, and one patient was an IV drug user. Most common pathogens were staphylococcal species (eight patients) and fusobacterium (four patients). Chest radiographic presentation was usually nonspecific, but CT was more helpful and revealed multiple nodular opacities peripherally, often with cavitation. Transesophageal echocardiography was performed in eight patients and demonstrated infectious vegetations in four cases. Aside from antimicrobial therapy and removal of infected devices, the management of these patients included cardiac surgery (two patients), thoracoscopic surgery with decortication (one patient), and tube thoracostomy (one patient). All 14 patients recovered from their illness.

CONCLUSIONS

We conclude that SPE presents with variable and often nonspecific clinical and radiographic features. The diagnosis is usually suggested by the presence of a predisposing factor, febrile illness, and CT findings of multiple, nodular lung infiltrates peripherally, with or without cavitation.

Discitis

Discitis is not an uncommon condition and can be potentially life threatening if diagnosed late. This article reviews recent publications and discusses the clinical presentation, pathoaetiology, diagnosis, treatment and pitfalls.

Infective Endocarditis in Patients with Kidney Failure: Chronic Dialysis and Kidney Transplant

Physicians who treat patients with infective endocarditis (IE) are encountering a growing number of dialysis and kidney transplant patients. Both groups have 30 to 100 times higher risk of IE, with 1-year mortalities of 40% to 60%. The predominant organisms causing IE are gram positive, with 60% to 80% of cases due to Staphylococcus aureus, and another 10% to 20% of cases due to coagulase-negative staphylococci. Renal transplant patients may develop fungal IE, but this risk is primarily in the first 3 months after transplant. In addition to blood cultures, transesophageal echocardiogram is the most useful diagnostic examination for IE in these patients. Initial antibiotic therapy, pending final culture and antibiotic susceptibility results, should provide coverage against the most common organisms and allow for the potential of either methicillin or vancomycin-resistant species. Removal of infected hemodialysis access devices and at least 4 to 6 weeks of intravenous antibiotics are recommended. Antibiotic prophylaxis against IE has been recommended for all dialysis and renal transplant patients, but this strategy is controversial and unproven.