Many Faces of Infective Endocarditis- Radiological Features of Extracardiac Complications.

Transcription

1 Many Faces of Infective Endocarditis- Radiological Features of Extracardiac Complications. Poster No.: C-0923 Congress: ECR 2014 Type: Educational Exhibit Authors: M. Elsayed, M. Chiphang; Wigan/UK Keywords: Infection, Acute, Abscess, Complications, MR, Echocardiography, CT, Vascular, Cardiovascular system, Cardiac DOI: /ecr2014/C-0923 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 25

2 Learning objectives Extracardiac complications of IE can precede the clinical diagnosis of IE. It is therefore important that the diagnosis is suggested when a Radiologist is faced with typical and unusual imaging findings. Pictorial review demonstrating extracardiac complications of IE. Discuss clinical and radiological clues to aid prompt diagnosis. Background IE is a microbial infection of the endocardium and heart valves, most commonly by bacteria. Although the primary focus of the infection is confined to the endocardium, microbial shedding by continuous bacteremia and embolization of vegetation fragments makes IE a true systemic infection. Incidence ranges from 2-5 cases per 100,000 per annum. Historically, chronic rheumatic heart disease was the primary risk factor, but in the recent years new risk groups have emerged. IE is a serious systemic infection with multiple cardiac and extracardiac manifestations. It is associated with a high morbidity and mortality rate of 9-30% (it can be higher in elderly patients, patients with prosthetic valve endocarditis and antibiotic resistant endocarditis). It is fatal if it is not diagnosed or treated early and promptly. It remains to be a diagnostic challenge especially in elderly people as symptoms and signs can be non-specific. Nowadays, molecular imaging, PET-CT and single photon emission computed tomography (SPECT/CT) have an increasing role in diagnosis IE. It can be classified into four categories. Native valve endocarditis Intravenous drug abuse endocarditis (IVDA) Prosthetic valve endocarditis Pacemaker endocarditis and nosocomial endocarditis Page 2 of 25

3 Intravenous drug abusers are at most risk, commonly affecting the tricuspid valve causing multiple septic pulmonary emboli. Cardiogenic predisposing factors includes rheumatic valve disease (24%), mitral valve prolapse/ regurgitation, congenital heart diseases (19%), bicuspid aortic valve and prosthetic valve. Non-cardiogenic predisposing factors includes, poor dental hygiene, long term heamodialysis, diabetes mellitus and HIV. Pathophysiology: IE typically occurs at sites of pre-existing endocardial damage The most common pathogens are Staph aureus and B-heamolytic Streptococcus. They are a virulent aggressive organisms and are responsible for more than 80% of all acute IE cases. They can also affect a normal heart. These bacteria have great ability to adhere to and colonize damaged valves as these areas attract platelets and fibrin. This will eventually lead to development of vegetations, which are composed of organisms, fibrin and platelets. Then they break off to shoot systemic emboli, leading to infarction/ abscess formation. Cases have also been reported in association with urinary tract infection and large bowel neoplasm. Clinical manifestations: General manifestations are rather non-specific mainly consisting of constitutional symptoms such as persistent fever, chills and rigors, anorexia, night sweats,pleuritic chest pain, cough, and fatigability. Findings and procedure details A Pictorial review of extracardiac radiological manifestations. Examples Include: CNS: Brain infarction. Larynx: Ortner's Syndrome Page 3 of 25

4 Lung: Septic pulmonary emboli, pneumonia Spleen: Splenic infarcts, splenic abscess Liver: Liver abscess Kidney: Renal Infarcts. Musculoskeletal: Discitis Vascular: Mycotic aneurysms, infected femoral vein thrombus. CNS: Brain infarcts Fig. 1: Axial FLAIR (A), DWI(B) and corresponding ADC map (C). (A) Showing abnormal white matter high signal change. (B) showing multifocal areas of restricted diffusion (arrows). (C) corresponding changes on ADC mapping. Features are all in keeping with multifocal acute infarcts on a background of chronic ischemic change. Larynx:Ortner'sSyndrome. Page 4 of 25

5 Fig. 2: Axial and coronal reformatted contrast enhanced CT, in a patient presenting with left vocal cord palsy three month after diagnosis of IE. CT images show asymmetric vocal cords (Arrows) with no glottic,supra or infra glottic neoplastic lesions. initially, no clear cause was identified for the vocal cord palsy and therefore further investigations were carried out. Page 5 of 25

6 Fig. 3: Sagtital STIR MRI (A) of the same patient as figure (2) at the time of discitis showing a normal inferior wall of the arch of aorta. (B) Sagittal reformatted CT of the same patient presenting with hoarseness and left vocal cord palsy three month later, now showing a pseudo aneurysm from the inferior arch of the aorta. This represents cardiovascular hoarseness/ortner"s syndrome- a somewhat rare cause of hoarseness. Page 6 of 25

7 Fig. 4: Axial (A) and Volume Rendered Reformatted images (B), showing a mycotic aneurysm from inferior wall of aortic arch (Arrows). Lung: Septic pulmonary emboli, pneumonia. Fig. 5: Same patient as Figure 14 CT reformatted images in lung windows showing multiple ill defined cavitating pulmonary septic emboli. Cardiovascular: Vegitation/ Mural Thrombus. Page 7 of 25

8 Fig. 6: Axial contrast enhanced CT Pulmonary angiogram showing an aberrant filling defect in the left ventricles (arrow) suggestive of a vegetation/ thrombus confirmed on an Echocardiogram in a patient with IE. Spleen: Splenic infarct, abscess. Page 8 of 25

9 Fig. 7: Axial contrast enhanced CT scan of the abdomen in Portal venous phase showing multifocal infarcts in spleen in two different patients. A suspicion of IE was raised which was later confirmed by Echocardiogram. Fig. 8: Coronal reformat of two different patients as figure (6), demonstrating the splenic infarcts (arrow). Page 9 of 25

10 Fig. 9: Sagittal (A) and Axial (B) contrast enhanced CT scan showing splenic abscess. Renal: Renal infarcts. Page 10 of 25

11 Fig. 10: CT coronal reformatted portal venous phase scan of two different patients. Patient (A) showing splenic and renal infarcts (Arrows). Patient (B) with multifocal wedge shaped renal infarcts (Arrows). Liver: Liver abscess. Page 11 of 25

12 Fig. 11: Axial Contrast enhanced CT of abdomen showing hepatic abscess with extra hepatic extension into the retroperitoneum. Patient subsequently was diagnosed to have IE on Echocardiogram Page 12 of 25

13 Musculoskeletal: Discitis Fig. 12: Sagittal T2 (A) and Sagittal STIR (B)MRI images illustrating mid thoracic discitis seen as abnormal high signal change in the disc and STIR sequences showing Page 13 of 25

14 the high marrow signal in adjacent vertebral bodies. Note the small epidural abscess (Black arrow). Fig. 13: Same patient as figure (12),Axial T1 fat suppressed post gadolinium sequences, showing a small right paravertebral abscess collection secondary to discitis (arrows). Vascular: Mycotic aneurysms, infected femoral vein thrombus. Page 14 of 25

15 Fig. 14: (A) Axial and sagittal Post contrast CT images showing left femoral vein DVT with superimposed infection seen as gas locules in the left femoral vein in a patient with known IV drug abuse. Images for this section: Page 15 of 25

16 Fig. 1: Axial FLAIR (A), DWI(B) and corresponding ADC map (C). (A) Showing abnormal white matter high signal change. (B) showing multifocal areas of restricted diffusion (arrows). (C) corresponding changes on ADC mapping. Features are all in keeping with multifocal acute infarcts on a background of chronic ischemic change. Fig. 3: Sagtital STIR MRI (A) of the same patient as figure (2) at the time of discitis showing a normal inferior wall of the arch of aorta. (B) Sagittal reformatted CT of the same patient presenting with hoarseness and left vocal cord palsy three month later, now showing a pseudo aneurysm from the inferior arch of the aorta. This represents cardiovascular hoarseness/ortner"s syndrome- a somewhat rare cause of hoarseness. Page 16 of 25

17 Fig. 2: Axial and coronal reformatted contrast enhanced CT, in a patient presenting with left vocal cord palsy three month after diagnosis of IE. CT images show asymmetric vocal cords (Arrows) with no glottic,supra or infra glottic neoplastic lesions. initially, no clear cause was identified for the vocal cord palsy and therefore further investigations were carried out. Fig. 4: Axial (A) and Volume Rendered Reformatted images (B), showing a mycotic aneurysm from inferior wall of aortic arch (Arrows). Page 17 of 25

18 Fig. 5: Same patient as Figure 14 CT reformatted images in lung windows showing multiple ill defined cavitating pulmonary septic emboli. Page 18 of 25

19 Page 19 of 25

20 Fig. 11: Axial Contrast enhanced CT of abdomen showing hepatic abscess with extra hepatic extension into the retroperitoneum. Patient subsequently was diagnosed to have IE on Echocardiogram Fig. 14: (A) Axial and sagittal Post contrast CT images showing left femoral vein DVT with superimposed infection seen as gas locules in the left femoral vein in a patient with known IV drug abuse. Page 20 of 25

21 Fig. 9: Sagittal (A) and Axial (B) contrast enhanced CT scan showing splenic abscess. Page 21 of 25

22 Fig. 13: Same patient as figure (12),Axial T1 fat suppressed post gadolinium sequences, showing a small right paravertebral abscess collection secondary to discitis (arrows). Page 22 of 25

23 Fig. 6: Axial contrast enhanced CT Pulmonary angiogram showing an aberrant filling defect in the left ventricles (arrow) suggestive of a vegetation/ thrombus confirmed on an Echocardiogram in a patient with IE. Page 23 of 25

24 Fig. 12: Sagittal T2 (A) and Sagittal STIR (B)MRI images illustrating mid thoracic discitis seen as abnormal high signal change in the disc and STIR sequences showing the high marrow signal in adjacent vertebral bodies. Note the small epidural abscess (Black arrow). Page 24 of 25

25 Conclusion Infective endocarditic is a potentially life threatening disease with associated mortality. Although echocardiography remains to be the gold standard in the diagnosis of IE, many extracardiac radiological imaging features offer invaluable clues that aids in prompt diagnosis and effective treatment. Personal information References C. Prados, C. Carpio, A. Santiago, I. Silva and R. Álvarez-Sala (2012). Radiology in Infective Endocarditis, Endocarditis, Prof. Francisco Ramón Breijo-Márquez (Ed.), ISBN: Colen TW,Gunn M, Cook E, Dubinsky T, Radiological Manifestations of Extra-cardiac complications of infective endocarditic: Eur Radiol.2008 Nov;18 (11): Doi: /s Epub 2008 jun 4. Davidson, principles and practice of medicine, 19th edition. Page 25 of 25