Prosthetic valve endocarditis: clinicopathological correlates in 122 surgical specimens from 116 patients (1985-2004).

Abstract

BACKGROUND:

Few studies have documented the clinicopathological features of prosthetic valve endocarditis independently of native valve endocarditis.

STUDY DESIGN:

Retrospective analysis of patients undergoing cardiac surgery for prosthetic valve endocarditis at our institution (1985-2004).

METHODS:

Medical records and microscopic slides were reviewed from 116 patients for demographics, infecting organisms, comorbidities, and pathologic features.

RESULTS:

Patients were 12-86 years old (mean, 59 years). Among 122 valves, 64% were from men and 67% were purely regurgitant. Aortic prosthetic valve endocarditis frequently affected men (76%); mitral prosthetic valve endocarditis often affected women (62%). Embolization occurred in 35% and heart failure in 32%. Prevalent predisposing conditions were the prosthetic valve alone (43%) and diabetes mellitus (20%). Prosthetic valve endocarditis was aortic or mitral in 98% and was active in 70%. Annular abscess or paravalvular leak affected mechanical valves more frequently than bioprosthetic (89% vs. 65%; P=.001). Causative organisms (n=116) included Staphylococcus aureus (30%), coagulase-negative staphylococcus (22%), viridans streptococci (18%), enterococci (10%), other streptococci (8%), and other organisms (12%). S. aureus was the most prevalent cause of early-onset (38%) and late-onset (30%) prosthetic valve endocarditis. Coagulase-negative staphylococcus caused early-onset (31%) and most intermediate-onset (40%) disease and had a shorter median implantation-to-infection time than other organisms (6.5 vs. 61.3 months; P<.001). Viridans streptococci and enterococci primarily caused late-onset endocarditis. For active infections by cocci, most cases exhibited strong Gram staining, but four showed only strong Grocott methenamine silver staining.

CONCLUSIONS:

Cocci accounted for 83% of infections. Early-onset prosthetic valve endocarditis was primarily staphylococcal, and late-onset prosthetic valve endocarditis resembled native valve endocarditis. Both Gram and Grocott methenamine silver stains were necessary to reliably identify organisms microscopically.

• Authors: Jonathan H Lee, Kimberly D Burner, Michael E Fealey, William D Edwards, Henry D Tazelaar, Thomas A Orszulak, Alan J Wright, Larry M Baddour
• Journal: Cardiovascular pathology : the official journal of the Society for Cardiovascular Pathology (Cardiovasc Pathol) 2011 Jan-Feb Vol. 20 Issue 1 Pg. 26-35 ISSN: 1879-1336 [Electronic] United States
• PMID: 19926308 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
• Copyright: Copyright © 2011 Elsevier Inc. All rights reserved.

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Aortic Valve
• Child
• Endocarditis (etiology, microbiology, pathology)
• Endocarditis, Bacterial (etiology, microbiology, pathology)
• Female
• Heart Valve Prosthesis (adverse effects, microbiology)
• Humans
• Male
• Middle Aged
• Mitral Valve
• Pulmonary Valve
• Staphylococcal Infections (etiology, microbiology, pathology)
• Streptococcal Infections (etiology, microbiology, pathology)
• Time Factors
• Young Adult