Fungal Prosthetic Valve Endocarditis: Mayo Clinic Experience Including a Clinicopathologic Analysis
JM Boland, H Chung, FJL Robberts, WR Wilson, JM Steckelberg, KL Greason, LM Baddour, DV Miller. Mayo Clinic, Rochester, MN
Background: Fungal prosthetic valve endocarditis is a rare but devastating disease, which can lead to severe acute valve dysfunction. Data on this disease is sparse, with reports in the literature comprised largely of case reports and small series. In this study, we report an institutional experience of fungal prosthetic valve endocarditis with clinicopathologic analysis.
Design: To better characterize this rare syndrome, we retrospectively reviewed 21 cases of fungal prosthetic valve endocarditis seen at Mayo Clinic over the past 40 years.
Results: The average patient age was 65 years with a 2:1 male predominance. About half of the cases occurred within one year of prosthetic valve placement. The aortic valve was most commonly affected, and the most common etiologic organism was Candida species (16 cases), followed by Histoplasma capsulatum (3 cases). The majority of patients were immunocompetent, although they had other risk factors for fungal infection including recent cardiac surgery, antibiotic use, previous bacterial endocarditis, other systemic infections, and central venous catheters. Patients often presented with systemic signs and symptoms of infection, and cardiac imaging was abnormal in most cases. Pathological material was available on 12 of 21 cases (6 surgical specimens, 6 autopsies). Pathologic evaluation of valve material was high yield, with organisms identified in 92% of cases using H&E, GMS and/or PAS stains. The predominant histologic pattern was that of bulky fibrin and platelet-rich vegetations with scant to moderate associated mixed inflammation and necrotic debris. Some cases showed scattered giant cells, but well formed granulomas were not identified. Fungal prosthetic valve endocarditis was associated with a high morbidity and mortality, with 67% of patients experiencing complications and 57% of patients dying of infection-related disease.
Conclusions: Fungal prosthetic valve endocarditis is a rare but life threatening complication of valve replacement surgery, most commonly caused by Candida species. Most affected patients are immunocompetent, and can be affected any time after prosthetic valve placement. The aortic valve is most commonly involved, and vegetations are often bulky. Pathologic evaluation of valve material is high yield, with organisms identified in the vast majority of cases.
Wednesday, March 24, 2010 1:00 PM
Poster Session VI # 214, Wednesday Afternoon