Lecythophora mutabilis prosthetic valve endocarditis in a diabetic patient.

While dematiaceous (dark-walled) fungi are ubiquitous in the environment, their involvement in invasive human infections has rarely been reported. However, these organisms have been identified as potential emerging pathogens, particularly among immunocompromised hosts. We describe a diabetic patient with Lecythophora mutabilis prosthetic valve endocarditis who was treated surgically, as well as with amphotericin B lipid complex and voriconazole, which were subsequently followed by prolonged voriconazole suppressive therapy. To the best of our knowledge, our patient is the first reported survivor of L. mutabilis prosthetic valve endocarditis.     

Long-term survival of a patient with prosthetic valve endocarditis due toTrichosporon beigelii

A case is described of a 49-year-old man with rheumatic aortic valve disease who developed endocarditis seven years after valvular replacement.Trichosporon beigelii was isolated from the blood, a peripheral thrombus, and the removed prothesis. After two valve prosthesis replacements and prolonged antifungal therapy, the patient survived for four years, but eventually died as a consequence of multiple septic complications due to the same organism. To the authors' knowledge, this is the longest survival time of any reported case ofTrichosporon prosthetic valve endocarditis.     

Bacillus licheniformis prosthetic aortic valve endocarditis.

A 73-year old man developed an acute prosthetic aortic valve dehiscence for which emergent operation was undertaken. The intraoperative evidence of an aortic annular disruption and of a subannular abscess led to the hypothesis that an endocarditis process was involved. The aortic valve was replaced with a stentless porcine bioprosthesis. Cultures taken intraoperatively from the aortic area had a pure growth of aerobic, spore-forming, gram-positive bacilli identified as Bacillus licheniformis. The patient responded to specific antibiotic therapy with no relapse at a 20-month follow-up. The potentiality of B. licheniformis as a pathogen should be reconsidered.     

Case report of Streptomyces endocarditis of a prosthetic aortic valve.

We describe the first case of prosthetic valve endocarditis due to a Streptomyces sp. The patient presented with fever, cutaneous embolic lesions, and bacteremia 3 months after aortic valve replacement. Treatment required valve replacement and a long course of parenteral imipenem.     

Q fever endocarditis associated with a cardiovascular implantable electronic device

Cardiovascular implantable electronic devices (CIEDs) are frequently related to endocarditis. Most cases of intravascular CIED infections are usually related to skin flora, but a few cases may occur with negative blood culture. Coxiella burnetii is one of the main causes of blood culture-negative endocarditis in native and prosthetic valves, but to date no cases related to CIED have been published. Herein we report two cases of Q fever endocarditis related to these non-valvular cardiovascular devices.     

Relapse of Enterococcus hirae prosthetic valve endocarditis

Enterococcus hirae, a gram-positive bacterium, is a rare isolate in clinical specimens. We report an unusual case of a relapse of prosthetic valve endocarditis due to E. hirae 6 months after the initial episode. Clonal relationship was proven by genomic analysis.     

Paecilomyces javanicus endocarditis of native and prosthetic aortic valve

A 41-year-old diabetic woman developed endocarditis of the aortic valve caused by Paecilomyces javanicus six years after insertion of a porcine mitral valve heterograft. The patient died shortly after aortic valve replacement. Autopsy revealed vegetations of the aortic heterograft, valve ring abscess and ascending aortitis due to Paecilomyces. There was no involvement of the mitral valve heterograft. Lesions due to mycotic emboli were found in the kidneys, spleen, and brain. Cultures of the surgically removed aortic valve and of the kidney at autopsy produced rapid growth of P. javanicus. The gross and microscopic pathologic and cultural characteristics of this organism are described with a review of the literature. Previously reported cases of Paecilomyces endocarditis occurred only in prosthetic heart valves. This is the first known report of P. javanicus endocarditis of a native valve and its prosthetic heart valve heterograft.     

CD4+ T-cell lymphopenia in Q fever endocarditis.

Valvular endocarditis is the most serious complication of chronic Q fever, an infectious disease due to Coxiella burnetii. Although its pathogenesis is poorly understood, the role of the immune system has been evoked. The aim of this study was to investigate lymphocyte subsets in the peripheral blood of infected patients by analyzing the distribution of T- and B-lymphocyte subsets. Since various infectious diseases have been found to be associated with modified antigen expression, we also measured the antigen density of the main lymphocyte markers by quantitative flow cytometry. The absolute values of CD3+ T cells and CD19+ B cells were lower in infected subjects than in controls. The decrease in the CD4+ T-cell count was more pronounced than that in the CD8+ T-cell count, leading to a significantly lower CD4/CD8 ratio in patients. The decreases in CD4+ T cells and CD19+ B cells were correlated with levels of C. burnetii-specific immunoglobulin G, showing that CD4+ lymphopenia is related to the activity of chronic Q fever. Quantitation of antigen expression on lymphocytes showed that CD3, CD4, CD8, and CD19 were expressed similarly in patients and controls. In contrast, CD2 and CD11a expression levels, which are both related to naive and memory phenotypes, were modified in patients. The study of CD45RO and CD45RA expression by CD4+ T cells provided evidence that lymphopenia preferentially affected unprimed lymphocytes.     

Plasmid pattern analysis of Staphylococcal epidermidis isolates from patients with prosthetic valve endocarditis.

The electrophoretic pattern formed by individual bacterial plasmid DNA molecules of differing molecular size was evaluated as an epidemiological marker among isolates of Staphylococcus epidermidis from patients with prosthetic valve endocarditis (PVE). Purified covalently closed circular plasmid DNA was obtained from selected isolates, and 79% of the plasmids were found to be less than 10 megadaltons in size; only these small plasmids were sought in subsequent screening gels. Crude cell lysates obtained by a rapid lysis technique and screened by agarose gel electrophoresis revealed the presence of one or more small plasmids in 54 of 58 (93%) PVE isolates; 79% contained two or more. Among 45 plasmid-containing isolates from cases of sporadic PVE at three institutions there were no identical plasmid patterns, although several isolates differed by a single plasmid. In contrast, among nine isolates from a cluster of cases of PVE in Canada, two groups of three isolates each had identical plasmid patterns. Additional clinical data suggested that these isolates were epidemiologically related. Phage typing distinguished one of the groups with plasmid pattern identity, but not the other, from the three isolates with dissimilar patterns. Plasmid pattern analysis shows promise as an epidemiological marker for clinically important isolates of S. epidermidis.     

Phenotypic variation of Staphylococcus epidermidis isolated from a patient with native valve endocarditis.

Two colonial variants of Staphylococcus epidermidis were isolated from the valvular tissue of a patient with native valve endocarditis. In addition to differing in colonial morphology, the two variants differed in hemolysis on blood-containing media, in adherence capacity, and in the expression of certain enzymes. Under suitable conditions, both variants were themselves capable of phenotypic variation, although they differed in the rate at which variants were generated. The variants yielded identical profiles on restriction endonuclease analysis of plasmid DNA and pulsed-field gel electrophoresis of whole-cell DNA. This report suggests a possible role for phenotypic variation in coagulase-negative staphylococcal virulence. Congo red agar would be an excellent medium for studying the contribution of variation to the virulence of these organisms.     

Capnocytophaga canimorsus: a rare case of conservatively treated prosthetic valve endocarditis

We describe a rare case of prosthetic valve endocarditis caused by the canine bacterium Capnocytophaga canimorsus in a male aged 73 years. The diagnosis of infective endocarditis was unequivocal, as it blood cultures were positive for C. canimorsus and vegetations were detected on transesophageal echocardiography; the modified Duke criteria were fulfilled. PET‐CT showed intense ¹⁸F‐FDG uptake of the prosthetic valve area. The patient was treated with antibiotics alone (no surgery), and is now on life‐long suppressive antibiotic therapy. To our knowledge, this is the third reported case of prosthetic valve endocarditis caused by C. canimorsus and the first one to have been treated conservatively.     

Histoplasma capsulatum prosthetic valve endocarditis with negative fungal blood cultures and negative histoplasma antigen assay in an immunocompetent patient

We report a case of Histoplasma capsulatum endocarditis in which Histoplasma antigen assay and fungal blood cultures were negative. The diagnosis was made by microscopic examination and culture of the excised valve. Histoplasma capsulatum should be considered in the differential diagnosis of culture-negative endocarditis in regions where it is endemic and in travelers.     

Prosthetic valve endocarditis caused by Corynebacterium diphtheriae in a patient with pemphigus vulgaris.

The clinical and bacteriological findings in a case of prosthetic aortic valve endocarditis caused by Corynebacterium diphtheriae are presented. The patient died despite adequate medical therapy. This appears to be the first report of endocarditis caused by this species in a prosthetic aortic valve.     

First isolation of Bartonella alsatica from a valve of a patient with endocarditis

We report the first documented case of endocarditis in a man infected with Bartonella alsatica, which causes bacteremia in healthy wild rabbits. B. alsatica was identified by serology and culture and by PCR of an aortic valve specimen. B. alsatica should be added to the list of zoonotic agents of blood culture-negative endocarditis.     

Scanning electron microscopy examination of a porous alumina prosthetic heart valve

Scanning electron microscopy has been used to examine the porous alumina body of a novel prosthetic heart valve after experimental implantation in a pig. Characteristic features of this unusual material were observed and the biological surface covering resulting from implantation was identified.     

Serological differentiation between acute (late control) and endocarditis Q fever.

AIMS--To differentiate the serological profiles of chronic (endocarditis) Q fever from the late follow up of acute cases. METHODS--Twenty patients (10 diagnosed with acute and 10 with endocarditis Q fever) were studied. Those diagnosed with acute infection were followed up from 2.5 to 88 months (mean 35.8 months). Serological variables included indirect immunofluorescence against phase I and II of Coxiella burnetii (IgM, IgG, and IgA), complement fixation and rheumatoid factor (RF). RESULTS--All patients with titres of IgA against phase I, after IgG removal, equal to or above 320 and a complement fixation value equal to or above 128 had endocarditis. No patient with acute Q fever had such a serological profile. CONCLUSIONS--The combination of IgA against phase I and complement fixation values may be sufficient to differentiate the serological profile of chronic (endocarditis) Q fever from the late follow up of acute cases.     

Native valve Bacillus cereus endocarditis in a non-intravenous-drug-abusing patient

Bacillus cereus is a rare cause of endocarditis, typically associated with intravenous drug abuse, rheumatic heart disease, prosthetic heart valves, pacemakers, or immunodeficiency. We present the first case of native valve Bacillus cereus endocarditis with no apparent risk factors. The patient had a fulminant course requiring emergent valve replacement.