Antibiotic prophylaxis and prosthetic valve endocarditis.

Early onset prosthetic valve endocarditis is one of the most lethal complications after valve replacement. During the first year of operation of our new cardiac surgical program, we observed 10 cases of prosthetic valve endocarditis, the majority being caused by staphylococci, making an incidence of 10.6%. Subsequent investigations uncovered a very high prevalence of methicillin-resistant strains which led to a radical change in the antibiotic prophylaxis, from a cephalosporin-based protocol to a two drug regime of vancomycin and netilmicin. There were no cases of prosthetic infection among the 138 patients operated on in the one year period following the institution of this protocol. Because there were no other changes, either in the types of prostheses used or the techniques of implantation, the eradication of prosthetic valve endocarditis can be related only to this alteration in the prophylaxis. Therefore, we may conclude that the inter-institutional transfer of protocols is not adequate before a thorough investigation of the prevalent hospital pathogens and their sensitivity to antibiotics is carried out. We have not registered resistances to vancomycin and this drug remains the most important antimicrobial agent, both in the prophylaxis and in the treatment of prosthetic valve endocarditis.     

Salmonella prosthetic valve endocarditis

We report the case of a 69-year-old man with an aortic valve bioprosthesis in whom a diagnosis of Salmonella typhimurium prosthetic valve endocarditis was made. During the prolonged hospital admission early aggressive antibiotic therapy and early valve replacement surgery were the deciding factors enabling him to survive this otherwise lethal condition.     

Infective endocarditis affecting the eustachian valve.

A previously fit 44 year old man presented with acute staphylococcal pneumonia. Despite appropriate antibiotics he showed signs of continuing sepsis and eventually died. At necropsy endocarditis of the eustachian valve was found.     

A crusty cause of prosthetic valve endocarditis.

A 73-year-old man with two previous mitral valve replacements presented with prosthetic valve infective endocarditis. Ten days before hospitalization he had undergone minimally invasive cutaneous surgery for crusty lesions but had not received antibiotic prophylaxis. The current literature regarding the role of antibiotic prophylaxis in dermatological procedures is discussed along with the issues surrounding this patient.     

Actinobacillus actinomycetemcomitans prosthetic valve endocarditis

Actinobacillus actinomycetemcomitans, a fastidious gram-negative bacillus, has been reported as the cause of prosthetic valve endocarditis in 11 patients. Two additional patients are reported and the literature is reviewed. All cases occurred greater than 1 year after implantation of the prosthesis. Six of the 13 patients had had recent dental work or had poor dentition. Three patients had received endocarditis prophylaxis. Ten of 13 were cured with antibiotics alone. Only one patient suffered from congestive heart failure, and only one had documented evidence of major systemic emboli during antimicrobial therapy. Valve replacement was necessary in only two during antimicrobial therapy. A actinomycetemcomitans should be considered as a possible etiologic agent in late prosthetic valve endocarditis, particularly when blood cultures are initially negative. A regimen of a beta-lactam antibiotic in combination with an aminoglycoside is recommended for 4-6 weeks. The excellent in vitro activity of the third-generation cephalosporins and rifampin promise new therapeutic options.     

Legionella micdadei prosthetic valve endocarditis

Summary Legionella usually causes pneumonia, but occasionally is in the differential diagnosis of culture negative endocarditis which sometimes involves prosthetic heart valves.Legionella prosthetic valve endocarditis is nearly always due toLegionella pneumophila and its clinical presentation is indistinguishable from other causes of prosthetic valve endocarditis. Diagnosis ofLegionella prosthetic valve endocarditis is by recovery of the organism from the blood, demonstration or isolation of the organism from the prosthetic heart valve, or by persistently highLegionella titers which are extremely elevated in prosthetic valve endocarditis compared toLegionella pneumonia. We believe this is the first case reported of prosthetic valve endocarditis caused byLegionella micdadei, and the first case ofLegionella prosthetic valve endocarditis with microscopic hematuria.

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Klappenprothesenendokarditis durchLegionella micdadei

Zusammenfassung Gelegentlich muß der PneumonieerregerLegionella in der Differentialdiagnose der kulturnegativen Endokarditis berücksichtigt werden, die manchmal auch Klappenprothesen befällt. Die Klappenprothesenendokarditis wird bei Legionellenätiologie fast ausschließlich durchLegionella pneumophila verursacht; in ihrem klinischen Erscheinungsbild ist sie von Klappenprothesenendokarditiden anderer Genese nicht zu unterscheiden. Die Diagnose wird durch Erregernachweis im But, in der entfernten Klappe oder durch sehr hoheLegionella-Titer nachgewiesen, die im Vergleich zur Legionellenpneumonie extrem stark erhöht sind. Wir gehen davon aus, daß unsere Fallmitteilung die erste Publikation einer Klappenprothesenendokarditis durchLegionella micdadei und der erste Fall mit Mikrohämaturie ist.

     

Haemophilus paraphrophilus prosthetic valve endocarditis

We report a case of prosthetic, aortic valve, infective endocarditis caused by Haemophilus paraphrophilus. There are no other cases described in the available literature where this microorganism has caused prosthetic valve endocarditis and no other case reported involving only the aortic valve.     

Candida albicans prosthetic valve endocarditis. Two cases

TWO CASES: Candida albicans prosthetic valve endocarditis (PVE) is a rare entity with serious complications. We report two cases of Candida albicans PVE, confirmed by culture of the prosthetic valve. The first patient died twenty days after surgery with cerebral bleeding secondary to multiple mycotic aneurysms, the second patient was still alive eight months following a Saint-Jude aortic valve replacement and prolonged antifungal therapy. The difficulty of diagnosis and management are discussed.     

Management of prosthetic valve infective endocarditis

This study analyzed the profile and outcome of surgically versus medically treated patients with prosthetic valve infective endocarditis (PVE). From 2000 to 2006, 80 patients >16 years of age (median 71) with definite PVE according to modified Duke criteria were included. The medically treated group was separated into deliberately conservative and perforce conservative treatments, the latter group including patients with contraindications to a cardiosurgical intervention. The most frequent causative micro-organisms were staphylococci. Forty-six percent of patients were surgically treated, 34% had deliberately conservative treatment, and 20% had perforce conservative treatment. Six-month mortality was 29%; 27% of surgically treated patients died, 4% deliberately conservatively patients died, and 75% perforce conservatively treated patients died. Septic shock, multiorgan failure, and type of treatment were significantly associated with death in univariable analysis. Multivariable analysis revealed that type of treatment (perforce conservative) and septic shock predicted death in patients with PVE. Survival was most favorable in deliberately conservatively treated patients, including PVE due to Staphylococcus aureus. In conclusion, there remains a role for watchful waiting in patients with PVE without evidence of major complications. Moreover, patients with uncomplicated S. aureus PVE can be treated successfully without cardiac surgery. Conversely, patients with major complicated PVE should preferentially undergo surgery. Predictors of mortality in patients with PVE included septic shock and perforce conservative treatment.