Infective endocarditis. Diagnosis and management

Dermatologic Problems in the Intensive Care Unit: Part II

Skin disorders are present in many patients hospitalized in the intensive care unit. They range in severity from being the reason for admission to being a nuisance during care. These cutaneous problems have been categorized into four groups: (1) serious skin diseases that may incur life-threatening complications; (2) subtle skin problems associated with systemic disorders that may be characterized by critical events; (3) prominent cutaneous manifestations that accompany life-threatening systemic diseases; and (4) skin disorders that develop as complications during intensive care. Diseases in the first category were discussed in Part I of this article [1]. In Part II, we discuss diseases in the second category. The remaining disorders will be covered in Parts III and IV.

Right-side endocarditis in injection drug users: review of proposed mechanisms of pathogenesis

Infective endocarditis of the right-side heart valves occurs commonly in injection drug users. Although a variety of hypotheses have been put forward to explain this clinical observation, no single hypothesis is adequate. In this article, basic scientific, clinical, and microbiological data on this topic are presented. It is apparent that no clear unifying mechanism emerges to explain the well-documented clinical predilection for the infection of the right-side heart valves in this population. Further investigation of this topic utilizing large international clinical registries may help to clarify matters further.

Listeria monocytogenes endocarditis in a patient on chronic hemodialysis, successfully treated with vancomycin-gentamicin

A case of Listeria monocytogenes endocarditis occurring as a complication of a vascular access infection in a patient on chronic hemodialysis that was successfully treated with a combination of vancomycin and gentamicin is reported. The difficulties in the diagnosis and treatment of L. monocytogenes infections, especially endocarditis, in patients on chronic hemodialysis are discussed.

Intraocular lenses and experimental bacterial endophthalmitis

To determine if an intraocular lens renders bacterial endophthalmitis more resistant to therapy, an animal model was developed. Nine rabbits underwent bilateral extracapsular lens extraction with placement of a Simcoe posterior chamber IOL in one eye. Approximately 170 organisms of Staphylococcus aureus were inoculated into both eyes. The eyes of seen animals were treated with intravitreal and subconjunctival gentamicin after 24 and 48 hours. Vitreous cultures remained sterile in all treated eyes for one week after antibiotic therapy. Two animals that did not receive antibiotics showed persistent infection. There was no difference between aphakic and pseudophakic eyes in terms of clinical response or onset of negative cultures.

Treatment of pseudomonal endocarditis with high-dose aminoglycosides

High-dose aminoglycoside therapy (6–8 mg/kg/d) in an intravenous drug abuser with Pseudomonas aeruginosa endocarditis is described. The dose of tobramycin was adjusted to achieve peak serum concentrations of 15–20 μg/ml and trough concentrations of 〈 2 μg/ml. Significant drug-induced toxicities were not observed. Treatment of P. aeruginosa endocarditis with high-dose aminoglycosides may be appropriate and beneficial in selected patients.

Infectious endocarditis in idiopathic hypertrophic subaortic stenosis: report of three cases and review of the literature

Three cases of infective endocarditis (IE) occurringg in patients with idiopathic hypertrophic subaortic stenosis (IHSS) are described. A review of the literature reveals the IE occurs in about 50 percent of the patients suffering from IHSS. It appears to complicate the natural history of the severe cases, at least as it appears from hemodynamic studies, being precipitated by the same factors and caused by the same infective organisms as in valvular heart disease. It has the same clinical picture and outcome, although the appearance of new murmurs was more common than in other types of heart disease complicated by IE, and indicated the same poor prognosis. The infection seems to involve both the aortic and the mitral valve, with equal frequency, and less commonly the ventricular outflow tract. The need for IE prophylaxis in cases of IHSS is stressed.

The use of echocardiography in diagnosing culture-negative endocarditis

We reviewed M-mode and two-dimensional echocardiographic findings in 11 patients with abacteremic endocarditis to study the application of echocardiography in this setting. All patients had negative blood cultures but underwent surgery that confirmed the presence of active infective endocarditis. The infection involved native valves in five patients and prosthetic valves in six patients. Valvular masses were identified in eight patients. The other three patients, who had prosthetic aortic valves, had diastolic mitral valve vibration characteristic of aortic regurgitation. One of these also showed dehiscence of the prosthesis. Three patients had poorly defined clinical illnesses and echocardiography was a prime element in the diagnosis because valvular masses were identified. The operation was facilitated by knowledge of the mass indicated by echocardiography in these eight cases. Also, the surgical approach was affected by knowledge of dehiscence and perivalvular abscess formation in two cases each.

Staphylococcal septicaemia, endocarditis, and osteomyelitis in dialysis and renal transplant patients

Septicaemia is a common and potentially lethal hazard of haemodialysis and renal transplantation; it is usually caused by Staphylococcus pyogenes. In 6 patients with S. pyogenes septicaemia, fatal endocarditis and spinal osteomyelitis have each occurred once, and 3 patients have had recurrent episodes of septicaemia. The management of septicaemia in these patients must include a search for metastatic infection, and prolonged therapy with 2 antistaphylococcal agents is necessary to ensure eradication of infection. Access site infection in dialysis patients must be treated vigorously, and recognized as potentially hazardous by patients. The risk of sepsis in dialysis and transplant patients cannot be excluded, but devastating consequences may be avoided by simple measures.