[Mitral valve endocarditis caused by Erysipelothrix rhusiopathiae]. / Mitralklappenendokarditis durch Erysipelothrix rhusiopathiae.

HISTORY AND CLINICAL FINDINGS: A 67 year-old country woman was admitted to the hospital because of a four weeks history of continuous catarrh, arthralgia and fever. Recently, she had also developed upper abdominal pain after oral ibuprofen treatment. The clinical examination showed a patient of impaired general condition. The heart and lungs were auscultatory normal and there were no signs of dyspnea, cyanosis or inflammatory skin lesions. EXAMINATIONS: Physical examination of heart and lung, electrocardiography and transthoracic echocardiography were without pathological findings. CLINICAL COURSE: Gastroscopy revealed acute antral gastritis and duodenitis with presence of Helicobacter pylori. Eradication therapy resolved the abdominal symptoms but fever returned after the antibiotic therapy was stopped. The patient developed a severe endocarditis with progressive mitral regurgitation within a few days. Erysipelothrix rhusiopathiae was isolated from blood cultures and identified by conventional and molecular methods. The patient was treated successfully with 3 x 2 g ampicillin daily, applied parenterally for six weeks, and a mitral valve replacement. CONCLUSION: This was an unusual manifestation of systemic Erysipelothrix rhusiopathiae infection. The bacterium Erysipelothrix rhusiopathiae has still to be considered in the diagnosis and treatment of endocarditis in patients with increased risk of exposure (e.g. farmers, butchers and fishermen).

On-line analysis of electrolytes in extracorporeally circulating blood: application of a rat model to examine the effect of a single pharmacological dose of melatonin on electrolyte levels in blood.

An experimental model was developed to study the kinetics of electrolytes under different physiological and/or pathological conditions. The model was applied to investigate in vivo the effect of a pharmacological dose of melatonin on the concentrations of Ca2+, K+, Na+, and pH in the anticoagulated blood of anaesthetized male Wistar rats (250-350 g). After the application of 0.25 mg melatonin/kg body weight, injected intraperitoneally into each of 8 rats, the electrolytes were measured by a flow-through system with highly sensitive ion-selective electrodes. The results were compared to a control group (n=8) which was treated with diluent (saline). The electrolytes were monitored continuously via an extracorporeal circulation, on-going for at least 60 min. Melatonin induced a significant increase of blood Ca2+ (p<0.02) by an average of 9.9% after 60 min. However, total calcium concentration did not increase significantly. The extracorporeal circulation provoked an elevation of K+ by hemolysis. This K+ increase was slightly diminished by melatonin (p<0.06). No melatonin effects were seen on Na+, pH and magnesium in blood and plasma, respectively. Also, the urine concentrations of the electrolytes were not altered by melatonin. The mechanism by which melatonin influences the blood concentrations of ionized calcium and potassium is not yet understood.

Continuous analysis in extracorporeally circulating blood--a rat model applying flow-through ion-selective electrodes for the measurement of Ca2+, K+, Na+ and pH.

A rat model is introduced which enables investigations in anticoagulated blood with continuous measurements by a flow-through electrode system. In the present study, a potentiometric ion-selective electrode (ISE)-system was used for measuring Ca2+, K+, Na+ and pH in rats. The setup was adjusted to an extracorporeal blood-volume of 0.750 ml. This permits indirect measurements of the analytes via a dialysis membrane, with electrical separation of the ISE's and the animal. The flow-rates of blood and dialysis-solution were adjusted in such a way that water diffusing from the aqueous dialysis solution into the blood, across the dialysis membrane, does not alter the haematocrit. Polyethyleneglycol-hirudin was used for anticoagulation, since it was superior to heparin. The assembly enables continuous measurements in the living anaesthetized rat over a time period of at least 3 hours.