The effect of ceftriaxone on the anaerobic bacterial flora and the bacterial enzymatic activity in the intestinal tract.

The normal flora of the intestinal tract, mainly consisting of anaerobic bacteria, protects the host against colonization by pathogenic microorganisms. Antimicrobial treatment with ceftriaxone may influence the colonic microflora and as a consequence, the protective effect. Ten healthy volunteers received 1 g of ceftriaxone intramuscularly for five days. This resulted in a significant decrease (p less than 0.05) of the mean cultural counts (+/- SEM) of total anaerobes from 10.67 (0.11) (prior to treatment) to 9.02 (0.45) and 8.97 (0.46) at days 3 and 5, respectively (during treatment). After treatment (days 10 and 15-19), the cultural counts of anaerobes returned to 10.17 (0.16) and 10.44 (0.18), respectively. Bacterial enzymes may serve as an indicator of protective microflora. beta- aspartylpeptidase and deoxycholate hydrolase activity was determined in faecal supernatants of the volunteers and compared with anaerobic culturing. Both enzymatic activities show a significant correlation with the total number of anaerobes present at day 3 of deftriaxone treatment. At day 5 and 8 only beta-aspartylpeptidase showed significant correlations with cultural counts of total anaerobes, Bacteroides spp. or bifidobacteria. At day 15 to 19 (ten to 14 days after treatment) beta-aspartylpeptidase showed only a significant correlation with the number of Bacteroides spp. This indicates that changes in the indigenous bacterial flora during and shortly after treatment with ceftriaxone can be monitored by determination of beta-aspartylpeptidase. Recovery of the intestinal flora is difficult to assess in this manner.

[Metabolism of myocardial catecholamines and plasma catecholamine levels in patients with chronic aortic regurgitation (author's transl)]. / Veränderungen des myokardialen Katecholamin-Stoffwechsels und Verhalten der Plasma-Katecholamine bei Patienten mit chronischer Aorteninsuffizienz.

In 17 patients suffering from severe chronic aortic regurgitation (class III N.Y.H.A.), during aortic valve replacement right atrial biopsies were taken. In these samples myocardial content of norepinephrine, normetanephrine, epinephrine and dopamine were determined. 2-4 days before valve replacement, plasma catecholamines were measured at rest and during isometric exercise. 15 patients with atrial septum defect (foramen secundum) served as controls. In patients with aortic regurgitation demonstrating no clinical signs of cardiac failure, myocardial content of norepinephrine, normetanephrine and epinephrine was significantly reduced compared to tissue content of patients with atrial septum defect. Right atrial content of dopamine did not reveal any difference between the two groups. In all patients, plasma catecholamines at rest were within normal limits. During isometric exercise, however, the increase of plasma norepinephrine in patients with aortic regurgitation was significantly higher compared to the control group. It is concluded from these data that patients with aortic regurgitation, demonstrating an exaggerated increase in sympathetic activity during exercise, probably show a decrease in myocardial norepinephrine tissue content. Therefore, clinical demonstration of hyperadrenergic response during exercise represents a simple metabolic parameter indicating alteration in myocardial metabolism in patients with chronic aortic incompetence. Since decision for aortic valve replacement should be done before irreversible damage of myocardium has established, it is supposed that assessment of sympathetic activity, at rest and during exercise, may reveal practical clinical importance.