A Clinical Study of Bacteremia in Urology

Abstract

We investigated 32 patients with bacteremia that occurred in the Department of Urology, School of Medicine, Kanazawa University between April, 1983 and March, 1989. This incidence represented 1.9% of the total number of inpatients. The study group comprised 29 males and 3 females, and their age varied from 25 to 82 years with a mean age of 61.7 years. Twenty-two (75%) of the 32 patients had urologic malignancies. The majority of patients were compromised hosts who had one or more (average, 3.8) factors that promoted bacteremia. Urinary tract infections existed in 26 (86.0%) patients before the bacteremic episode and urine cultures revealed a species identical to that simultaneously isolated from the blood in 19 (73.1%) of the 26 patients. Out of the 26 patients, there were 22 (84.6%) with complicated pyelonephritis and 22 (84.6%) with an indwelling urinary tract catheter. In blood cultures, the most common isolate was Staphylococcus epidermidis and gram-positive cocci were cultured at a rate of 43.9% which was higher than that (39.0%) of gram-negative rods. In contrast, in urine cultures, gram-negative rods were isolated predominantly. S. epidermidis and Corynebacterium spp. isolated less frequently in blood than in urine, indicated contaminants. However, Enterococcus spp. and Candida albicans were recognized as causative organisms of bacteremia via the urinary tract, because the urine culture demonstrated a species identical to that obtained from blood in these bacteremic patients. Antibiotic sensitivity tests demonstrated that isolates from blood tended to show tolerance to β-lactam antibiotics, but had good sensitivity to aminoglycosides.
Seven (22.5%) of the 16 patients who developed clinical septicemia died within a week after the bacteremic episode and 4 died before identification of the organism from blood. Out of the 4 patients, 3 were given inappropriate antibiotics and 2 showed serious drug-induced leukopenia. To improve the therapeutic results of septicemia in leukopenic patients, treatment with agents which raise the peripheral white blood cell count seems to be necessary in addition to the selection of appropriate antimicrobial chemotherapy.