Changing Etiology of Bacteremia in Patients with Hematological Malignancies in Denmark

Abstract

To ascertain whether the microbiological etiology of bacteremia among patients with hematological malignancies has changed in Denmark, the species distribution of clinically relevant blood culture isolates from the Hematological Department at Rigshospitalet, Copenhagen in 1990 was compared with 2 previous studies (1970-72; 1981-85). In addition, time trends of the etiology of bacteremia among hematological patients in Copenhagen (eastern Denmark) and in Arhus (western Denmark) were compared. In contrast to many other studies, a significant increase in the proportion of Gram-negative aerobes was observed in Copenhagen (from 43% in 1981-85 to 55% in 1990; p < 0.05), whereas in Arhus the proportion of Gram-positive aerobes increased steadily during the 1980s (from 34% to 51%; p < 0.05). In Copenhagen, non-hemolytic streptococci and Xanthomonas maltophilia increased significantly and accounted for 10% (p < 0.01) and 5% (p < 0.05) respectively, of all isolates in 1990, whereas Staphylococcus aureus during the 2 decades studied decreased from 25% to 8% (p < 0.001). In both regions, a decrease was observed in the proportion of Pseudomonas aeruginosa which accounted for only about 5% of all isolates in 1990. No changes were observed in the rates of anaerobes and yeasts. Several factors may contribute to the reported differences in the etiology of bacteremia among hematological patients, e.g. criteria used to assign the clinical significance of the isolate, blood culture system used, practice of using indwelling intravenous catheters, different policies with respect to antimicrobial treatment, and the degree of immunosuppression. A local surveillance of blood culture isolates is mandatory if changes in etiology and resistance development are to be detected.

Frequency of Blood Culture Isolates and their Antibiogram in a Teaching Hospital

“…Knowledge of the hospital epidemiology and antimicrobial resistance pattern of blood isolates helps physicians to effectively manage bloodstream infections. 11 In the present study, 13.3% of the total sample comprised the culture positivity, which is very close to the finding of study done in Kuala Lumpurl. 8 However, different studies have reported variable results (10.23% -45.9%) [9][10][11][12] which can be due to reasons like different methods of blood culture, administration of prior antibiotics, and infection with anaerobes or effective control in spread of nosocomial infection.…”

Secular trends of antimicrobial resistance of blood isolates in a newly founded Greek hospital

“…Knowledge of the hospital epidemiology and antimicrobial susceptibility pattern of blood isolates helps physicians to effectively manage blood stream infections. This is because considerable differences of the frequency of blood isolates are reported even from hospitals of similar size and mixture of patients of the same country [ 6 ].…”

Microbiological and Clinical Aspects of Infection Associated with Stenotrophomonas maltophilia

“…Bacteremia may be secondary to a pulmonary, urinary, or gastrointestinal source (8,388,467,470) although it is often not possible to determine the portal of entry. The importance of intravascular devices in the pathogenesis of S. maltophilia bacteremia is, however, becoming increasingly recognized (10,28,78,115,116,138,279,284,432), and in cases where there is no obvious source of infection it has been suggested that these devices may be the primary source. For example, Muder et al report that in their series of 91 patients with S. maltophilia bacteremia, 56% did not have a clinically apparent portal of entry but 84% of these individuals had a central venous catheter in place (284).…”