The relevance of cultures of catheter-drawn blood and heparin-lock fluid to diagnose infection in hematologic patients

Abstract

The results of bacteriologic cultures of blood and heparin-lock fluid, both drawn from the central venous catheters of 54 consecutive oncohematologic patients, have been used to determine their value for the diagnosis of systemic and catheter-associated infection. In 30 patients with clinical signs of infection (bacteremia or septicemia), 74 of 1000 (7.4%) heparin-lock fluid cultures, 114 of 542 (21%) catheter-drawn blood cultures, and 36 of 134 (26%) venipuncture blood cultures became positive, whereas in 24 patients without clinical signs of infection the respective values were 5 of 700 (0.7%), one of 220 (0.4%), and none of ten cultures. Comparison of the results of cultures sampled on the same day reveals that the positive and negative predictive values for catheter-drawn blood cultures, with the venipuncture blood cultures taken as the standard for bacteremia, are 82% and 95% respectively. The results of heparin-lock fluid are indicative for clinically relevant colonization of the catheter. Three or more positive heparin-lock fluid cultures, sampled on subsequent days, were correlated with the occurrence of bacteremia or septicemia with a positive predictive value of 100%. The conclusions are supported by the results of scanning electron microscopy.

Infectious Complications of Central Venous Catheters Increase the Risk of Catheter-Related Thrombosis in Hematology Patients: A Prospective Study

“…All patients were treated according to a local protocol to prevent infections with aerobic Gram-negative rods, Viridans streptococci and Candida spp. 9 Prophylactic treatment included neomycin (250 mg), polymyxin B (1.10 6 U) orally qd, pipemidic acid 400 mg orally bid, and amphotericin B 200/10 mg qd. After 10 days of treatment, the dosage of the regime was reduced (half of the dosage in mg), except for the pipemidic acid.…”

Usefulness of endoluminal catheter colonization surveillance cultures to reduce catheter-related bloodstream infections in hemodialysis

“…15 Few studies have examined the usefulness of endoluminal surveillance culture (SC) to prevent CRBSI. 16,17 Heparin solution is commonly used to lock the catheter to prevent thrombosis, and there is some controversy over whether or not to include heparin in blood culture samples. Previous studies have shown no interference of heparin with the growth of microorganisms 18,19 and the usefulness of the blood-heparin mixture culture to predict CRBSI.…”