PROSPECTIVE MULTICENTRIC STUDY OF THE ETIOLOGY OF 1051 BACTEREMIC EPISODES IN 782 CANCER-PATIENTS

A total of 1051 bacteremic episodes (782 patients) were prospectively recorded in 10 cancer centers (9 French, 1 Belgian), with: patient's a ge (mean 53, range 1-89 years), underlying cancer, neutropenia (< 1000 neutrophils/mul; 233), signs and symptoms, type of i.v. line (percuta neous central: 534; peripheral: 228; central implanted: 304), treatmen t, blood culture system, number of positive blood culture bottles/tota l obtained, time to growth. Of all episodes, 23.2% occurred within 48 h of admission. The patients were receiving systemic antibiotics at sa mpling (on AB) in 34.6% of cases. The 1147 pathogens isolated (86 poly microbial) were: E. coli (10.70%), Klebsiella-Enterobacter-Serratia (6 .1%), other enterobacteriaceae (2.2%), Pseudomonas aeruginosa (4.8%), other nonfermenters (4.7%), coagulase-negative staphylococci (CNS, 40. 8%), Staphylococcus aureus (9.9%), streptococci (5.4%), enterococci (2 .2%), anaerobes (3.4%), yeasts (3.5%), and other bacteria (6.9%). The CDC (Centers for Disease Control) criteria (1988) were used to assess significance: group 1: pathogenic species (616 episodes; 59%); group 2 : clinical signs and isolation of a 'contaminant'' species (47; 4.5%); group 3: as in group 2 with an i.v. line and empiric antibiotic treat ment (181 episodes including 176 CNS; 17%); group 4: non-significant ( 207 episodes including 203 CNS; 20%). Groups 1-3, in which the episode s were considered to be significant (844 episodes; 80%) were compared with non-significant episodes (Fisher). Significant differences (P les s-than-or-equal-to 0.05) were seen in time to growth (median growth wi thin 24 h vs 48 h), fever (86% vs 54%), chills (40% vs 3%), hypotensio n (10% vs 20%), septic shock (9% vs 1%), polymicrobial etiology (10% v s 0.5%), and initiation of empiric antibiotic treatment (71% vs 4%). B acteremic episodes of CDC groups 1, 3 and 4 were further studied in ep isodes with a single isolate as a doubtful clinical significance (482 episodes) and episodes with greater-than-or-equal-to 2 bottles positiv e of probable clinical significance (569 episodes; 54%). In group 1 (2 18 doubtful, 398 probably significant episodes) significant difference s were seen in chills (36% vs 52%), shock (7% vs 13%), polymicrobial ( 8% vs 17%), initiation of empiric antibiotic treatment (60% vs 72%); i n group 3 (87 doubtful, 94 probably significant) in time to growth del ay; in group 4 (177 doubtful, 30 probably significant) in proportion w ith implanted catheter (26% vs 52%), fever (62% vs 10%), and time to g rowth. This study confirms the predominant role of Gram-positive cocci in bacteremia occurring in cancer patients.