ASSESSMENT OF CLINICAL-SIGNIFICANCE OF POSITIVE BLOOD CULTURES OF RELATIVELY LOW-VIRULENCE ISOLATES

In Omori Hospital, Toho University School of Medicine, relatively low- virulence blood isolates, including coagulase-negative staphylococci ( CNS), enterococci and nonfermentative gram-negative rods other than Ps eudomonas aeruginosa comprised c. 60% of total blood isolates. A retro spective study was conducted to assess their clinical significance by reviewing a total of 91 hospital charts. The physicians' assessments o f these positive blood cultures as recorded in the charts were classif ied into four categories-sepsis, possible sepsis, contamination and no comment. The episodes classified as sepsis accounted for 5.0-19.6%. T hese episodes were also evaluated by a graded clinical significance sc ore based on multiple factors, including number of positive cultures a nd clinical signs. The scores for the 98 episodes covered a wide range from 1 to 9, indicating that both contaminants and causative organism s may have been involved. The episodes judged as sepsis or possible se psis tended to have higher scores. The scores for the episodes associa ted with enterococci were also higher than those involving CNS or non- fermentative gram-negative rods. The scores for episodes associated wi th intravenous hyperalimentation catheters were higher than those not associated with the catheters.