The Centers for Disease Control and Prevention (CDC) and National Healthcare Safety Network (NHSN) have developed surveillance definitions for health care-associated infection (HCAI) and specific types of infections in health care settings. The diagnosis of laboratory-confirmed bloodstream infection (LCBI) requires that certain criteria be met.
The presence of one or both of the following can be used to diagnose LCBI
(1) a recognized pathogen is cultured from one or more blood cultures
(2) all of the following:
(2a) 1 or more of the following:
(2a1) fever (> 38°C, rectal if <= 1 years)
(2a2) hypothermia if <= 1 year (rectal temperature < 37°C)
(2a3) apnea if <= 1 year of age
(2a4) bradycardia if <= 1 year of age
(2a5) chills
(2a6) hypotension
(2b) a recognized skin contaminant is cultured from 2 or more blood cultures drawn on separate occasions within a 48 hour period (within 2 days of each other)
(2c) not explained by an infection at another site
Common skin contaminants include:
(1) diphtheroids
(2) Bacillus species other than Bacillus anthracis
(3) Proprionibacterium species
(4) coagulase negative Staphylococci (S. epidermidis, others)
(5) viridans group Streptococci
(6) Aerococcus species
(7) Micrococcus species