Two blood culture sets were collected from an adult. One bottle in one set grows a common skin commensal, while all bottles in the second set remain negative and the clinical picture does not support bacteremia. What is the best laboratory interpretation?
1Definite polymicrobial bacteremia with a skin commensal and a fastidious anaerobe, likely from a contaminated draw site during collection
2Possible collection contamination that should be assessed with the clinical context and contamination-monitoring criteria✓ 정답
3A false-negative Gram stain caused by excessive blood volume in the aerobic bottle, leading to missed organisms on initial examination
4Proof that the second set was collected after antibiotics were administered, suppressing growth of the organisms
해설
Growth of a common skin commensal in only one of multiple sets often represents contamination, especially when the clinical picture is discordant. The result still requires clinical correlation and application of the laboratory's defined contamination criteria.