Reading results

How to read blood culture results

Other platforms explain it with text and video. In VMS you practice it on the patient.

MD / DOPANursing (NCLEX)
Practice it in VR with Blocky

Blood cultures find bacteria and yeast in the blood and guide antibiotic choice. Reading early reports correctly avoids both missed infections and needless antibiotics.

Step by step

  1. Collect correctly

    Draw two sets from two different sites, ideally before antibiotics, with careful skin cleaning. Do not delay antibiotics in septic shock. [1]

  2. Read the Gram stain

    The first report gives shape and stain: gram-positive cocci in clusters (often staph), in chains (often strep), gram-negative rods, or yeast. [2]

  3. Spot likely contaminants

    Skin bacteria such as coagulase-negative staph, Cutibacterium or Corynebacterium in only one of two sets are often contamination. [2]

  4. Always treat some organisms

    Staph aureus, gram-negative rods and yeast are never treated as contaminants. Staph aureus needs repeat cultures and a heart ultrasound. [2]

  5. Report quickly

    A positive culture is a critical result. Tell the responsible clinician at once and document the time. [3]

  6. Narrow the antibiotics

    When the organism and susceptibilities return, switch to the narrowest effective antibiotic. [2]

  7. Repeat when needed

    Repeat cultures to confirm clearance for staph aureus and yeast. A final report of no growth comes after about 5 days. [4]

Common errors

Practice it in VMS

In VMS you do this on the patient, not on paper: every step goes on the checklist with a score, and in Teach mode Blocky tells you what comes next.

VMS cases that train this skill

84 VMS cases train this skill: open the case library

Sources

  1. Open RN, Nursing Skills 2e (Chippewa Valley Technical College) (CC BY 4.0)
  2. NCCPA PANCE Content Blueprint
  3. The Joint Commission, National Patient Safety Goals
  4. AAMC Core Entrustable Professional Activities (Core EPAs)

Facts and steps follow AAMC Core Entrustable Professional Activities (Core EPAs); NCCPA PANCE Content Blueprint. VMS is not affiliated with these organizations. Updated: 2026-10-11.