Gram Stain

Sunquest Code:GRAM  
Epic Code:LAB250Epic Name:Gram Stain
Synonyms:Bacterial Smear
Methodology:Gram stain
Test Includes:Microscopic exam of Gram stained specimen. Preliminary review performed on all STAT requests and all CSF, subdural fluid, and subarachnoid fluid at UMMC/UMMCH West Bank, FSH, Fairview Range and FRMC prior to sending to the Infectious Diseases Diagnostic Laboratory (IDDL).
Turnaround Time:Performed 24 hours/day; results are reported in approximately 4 hours for routine testing, and 30-60 minutes for STAT testing.
Special Instructions:Indicate specimen site on request form.

Collection Instructions

Specimen:Fluid, tissue, aspirate, respiratory (sputum and bronchial) and swabbed anatomical sites.
Fluid, tissue and aspirate is always preferred over swab, when possible.
Automatically performed on: CSF, subdural fluid, subarachnoid fluid, sputum (expectorated), and vaginal. Other specimen types require a specific request.
Optimal Volume:3 mL fluid or aspirate
Minimum\Peds Volume:0.5 mL fluid or aspirate. Tissue must be visible.
Container:Plastic leakproof container, sterile, See Collection Instructions (CoPan ESwab with larger swab)
Collection Instructions:
Sterile Container:
  • Optimal volume: 3 mL
  • Minimum volume: 0.5 mL
  • Optimal: visible tissue
  • Minimum volume: 0.5 mL
  • Optimal volume: 2 mL
  • Minimum volume: 0.5 mL
CoPan ESwab (for swabbed anatomical sites only):
Any swabbed anatomical stie (i.e. superficial wound, vagina for Bacterial Vaginosis, etc.)
Never use for fluid tissue, aspirate or lower respiratory collections.
Causes for Rejection:Not an adequately sensitive test on direct blood films; not useful on throat or fecal specimens except to screen for overgrowth of yeast. Gram stain may not be possible on hard bone specimens or foreign bodies (i.e., catheter tips) without the presence of soft tissue or purulent material. Testing on these specimens may be canceled at laboratory's discretion.

Processing and Shipping

Specimen Processing:Store at room temperature.
Shipping Instructions:Ship slides at room temperature in protective slide holder. If a culture is also requested, laboratory will use the original specimen to prepare a smear and a separate slide is not required.
Test Performed at or Referral Lab Infectious Diseases Diagnostic Laboratory  (UMMC-East Bank, Microbiology (GICH))


Reference Range:No organisms seen.
Use:Provides preliminary information regarding presence or absence of bacteria, yeast, neutrophils, epithelial cells, pathogenic organisms, anaerobic organisms, Sensitivity of culture is significantly higher as compared to gram stain alone. Culture also allows antibacterial susceptibility testing of pathogenic organisms. It is recommended to order appropriate culture in conjunction with gram stain. Diagnosis of bacterial vaginosis does not required a culture. May be helpful for diagnosis of moniliasis (thrush).

Click HERE to Report test errors or omissions.
*If no email program is associated with this computer, please contact: for TestID: 729"