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HelpTest ID GRAM Gram Stain
Useful For
Identifying microorganisms in normally sterile body fluids
Screening sputum specimens for acceptability for bacterial culture
Guiding initial antimicrobial therapy
Method Name
Conventional Gram Stain Procedure
Reporting Name
Gram StainSpecimen Type
VariesPreferred:
Specimen Type: Original specimen
Sources: Closed/open abscess, lower respiratory, fluid, tissue, or swab
Container/Tube: Sterile container or culture transport swab
Specimen Volume: Entire collection
Acceptable:
Specimen Type: Prepared microscope slide
Sources: Closed/open abscess, lower respiratory, fluid, tissue, or swab
Collection Container/Tube: Sterile container or culture transport swab
Submission Container/Tube: Slide container
Specimen Volume: Slide
Collection Instructions: Apply original sample to surface of standard microscope slide using appropriate application method (determined by consistency of specimen type) to assure adequate transfer of specimen onto slide. Allow specimen to dry and then heat-fix the slide. Place in slide container for transport.
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Varies | Refrigerated (preferred) | 24 hours |
| Ambient | 24 hours |
Clinical Information
The Gram stain is a general stain used extensively in microbiology for the preliminary differentiation of microbiological organisms. The Gram stain is one of the simplest, least expensive, and most useful of the rapid methods used to identify and classify bacteria.
The Gram stain is used to provide preliminary information concerning the type of organisms present directly from clinical specimens or from growth on culture plates. This stain is used to identify the presence of microorganisms in normally sterile body fluids (cerebrospinal fluid, synovial fluid, pleural fluid, peritoneal fluid). It is also used to screen sputum specimens to establish acceptability for bacterial culture (<25 squamous epithelial cells per field is considered an acceptable specimen for culture) and may reveal the causative organism in bacterial pneumonia.
Reference Values
No organisms seen or descriptive report of observations.
Cautions
Overdecolorization may result in the loss of the crystal violet iodine complex from gram-positive organisms and result in a misinterpretation.
Day(s) Performed
Monday through Sunday; Continuously
Report Available
1 hourPerforming Laboratory
Mayo Medical Laboratories in Rochester
Test Classification
This test uses a standard method. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
87205