Laboratory Services

Gram Stain

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Updated Test Information:

Test Description
Gram Stain

Gram Stain, Bacterial Smear, Gram Slide, Bacterial Stain

Test ID
General Information

Determine the presence or absence of microorganisms and white blood cells from clinical specimens, can also be used to evaluate the quality of the specimen.

Specimen Type

Clinical Material

Specimen Requirements

Bacterial Culture Transport Swab w/gel, Amies Transport swab, Eswab, Clinical material in a sterile container. Other transport systems also accepted.

Minimum Sample Volume

Inoculated swab or visible material in sterile container

Additional Processing Details

Gram stain is included with Wound, Ear, Eye, Sinus, Sputum, Genital, and Sterile Body fluid cultures


Ambient: 48 hours
Refrigerated: 48 hours

Unacceptable Specimen Conditions

Unacceptable specimen transport device (including Incyte Swab, specimen in formalin, expired), improper labeling, prolonged delay in transport (greater than 48 hours)


Organism identification and susceptibility testing will only be performed if a culture is requested. Request for Gram stain will not reflex to a culture. Gram stain alone is not reliable for diagnosis of infection.


Manual stain

Estimated TAT

1-2 days

Testing Schedule

Monday-Saturday, & STAT

CPT Code(s)


Reference Range

Depends on specimen source.

Reflex Conditions

None. Gram stain does NOT reflex to culture.

Performing Lab

Incyte Diagnostics

LOINC Code(s)


Additional Information

Gram stain is a general stain used extensively in microbiology for the preliminary differentiation of microbiological organisms.