GRAM - Performance: Gram Stain

Test Catalog

Test Name

Test ID: GRAM    
Gram Stain

Method Description Describes how the test is performed and provides a method-specific reference

The specimen is applied directly to the slide or may be concentrated first by centrifugation or cytocentrifugation and then placed on the slide. The slide is stained with crystal violet, stained with Gram iodine solution, decolorized with acetone-alcohol, counterstained with safranin stain, and blotted dry. The slide is examined using the oil immersion objective on the microscope.(Chan WW: Gram Stain. In Clinical Microbiology Procedures Handbook. Vol 1. Fourth edition. Edited by AL Leber. Washington, DC, ASM Press, 2016. Section 3.2.1)

PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.

Monday through Sunday; Continuously

Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.

Same day/1 day

Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result

1 day

Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

Gram stained slides are retained for 7 days

Performing Laboratory Location The location of the laboratory that performs the test