Test ID: LEU
Fecal Leukocytes
NY State Approved 
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Useful For Suggests clinical disorders or settings where the test may be helpful
Suggesting presence of pathogens such as Salmonella, Shigella, and amebiasis
Method Name A short description of the method used to perform the test
Microscopic
Includes trichrome stain.
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Aliases Lists additional common names for a test, as an aid in searching
Specimen Type Describes the specimen type needed for testing
Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
Container/Tube:
Preferred: ECOFIX preservative (Supply T219)
Acceptable: PVA preservative
Specimen Volume: Representative portion of collection
Collection Instructions:
1. Collect a random stool specimen.
2. Carefully follow instructions on container.
Forms: If not ordering electronically, submit a Microbiology Request Form (Supply T244) with the specimen.
Specimen Minimum Volume Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Reject Due To Identifies specimen types and conditions that may cause the specimen to be rejected
| Hemolysis | NA |
| Lipemia | NA |
| Icterus | NA |
| Other | NA |
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
| Specimen Type | Temperature | Time |
|---|---|---|
| Fecal | Ambient (preferred) | 21 days |
| Refrigerated | 21 days |
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Leukocytes are not normally seen in stools in the absence of infection or other inflammatory processes. Fecal leukocytosis is a response to infection with microorganisms that invade tissue or produce toxins, which causes tissue damage.
Fecal leukocytes are commonly found in patients with shigellosis and salmonellosis (erythrocytes) and sometimes in amebiasis. Mononuclear cells are found in typhoid fever.
Ulcerative colitis may also be associated with fecal leukocytosis.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Interpretive report
Interpretation Provides information to assist in interpretation of the test results
When fecal leukocytes are found they are reported in a semiquantitative manner: "few" indicates < or = 2/oil immersion microscopic field (OIF); "moderate" indicates 3/OIF to 9/OIF; "many" indicates > or = 10/OIF.
The greater the number of leukocytes, the greater the likelihood that an invasive pathogen is present. The finding of many fecal leukocytes is a good indicator of the presence of an invasive microbiological pathogen such as Salmonella or Shigella.
Few or no leukocytes and many erythrocytes suggests amebiasis.
Fecal leukocytes are rarely seen in diarrheas caused by other parasites or viruses.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Fecal leukocyte examinations cannot be performed on formalin-preserved specimens. Therefore, fresh, ECOFIX-preserved, or polyvinyl alcohol-preserved stool must be sent to the laboratory.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
Pickering LK, DuPont HL, Olarte J, et al: Fecal leukocytes in enteric infections. Am J Clin Pathol 1977;68:562-565
Method Description Describes how the test is performed and provides a method-specific reference
Feces preserved in ECOFIX preservative or polyvinyl alcohol are stained with trichrome. A differential count can be done if specifically requested, and many leukocytes have been seen. (Mayo Clinic Parasitology Laboratory Procedure Manual)
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 Saturday; Varies
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.
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location The location of the laboratory that performs the test
Test Classification Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
CPT Code Information Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
89055
LOINC® Code Information Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
| Result ID | Reporting Name | LOINC Code |
|---|---|---|
| LEU | Fecal Leukocytes | In Process |
External
link
PDF
document
Excel
document
Word
document