Mayo Test ID LEU Fecal Leukocytes, Feces
Specimen Required
Supplies: ECOFIX Stool Transport Medium only (T790)
Container/Tube:
Preferred: ECOFIX preservative
Acceptable: Zinc Polyvinyl alcohol (Zn-PVA) preservative
Specimen Volume: Representative portion of collection
Collection Instructions:
1. Collect a random fecal specimen.
2. Carefully follow instructions on container.
a. Place specimen into ECOFIX preservative vial OR Zinc-PVA preservative vial within 30 minutes of passage or collection. Refer to the fill line on the preservative vial. Do not fill above the line indicated on the container.
b. Mix the contents of the tube with the spoon, twist the cap tightly closed, and shake vigorously until the contents are well mixed.
Useful For
Suggesting the presence of pathogens such as Salmonella, Shigella, and amebiasis
Method Name
Microscopic/Trichrome Stain
Reporting Name
Fecal LeukocytesSpecimen Type
FecalSpecimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Fecal | Ambient (preferred) | 21 days | PVA OR ECOFIX |
Refrigerated | 21 days | PVA OR ECOFIX |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Clinical Information
Leukocytes are not normally seen in feces 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 and sometimes in amebiasis. Mononuclear cells are found in typhoid fever.
Ulcerative colitis may also be associated with fecal leukocytosis.
Reference Values
An interpretive report will be provided.
Interpretation
When fecal leukocytes are found they are reported in a semi-quantitative manner: "few" indicates = 2/100x oil immersion microscopic field (OIF); "moderate" indicates 3-9/100x OIF; "many" indicates =10/100x OIF. Erythrocytes are reported in the same manner.
The greater the number of fecal leukocytes, the greater the likelihood that an invasive pathogen such as Salmonella or Shigella is present.
The presence of few or no leukocytes and many erythrocytes suggests possible amebiasis.
Fecal leukocytes are rarely seen in diarrhea caused by other parasites or viruses.
Cautions
Fecal leukocyte examinations cannot be performed on formalin-preserved specimens. Therefore, ECOFIX-preserved or zinc polyvinyl alcohol-preserved feces must be sent to the laboratory.
Clinical Reference
1. LaRocque RC and Harris JB: Syndromes of Enteric Infection. In: Bennett JE, Dolin R, and Blaser MJ, eds. Mandell, Douglas, and Bennett’s Principles and Practice of Infectious Diseases. 9th ed. Elsevier; 2020:chap 96
2. Harris JC, Dupont HL, Hornick RB. Fecal leukocytes in diarrheal illness. Ann Intern Med. 1972;76(5):697-703. doi:10.7326/0003-4819-76-5-697
3. Guerrant RL, Shields DS, Thorson SM, Schorling JB, Gröschel DH. Evaluation and diagnosis of acute infectious diarrhea. Am J Med. 1985;78(6B):91-98. doi:10.1016/0002-9343(85)90370-5
4. Pickering LK, DuPont HL, Olarte J, Conklin R, Ericsson C. Fecal leukocytes in enteric infections. Am J Clin Pathol. 1977;68(5):562-565. doi:10.1093/ajcp/68.5.562
Method Description
Feces preserved in ECOFIX preservative or polyvinyl alcohol are stained with trichrome.(Garcia LS: Diagnostic Medical Parasitology. 6th ed. ASM Press; 2016)
Day(s) Performed
Monday through Saturday
Report Available
4 to 6 daysSpecimen Retention Time
7 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
89055
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
LEU | Fecal Leukocytes | 13655-6 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
LEU | Fecal Leukocytes | 13655-6 |
Specimen Minimum Volume
5 mL