Fecal Leukocytes
Use
Fecal leukocytes are used as an indicator of infection or inflammatory processes within the gastrointestinal tract. The presence of fecal leukocytes suggests the possibility of pathogenic organisms such as Salmonella, Shigella, or amebiasis. Infections that cause tissue invasion or produce toxins that result in tissue damage lead to the presence of leukocytes in the stool. Clinically, these tests are relevant for identifying enteric infections that result in inflammatory diarrhea.
Special Instructions
Not provided.
Limitations
This test cannot be performed on specimens preserved in formalin. The test uses feces preserved in ECOFIX or Zinc Polyvinyl Alcohol (Zn-PVA) preservatives, as these do not interfere with the microscopic analysis. The presence of erythrocytes in a stool sample without leukocytes may still indicate the presence of an infection such as amebiasis. Moreover, the absence of fecal leukocytes does not rule out all infectious diarrhea, as not all pathogens cause leukocytosis.
FDA ApprovedNew York Approved
Methodology
Other
Biomarkers
Amebiasis
MicroorganismSalmonella
MicroorganismShigella
Microorganism
LOINC Codes
- 13655-6 - WBC Stl Ql Micro
- 13655-6 - WBC Stl Ql Micro
Result Turnaround Time
4-6 days
Related Documents
For more information, please review the documents below
Specimen
Stool
Volume
Not provided
Minimum Volume
5 mL
Container
ECOFIX preservative or Zinc Polyvinyl alcohol (Zn-PVA) vial
Collection Instructions
Collect a random fecal specimen. Place specimen into ECOFIX or Zinc-PVA preservative vial within 30 minutes of passage or collection. Follow the line on the preservative vial, and do not fill above it. Mix contents thoroughly by shaking.
Storage Instructions
Store and transport specimens at ambient temperature within 21 days using PVA or ECOFIX containers.
Causes for Rejection
Specimens preserved in formalin are rejected.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 21 days |
| Refrigerated | 21 days |