Test Code ASFT Acid Fast Stain, Fecal
Clinical Indications
Modified Acid Fast Staining for the identification of intestinal protozoa (Cyclospora cayetanensis, Cryptosporidium species, and Cystoiospora belli)
Additional Test Codes
Epic Order Code: Acid Fast Stain, Fecal
Sunquest Order Code: ASFT
Px Order Code: LAB4000
Specimen Collection Type
Raw stool in a sterile container or EcoFix preservative (do not
fill past the line on the vial)
Bristol stool types 1-7
Raw stool should be submitted to the lab within 30 minutes of
collection.
Minimum Collection Volume
5 g or 0.5 mL
Reference Range
Negative
Critical Value
N/A
Interpretation
A positive result indicates the presence of intestinal
protozoa.
For the detection of Giardia and Cryptosporidium,
fecal antigen testing is recommended.
A single negative result cannot exclude the possibility of
infection with intestinal protozoa; a minimum of 3 stool specimens
are recommended for optimal sensitivity (1 each day or on alternate
days).
This test is not useful for the detection of helminth infections,
microsporidia, or free-living amoeba.
Rejection Criteria
Parasite testing is not performed on patients hospitalized >3
days.
Stool in Para-Pak (C&S) vial
Stool contaminated with urine
Specimen Availability for Add-on Testing
7 days
Specimen Stability
In preservative, 7 days at room temperature
Day(s) Performed
Monday through Friday
Performing Lab- Department
TUKHS-BH-Microbiology
CPT Code
87206
LOINC Code
655-1
Test Alias
N/A
Additional Information / Notes
Specimen collection should be delayed 7-10 days after administration of barium, castor oil, mineral oil and antidiarrheal medications. Antibiotics may interfere with identification of protozoa.