GUAIAC Diagnostic (Southeast Michigan, West ED and Rural Health Clinic Use Only)
Test Codes
EPIC: LAB2111554, Beaker: OCBFL
Department
Urinalysis
Specimen Collection Criteria
Collect: Gastric aspirate obtained by nasogastric intubation or vomitus in a sterile collection container.
- No special patient preparation is required.
- Send specimen to the Laboratory immediately after collection.
Physician Office/Draw Specimen Preparation
Maintain specimen at room temperature (20-26°C or 68-78.8°F) prior to transport.
Preparation for Courier Transport
Transport: Gastric specimen, at room temperature (20-26°C or 68-78.8°F).
Rejection Criteria
Specimens not collected and processed as indicated.
Storage
Specimen Stability for Testing:
Room Temperature (20-26°C or 68-78.8°F): 24 hours
Refrigerated (2-8°C or 36-46°F): 24 hours
Frozen (-20°C/-4°F or below): Unacceptable
Specimen Storage in Department Prior to Disposal:
Refrigerated (2-8°C or 36-46°F): 7 days
Laboratory
Grosse Pointe Microbiology Laboratory
Royal Oak Automated Chemistry Laboratory
Troy Chemistry Laboratory
Performed
Sunday – Saturday, 24 hours a day.
Routine results available within 24 hours of receipt in the Laboratory.
Reference Range
Negative.
Test Methodology
Colorimetric.
Interpretation
GastroccultTM is a screening test for presence of occult blood in a gastric aspirate. Many foods (e.g. incompletely cooked meat, raw fruits and vegetables) have peroxidase activity which may produce a false positive GastroccultTM test result. Thus, a positive result does not always indicate the presence of human blood.
Ascorbic Acid (Vitamin C) has been shown to cause false-negative test results for occult blood in feces. This can be expected to be true for the GastroccultTM test also.
As with any occult blood test, the results of the GastroccultTM test cannot be considered conclusive evidence of the presence or absence of upper gastrointestinal bleeding or pathology. Gastroccult tests are designed for preliminary screening as an aid to diagnosis. They are not intended to replace other diagnostic procedures such as gastroscopic examination or radiographic studies. Gastroccult test results should be used only in conjunction with other information relevant to the clinical status of the patient. A positive test result may suggest the need for more careful monitoring of the patient.
Clinical Utility
This assay provides a rapid screening method for detecting the presence of occult blood in gastric aspirates or vomitus. GastroccultTM slides are used to aid in the diagnosis and management of various gastric conditions. The identification of occult blood can be useful in the early detection of gastric trauma or deteriorating gastric conditions, and in evaluating antacid therapy.
Contacts
Chemistry Laboratory – GP
313-473-1807
Name: Chemistry Laboratory – GP
Location:
Phone: 313-473-1807
Automated Chemistry Laboratory – RO
248-551-8065
Name: Automated Chemistry Laboratory – RO
Location:
Phone: 248-551-8065
Microbiology Laboratory – TR
248-964-6127
Name: Microbiology Laboratory – TR
Location:
Phone: 248-964-6127
Last Updated
11/8/2024
Microtainer® and Vacutainer® are registered trademarks of Becton, Dickinson and Company.
UroVysion® is a registered trademark of Abbott Laboratories. ThinPrep® is a registered trademark of Hologic, Incorporated.