Test Details
Methodology
AST: kinetic; Platelet Count: automated cell counter
Result Turnaround Time
Within 1 day
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Use
AST to Platelet Ratio Index (APRI) is reported to be a simple, noninvasive and readily available laboratory test index that can stratify patients with HCV and nonalcoholic steatohepatitis (NASH), now known as metabolic dysfunction-associated steatohepatitis (MASH), who are at high or low risk for significant fibrosis and cirrhosis with high degree of accuracy.
Limitations
Clumping may cause false low platelet count. Platelet satellitism around neutrophils will cause a pseudothrombocytopenia. RBC or WBC fragments including fragmented fragile leukemic cells and neutrophil pseudoplatelets may cause falsely elevated counts.
References
Specimen Requirements
Specimen
Serum and whole blood
Volume
0.5 mL (serum); fill tube to capacity (whole blood)
Minimum Volume
0.5 mL (serum), 0.5 mL (whole blood)
Container
Gel-barrier tube or red-top tube and lavender-top (EDTA) tube
Collection Instructions
Separate serum from cells within 45 minutes of collection; invert EDTA tube immediately 8 to 10 times once tube is filled at the time of collection.
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 1 day |
Refrigerated | 3 days |
Frozen | Unstable |
Freeze/thaw cycles | Unstable |
Storage Instructions
Room temperature
Causes for Rejection
Serum: gross hemolysis; improper labeling
Whole blood: hemolysis; clotted specimen; tube not filled with minimum volume; improper labeling; transfer tubes with whole blood; specimen diluted or contaminated with IV fluid; specimen received with plasma removed; specimen collected in any anticoagulant other than EDTA
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 385375 | AST and Platelets with APRI | 001123 | AST (SGOT) | IU/L | 1920-8 | |
| 385375 | AST and Platelets with APRI | 015172 | Platelets | x10E3/uL | 777-3 | |
| 385375 | AST and Platelets with APRI | 011579 | APRI Index | 86465-2 | ||
| Order Code | 385375 | |||||
| Order Code Name | AST and Platelets with APRI | |||||
| Order Loinc | ||||||
| Result Code | 001123 | |||||
| Result Code Name | AST (SGOT) | |||||
| UofM | IU/L | |||||
| Result LOINC | 1920-8 | |||||
| Order Code | 385375 | |||||
| Order Code Name | AST and Platelets with APRI | |||||
| Order Loinc | ||||||
| Result Code | 015172 | |||||
| Result Code Name | Platelets | |||||
| UofM | x10E3/uL | |||||
| Result LOINC | 777-3 | |||||
| Order Code | 385375 | |||||
| Order Code Name | AST and Platelets with APRI | |||||
| Order Loinc | ||||||
| Result Code | 011579 | |||||
| Result Code Name | APRI Index | |||||
| UofM | ||||||
| Result LOINC | 86465-2 |